151
|
Cunha PVP, Herdeiro C, Radu E, Sanchis-Gual N. Exotic Compact Objects and the Fate of the Light-Ring Instability. PHYSICAL REVIEW LETTERS 2023; 130:061401. [PMID: 36827558 DOI: 10.1103/physrevlett.130.061401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 12/06/2022] [Indexed: 06/18/2023]
Abstract
Ultracompact objects with light rings (LRs) but without an event horizon could mimic black holes (BHs) in their strong gravity phenomenology. But are such objects dynamically viable? Stationary and axisymmetric ultracompact objects that can form from smooth, quasi-Minkowski initial data must have at least one stable LR, which has been argued to trigger a spacetime instability; but its development and fate have been unknown. Using fully nonlinear numerical evolutions of ultracompact bosonic stars free of any other known instabilities and introducing a novel adiabatic effective potential technique, we confirm the LRs triggered instability, identifying two possible fates: migration to nonultracompact configurations or collapse to BHs. In concrete examples we show that typical migration (collapse) timescales are not larger than ∼10^{3} light-crossing times, unless the stable LR potential well is very shallow. Our results show that the LR instability is effective in destroying horizonless ultracompact objects that could be plausible BH imitators.
Collapse
Affiliation(s)
- Pedro V P Cunha
- Departamento de Matemática da Universidade de Aveiro and Centre for Research and Development in Mathematics and Applications (CIDMA), Campus de Santiago, 3810-183 Aveiro, Portugal
| | - Carlos Herdeiro
- Departamento de Matemática da Universidade de Aveiro and Centre for Research and Development in Mathematics and Applications (CIDMA), Campus de Santiago, 3810-183 Aveiro, Portugal
| | - Eugen Radu
- Departamento de Matemática da Universidade de Aveiro and Centre for Research and Development in Mathematics and Applications (CIDMA), Campus de Santiago, 3810-183 Aveiro, Portugal
| | - Nicolas Sanchis-Gual
- Departamento de Matemática da Universidade de Aveiro and Centre for Research and Development in Mathematics and Applications (CIDMA), Campus de Santiago, 3810-183 Aveiro, Portugal
- Departamento de Astronomía y Astrofísica, Universitat de València, Dr. Moliner 50, 46100 Burjassot (València), Spain
| |
Collapse
|
152
|
Koehlenbeck SM, Mow-Lowry CM, Bergmann G, Kirchoff R, Koch P, Kühn G, Lehmann J, Oppermann P, Wöhler J, Wu DS. A study on motion reduction for suspended platforms used in gravitational wave detectors. Sci Rep 2023; 13:2388. [PMID: 36765077 PMCID: PMC9918497 DOI: 10.1038/s41598-023-29418-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Accepted: 02/03/2023] [Indexed: 02/12/2023] Open
Abstract
We report a reduction in motion for suspended seismic-isolation platforms in a gravitational wave detector prototype facility. We sense the distance between two seismic-isolation platforms with a suspension platform interferometer and the angular motion with two optical levers. Feedback control loops reduce the length changes between two platforms separated by [Formula: see text] to [Formula: see text] at [Formula: see text], and the angular motion of each platform is reduced to [Formula: see text] at [Formula: see text]. As a result, the length fluctuations in a suspended optical resonator on top of the platforms is reduced by three orders of magnitude. This result is of direct relevance to gravitational wave detectors that use similar suspended optics and seismic isolation platforms.
Collapse
Affiliation(s)
- Sina M. Koehlenbeck
- grid.450243.40000 0001 0790 4262Max Planck Institute for Gravitational Physics (Albert Einstein Institute), 30167 Hanover, Germany ,grid.9122.80000 0001 2163 2777Institut für Gravitationsphysik, Leibniz Universität Hannover, 30167 Hanover, Germany
| | - Conor M. Mow-Lowry
- grid.12380.380000 0004 1754 9227Faculty of Science, (Astro)-Particles Physics, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands
| | - Gerald Bergmann
- grid.450243.40000 0001 0790 4262Max Planck Institute for Gravitational Physics (Albert Einstein Institute), 30167 Hanover, Germany ,grid.9122.80000 0001 2163 2777Institut für Gravitationsphysik, Leibniz Universität Hannover, 30167 Hanover, Germany
| | - Robin Kirchoff
- grid.450243.40000 0001 0790 4262Max Planck Institute for Gravitational Physics (Albert Einstein Institute), 30167 Hanover, Germany ,grid.9122.80000 0001 2163 2777Institut für Gravitationsphysik, Leibniz Universität Hannover, 30167 Hanover, Germany
| | - Philip Koch
- grid.450243.40000 0001 0790 4262Max Planck Institute for Gravitational Physics (Albert Einstein Institute), 30167 Hanover, Germany ,grid.9122.80000 0001 2163 2777Institut für Gravitationsphysik, Leibniz Universität Hannover, 30167 Hanover, Germany
| | - Gerrit Kühn
- grid.450243.40000 0001 0790 4262Max Planck Institute for Gravitational Physics (Albert Einstein Institute), 30167 Hanover, Germany ,grid.9122.80000 0001 2163 2777Institut für Gravitationsphysik, Leibniz Universität Hannover, 30167 Hanover, Germany
| | - Johannes Lehmann
- grid.450243.40000 0001 0790 4262Max Planck Institute for Gravitational Physics (Albert Einstein Institute), 30167 Hanover, Germany ,grid.9122.80000 0001 2163 2777Institut für Gravitationsphysik, Leibniz Universität Hannover, 30167 Hanover, Germany
| | - Patrick Oppermann
- grid.418028.70000 0001 0565 1775Fritz Haber Institute of the Max Planck Society, 14195 Berlin, Germany
| | - Janis Wöhler
- grid.450243.40000 0001 0790 4262Max Planck Institute for Gravitational Physics (Albert Einstein Institute), 30167 Hanover, Germany ,grid.9122.80000 0001 2163 2777Institut für Gravitationsphysik, Leibniz Universität Hannover, 30167 Hanover, Germany
| | - David S. Wu
- grid.450243.40000 0001 0790 4262Max Planck Institute for Gravitational Physics (Albert Einstein Institute), 30167 Hanover, Germany ,grid.9122.80000 0001 2163 2777Institut für Gravitationsphysik, Leibniz Universität Hannover, 30167 Hanover, Germany
| |
Collapse
|
153
|
Faraoni V, Jose S. Cosmological analogies for geophysical flows, Lagrangians, and new analogue gravity systems. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2023; 83:130. [PMID: 36785556 PMCID: PMC9911491 DOI: 10.1140/epjc/s10052-023-11292-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Accepted: 02/02/2023] [Indexed: 06/18/2023]
Abstract
Formal analogies between the ordinary differential equations describing geophysical flows and Friedmann cosmology are developed. As a result, one obtains Lagrangian and Hamiltonian formulations of these equations, while laboratory experiments aimed at testing geophysical flows are shown to constitute analogue gravity systems for cosmology.
Collapse
Affiliation(s)
- Valerio Faraoni
- Department of Physics and Astronomy, Bishop’s University, 2600 College Street, Sherbrooke, QC J1M 1Z7 Canada
| | - Sonia Jose
- Department of Physics and Astronomy, Bishop’s University, 2600 College Street, Sherbrooke, QC J1M 1Z7 Canada
| |
Collapse
|
154
|
Multiverse as an Ensemble of Stable and Unstable Universes. Symmetry (Basel) 2023. [DOI: 10.3390/sym15020473] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023] Open
Abstract
Estimates of the Higgs and top quark masses, mH≃125.10±0.14 [GeV] and mt≃172.76±0.30 [GeV], based on the experimental result place the Standard Model in the region of the metastable vacuum. A consequence of the metastability of the Higgs vacuum is that it should induce the decay of the electroweak vacuum in the early Universe with catastrophic consequences. It may happen that certain universes were lucky enough to survive the time of canonical decay, that is the exponential decay, and live longer. This means that it is reasonable to analyze conditions allowing for that. We analyze the properties of an ensemble of universes with unstable vacua considered as an ensemble of unstable systems from the point of view of the quantum theory of unstable states. We found some symmetry relations for quantities characterizing the metastable state. We also found a relation linking the decay rate Γ of the metastable vacuum state with the Hubble parameter H(t), which may help to explain why a universe with an unstable vacuum that lives longer then the canonical decay times does not necessarily decay.
Collapse
|
155
|
Schmitz GJ, te Vrugt M, Haug-Warberg T, Ellingsen L, Needham P, Wittkowski R. Thermodynamics of an Empty Box. ENTROPY (BASEL, SWITZERLAND) 2023; 25:315. [PMID: 36832681 PMCID: PMC9955345 DOI: 10.3390/e25020315] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 01/15/2023] [Accepted: 02/03/2023] [Indexed: 06/18/2023]
Abstract
A gas in a box is perhaps the most important model system studied in thermodynamics and statistical mechanics. Usually, studies focus on the gas, whereas the box merely serves as an idealized confinement. The present article focuses on the box as the central object and develops a thermodynamic theory by treating the geometric degrees of freedom of the box as the degrees of freedom of a thermodynamic system. Applying standard mathematical methods to the thermodynamics of an empty box allows equations with the same structure as those of cosmology and classical and quantum mechanics to be derived. The simple model system of an empty box is shown to have interesting connections to classical mechanics, special relativity, and quantum field theory.
Collapse
Affiliation(s)
- Georg J. Schmitz
- MICRESS Group, ACCESS e.V., Intzestr. 5, D-52072 Aachen, Germany
| | - Michael te Vrugt
- Institut für Theoretische Physik, Center for Soft Nanoscience, Westfälische Wilhelms-Universität Münster, D-48149 Münster, Germany
| | - Tore Haug-Warberg
- Department of Chemical Engineering, Norwegian University of Science and Technology (NTNU), N-7491 Trondheim, Norway
| | - Lodin Ellingsen
- Department of Chemical Engineering, Norwegian University of Science and Technology (NTNU), N-7491 Trondheim, Norway
| | - Paul Needham
- Department of Philosophy, University of Stockholm, SE-106 91 Stockholm, Sweden
| | - Raphael Wittkowski
- Institut für Theoretische Physik, Center for Soft Nanoscience, Westfälische Wilhelms-Universität Münster, D-48149 Münster, Germany
| |
Collapse
|
156
|
Gravity as a Quantum Field Theory. Symmetry (Basel) 2023. [DOI: 10.3390/sym15020449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023] Open
Abstract
Classical gravity is understood as the geometry of spacetime, and it seems very different from the other known interactions. In this review, I will instead stress the analogies: Like strong interactions, the low energy effective field theory of gravity is related to a nonlinearly realized symmetry, and like electroweak interactions, it is a gauge theory in Higgs phase, with a massive connection. I will also discuss the possibility of finding a UV complete quantum field theoretic description of all interactions.
Collapse
|
157
|
Guo Y, Hadzic M, Jang J. Naked Singularities in the Einstein-Euler System. ANNALS OF PDE 2023; 9:4. [PMID: 36778526 PMCID: PMC9905257 DOI: 10.1007/s40818-022-00144-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 12/15/2022] [Indexed: 06/18/2023]
Abstract
In 1990, based on numerical and formal asymptotic analysis, Ori and Piran predicted the existence of selfsimilar spacetimes, called relativistic Larson-Penston solutions, that can be suitably flattened to obtain examples of spacetimes that dynamically form naked singularities from smooth initial data, and solve the radially symmetric Einstein-Euler system. Despite its importance, a rigorous proof of the existence of such spacetimes has remained elusive, in part due to the complications associated with the analysis across the so-called sonic hypersurface. We provide a rigorous mathematical proof. Our strategy is based on a delicate study of nonlinear invariances associated with the underlying non-autonomous dynamical system to which the problem reduces after a selfsimilar reduction. Key technical ingredients are a monotonicity lemma tailored to the problem, an ad hoc shooting method developed to construct a solution connecting the sonic hypersurface to the so-called Friedmann solution, and a nonlinear argument to construct the maximal analytic extension of the solution. Finally, we reformulate the problem in double-null gauge to flatten the selfsimilar profile and thus obtain an asymptotically flat spacetime with an isolated naked singularity.
Collapse
Affiliation(s)
- Yan Guo
- Division of Applied Mathematics, Brown University, Providence, RI 02912 USA
| | - Mahir Hadzic
- Department of Mathematics, University College London, London, UK
| | - Juhi Jang
- Department of Mathematics, University of Southern California, Los Angeles, CA 90089 USA
- Korea Institute for Advanced Study, Seoul, Korea
| |
Collapse
|
158
|
Li Z. Scalar perturbation around rotating regular black hole: Superradiance instability and quasinormal modes. Int J Clin Exp Med 2023. [DOI: 10.1103/physrevd.107.044013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
|
159
|
Blanco FM, Flanagan ÉÉ. Particle Motion under the Conservative Piece of the Self-Force is Hamiltonian. PHYSICAL REVIEW LETTERS 2023; 130:051201. [PMID: 36800446 DOI: 10.1103/physrevlett.130.051201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Accepted: 12/06/2022] [Indexed: 06/18/2023]
Abstract
We consider the motion of a point particle in a stationary spacetime under the influence of a scalar, electromagnetic, or gravitational self-force. We show that the conservative piece of the first-order self-force gives rise to Hamiltonian dynamics, and we derive an explicit expression for the Hamiltonian on phase space. Specialized to the Kerr spacetime, our result generalizes the Hamiltonian function previously obtained by Fujita et al. [Classical Quantum Gravity 34, 134001 (2017).CQGRDG0264-938110.1088/1361-6382/aa7342], which is valid only for nonresonant orbits.
Collapse
Affiliation(s)
| | - Éanna É Flanagan
- Department of Physics, Cornell University, Ithaca, New York 14853, USA
| |
Collapse
|
160
|
Battista E, De Falco V, Usseglio D. First post-Newtonian N-body problem in Einstein-Cartan theory with the Weyssenhoff fluid: Lagrangian and first integrals. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2023; 83:112. [PMID: 36776578 PMCID: PMC9910320 DOI: 10.1140/epjc/s10052-023-11249-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 01/21/2023] [Indexed: 06/18/2023]
Abstract
The rotational dynamics of an N-body system at the first post-Newtonian order in Einstein-Cartan theory is derived. This result is achieved by performing the point-particle limit of the equations of motion of the Weyssenhoff fluid, which models the quantum spin effects residing inside the bodies. For the special case of binary systems, we determine the Lagrangian function and the resulting first integrals underlying the translational dynamics and the spin precession.
Collapse
Affiliation(s)
- Emmanuele Battista
- Department of Physics, University of Vienna, Boltzmanngasse 5, 1090 Vienna, Austria
| | - Vittorio De Falco
- Scuola Superiore Meridionale, Largo San Marcellino 10, 80138 Naples, Italy
- Istituto Nazionale di Fisica Nucleare, Sezione di Napoli, Complesso Universitario di Monte S. Angelo, Via Cintia Edificio 6, 80126 Naples, Italy
| | - Davide Usseglio
- Scuola Superiore Meridionale, Largo San Marcellino 10, 80138 Naples, Italy
- Istituto Nazionale di Fisica Nucleare, Sezione di Napoli, Complesso Universitario di Monte S. Angelo, Via Cintia Edificio 6, 80126 Naples, Italy
| |
Collapse
|
161
|
Bahamonde S, Dialektopoulos KF, Escamilla-Rivera C, Farrugia G, Gakis V, Hendry M, Hohmann M, Levi Said J, Mifsud J, Di Valentino E. Teleparallel gravity: from theory to cosmology. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2023; 86:026901. [PMID: 36279849 DOI: 10.1088/1361-6633/ac9cef] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 10/24/2022] [Indexed: 06/16/2023]
Abstract
Teleparallel gravity (TG) has significantly increased in popularity in recent decades, bringing attention to Einstein's other theory of gravity. In this Review, we give a comprehensive introduction to how teleparallel geometry is developed as a gauge theory of translations together with all the other properties of gauge field theory. This relates the geometry to the broader metric-affine approach to forming gravitational theories where we describe a systematic way of constructing consistent teleparallel theories that respect certain physical conditions such as local Lorentz invariance. We first use TG to formulate a teleparallel equivalent of general relativity (GR) which is dynamically equivalent to GR but which may have different behaviors for other scenarios, such as quantum gravity. After setting this foundation, we describe the plethora of modified teleparallel theories of gravity that have been proposed in the literature. We attempt to connect them together into general classes of covariant gravitational theories. Of particular interest, we highlight the recent proposal of a teleparallel analogue of Horndeski gravity which offers the possibility of reviving all of the regular Horndeski contributions. In the second part of the Review, we first survey works in teleparallel astrophysics literature where we focus on the open questions in this regime of physics. We then discuss the cosmological consequences for the various formulations of TG. We do this at background level by exploring works using various approaches ranging from dynamical systems to Noether symmetries, and more. Naturally, we then discuss perturbation theory, firstly by giving a concise approach in which this can be applied in TG theories and then apply it to a number of important theories in the literature. Finally, we examine works in observational and precision cosmology across the plethora of proposal theories. This is done using some of the latest observations and is used to tackle cosmological tensions which may be alleviated in teleparallel cosmology. We also introduce a number of recent works in the application of machine learning to gravity, we do this through deep learning and Gaussian processes, together with discussions about other approaches in the literature.
Collapse
Affiliation(s)
- Sebastian Bahamonde
- Laboratory of Theoretical Physics, Institute of Physics, University of Tartu, W. Ostwaldi 1, 50411 Tartu, Estonia
- Department of Physics, Tokyo Institute of Technology, 1-12-1 Ookayama, Meguro-ku, Tokyo 152-8551, Japan
| | - Konstantinos F Dialektopoulos
- Center for Gravitation and Cosmology, College of Physical Science and Technology, Yangzhou University, Yangzhou 225009, People's Republic of China
- Laboratory of Physics, Faculty of Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece
- Department of Physics, Nazarbayev University, 53 Kabanbay Batyr Avenue, 010000 Astana, Kazakhstan
| | - Celia Escamilla-Rivera
- Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, Circuito Exterior C.U., A.P. 70-543, México D.F. 04510, Mexico
| | - Gabriel Farrugia
- Institute of Space Sciences and Astronomy, University of Malta, Msida, Malta
- Department of Physics, University of Malta, Msida, Malta
| | - Viktor Gakis
- Institute of Space Sciences and Astronomy, University of Malta, Msida, Malta
- Department of Physics, University of Malta, Msida, Malta
- Department of Physics, National Technical University of Athens, Zografou Campus GR 157 73, Athens, Greece
| | - Martin Hendry
- SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - Manuel Hohmann
- Laboratory of Theoretical Physics, Institute of Physics, University of Tartu, W. Ostwaldi 1, 50411 Tartu, Estonia
| | - Jackson Levi Said
- Institute of Space Sciences and Astronomy, University of Malta, Msida, Malta
- Department of Physics, University of Malta, Msida, Malta
| | - Jurgen Mifsud
- Institute of Space Sciences and Astronomy, University of Malta, Msida, Malta
- Department of Physics, University of Malta, Msida, Malta
| | - Eleonora Di Valentino
- Institute for Particle Physics Phenomenology, Department of Physics, Durham University, Durham DH1 3LE, United Kingdom
| |
Collapse
|
162
|
McDermott R. On the scientific study of small samples: Challenges confronting quantitative and qualitative methodologies. THE LEADERSHIP QUARTERLY 2023. [DOI: 10.1016/j.leaqua.2023.101675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
|
163
|
Series Solution of the Time-Dependent Schrödinger–Newton Equations in the Presence of Dark Energy via the Adomian Decomposition Method. Symmetry (Basel) 2023. [DOI: 10.3390/sym15020372] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The Schrödinger–Newton model is a nonlinear system obtained by coupling the linear Schrödinger equation of canonical quantum mechanics with the Poisson equation of Newtonian mechanics. In this paper, we investigate the effects of dark energy on the time-dependent Schrödinger–Newton equations by including a new source term with energy density proportional to the cosmological constant Λ, in addition to the particle-mass source term. The resulting Schrödinger–Newton–Λ (S-N-Λ) system cannot be solved exactly, in closed form, and one must resort to either numerical or semianalytical (i.e., series) solution methods. We apply the Adomian Decomposition Method, a very powerful method for solving a large class of nonlinear ordinary and partial differential equations, to obtain accurate series solutions of the S-N-Λ system, for the first time. The dark energy dominated regime is also investigated in detail. We then compare our results to existing numerical solutions and analytical estimates and show that they are consistent with previous findings. Finally, we outline the advantages of using the Adomian Decomposition Method, which allows accurate solutions of the S-N-Λ system to be obtained quickly, even with minimal computational resources. The extensive use of the Adomian Decomposition Method in the field of quantum mechanics and quantum field theory may open new mathematical, and physical, perspectives on obtaining semi-analytical solutions for some complex problems of quantum theory.
Collapse
|
164
|
Arregui G, Ng RC, Albrechtsen M, Stobbe S, Sotomayor-Torres CM, García PD. Cavity Optomechanics with Anderson-Localized Optical Modes. PHYSICAL REVIEW LETTERS 2023; 130:043802. [PMID: 36763436 DOI: 10.1103/physrevlett.130.043802] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 12/16/2022] [Indexed: 06/18/2023]
Abstract
Confining photons in cavities enhances the interaction between light and matter. In cavity optomechanics, this enables a wealth of phenomena ranging from optomechanically induced transparency to macroscopic objects cooled to their motional ground state. Previous work in cavity optomechanics employed devices where ubiquitous structural disorder played no role beyond perturbing resonance frequencies and quality factors. More generally, the interplay between disorder, which must be described by statistical physics, and optomechanical effects has thus far been unexplored. Here, we demonstrate how sidewall roughness in air-slot photonic-crystal waveguides can induce sufficiently strong backscattering of slot-guided light to create Anderson-localized modes with quality factors as high as half a million and mode volumes estimated to be below the diffraction limit. We observe how the interaction between these disorder-induced optical modes and in-plane mechanical modes of the slotted membrane is governed by a distribution of coupling rates, which can exceed g_{o}/2π∼200 kHz, leading to mechanical amplification up to self sustained oscillations via optomechanical backaction. Our Letter constitutes the first steps towards understanding optomechanics in the multiple-scattering regime and opens new perspectives for exploring complex systems with a multitude of mutually coupled degrees of freedom.
Collapse
Affiliation(s)
- G Arregui
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology, Campus UAB, Bellaterra, 08193 Barcelona, Spain
- DTU Electro, Department of Electrical and Photonics Engineering, Technical University of Denmark, Ørsteds Plads 343, Kgs. Lyngby, DK-2800, Denmark
| | - R C Ng
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology, Campus UAB, Bellaterra, 08193 Barcelona, Spain
| | - M Albrechtsen
- DTU Electro, Department of Electrical and Photonics Engineering, Technical University of Denmark, Ørsteds Plads 343, Kgs. Lyngby, DK-2800, Denmark
| | - S Stobbe
- DTU Electro, Department of Electrical and Photonics Engineering, Technical University of Denmark, Ørsteds Plads 343, Kgs. Lyngby, DK-2800, Denmark
| | - C M Sotomayor-Torres
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology, Campus UAB, Bellaterra, 08193 Barcelona, Spain
- ICREA-Institució Catalana de Recerca i Estudis Avançats, 08010 Barcelona, Spain
| | - P D García
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology, Campus UAB, Bellaterra, 08193 Barcelona, Spain
| |
Collapse
|
165
|
Fathollahi L, Wu F, Pongracic B. Gravitational redshift test using Rb clocks of eccentric GPS satellites. Heliyon 2023; 9:e13178. [PMID: 36747516 PMCID: PMC9898677 DOI: 10.1016/j.heliyon.2023.e13178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Revised: 11/27/2022] [Accepted: 01/19/2023] [Indexed: 01/26/2023] Open
Abstract
This paper reports a test of gravitational redshift, which is a consequence of the Einstein equivalence principle, using the Rb clocks of GPS Block IIF satellites. The fractional deviation in the gravitational redshift was measured using 6,640 days of data from three Rb clocks onboard GPS Block IIF satellites. The systematic effects related to orbital uncertainty, temperature, and magnetic field were modeled conservatively. The fractional deviation in the gravitational redshift from the general relativity prediction was measured with ( 0.23 ± 1.34 ) × 10 - 3 at one sigma.
Collapse
Affiliation(s)
- Loghman Fathollahi
- SNARS Laboratory, School of Instrumentation and Optoelectronic Engineering, Beihang University, Beijing, China
| | - Falin Wu
- SNARS Laboratory, School of Instrumentation and Optoelectronic Engineering, Beihang University, Beijing, China
- Corresponding author.
| | | |
Collapse
|
166
|
Reconstruction of Scalar-Torsion Gravity Theories from the Physical Potential of a Scalar Field. Symmetry (Basel) 2023. [DOI: 10.3390/sym15020291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
We consider scalar-torsion gravity theories based on the exact solutions of a physical type of potential for cosmological inflationary models based on the non-minimal coupling of a scalar field and torsion. We analyzed the inflationary models with different types of inflationary dynamics and corresponding scalar field parameters. Such an approach allows us to consider different physical potentials and types of scalar-torsion gravity theories in the context of the realization of both stages of accelerated expansion of the universe. We also considered the correspondence surrounding the proposed inflationary models and the observational constraints on the parameters of cosmological perturbations.
Collapse
|
167
|
Orbits of Particles and Photons around Regular Rotating Black Holes and Solitons. Symmetry (Basel) 2023. [DOI: 10.3390/sym15020273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
We briefly overview the basic properties and generic behavior of circular equatorial particle orbits and light rings around regular rotating compact objects with dark energy interiors, which are described by regular metrics of the Kerr–Schild class and include rotating black holes and self-gravitating spinning solitons replacing naked singularities. These objects have an internal de Sitter vacuum disk and can have two types of dark interiors, depending on the energy conditions. The first type reduces to the de Sitter disk, the second contains a closed de Sitter surface and an S surface with the de Sitter disk as the bridge and an anisotropic phantom fluid in the regions between the S surface and the disk. In regular geometry, the potentials decrease from V(r)→∞ to their minima, which ensures the existence of the innermost stable photon and particle orbits that are essential for processes of energy extraction occurring within the ergoregions, which for the second type of interiors contain the phantom energy. The innermost orbits provide a diagnostic tool for investigation of dark interiors of de Sitter–Kerr objects. They include light rings which confine these objects and ensure the most informative observational signature for rotating black holes presented by their shadows.
Collapse
|
168
|
Forteza XJ, Bhagwat S, Kumar S, Pani P. Novel Ringdown Amplitude-Phase Consistency Test. PHYSICAL REVIEW LETTERS 2023; 130:021001. [PMID: 36706405 DOI: 10.1103/physrevlett.130.021001] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 10/13/2022] [Accepted: 11/15/2022] [Indexed: 06/18/2023]
Abstract
The ringdown signal emitted during a binary black hole coalescence can be modeled as a linear superposition of the characteristic damped modes of the remnant black hole that get excited during the merger phase. While checking the consistency of the measured frequencies and damping times against the Kerr BH spectrum predicted by general relativity (GR) is a cornerstone of strong-field tests of gravity, the consistency of measured excitation amplitudes and phases have been largely left unexplored. For a nonprecessing, quasicircular binary black hole merger, we find that GR predicts a narrow region in the space of mode amplitude ratio and phase difference, independently of the spin of the binary components. Using this unexpected result, we develop a new null test of strong-field gravity which demands that the measured amplitudes and phases of different ringdown modes should lie within this narrow region predicted by GR. We call this the amplitude-phase consistency test and introduce a procedure for performing it using information from the ringdown signal. Lastly, we apply this test to the GW190521 event, using the multimodal ringdown parameters inferred by Capano et al. [arXiv:2105.05238]. While ringdown measurements errors for this event are large, we show that GW190521 is consistent with the amplitude-phase consistency test. Our test is particularly well suited for accommodating multiple loud ringdown detections as those expected in the near future, and can be used complementarily to standard black-hole spectroscopy as a proxy for modified gravity, compact objects other than black holes, binary precession and eccentricity.
Collapse
Affiliation(s)
- Xisco Jiménez Forteza
- Max Planck Institute for Gravitational Physics (Albert Einstein Institute), Callinstraße 38, 30167 Hannover, Germany
- Leibniz Universität Hannover, 30167 Hannover, Germany
| | - Swetha Bhagwat
- Dipartimento di Fisica, "Sapienza" Università di Roma e Sezione INFN Roma1, Piazzale Aldo Moro 5, 00185 Roma, Italy
- Institute for Gravitational Wave Astronomy and School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Sumit Kumar
- Max Planck Institute for Gravitational Physics (Albert Einstein Institute), Callinstraße 38, 30167 Hannover, Germany
- Leibniz Universität Hannover, 30167 Hannover, Germany
| | - Paolo Pani
- Dipartimento di Fisica, "Sapienza" Università di Roma e Sezione INFN Roma1, Piazzale Aldo Moro 5, 00185 Roma, Italy
| |
Collapse
|
169
|
Coates A, Ramazanoğlu FM. Coordinate Singularities of Self-Interacting Vector Field Theories. PHYSICAL REVIEW LETTERS 2023; 130:021401. [PMID: 36706386 DOI: 10.1103/physrevlett.130.021401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 12/22/2022] [Indexed: 06/18/2023]
Abstract
Self-interacting vectors are seeing a burst of interest where various groups demonstrated that the field evolution ends in finite time. Two nonequivalent criteria have been offered to identify this breakdown: (i) the vector constraint equation cannot be satisfied beyond a point where the breakdown occurs, (ii) the dynamics is governed by an effective metric that becomes singular at the breakdown. We show that (i) identifies a coordinate singularity, and can be removed by a change of coordinates. Hence, it does not signify a physical problem, and cannot determine the validity of a theory.
Collapse
Affiliation(s)
- Andrew Coates
- Department of Physics, Koç University, Rumelifeneri Yolu, 34450 Sariyer, Istanbul, Turkey
| | - Fethi M Ramazanoğlu
- Department of Physics, Koç University, Rumelifeneri Yolu, 34450 Sariyer, Istanbul, Turkey
| |
Collapse
|
170
|
Subhash S, Das S, Dey TN, Li Y, Davuluri S. Enhancing the force sensitivity of a squeezed light optomechanical interferometer. OPTICS EXPRESS 2023; 31:177-191. [PMID: 36606959 DOI: 10.1364/oe.476672] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 12/01/2022] [Indexed: 06/17/2023]
Abstract
Application of frequency-dependent squeezed vacuum improves the force sensitivity of an optomechanical interferometer beyond the standard quantum limit by a factor of e-r, where r is the squeezing parameter. In this work, we show that the application of squeezed light along with quantum back-action nullifying meter in an optomechanical cavity with mechanical mirror in middle configuration can enhance the sensitivity beyond the standard quantum limit by a factor of e-reff, where reff = r + ln(4Δ/ζ)/2, for 0 < ζ/Δ < 1, with ζ as the optomechanical cavity decay rate and Δ as the detuning between cavity eigenfrequency and driving field. The technique described in this work is restricted to frequencies much smaller than the resonance frequency of the mechanical mirror. We further studied the sensitivity as a function of temperature, mechanical mirror reflectivity, and input laser power.
Collapse
|
171
|
Qiao CK, Zhou M. The gravitational bending of acoustic Schwarzschild black hole. THE EUROPEAN PHYSICAL JOURNAL. C, PARTICLES AND FIELDS 2023; 83:271. [PMID: 37034131 PMCID: PMC10067517 DOI: 10.1140/epjc/s10052-023-11376-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/02/2022] [Accepted: 03/03/2023] [Indexed: 05/17/2023]
Abstract
Acoustic black hole is becoming an attractive topic in recent years, for it open-up new direction for experimental/observational explorations of black holes. In this work, the gravitational bending of acoustic Schwarzschild black hole is investigated. The gravitational deflection angle of particles traveling along null geodesics, weak gravitational lensing and Einstein ring for acoustic Schwarzschild black hole are carefully studied and analyzed. Particularly, in the calculation of gravitational deflection angle, we resort to two approaches-the Gauss-Bonnet theorem and the geodesic method. The results show that the gravitational bending effect in acoustic Schwarzschild black hole is enhanced, compared with conventional Schwarzschild black hole. This result indicates that the acoustic black holes may be more easily detectable in gravitational bending effects and weak gravitational lensing observations.
Collapse
Affiliation(s)
- Chen-Kai Qiao
- College of Science, Chongqing University of Technology, Banan, Chongqing, 400054 China
| | - Mi Zhou
- College of Science, Chongqing University of Technology, Banan, Chongqing, 400054 China
| |
Collapse
|
172
|
Kilohertz quasiperiodic oscillations in short gamma-ray bursts. Nature 2023; 613:253-256. [PMID: 36624293 DOI: 10.1038/s41586-022-05497-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Accepted: 10/31/2022] [Indexed: 01/11/2023]
Abstract
Short gamma-ray bursts (GRBs) are associated with binary neutron star mergers, which are multimessenger astronomical events that have been observed both in gravitational waves and in the multiband electromagnetic spectrum1. Depending on the masses of the stars in the binary and on details of their largely unknown equation of state, a dynamically evolving and short-lived neutron star may be formed after the merger, existing for approximately 10-300 ms before collapsing to a black hole2,3. Numerical relativity simulations across different groups consistently show broad power spectral features in the 1-5-kHz range in the post-merger gravitational-wave signal4-14, which is inaccessible by current gravitational-wave detectors but could be seen by future third-generation ground-based detectors in the next decade15-17. This implies the possibility of quasiperiodic modulation of the emitted gamma rays in a subset of events in which a neutron star is formed shortly before the final collapse to a black hole18-21. Here we present two such signals identified in the short bursts GRB 910711 and GRB 931101B from archival Burst and Transient Source Experiment (BATSE) data, which are compatible with the predictions from numerical relativity.
Collapse
|
173
|
González-Albaladejo R, Carpio A, Bonilla LL. Scale-free chaos in the confined Vicsek flocking model. Phys Rev E 2023; 107:014209. [PMID: 36797962 DOI: 10.1103/physreve.107.014209] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Accepted: 01/05/2023] [Indexed: 06/18/2023]
Abstract
The Vicsek model encompasses the paradigm of active dry matter. Motivated by collective behavior of insects in swarms, we have studied finite-size effects and criticality in the three-dimensional, harmonically confined Vicsek model. We have discovered a phase transition that exists for appropriate noise and small confinement strength. On the critical line of confinement versus noise, swarms are in a state of scale-free chaos characterized by minimal correlation time, correlation length proportional to swarm size and topological data analysis. The critical line separates dispersed single clusters from confined multicluster swarms. Scale-free chaotic swarms occupy a compact region of space and comprise a recognizable "condensed" nucleus and particles leaving and entering it. Susceptibility, correlation length, dynamic correlation function, and largest Lyapunov exponent obey power laws. The critical line and a narrow criticality region close to it move simultaneously to zero confinement strength for infinitely many particles. At the end of the first chaotic window of confinement, there is another phase transition to infinitely dense clusters of finite size that may be termed flocking black holes.
Collapse
Affiliation(s)
- R González-Albaladejo
- Departamento de Matemática Aplicada, Universidad Complutense de Madrid, 28040 Madrid, Spain
- Gregorio Millán Institute for Fluid Dynamics, Nanoscience and Industrial Mathematics, Universidad Carlos III de Madrid, 28911 Leganés, Spain
| | - A Carpio
- Departamento de Matemática Aplicada, Universidad Complutense de Madrid, 28040 Madrid, Spain
- Gregorio Millán Institute for Fluid Dynamics, Nanoscience and Industrial Mathematics, Universidad Carlos III de Madrid, 28911 Leganés, Spain
| | - L L Bonilla
- Gregorio Millán Institute for Fluid Dynamics, Nanoscience and Industrial Mathematics, Universidad Carlos III de Madrid, 28911 Leganés, Spain
- Department of Mathematics, Universidad Carlos III de Madrid, 28911 Leganés, Spain
| |
Collapse
|
174
|
Cooper SJ, Mow-Lowry CM, Hoyland D, Bryant J, Ubhi A, O'Dell J, Huddart A, Aston S, Vecchio A. Sensors and actuators for the advanced LIGO A+ upgrade. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2023; 94:014502. [PMID: 36725558 DOI: 10.1063/5.0117605] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2022] [Accepted: 12/21/2022] [Indexed: 06/18/2023]
Abstract
Advanced Laser Interferometer Gravitational-wave Observatory (LIGO A+) is a major upgrade to LIGO-the Laser Interferometer Gravitational-wave Observatory. For the A+ project, we have developed, produced, and characterized sensors and electronics to interrogate new optical suspensions designed to isolate optics from vibrations. The central element is a displacement sensor with an integrated electromagnetic actuator known as a BOSEM (Birmingham Optical Sensor and ElectroMagnetic actuator) and its readout and drive electronics required to integrate them into LIGO's control and data system. In this paper, we report on the improvements to the sensors and the testing procedures undertaken to meet the enhanced performance requirements set out by the A+ upgrade to the detectors. The best devices reach a noise level of 4.5 ×10-11m/Hz at a measurement frequency of 1 Hz, an improvement of 6.7 times over standard devices.
Collapse
Affiliation(s)
- S J Cooper
- Institute for Gravitational Wave Astronomy and School of Physics and Astronomy, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - C M Mow-Lowry
- Institute for Gravitational Wave Astronomy and School of Physics and Astronomy, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - D Hoyland
- Institute for Gravitational Wave Astronomy and School of Physics and Astronomy, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - J Bryant
- Institute for Gravitational Wave Astronomy and School of Physics and Astronomy, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - A Ubhi
- Institute for Gravitational Wave Astronomy and School of Physics and Astronomy, University of Birmingham, Birmingham B15 2TT, United Kingdom
| | - J O'Dell
- Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Campus, Didcot OX11 0QX, United Kingdom
| | - A Huddart
- Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Campus, Didcot OX11 0QX, United Kingdom
| | - S Aston
- LIGO Livingston Observatory, Livingston, Louisiana 70754, USA
| | - A Vecchio
- Institute for Gravitational Wave Astronomy and School of Physics and Astronomy, University of Birmingham, Birmingham B15 2TT, United Kingdom
| |
Collapse
|
175
|
Aniello P, Mancini S, Parisi V. A p-Adic Model of Quantum States and the p-Adic Qubit. ENTROPY (BASEL, SWITZERLAND) 2022; 25:86. [PMID: 36673227 PMCID: PMC9857597 DOI: 10.3390/e25010086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Revised: 12/26/2022] [Accepted: 12/27/2022] [Indexed: 06/17/2023]
Abstract
We propose a model of a quantum N-dimensional system (quNit) based on a quadratic extension of the non-Archimedean field of p-adic numbers. As in the standard complex setting, states and observables of a p-adic quantum system are implemented by suitable linear operators in a p-adic Hilbert space. In particular, owing to the distinguishing features of p-adic probability theory, the states of an N-dimensional p-adic quantum system are implemented by p-adic statistical operators, i.e., trace-one selfadjoint operators in the carrier Hilbert space. Accordingly, we introduce the notion of selfadjoint-operator-valued measure (SOVM)-a suitable p-adic counterpart of a POVM in a complex Hilbert space-as a convenient mathematical tool describing the physical observables of a p-adic quantum system. Eventually, we focus on the special case where N=2, thus providing a description of p-adic qubit states and 2-dimensional SOVMs. The analogies-but also the non-trivial differences-with respect to the qubit states of standard quantum mechanics are then analyzed.
Collapse
Affiliation(s)
- Paolo Aniello
- Dipartimento di Fisica “Ettore Pancini”, Università di Napoli “Federico II”, Complesso Universitario di Monte S. Angelo, Via Cintia, I-80126 Napoli, Italy
- Istituto Nazionale di Fisica Nucleare, Sezione di Napoli, Complesso Universitario di Monte S. Angelo, Via Cintia, I-80126 Napoli, Italy
| | - Stefano Mancini
- School of Science and Technology, University of Camerino, Via Madonna delle Carceri, 9, I-62032 Camerino, Italy
- Istituto Nazionale di Fisica Nucleare, Sezione di Perugia, Via A. Pascoli, I-06123 Perugia, Italy
| | - Vincenzo Parisi
- School of Science and Technology, University of Camerino, Via Madonna delle Carceri, 9, I-62032 Camerino, Italy
- Istituto Nazionale di Fisica Nucleare, Sezione di Perugia, Via A. Pascoli, I-06123 Perugia, Italy
| |
Collapse
|
176
|
Zilberman N, Casals M, Ori A, Ottewill AC. Quantum Fluxes at the Inner Horizon of a Spinning Black Hole. PHYSICAL REVIEW LETTERS 2022; 129:261102. [PMID: 36608207 DOI: 10.1103/physrevlett.129.261102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 10/09/2022] [Accepted: 11/28/2022] [Indexed: 06/17/2023]
Abstract
Rotating or charged classical black holes in isolation possess a special surface in their interior, the Cauchy horizon, beyond which the evolution of spacetime (based on the equations of General Relativity) ceases to be deterministic. In this Letter, we study the effect of a quantum massless scalar field on the Cauchy horizon inside a rotating (Kerr) black hole that is evaporating via the emission of Hawking radiation (corresponding to the field being in the Unruh state). We calculate the flux components (in Eddington coordinates) of the renormalized stress-energy tensor of the field on the Cauchy horizon, as functions of the black hole spin and of the polar angle. We find that these flux components are generically nonvanishing. Furthermore, we find that the flux components change sign as these parameters vary. The signs of the fluxes are important, as they provide an indication of whether the Cauchy horizon expands or crushes (when backreaction is taken into account). Regardless of these signs, our results imply that the flux components generically diverge on the Cauchy horizon when expressed in coordinates which are regular there. This is the first time that irregularity of the Cauchy horizon under a semiclassical effect is conclusively shown for (four-dimensional) spinning black holes.
Collapse
Affiliation(s)
- Noa Zilberman
- Department of Physics, Technion, Haifa 32000, Israel
| | - Marc Casals
- Institut für Theoretische Physik, Universität Leipzig, Brüderstrasse 16, Leipzig 04103, Germany
- Centro Brasileiro de Pesquisas Físicas (CBPF), Rio de Janeiro, CEP 22290-180, Brazil
- School of Mathematics and Statistics, University College Dublin, Belfield, Dublin 4, D04 V1W8, Ireland
- Laboratoire Univers et Théories, Observatoire de Paris, CNRS, Université PSL, Université de Paris, 92190 Meudon, France
| | - Amos Ori
- Department of Physics, Technion, Haifa 32000, Israel
| | - Adrian C Ottewill
- School of Mathematics and Statistics, University College Dublin, Belfield, Dublin 4, D04 V1W8, Ireland
| |
Collapse
|
177
|
Toroš M, Cromb M, Paternostro M, Faccio D. Generation of Entanglement from Mechanical Rotation. PHYSICAL REVIEW LETTERS 2022; 129:260401. [PMID: 36608206 DOI: 10.1103/physrevlett.129.260401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Revised: 10/01/2022] [Accepted: 10/24/2022] [Indexed: 06/17/2023]
Abstract
Many phenomena and fundamental predictions, ranging from Hawking radiation to the early evolution of the Universe rely on the interplay between quantum mechanics and gravity or more generally, quantum mechanics in curved spacetimes. However, our understanding is hindered by the lack of experiments that actually allow us to probe quantum mechanics in curved spacetime in a repeatable and accessible way. Here we propose an experimental scheme for a photon that is prepared in a path superposition state across two rotating Sagnac interferometers that have different diameters and thus represent a superposition of two different spacetimes. We predict the generation of genuine entanglement even at low rotation frequencies and show how these effects could be observed even due to the Earth's rotation. These predictions provide an accessible platform in which to study the role of the underlying spacetime in the generation of entanglement.
Collapse
Affiliation(s)
- Marko Toroš
- School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - Marion Cromb
- School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - Mauro Paternostro
- Centre for Quantum Materials and Technologies, School of Mathematics and Physics, Queen's University, Belfast BT7 1NN, United Kingdom
| | - Daniele Faccio
- School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| |
Collapse
|
178
|
Scott TC. From Modified Newtonian Dynamics to Superfluid Vacuum Theory. ENTROPY (BASEL, SWITZERLAND) 2022; 25:12. [PMID: 36673152 PMCID: PMC9857720 DOI: 10.3390/e25010012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 12/15/2022] [Accepted: 12/16/2022] [Indexed: 06/17/2023]
Abstract
Herein is a review of the essentials of Modified Newtonian Dynamics (MOND) versus dark matter models based on Superfluids for modeling galactic rotation curves. We review the successes and issues of both approaches. We then mention a recent alternative based on the Superfluid Vacuum Theory (SVT) with a nonlinear logarithmic Schrödinger equation (LogSE) which reconciles both approaches, retains the essential success of MOND and the Superfluid nature but does not necessitate the hypothesis of processes including dark matter. We conclude with the implications of this SVT alternative on quantum theory itself.
Collapse
Affiliation(s)
- Tony C Scott
- Institut für Physikalische Chemie, RWTH Aachen University, 52056 Aachen, Germany
| |
Collapse
|
179
|
Martin-Sanchez D, Li J, Marques DM, Zhang EZ, Munro PRT, Beard PC, Guggenheim JA. ABCD transfer matrix model of Gaussian beam propagation in Fabry-Perot etalons. OPTICS EXPRESS 2022; 30:46404-46417. [PMID: 36558595 PMCID: PMC10581742 DOI: 10.1364/oe.477563] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 11/20/2022] [Indexed: 06/17/2023]
Abstract
A numerical model of Gaussian beam propagation in planar Fabry-Perot (FP) etalons is presented. The model is based on the ABCD transfer matrix method. This method is easy to use and interpret, and readily connects models of lenses, mirrors, fibres and other optics to aid simulating complex multi-component etalon systems. To validate the etalon model, its predictions were verified using a previously validated model based on Fourier optics. To demonstrate its utility, three different etalon systems were simulated. The results suggest the model is valid and versatile and could aid in designing and understanding a range of systems containing planar FP etalons. The method could be extended to model higher order beams, other FP type devices such as plano-concave resonators, and more complex etalon systems such as those involving tilted components.
Collapse
Affiliation(s)
- David Martin-Sanchez
- Department of Medical Physics and Biomedical Engineering, University College London, UK
| | - Jing Li
- Department of Medical Physics and Biomedical Engineering, University College London, UK
| | - Dylan M. Marques
- Department of Medical Physics and Biomedical Engineering, University College London, UK
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, UK
| | - Edward Z. Zhang
- Department of Medical Physics and Biomedical Engineering, University College London, UK
- Wellcome / EPSRC Centre for Interventional and Surgical Sciences, University College London, UK
| | - Peter R. T. Munro
- Department of Medical Physics and Biomedical Engineering, University College London, UK
| | - Paul C. Beard
- Department of Medical Physics and Biomedical Engineering, University College London, UK
- Wellcome / EPSRC Centre for Interventional and Surgical Sciences, University College London, UK
| | - James A. Guggenheim
- Department of Medical Physics and Biomedical Engineering, University College London, UK
- Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, UK
- School of Computer Science, College of Engineering and Physical Sciences, University of Birmingham, UK
| |
Collapse
|
180
|
Deng H, Meng Y. Frequency Division Control of Line-of-Sight Tracking for Space Gravitational Wave Detector. SENSORS (BASEL, SWITZERLAND) 2022; 22:9721. [PMID: 36560090 PMCID: PMC9785843 DOI: 10.3390/s22249721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 11/24/2022] [Accepted: 12/06/2022] [Indexed: 06/17/2023]
Abstract
The space gravitational wave detector uses the inter-satellite laser interferometer to measure a change in distance with ultra-high precision at the picometer level. Its special differential wavefront sensing technology based on laser interference is used to obtain the ultra-high-precision relative attitude between spacecrafts. In order to acquire the measurement, it is necessary to maintain high-precision attitude pointing and alignment for the optical path line-of-sight of the detector. This paper proposes a frequency division control method. More specifically, we chose the telescope attitude control loop frequency division as it is the faster response part, mainly relative to the high-frequency band within the measurement bandwidth. The spacecraft attitude frequency division is mainly in the low-frequency band within the measurement bandwidth. Finally, a high-precision simulation analysis is carried out. The results show that compared with traditional methods, the use of frequency division control design can significantly improve the attitude and pointing stability of the system and provide control support for systems requiring high pointing coordination accuracy, such as space gravity wave detectors.
Collapse
Affiliation(s)
- Huifang Deng
- School of Physics and Astronomy, Sun Yat-sen University, Zhuhai 519082, China
| | - Yunhe Meng
- School of Artificial Intelligence, Sun Yat-sen University, Zhuhai 519082, China
| |
Collapse
|
181
|
Ochirov A, Skvortsov E. Chiral Approach to Massive Higher Spins. PHYSICAL REVIEW LETTERS 2022; 129:241601. [PMID: 36563270 DOI: 10.1103/physrevlett.129.241601] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Accepted: 11/10/2022] [Indexed: 06/17/2023]
Abstract
We propose a new, chiral description for massive higher-spin particles in four spacetime dimensions, which facilitates the introduction of consistent interactions. As proof of concept, we formulate three theories, in which higher-spin matter is coupled to electrodynamics, non-Abelian gauge theory, or gravity. The theories are chiral and have simple Lagrangians, resulting in Feynman rules analogous to those of massive scalars. Starting from these Feynman rules, we derive tree-level scattering amplitudes with two higher-spin matter particles and any number of positive-helicity photons, gluons, or gravitons. The amplitudes reproduce the arbitrary-multiplicity results that were obtained via on-shell recursion in a parity-conserving setting, and which chiral and nonchiral theories thus have in common. The presented theories are currently the only examples of consistent interacting field theories with massive higher-spin fields.
Collapse
Affiliation(s)
- Alexander Ochirov
- Mathematical Institute, University of Oxford, Woodstock Road, Oxford OX2 6GG, United Kingdom
| | - Evgeny Skvortsov
- Service de Physique de l'Univers, Champs et Gravitation, Université de Mons, 20 place du Parc, 7000 Mons, Belgium
- Lebedev Institute of Physics, Leninsky Avenue 53, 119991 Moscow, Russia
| |
Collapse
|
182
|
Antonopoulou D, Haskell B, Espinoza CM. Pulsar glitches: observations and physical interpretation. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2022; 85:126901. [PMID: 36279854 DOI: 10.1088/1361-6633/ac9ced] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Accepted: 10/24/2022] [Indexed: 06/16/2023]
Abstract
The interpretation of pulsar rotational glitches, the sudden increase in spin frequency of neutron stars, is a half-century-old challenge. The common view is that glitches are driven by the dynamics of the stellar interior, and connect in particular to the interactions between a large-scale neutron superfluid and the other stellar components. This thesis is corroborated by observational data of glitches and the post-glitch response seen in pulsars' rotation, which often involves very long timescales, from months to years. As such, glitch observables combined with consistent models incorporating the rich physics of neutron stars-from the lattice structure of their crust to the equation of state for matter beyond nuclear densities-can be very powerful at placing limits on, and reduce uncertainties of, the internal properties. This review summarises glitch observations, current data, and recent analyses, and connects them to the underlying mechanisms and microphysical parameters in the context of the most advanced theoretical glitch models to date.
Collapse
Affiliation(s)
- Danai Antonopoulou
- Jodrell Bank Centre for Astrophysics, School of Physics and Astronomy, University of Manchester, Manchester, M13 9PL, United Kingdom
| | - Brynmor Haskell
- Nicolaus Copernicus Astronomical Center of the Polish Academy of Sciences, Bartycka 18, 00-716 Warsaw, Poland
| | - Cristóbal M Espinoza
- Departamento de Física, Universidad de Santiago de Chile (USACH), Av. Victor Jara 3493, Estación Central, Chile
- Center for Interdisciplinary Research in Astrophysics and Space Sciences (CIRAS), Universidad de Santiago de Chile, Chile
| |
Collapse
|
183
|
A very luminous jet from the disruption of a star by a massive black hole. Nature 2022; 612:430-434. [PMID: 36450988 DOI: 10.1038/s41586-022-05465-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 10/19/2022] [Indexed: 12/02/2022]
Abstract
Tidal disruption events (TDEs) are bursts of electromagnetic energy that are released when supermassive black holes at the centres of galaxies violently disrupt a star that passes too close1. TDEs provide a window through which to study accretion onto supermassive black holes; in some rare cases, this accretion leads to launching of a relativistic jet2-9, but the necessary conditions are not fully understood. The best-studied jetted TDE so far is Swift J1644+57, which was discovered in γ-rays, but was too obscured by dust to be seen at optical wavelengths. Here we report the optical detection of AT2022cmc, a rapidly fading source at cosmological distance (redshift z = 1.19325) the unique light curve of which transitioned into a luminous plateau within days. Observations of a bright counterpart at other wavelengths, including X-ray, submillimetre and radio, supports the interpretation of AT2022cmc as a jetted TDE containing a synchrotron 'afterglow', probably launched by a supermassive black hole with spin greater than approximately 0.3. Using four years of Zwicky Transient Facility10 survey data, we calculate a rate of [Formula: see text] per gigapascals cubed per year for on-axis jetted TDEs on the basis of the luminous, fast-fading red component, thus providing a measurement complementary to the rates derived from X-ray and radio observations11. Correcting for the beaming angle effects, this rate confirms that approximately 1 per cent of TDEs have relativistic jets. Optical surveys can use AT2022cmc as a prototype to unveil a population of jetted TDEs.
Collapse
|
184
|
Mei A, Banerjee B, Oganesyan G, Salafia OS, Giarratana S, Branchesi M, D'Avanzo P, Campana S, Ghirlanda G, Ronchini S, Shukla A, Tiwari P. Gigaelectronvolt emission from a compact binary merger. Nature 2022; 612:236-239. [PMID: 36477131 DOI: 10.1038/s41586-022-05404-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Accepted: 10/03/2022] [Indexed: 12/12/2022]
Abstract
An energetic γ-ray burst (GRB), GRB 211211A, was observed on 11 December 20211,2. Despite its long duration, typically associated with bursts produced by the collapse of massive stars, the observation of an optical-infrared kilonova points to a compact binary merger origin3. Here we report observations of a significant (more than five sigma) transient-like emission in the high-energy γ-rays of GRB 211211A (more than 0.1 gigaelectronvolts) starting 103 seconds after the burst. After an initial phase with a roughly constant flux (about 5 × 10-10 erg per second per square centimetre) lasting about 2 × 104 seconds, the flux started decreasing and soon went undetected. Our detailed modelling of public and dedicated multi-wavelength observations demonstrates that gigaelectronvolt emission from GRB 211211A is in excess with respect to the flux predicted by the state-of-the-art afterglow model at such late time. We explore the possibility that the gigaelectronvolt excess is inverse Compton emission owing to the interaction of a late-time, low-power jet with an external source of photons, and find that kilonova emission can provide the seed photons. Our results open perspectives for observing binary neutron star mergers.
Collapse
Affiliation(s)
- Alessio Mei
- Gran Sasso Science Institute, L'Aquila, Italy.
- INFN - Laboratori Nazionali del Gran Sasso, L'Aquila, Italy.
| | - Biswajit Banerjee
- Gran Sasso Science Institute, L'Aquila, Italy
- INFN - Laboratori Nazionali del Gran Sasso, L'Aquila, Italy
| | - Gor Oganesyan
- Gran Sasso Science Institute, L'Aquila, Italy
- INFN - Laboratori Nazionali del Gran Sasso, L'Aquila, Italy
| | - Om Sharan Salafia
- Università degli Studi di Milano-Bicocca, Milan, Italy
- INFN - Sezione di Milano-Bicocca, Milan, Italy
- INAF - Osservatorio Astronomico di Brera, Merate, Italy
| | - Stefano Giarratana
- INAF - Istituto di Radioastronomia, Bologna, Italy
- Department of Physics and Astronomy, University of Bologna, Bologna, Italy
| | - Marica Branchesi
- Gran Sasso Science Institute, L'Aquila, Italy
- INFN - Laboratori Nazionali del Gran Sasso, L'Aquila, Italy
| | | | | | - Giancarlo Ghirlanda
- INFN - Sezione di Milano-Bicocca, Milan, Italy
- INAF - Osservatorio Astronomico di Brera, Merate, Italy
| | - Samuele Ronchini
- Gran Sasso Science Institute, L'Aquila, Italy
- INFN - Laboratori Nazionali del Gran Sasso, L'Aquila, Italy
| | - Amit Shukla
- Department of Astronomy, Astrophysics and Space Engineering, Indian Institute of Technology Indore, Indore, India
| | - Pawan Tiwari
- Department of Astronomy, Astrophysics and Space Engineering, Indian Institute of Technology Indore, Indore, India
| |
Collapse
|
185
|
Caldwell R, Cui Y, Guo HK, Mandic V, Mariotti A, No JM, Ramsey-Musolf MJ, Sakellariadou M, Sinha K, Wang LT, White G, Zhao Y, An H, Bian L, Caprini C, Clesse S, Cline JM, Cusin G, Fornal B, Jinno R, Laurent B, Levi N, Lyu KF, Martinez M, Miller AL, Redigolo D, Scarlata C, Sevrin A, Haghi BSE, Shu J, Siemens X, Steer DA, Sundrum R, Tamarit C, Weir DJ, Xie KP, Yang FW, Zhou S. Detection of early-universe gravitational-wave signatures and fundamental physics. GENERAL RELATIVITY AND GRAVITATION 2022; 54:156. [PMID: 36465478 PMCID: PMC9712380 DOI: 10.1007/s10714-022-03027-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Accepted: 10/20/2022] [Indexed: 06/17/2023]
Abstract
Detection of a gravitational-wave signal of non-astrophysical origin would be a landmark discovery, potentially providing a significant clue to some of our most basic, big-picture scientific questions about the Universe. In this white paper, we survey the leading early-Universe mechanisms that may produce a detectable signal-including inflation, phase transitions, topological defects, as well as primordial black holes-and highlight the connections to fundamental physics. We review the complementarity with collider searches for new physics, and multimessenger probes of the large-scale structure of the Universe.
Collapse
Affiliation(s)
- Robert Caldwell
- Department of Physics and Astronomy, Dartmouth College, Hanover, NH 03755 USA
| | - Yanou Cui
- Department of Physics and Astronomy, University of California, Riverside, CA 92521 USA
| | - Huai-Ke Guo
- Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 USA
| | - Vuk Mandic
- School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 USA
| | - Alberto Mariotti
- Theoretische Natuurkunde and IIHE/ELEM, Vrije Universiteit Brussel, and International Solvay Institutes, Pleinlaan 2, 1050 Brussels, Belgium
| | - Jose Miguel No
- Instituto de Física Teórica UAM/CSIC, C/ Nicolás Cabrera 13- 15, Campus de Cantoblanco, 28049 Madrid, Spain
| | - Michael J. Ramsey-Musolf
- Tsung Dao Lee Institute/Shanghai Jiao Tong University, Shanghai, 200120 People’s Republic of China
- University of Massachusetts, Amherst, MA 01003 USA
| | | | - Kuver Sinha
- Department of Physics and Astronomy, University of Oklahoma, Norman, OK 73019 USA
| | - Lian-Tao Wang
- Department of Physics, University of Chicago, Chicago, IL 60637 USA
| | - Graham White
- Kavli IPMU (WPI), UTIAS, The University of Tokyo, Kashiwa, Chiba 277-8583 Japan
| | - Yue Zhao
- Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 USA
| | - Haipeng An
- Department of Physics, Tsinghua University, Beijing, 100084 People’s Republic of China
- Center for High Energy Physics, Tsinghua University, Beijing, 100084 People’s Republic of China
- Center for High Energy Physics, Peking University, Beijing, 100871 People’s Republic of China
| | - Ligong Bian
- Center for High Energy Physics, Peking University, Beijing, 100871 People’s Republic of China
- Department of Physics and Chongqing Key Laboratory for Strongly Coupled Physics, Chongqing University, Chongqing, 401331 People’s Republic of China
| | - Chiara Caprini
- Theoretical Physics Department, University of Geneva, 1211 Geneva, Switzerland
- CERN, Theoretical Physics Department, 1 Esplanade des Particules, 1211 Genève 23, Switzerland
| | - Sebastien Clesse
- Service de Physique Théorique (CP225), University of Brussels (ULB), Boulevard du Triomphe, 1050 Brussels, Belgium
| | - James M. Cline
- Department of Physics, McGill University, Montréal, QC H3A2T8 Canada
| | - Giulia Cusin
- Theoretical Physics Department, University of Geneva, 1211 Geneva, Switzerland
- Sorbonne Université, CNRS, UMR 7095, Institut d’Astrophysique de Paris, 75014 Paris, France
| | - Bartosz Fornal
- Department of Chemistry and Physics, Barry University, Miami Shores, FL 33161 USA
| | - Ryusuke Jinno
- Instituto de Física Teórica UAM/CSIC, C/ Nicolás Cabrera 13- 15, Campus de Cantoblanco, 28049 Madrid, Spain
| | - Benoit Laurent
- Department of Physics, McGill University, Montréal, QC H3A2T8 Canada
| | - Noam Levi
- Raymond and Beverly Sackler School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv, 69978 Israel
| | - Kun-Feng Lyu
- School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 USA
| | - Mario Martinez
- Institut de Física d’Altes Energies, Barcelona Institute of Science and Technology and ICREA, 08193 Barcelona, Spain
| | - Andrew L. Miller
- Université catholique de Louvain, 1348 Louvain-la-Neuve, Belgium
| | - Diego Redigolo
- INFN, Sezione di Firenze Via G. Sansone 1, 50019 Sesto Fiorentino, Italy
| | - Claudia Scarlata
- School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 USA
| | - Alexander Sevrin
- Theoretische Natuurkunde and IIHE/ELEM, Vrije Universiteit Brussel, and International Solvay Institutes, Pleinlaan 2, 1050 Brussels, Belgium
| | - Barmak Shams Es Haghi
- Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 USA
| | - Jing Shu
- CAS Key Laboratory of Theoretical Physics, Insitute of Theoretical Physics, Chinese Academy of Sciences, Beijing, 100190 People’s Republic of China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing, 100049 People’s Republic of China
- School of Fundamental Physics and Mathematical Sciences, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou, 310024 People’s Republic of China
- International Center for Theoretical Physics Asia-Pacific, Beijing, Hanzhou, People’s Republic of China
| | - Xavier Siemens
- Department of Physics, Oregon State University, Corvallis, OR 97331 USA
| | - Danièle A. Steer
- Laboratoire Astroparticule et Cosmologie, CNRS, Université Paris Cité, 75013 Paris, France
| | | | - Carlos Tamarit
- Physik-Department T70, Technische Universität München, James-Franck-Straße, 85748 Garching, Germany
| | - David J. Weir
- Department of Physics and Helsinki Institute of Physics, University of Helsinki, P.O. Box 64, 00014 Helsinki, Finland
| | - Ke-Pan Xie
- Department of Physics and Astronomy, University of Nebraska, Lincoln, NE 68588 USA
| | - Feng-Wei Yang
- Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112 USA
| | - Siyi Zhou
- Department of Physics, Kobe University, Kobe, 657-8501 Japan
| |
Collapse
|
186
|
Dreissen LS, Yeh CH, Fürst HA, Grensemann KC, Mehlstäubler TE. Improved bounds on Lorentz violation from composite pulse Ramsey spectroscopy in a trapped ion. Nat Commun 2022; 13:7314. [DOI: 10.1038/s41467-022-34818-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Accepted: 11/08/2022] [Indexed: 11/28/2022] Open
Abstract
AbstractIn attempts to unify the four known fundamental forces in a single quantum-consistent theory, it is suggested that Lorentz symmetry may be broken at the Planck scale. Here we search for Lorentz violation at the low-energy limit by comparing orthogonally oriented atomic orbitals in a Michelson-Morley-type experiment. We apply a robust radiofrequency composite pulse sequence in the 2F7/2 manifold of an Yb+ ion, extending the coherence time from 200 μs to more than 1 s. In this manner, we fully exploit the high intrinsic susceptibility of the 2F7/2 state and take advantage of its exceptionally long lifetime. We match the stability of the previous best Lorentz symmetry test nearly an order of magnitude faster and improve the constraints on the symmetry breaking coefficients to the 10−21 level. These results represent the most stringent test of this type of Lorentz violation. The demonstrated method can be further extended to ion Coulomb crystals.
Collapse
|
187
|
A hybrid GNA instability. Sci Rep 2022; 12:19990. [PMID: 36411287 PMCID: PMC9678889 DOI: 10.1038/s41598-022-23854-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Accepted: 11/07/2022] [Indexed: 11/23/2022] Open
Abstract
A semi-analytic admixed model formalism to study the stability effects of the inner crust regions against the local collective perturbations in non-rotating neutron stars is proposed. It consists of the viscoelastic heavy neutron-rich nuclei, superfluid neutrons, and degenerate quantum electrons. A normal spherical mode analysis yields a generalized linear dispersion relation multiparametrically mimicking the inner crust features of neutron stars. A hybrid gravito-nucleo-acoustic (GNA) instability mode is found to be excited. It is demonstrated that the electron density and the inner crust curvature act as its accelerating and antidispersive agents. In contrast, the heavy neutron-rich nucleus and neutron densities act as decelerating factors. The heavy nucleus density, electron density, and geometric curvature act as its destabilizers. It is only the neutron density that acts as the GNA stabilizing agent. The heavy neutron-rich nucleus and neutron densities are found to act as dispersive broadening factors to it. The high-[Formula: see text] regions are the more unstable spectral windows indicating that the GNA mode plays a dominant role in the inner crust zone towards the local stability. Its fair reliability is indicated in light of the recent astronomic observed scenarios. It could be useful to explore acoustic mode signatures in non-rotating neutron stars and similar other compact astroobjects.
Collapse
|
188
|
Nalesso F, Rigato M, Cirella I, Protti MP, Zanella R, Rossi B, Putti MC, Martino FK, Calò LA. The Assessment of Renal Functional Reserve in β-Thalassemia Major Patients by an Innovative Ultrasound and Doppler Technique: A Pilot Study. J Clin Med 2022; 11:jcm11226752. [PMID: 36431228 PMCID: PMC9699445 DOI: 10.3390/jcm11226752] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2022] [Revised: 11/02/2022] [Accepted: 11/10/2022] [Indexed: 11/17/2022] Open
Abstract
Beta-thalassemia syndromes are the most common inherited monogenic disorders worldwide. The most common pathophysiologic and clinical renal disease manifestations of in β-TM patients is the tubular dysfunctions related to iron overload, chronic anemia, and the need for chronic iron chelation therapy. The aim of this pilot study is to apply an innovative ultrasound and Doppler technique to assess the Renal Functional Reserve (RFR) in β-TM patients, and to evaluate its reliability in iron overload tubulopathy. Ultrasound assessment of intra-parenchymal renal resistive index variation (IRRIV) has recently been proposed as a safe and reproducible technique to identify RFR presence. We define the preserved RFR when the Delta Renal Resistive Index (RRI) is >0.05 (baseline RRI—minimum RRI value during stress) in the Renal Stress Test (RST). Nineteen β-TM patients were enrolled for this study. In our series, we found a strong negative correlation between mean ferritin values and Delta RRI (R = −0.51, p = 0.03). This pilot study suggested the RST as reliable tool for assessing the RFR by ultrasound. Specifically, RST could help in clinical practice suggesting the patient’s management and iron chelation therapy.
Collapse
Affiliation(s)
- Federico Nalesso
- Department of Medicine, University of Padova, 35128 Padova, Italy
- Correspondence:
| | - Matteo Rigato
- Department of Medicine, University of Padova, 35128 Padova, Italy
| | - Irene Cirella
- Department of Medicine, University of Padova, 35128 Padova, Italy
| | | | - Ruggero Zanella
- Department of Medicine, University of Padova, 35128 Padova, Italy
| | - Bartolomeo Rossi
- Haematology-Oncology Clinic, Women and Child’s Health Department, University of Padua, 35122 Padua, Italy
| | - Maria Caterina Putti
- Haematology-Oncology Clinic, Women and Child’s Health Department, University of Padua, 35122 Padua, Italy
| | | | - Lorenzo A. Calò
- Department of Medicine, University of Padova, 35128 Padova, Italy
| |
Collapse
|
189
|
The 2+1-Dimensional Special Relativity. Symmetry (Basel) 2022. [DOI: 10.3390/sym14112403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
In the new mathematical description of special relativity in terms of the relativistic velocity space, many physical aspects acquire new geometric meanings. Performing conformal deformations upon the 2-dimensional relativistic velocity space for the (2+1)-dimensional special relativity, we find that these conformal deformations correspond to the generalized Lorentz transformations, which are akin to the ordinary Lorentz transformation, but are morphed by a global rescaling of the polar angle and correspondingly characterized by a topological integral index. The generalized Lorentz transformations keep the two fundamental principles of special relativity intact, suggesting that the indexed generalization may be related to the Bondi–Metzner–Sachs (BMS) group of the asymptotic symmetries of the spacetime metric. Furthermore, we investigate the Doppler effect of light, the Planck photon rocket, and the Thomas precession, affirming that they all remain in the same forms of the standard special relativity under the generalized Lorentz transformation. Additionally, we obtain the general formula of the Thomas precession, which gives a clear geometric meaning from the perspective of the gauge field theory in the relativistic velocity space.
Collapse
|
190
|
Weinfurtner S. Superfluid system hosts early-Universe dynamics. Nature 2022; 611:238-239. [DOI: 10.1038/d41586-022-03557-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
191
|
Bassi A, Cacciapuoti L, Capozziello S, Dell'Agnello S, Diamanti E, Giulini D, Iess L, Jetzer P, Joshi SK, Landragin A, Poncin-Lafitte CL, Rasel E, Roura A, Salomon C, Ulbricht H. A way forward for fundamental physics in space. NPJ Microgravity 2022; 8:49. [PMID: 36336703 PMCID: PMC9637703 DOI: 10.1038/s41526-022-00229-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Accepted: 10/03/2022] [Indexed: 11/08/2022] Open
Abstract
Space-based research can provide a major leap forward in the study of key open questions in the fundamental physics domain. They include the validity of Einstein's Equivalence principle, the origin and the nature of dark matter and dark energy, decoherence and collapse models in quantum mechanics, and the physics of quantum many-body systems. Cold-atom sensors and quantum technologies have drastically changed the approach to precision measurements. Atomic clocks and atom interferometers as well as classical and quantum links can be used to measure tiny variations of the space-time metric, elusive accelerations, and faint forces to test our knowledge of the physical laws ruling the Universe. In space, such instruments can benefit from unique conditions that allow improving both their precision and the signal to be measured. In this paper, we discuss the scientific priorities of a space-based research program in fundamental physics.
Collapse
Affiliation(s)
- A Bassi
- Department of Physics, University of Trieste, Strada Costiera 11, 34151, Trieste, Italy
- Istituto Nazionale di Fisica Nucleare, Trieste Section, Via Valerio 2, 34127, Trieste, Italy
| | - L Cacciapuoti
- European Space Agency, Keplerlaan 1 - P.O. Box 299, 2200 AG, Noordwijk, ZH, The Netherlands.
| | - S Capozziello
- Dipartimento di Fisica 'E. Pancini', Università di Napoli 'Federico II', INFN, Sezione di Napoli, via Cinthia 9, I-80126, Napoli, Italy
- Scuola Superiore Meridionale, Largo S. Marcellino 10, I-80138, Napoli, Italy
| | - S Dell'Agnello
- Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Frascati (INFN-LNF), via E. Fermi 54, 00044, Frascati (Rome), Italy
| | - E Diamanti
- LIP6, CNRS, Sorbonne Université, Paris, France
| | - D Giulini
- Institute for Theoretical Physics, Leibniz University Hannover, Appelstrasse 2, 30167, Hannover, Germany
| | - L Iess
- Sapienza Università di Roma, 00184, Rome, Italy
| | - P Jetzer
- Department of Physics, University of Zürich, Winterthurerstrasse 190, 8057, Zürich, Switzerland
| | - S K Joshi
- Quantum Engineering Technology Labs, H. H. Wills Physics Laboratory & Department of Electrical and Electronic Engineering, University of Bristol, Bristol, UK
| | - A Landragin
- SYRTE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, LNE, Paris, France
| | - C Le Poncin-Lafitte
- SYRTE, Observatoire de Paris, Université PSL, CNRS, Sorbonne Université, LNE, Paris, France
| | - E Rasel
- Leibniz Universität Hannover, Institut für Quantenoptik, Welfengarten 1, 30167, Hannover, Germany
| | - A Roura
- Institute of Quantum Technologies, German Aerospace Center (DLR), Wilhelm-Runge-Straße 10, 89081, Ulm, Germany
| | - C Salomon
- Laboratoire Kastler Brossel, ENS-Université PSL, CNRS, Sorbonne Université, Collège de France, Paris, France
| | - H Ulbricht
- School of Physics and Astronomy, University of Southampton, SO17 1BJ, Southampton, United Kingdom
| |
Collapse
|
192
|
Viermann C, Sparn M, Liebster N, Hans M, Kath E, Parra-López Á, Tolosa-Simeón M, Sánchez-Kuntz N, Haas T, Strobel H, Floerchinger S, Oberthaler MK. Quantum field simulator for dynamics in curved spacetime. Nature 2022; 611:260-264. [PMID: 36352135 DOI: 10.1038/s41586-022-05313-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 08/02/2022] [Indexed: 11/11/2022]
Abstract
In most cosmological models, rapid expansion of space marks the first moments of the Universe and leads to the amplification of quantum fluctuations1. The description of subsequent dynamics and related questions in cosmology requires an understanding of the quantum fields of the standard model and dark matter in curved spacetime. Even the reduced problem of a scalar quantum field in an explicitly time-dependent spacetime metric is a theoretical challenge2-5, and thus a quantum field simulator can lead to insights. Here we demonstrate such a quantum field simulator in a two-dimensional Bose-Einstein condensate with a configurable trap6,7 and adjustable interaction strength to implement this model system. We explicitly show the realization of spacetimes with positive and negative spatial curvature by wave-packet propagation and observe particle-pair production in controlled power-law expansion of space, using Sakharov oscillations to extract amplitude and phase information of the produced state. We find quantitative agreement with analytical predictions for different curvatures in time and space. This benchmarks and thereby establishes a quantum field simulator of a new class. In the future, straightforward upgrades offer the possibility to enter unexplored regimes that give further insight into relativistic quantum field dynamics.
Collapse
Affiliation(s)
- Celia Viermann
- Kirchhoff-Institut für Physik, Universität Heidelberg, Heidelberg, Germany.
| | - Marius Sparn
- Kirchhoff-Institut für Physik, Universität Heidelberg, Heidelberg, Germany
| | - Nikolas Liebster
- Kirchhoff-Institut für Physik, Universität Heidelberg, Heidelberg, Germany
| | - Maurus Hans
- Kirchhoff-Institut für Physik, Universität Heidelberg, Heidelberg, Germany
| | - Elinor Kath
- Kirchhoff-Institut für Physik, Universität Heidelberg, Heidelberg, Germany
| | - Álvaro Parra-López
- Institut für Theoretische Physik, Universität Heidelberg, Heidelberg, Germany.,Departamento de Física Teórica and IPARCOS, Facultad de Ciencias Físicas, Universidad Complutense de Madrid, Ciudad Universitaria, Madrid, Spain
| | - Mireia Tolosa-Simeón
- Institut für Theoretische Physik, Universität Heidelberg, Heidelberg, Germany.,Institut für Theoretische Physik III, Ruhr-Universität Bochum, Bochum, Germany
| | | | - Tobias Haas
- Institut für Theoretische Physik, Universität Heidelberg, Heidelberg, Germany.,Centre for Quantum Information and Communication, École polytechnique de Bruxelles, CP 165/59, Université libre de Bruxelles, Brussels, Belgium
| | - Helmut Strobel
- Kirchhoff-Institut für Physik, Universität Heidelberg, Heidelberg, Germany
| | - Stefan Floerchinger
- Institut für Theoretische Physik, Universität Heidelberg, Heidelberg, Germany.,Theoretisch-Physikalisches Institut, Friedrich-Schiller-Universität Jena, Jena, Germany
| | | |
Collapse
|
193
|
Foo J, Arabaci CS, Zych M, Mann RB. Quantum Signatures of Black Hole Mass Superpositions. PHYSICAL REVIEW LETTERS 2022; 129:181301. [PMID: 36374674 DOI: 10.1103/physrevlett.129.181301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Accepted: 09/16/2022] [Indexed: 06/16/2023]
Abstract
We present a new operational framework for studying "superpositions of spacetimes," which are of fundamental interest in the development of a theory of quantum gravity. Our approach capitalizes on nonlocal correlations in curved spacetime quantum field theory, allowing us to formulate a metric for spacetime superpositions as well as characterizing the coupling of particle detectors to a quantum field. We apply our approach to analyze the dynamics of a detector (using the Unruh-deWitt model) in a spacetime generated by a Banados-Teitelboim-Zanelli black hole in a superposition of masses. We find that the detector exhibits signatures of quantum-gravitational effects corroborating and extending Bekenstein's seminal conjecture concerning the quantized mass spectrum of black holes in quantum gravity. Crucially, this result follows directly from our approach, without any additional assumptions about the black hole mass properties.
Collapse
Affiliation(s)
- Joshua Foo
- Centre for Quantum Computation and Communication Technology, School of Mathematics and Physics, The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Cemile Senem Arabaci
- Department of Physics and Astronomy, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| | - Magdalena Zych
- Centre for Engineered Quantum Systems, School of Mathematics and Physics, The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Robert B Mann
- Perimeter Institute, 31 Caroline Street, Waterloo, Ontario N2L 2Y5, Canada
- Department of Astronomy, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada
| |
Collapse
|
194
|
Synchrotron Radiation Taking External Influences into Account. Symmetry (Basel) 2022. [DOI: 10.3390/sym14102207] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
In this paper, we demonstrate how various external forces influence the effect of the radiation of a charged particle. As a particular example, we obtained a solution to the Dirac equation for an electron in a constant homogeneous magnetic field and by taking into account the anomalous magnetic moment and influence of possible Lorentz invariance violation in minimal CPT-odd form. Based on the solution found, we calculated the synchrotron radiation (SR) characteristics and predicted possible observable effects attributable to the Lorentz invariance violation. As another example, we calculated the stimulated synchrotron radiation in the presence of the field of an electromagnetic wave and taking into account the inhomogeneity of an external magnetic field. Moreover, the superposition of two electromagnetic waves was also considered taking into account the properties of radiated electromagnetic waves. We also point out a way to use a corresponding semiclassical solution to the Dirac equation to obtain synchrotron radiation without approximating the radiative amplitudes themselves. This last way of calculating might be of use for studying SR in real circumstances of radiation in an astrophysical magnetic field and in electron accelerators, where electron trajectories are far from being circular.
Collapse
|
195
|
Toward a New Generation of Compact Transportable Yb+ Optical Clocks. Symmetry (Basel) 2022. [DOI: 10.3390/sym14102213] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Optical atomic clocks are currently one of the most sensitive tools making it possible to precisely test the fundamental symmetry properties of spacetime and Einstein’s theory of relativity. At the same time, the extremely high stability and accuracy of compact transportable optical clocks open new perspectives in important fields, such as satellite navigation, relativistic geodesy, and the global time and frequency network. Our project aimed to develop a compact transportable optical clock based on a single ytterbium ion. We present the first prototype of the Yb+ clock (298 kg in 1 m3) and present several solutions aimed to improve the clock’s robustness to approach the demands of a space-qualified system. We present spectroscopic studies of a 435.5 nm quadrupole clock transition with Fourier-limited spectra of 25 Hz. The estimated instability of the output frequency at 1 GHz, which was down-converted with an optical frequency comb (OFC), is at the level of 9×10−15/τ, and the long-term instability and inaccuracy are at the level of 5×10−16. As the next steps, we present a new design for the clock laser and the OFC.
Collapse
|
196
|
Mohageg M, Mazzarella L, Anastopoulos C, Gallicchio J, Hu BL, Jennewein T, Johnson S, Lin SY, Ling A, Marquardt C, Meister M, Newell R, Roura A, Schleich WP, Schubert C, Strekalov DV, Vallone G, Villoresi P, Wörner L, Yu N, Zhai A, Kwiat P. The deep space quantum link: prospective fundamental physics experiments using long-baseline quantum optics. EPJ QUANTUM TECHNOLOGY 2022; 9:25. [PMID: 36227029 PMCID: PMC9547810 DOI: 10.1140/epjqt/s40507-022-00143-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 09/15/2022] [Indexed: 06/16/2023]
Abstract
The National Aeronautics and Space Administration's Deep Space Quantum Link mission concept enables a unique set of science experiments by establishing robust quantum optical links across extremely long baselines. Potential mission configurations include establishing a quantum link between the Lunar Gateway moon-orbiting space station and nodes on or near the Earth. This publication summarizes the principal experimental goals of the Deep Space Quantum Link. These goals, identified through a multi-year design study conducted by the authors, include long-range teleportation, tests of gravitational coupling to quantum states, and advanced tests of quantum nonlocality.
Collapse
Affiliation(s)
- Makan Mohageg
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California USA
| | - Luca Mazzarella
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California USA
| | | | - Jason Gallicchio
- Department of Physics, Harvey Mudd College, Claremont, California USA
| | - Bei-Lok Hu
- Maryland Center for Fundamental Physics and Joint Quantum Institute, University of Maryland, College Park, Maryland USA
| | - Thomas Jennewein
- Institute for Quantum Computing and Dep. of Physics and Astronomy, University of Waterloo, Waterloo, Canada
| | - Spencer Johnson
- Department of Physics, Illinois Quantum Information Science & Technology Center, University of Illinois at Urbana-Champaign, Urbana, Illinois USA
| | - Shih-Yuin Lin
- Department of Physics, National Changhua University of Education, Changhua, Taiwan
| | - Alexander Ling
- Centre for Quantum Technologies and Department of Physics, National University of Singapore, Singapore, Singapore
| | | | - Matthias Meister
- Institute of Quantum Technologies, German Aerospace Center (DLR), Ulm, Germany
| | - Raymond Newell
- Los Alamos National Laboratory, Los Alamos, New Mexico USA
| | - Albert Roura
- Institute of Quantum Technologies, German Aerospace Center (DLR), Ulm, Germany
| | - Wolfgang P. Schleich
- Institute of Quantum Technologies, German Aerospace Center (DLR), Ulm, Germany
- Institut für Quantenphysik and Center for Integrated Quantum Science and Technology (IQst), Universität Ulm, Ulm, Germany
- Hagler Institute for Advanced Study, AgriLife Research, Institute for Quantum Science and Engineering (IQSE), and Department of Physics and Astronomy, Texas A& M University, College Station, Texas USA
| | - Christian Schubert
- Institute for Satellite Geodesy and Inertial Sensing, German Aerospace Center (DLR), Hanover, Germany
- Institute for Quantum Optics, Germany Leibniz University Hannover, Hanover, Germany
| | - Dmitry V. Strekalov
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California USA
| | - Giuseppe Vallone
- Dipartimento di Ingegneria dell’Informazione, Universitá degli Studi di Padova, Padova, Italy
- Padua Quantum Technologies Research Center, Universitá degli Studi di Padova, Padova, Italy
- Dipartimento di Fisica e Astronomia, Universitá degli Studi di Padova, Padova, Italy
| | - Paolo Villoresi
- Dipartimento di Ingegneria dell’Informazione, Universitá degli Studi di Padova, Padova, Italy
- Padua Quantum Technologies Research Center, Universitá degli Studi di Padova, Padova, Italy
| | - Lisa Wörner
- Institute of Quantum Technologies, German Aerospace Center (DLR), Ulm, Germany
| | - Nan Yu
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California USA
| | - Aileen Zhai
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California USA
| | - Paul Kwiat
- Department of Physics, University of Patras, Patras, Greece
| |
Collapse
|
197
|
Rosa JL, Rubiera-Garcia D. Shadows of boson and Proca stars with thin accretion disks. Int J Clin Exp Med 2022. [DOI: 10.1103/physrevd.106.084004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
198
|
Clough K, Helfer T, Witek H, Berti E. Ghost Instabilities in Self-Interacting Vector Fields: The Problem with Proca Fields. PHYSICAL REVIEW LETTERS 2022; 129:151102. [PMID: 36269968 DOI: 10.1103/physrevlett.129.151102] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 07/11/2022] [Accepted: 09/07/2022] [Indexed: 06/16/2023]
Abstract
Massive vector fields feature in several areas of particle physics, e.g., as carriers of weak interactions, dark matter candidates, or an effective description of photons in a plasma. Here, we investigate vector fields with self-interactions by replacing the mass term in the Proca equation with a general potential. We show that this seemingly benign modification inevitably introduces ghost instabilities of the same kind as those recently identified for vector-tensor theories of modified gravity (but in this simpler, minimally coupled theory). It has been suggested that nonperturbative dynamics may drive systems away from such instabilities. We demonstrate that this is not the case by evolving a self-interacting Proca field on a Kerr background, where it grows due to the superradiant instability. The system initially evolves as in the massive case, but instabilities are triggered in a finite time once the self-interaction becomes significant. These instabilities have implications for the formation of condensates of massive, self-interacting vector bosons, the possibility of spin-one bosenovae, vector dark matter models, and effective models for interacting photons in a plasma.
Collapse
Affiliation(s)
- Katy Clough
- School of Mathematical Sciences, Queen Mary University of London Mile End Road, London E1 4NS, United Kingdom
| | - Thomas Helfer
- Department of Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, USA
| | - Helvi Witek
- Illinois Center for Advanced Studies of the Universe, Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | - Emanuele Berti
- Department of Physics and Astronomy, Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, USA
| |
Collapse
|
199
|
Coates A, Ramazanoğlu FM. Intrinsic Pathology of Self-Interacting Vector Fields. PHYSICAL REVIEW LETTERS 2022; 129:151103. [PMID: 36269961 DOI: 10.1103/physrevlett.129.151103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 08/18/2022] [Accepted: 08/29/2022] [Indexed: 06/16/2023]
Abstract
We show that self-interacting vector field theories exhibit unphysical behavior even when they are not coupled to any external field. This means any theory featuring such vectors is in danger of being unphysical, an alarming prospect for many proposals in cosmology, gravity, high energy physics, and beyond. The problem arises when vector fields with healthy configurations naturally reach a point where time evolution is mathematically ill defined. We develop tools to easily identify this issue, and provide a simple and unifying framework to investigate it.
Collapse
Affiliation(s)
- Andrew Coates
- Department of Physics, Koç University, Rumelifeneri Yolu, 34450 Sariyer, Istanbul, Turkey
| | - Fethi M Ramazanoğlu
- Department of Physics, Koç University, Rumelifeneri Yolu, 34450 Sariyer, Istanbul, Turkey
| |
Collapse
|
200
|
Chen L. Can we "effectivize" spacetime? STUDIES IN HISTORY AND PHILOSOPHY OF SCIENCE 2022; 95:75-83. [PMID: 35985143 DOI: 10.1016/j.shpsa.2022.07.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2021] [Revised: 05/03/2022] [Accepted: 07/19/2022] [Indexed: 06/15/2023]
Abstract
According to effective realism, scientific theories give us knowledge about the unobservable world, but not at the fundamental level. This view is supported by the well-received effective-field-theory (EFT) approach to high energy physics, according to which even our most successful physical theories are only applicable up to a certain energy scale and expected to break down beyond that. In this paper, I advance new challenges for effective realism and the EFT approach. I argue that effective quantum gravity (EQG) does not give us a realistic theory of spacetime even within its scope of validity. This also exposes a general interpretative dilemma faced by all EFTs concerning their indispensable references to classical spacetime beyond their scope of validity.
Collapse
Affiliation(s)
- Lu Chen
- Koc University, Department of Philosophy, SOS 156, Istanbul 34450, Turkey.
| |
Collapse
|