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Mukherjee A, Gotur S, Aalberts J, van den Ende R, Mertens L, van Wezel J. Quantum State Reduction of General Initial States through Spontaneous Unitarity Violation. ENTROPY (BASEL, SWITZERLAND) 2024; 26:131. [PMID: 38392387 PMCID: PMC10887532 DOI: 10.3390/e26020131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 01/25/2024] [Accepted: 01/29/2024] [Indexed: 02/24/2024]
Abstract
The inability of Schrödinger's unitary time evolution to describe the measurement of a quantum state remains a central foundational problem. It was recently suggested that the unitarity of Schrödinger dynamics can be spontaneously broken, resulting in measurement as an emergent phenomenon in the thermodynamic limit. Here, we introduce a family of models for spontaneous unitarity violation that apply to generic initial superpositions over arbitrarily many states, using either single or multiple state-independent stochastic components. Crucially, we show that Born's probability rule emerges spontaneously in all cases.
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Affiliation(s)
- Aritro Mukherjee
- Institute for Theoretical Physics Amsterdam, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Srinivas Gotur
- Institute for Theoretical Physics Amsterdam, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Jelle Aalberts
- Institute for Theoretical Physics Amsterdam, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Rosa van den Ende
- Institute for Theoretical Physics Amsterdam, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Lotte Mertens
- Institute for Theoretical Physics Amsterdam, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
- Institute for Theoretical Solid State Physics, IFW Dresden, Helmholtzstr. 20, 01069 Dresden, Germany
| | - Jasper van Wezel
- Institute for Theoretical Physics Amsterdam, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
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2
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Snoke DW, Maienshein DN. Experimental Predictions for Norm-Conserving Spontaneous Collapse. ENTROPY (BASEL, SWITZERLAND) 2023; 25:1489. [PMID: 37998181 PMCID: PMC10670041 DOI: 10.3390/e25111489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2023] [Revised: 10/16/2023] [Accepted: 10/17/2023] [Indexed: 11/25/2023]
Abstract
Previous work has shown that nonlocal collapse in quantum mechanics can be described by a deterministic, non-unitary operator added to the standard Schrödinger equation. In terms of key aspects, this term differs from prior work on spontaneous collapse. In this paper, we discuss the possible predictions of this model that can be tested by experiments. This class of collapse model does not intrinsically imply unique experimental predictions, but it allows for the possibility.
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Affiliation(s)
- D. W. Snoke
- Department of Physics and Astronomy, University of Pittsburgh, 100 Allen Hall, Pittsburgh, PA 15260, USA
| | - D. N. Maienshein
- Department of Mathematics, University of Pittsburgh, 301 Thackeray Hall, Pittsburgh, PA 15260, USA;
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3
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Piscicchia K, Porcelli A, Bassi A, Bazzi M, Bragadireanu M, Cargnelli M, Clozza A, De Paolis L, Del Grande R, Derakhshani M, Lajos D, Donadi S, Guaraldo C, Iliescu M, Laubenstein M, Manti S, Marton J, Miliucci M, Napolitano F, Scordo A, Sgaramella F, Sirghi DL, Sirghi F, Vazquez Doce O, Zmeskal J, Curceanu C. A Novel Approach to Parameter Determination of the Continuous Spontaneous Localization Collapse Model. ENTROPY (BASEL, SWITZERLAND) 2023; 25:295. [PMID: 36832661 PMCID: PMC9955578 DOI: 10.3390/e25020295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 01/29/2023] [Accepted: 01/29/2023] [Indexed: 06/18/2023]
Abstract
Models of dynamical wave function collapse consistently describe the breakdown of the quantum superposition with the growing mass of the system by introducing non-linear and stochastic modifications to the standard Schrödinger dynamics. Among them, Continuous Spontaneous Localization (CSL) was extensively investigated both theoretically and experimentally. Measurable consequences of the collapse phenomenon depend on different combinations of the phenomenological parameters of the model-the strength λ and the correlation length rC-and have led, so far, to the exclusion of regions of the admissible (λ-rC) parameters space. We developed a novel approach to disentangle the λ and rC probability density functions, which discloses a more profound statistical insight.
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Affiliation(s)
- Kristian Piscicchia
- Centro Ricerche Enrico Fermi—Museo Storico della Fisica e Centro Studi e Ricerche “Enrico Fermi”, 00184 Rome, Italy
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
| | - Alessio Porcelli
- Centro Ricerche Enrico Fermi—Museo Storico della Fisica e Centro Studi e Ricerche “Enrico Fermi”, 00184 Rome, Italy
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
| | - Angelo Bassi
- Department of Physics, University of Trieste, 34127 Trieste, Italy
- Section of Trieste, Istituto Nazionale di Fisica Nucleare, 34149 Trieste, Italy
| | | | - Mario Bragadireanu
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
- IFIN-HH, Institutul National pentru Fizica si Inginerie Nucleara Horia Hulubei, 077125 Măgurele, Romania
| | - Michael Cargnelli
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
- Stefan-Meyer-Institute for Subatomic Physics, Austrian Academy of Science, 1030 Wien, Austria
| | - Alberto Clozza
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
| | - Luca De Paolis
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
| | - Raffaele Del Grande
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
- Excellence Cluster Universe, Technische Universität München, 80333 München, Germany
| | | | - Diósi Lajos
- Department of Physics of Complex Systems, Eötvös Loránd University, 1117 Budapest, Hungary
- Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, 1525 Budapest, Hungary
| | - Sandro Donadi
- Section of Trieste, Istituto Nazionale di Fisica Nucleare, 34149 Trieste, Italy
| | - Carlo Guaraldo
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
| | - Mihai Iliescu
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
| | | | - Simone Manti
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
| | - Johann Marton
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
- Stefan-Meyer-Institute for Subatomic Physics, Austrian Academy of Science, 1030 Wien, Austria
| | - Marco Miliucci
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
| | | | | | | | - Diana Laura Sirghi
- Centro Ricerche Enrico Fermi—Museo Storico della Fisica e Centro Studi e Ricerche “Enrico Fermi”, 00184 Rome, Italy
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
- IFIN-HH, Institutul National pentru Fizica si Inginerie Nucleara Horia Hulubei, 077125 Măgurele, Romania
| | - Florin Sirghi
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
- IFIN-HH, Institutul National pentru Fizica si Inginerie Nucleara Horia Hulubei, 077125 Măgurele, Romania
| | | | - Johann Zmeskal
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
- Stefan-Meyer-Institute for Subatomic Physics, Austrian Academy of Science, 1030 Wien, Austria
| | - Catalina Curceanu
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
- IFIN-HH, Institutul National pentru Fizica si Inginerie Nucleara Horia Hulubei, 077125 Măgurele, Romania
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4
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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] [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.
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5
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Arnquist IJ, Avignone FT, Barabash AS, Barton CJ, Bhimani KH, Blalock E, Bos B, Busch M, Buuck M, Caldwell TS, Chan YD, Christofferson CD, Chu PH, Clark ML, Cuesta C, Detwiler JA, Efremenko Y, Ejiri H, Elliott SR, Giovanetti GK, Green MP, Gruszko J, Guinn IS, Guiseppe VE, Haufe CR, Henning R, Hervas Aguilar D, Hoppe EW, Hostiuc A, Kim I, Kouzes RT, Lannen V TE, Li A, Lopez AM, López-Castaño JM, Martin EL, Martin RD, Massarczyk R, Meijer SJ, Oli TK, Othman G, Paudel LS, Pettus W, Poon AWP, Radford DC, Reine AL, Rielage K, Ruof NW, Tedeschi D, Varner RL, Vasilyev S, Wilkerson JF, Wiseman C, Xu W, Yu CH, Zhu BX. Search for Spontaneous Radiation from Wave Function Collapse in the Majorana Demonstrator. PHYSICAL REVIEW LETTERS 2022; 129:080401. [PMID: 36053678 DOI: 10.1103/physrevlett.129.080401] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 06/14/2022] [Accepted: 07/15/2022] [Indexed: 06/15/2023]
Abstract
The Majorana Demonstrator neutrinoless double-beta decay experiment comprises a 44 kg (30 kg enriched in ^{76}Ge) array of p-type, point-contact germanium detectors. With its unprecedented energy resolution and ultralow backgrounds, Majorana also searches for rare event signatures from beyond standard model physics in the low energy region below 100 keV. In this Letter, we test the continuous spontaneous localization (CSL) model, one of the mathematically well-motivated wave function collapse models aimed at solving the long-standing unresolved quantum mechanical measurement problem. While the CSL predicts the existence of a detectable radiation signature in the x-ray domain, we find no evidence of such radiation in the 19-100 keV range in a 37.5 kg-y enriched germanium exposure collected between December 31, 2015, and November 27, 2019, with the Demonstrator. We explored both the non-mass-proportional (n-m-p) and the mass-proportional (m-p) versions of the CSL with two different assumptions: that only the quasifree electrons can emit the x-ray radiation and that the nucleus can coherently emit an amplified radiation. In all cases, we set the most stringent upper limit to date for the white CSL model on the collapse rate, λ, providing a factor of 40-100 improvement in sensitivity over comparable searches. Our limit is the most stringent for large parts of the allowed parameter space. If the result is interpreted in terms of the Diòsi-Penrose gravitational wave function collapse model, the lower bound with a 95% confidence level is almost an order of magnitude improvement over the previous best limit.
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Affiliation(s)
- I J Arnquist
- Pacific Northwest National Laboratory, Richland, Washington 99354, USA
| | - F T Avignone
- Department of Physics and Astronomy, University of South Carolina, Columbia, South Carolina 29208, USA
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, USA
| | - A S Barabash
- National Research Center "Kurchatov Institute" Institute for Theoretical and Experimental Physics, Moscow, 117218 Russia
| | - C J Barton
- Department of Physics, University of South Dakota, Vermillion, South Dakota 57069, USA
| | - K H Bhimani
- Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27514, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - E Blalock
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
- Department of Physics, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - B Bos
- Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27514, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - M Busch
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
| | - M Buuck
- Center for Experimental Nuclear Physics and Astrophysics, and Department of Physics, University of Washington, Seattle, Washington 98195, USA
| | - T S Caldwell
- Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27514, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - Y-D Chan
- Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | | | - P-H Chu
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - M L Clark
- Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27514, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - C Cuesta
- Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas, CIEMAT 28040 Madrid, Spain
| | - J A Detwiler
- Center for Experimental Nuclear Physics and Astrophysics, and Department of Physics, University of Washington, Seattle, Washington 98195, USA
| | - Yu Efremenko
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, USA
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37916, USA
| | - H Ejiri
- Research Center for Nuclear Physics, Osaka University, Ibaraki, Osaka 567-0047, Japan
| | - S R Elliott
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - G K Giovanetti
- Physics Department, Williams College, Williamstown, Massachusetts 01267, USA
| | - M P Green
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
- Department of Physics, North Carolina State University, Raleigh, North Carolina 27695, USA
| | - J Gruszko
- Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27514, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - I S Guinn
- Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27514, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - V E Guiseppe
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, USA
| | - C R Haufe
- Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27514, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - R Henning
- Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27514, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - D Hervas Aguilar
- Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27514, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - E W Hoppe
- Pacific Northwest National Laboratory, Richland, Washington 99354, USA
| | - A Hostiuc
- Center for Experimental Nuclear Physics and Astrophysics, and Department of Physics, University of Washington, Seattle, Washington 98195, USA
| | - I Kim
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - R T Kouzes
- Pacific Northwest National Laboratory, Richland, Washington 99354, USA
| | - T E Lannen V
- Department of Physics and Astronomy, University of South Carolina, Columbia, South Carolina 29208, USA
| | - A Li
- Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27514, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - A M Lopez
- Department of Physics and Astronomy, University of Tennessee, Knoxville, Tennessee 37916, USA
| | | | - E L Martin
- Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27514, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - R D Martin
- Department of Physics, Engineering Physics and Astronomy, Queen's University, Kingston, Ontario K7L 3N6, Canada
| | - R Massarczyk
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - S J Meijer
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - T K Oli
- Department of Physics, University of South Dakota, Vermillion, South Dakota 57069, USA
| | - G Othman
- Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27514, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - L S Paudel
- Department of Physics, University of South Dakota, Vermillion, South Dakota 57069, USA
| | - W Pettus
- Department of Physics, Indiana University, Bloomington, Indiana 47405, USA
- IU Center for Exploration of Energy and Matter, Bloomington, Indiana 47408, USA
| | - A W P Poon
- Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - D C Radford
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, USA
| | - A L Reine
- Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27514, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - K Rielage
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - N W Ruof
- Center for Experimental Nuclear Physics and Astrophysics, and Department of Physics, University of Washington, Seattle, Washington 98195, USA
| | - D Tedeschi
- Department of Physics and Astronomy, University of South Carolina, Columbia, South Carolina 29208, USA
| | - R L Varner
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, USA
| | - S Vasilyev
- Joint Institute for Nuclear Research, Dubna, 141980 Russia
| | - J F Wilkerson
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, USA
- Department of Physics and Astronomy, University of North Carolina, Chapel Hill, North Carolina 27514, USA
- Triangle Universities Nuclear Laboratory, Durham, North Carolina 27708, USA
| | - C Wiseman
- Center for Experimental Nuclear Physics and Astrophysics, and Department of Physics, University of Washington, Seattle, Washington 98195, USA
| | - W Xu
- Department of Physics, University of South Dakota, Vermillion, South Dakota 57069, USA
| | - C-H Yu
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, USA
| | - B X Zhu
- Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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Zheng X, Liu Y, Qiu J, Liu G. Structural Optimization of Graphene Triangular Lattice Phononic Crystal Based on Dissipation Dilution Theory. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:2807. [PMID: 36014672 PMCID: PMC9415148 DOI: 10.3390/nano12162807] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 07/16/2022] [Accepted: 07/20/2022] [Indexed: 06/15/2023]
Abstract
Nanomechanical resonators offer brilliant mass and force sensitivity applied in many fields, owing to a low mass m and high-quality factor Q. However, in vibrating process, resonant energy is inevitably dissipated. Typically, quality factor does not surpass the inverse of the material loss angle φ. Recently, some exceptions emerged in the use of highly stressed silicon nitride material. As yet, it is interpreted that the pre-stress seems to "dilute" the intrinsic energy dissipation according to the Zener model. Is there any other material that could further break the 1/φ limit and achieve higher quality factors? In our previous research, through theoretical calculation and finite element simulation, we have proved that graphene's quality factor is two orders of magnitude larger than silicon nitride, on account of the extremely thin thickness of graphene. Based on this, we further optimize the structure of phononic crystals to achieve higher quality factors, in terms of duty cycle and cell size. Through simulation analysis, the quality factor could improve with a larger duty cycle and bigger cell size of triangular lattice phononic crystal. Unexpectedly, the Q amplification coefficient of the 3 × 5-cell structure, which is the least number to compose a phononic crystal with a central defect area, is the highest. In contrast, the minimal cell-number structure in hexagonal lattice could not achieve the brilliant dissipation dilution effect as well as the triangular one. Then we consider how overall size and stress influence quality factor and, furthermore, compare theoretical calculation and finite simulation. Lastly, we start from the primitive 3 × 5 cells, constantly adding cells to the periphery. Through simulation, to our surprise, the largest Q amplification coefficient does not belong to the largest structure, instead originating from the moderate one consisting of 7 × 13 cells.
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7
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Wang P. Relativistic quantum field theory of stochastic dynamics in the Hilbert space. Int J Clin Exp Med 2022. [DOI: 10.1103/physrevd.105.115037] [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]
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Gundhi A, Gaona-Reyes JL, Carlesso M, Bassi A. Impact of Dynamical Collapse Models on Inflationary Cosmology. PHYSICAL REVIEW LETTERS 2021; 127:091302. [PMID: 34506170 DOI: 10.1103/physrevlett.127.091302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 05/29/2021] [Accepted: 07/21/2021] [Indexed: 06/13/2023]
Abstract
Inflation solves several cosmological problems at the classical and quantum level, with a strong agreement between the theoretical predictions of well-motivated inflationary models and observations. In this Letter, we study the corrections induced by dynamical collapse models, which phenomenologically solve the quantum measurement problem, to the power spectrum of the comoving curvature perturbation during inflation and the radiation-dominated era. We find that the corrections are strongly negligible for the reference values of the collapse parameters.
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Affiliation(s)
- A Gundhi
- 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
| | - J L Gaona-Reyes
- 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
| | - M Carlesso
- Centre for Theoretical Atomic, Molecular, and Optical Physics, School of Mathematics and Physics, Queens University, Belfast BT7 1NN, United Kingdom
| | - 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
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9
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Pleinert MO, Rueda A, Lutz E, von Zanthier J. Testing Higher-Order Quantum Interference with Many-Particle States. PHYSICAL REVIEW LETTERS 2021; 126:190401. [PMID: 34047583 DOI: 10.1103/physrevlett.126.190401] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 02/18/2021] [Accepted: 04/12/2021] [Indexed: 06/12/2023]
Abstract
Quantum theory permits interference between indistinguishable paths but, at the same time, restricts its order. Single-particle interference, for instance, is limited to the second order, that is, to pairs of single-particle paths. To date, all experimental efforts to search for higher-order interferences beyond those compatible with quantum mechanics have been based on such single-particle schemes. However, quantum physics is not bound to single-particle interference. We here experimentally study many-particle higher-order interference using a two-photon-five-slit setup. We observe nonzero two-particle interference up to fourth order, corresponding to the interference of two distinct two-particle paths. We further show that fifth-order interference is restricted to 10^{-3} in the intensity-correlation regime and to 10^{-2} in the photon-correlation regime, thus providing novel bounds on higher-order quantum interference.
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Affiliation(s)
- Marc-Oliver Pleinert
- Institut für Optik, Information und Photonik, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91058 Erlangen, Germany
- Erlangen Graduate School in Advanced Optical Technologies (SAOT), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91052 Erlangen, Germany
| | - Alfredo Rueda
- Institut für Optik, Information und Photonik, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91058 Erlangen, Germany
| | - Eric Lutz
- Institute for Theoretical Physics I, University of Stuttgart, D-70550 Stuttgart, Germany
| | - Joachim von Zanthier
- Institut für Optik, Information und Photonik, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91058 Erlangen, Germany
- Erlangen Graduate School in Advanced Optical Technologies (SAOT), Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91052 Erlangen, Germany
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10
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Vinante A, Carlesso M, Bassi A, Chiasera A, Varas S, Falferi P, Margesin B, Mezzena R, Ulbricht H. Narrowing the Parameter Space of Collapse Models with Ultracold Layered Force Sensors. PHYSICAL REVIEW LETTERS 2020; 125:100404. [PMID: 32955323 DOI: 10.1103/physrevlett.125.100404] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Revised: 06/15/2020] [Accepted: 07/24/2020] [Indexed: 06/11/2023]
Abstract
Despite the unquestionable empirical success of quantum theory, witnessed by the recent uprising of quantum technologies, the debate on how to reconcile the theory with the macroscopic classical world is still open. Spontaneous collapse models are one of the few testable solutions so far proposed. In particular, the continuous spontaneous localization (CSL) model has become subject of intense experimental research. Experiments looking for the universal force noise predicted by CSL in ultrasensitive mechanical resonators have recently set the strongest unambiguous bounds on CSL. Further improving these experiments by direct reduction of mechanical noise is technically challenging. Here, we implement a recently proposed alternative strategy that aims at enhancing the CSL noise by exploiting a multilayer test mass attached on a high quality factor microcantilever. The test mass is specifically designed to enhance the effect of CSL noise at the characteristic length r_{c}=10^{-7} m. The measurements are in good agreement with pure thermal motion for temperatures down to 100 mK. From the absence of excess noise, we infer a new bound on the collapse rate at the characteristic length r_{c}=10^{-7} m, which improves over previous mechanical experiments by more than 1 order of magnitude. Our results explicitly challenge a well-motivated region of the CSL parameter space proposed by Adler.
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Affiliation(s)
- A Vinante
- Department of Physics and Astronomy, University of Southampton, Southampton SO17 1BJ, United Kingdom
- IFN-CNR and Fondazione Bruno Kessler, I-38123, Trento, Italy
| | - M Carlesso
- 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
| | - 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
| | - A Chiasera
- IFN-CNR CSMFO Lab and FBK Photonics Unit, I-38123 Trento, Italy
| | - S Varas
- IFN-CNR CSMFO Lab and FBK Photonics Unit, I-38123 Trento, Italy
| | - P Falferi
- IFN-CNR and Fondazione Bruno Kessler, I-38123, Trento, Italy
| | - B Margesin
- Fondazione Bruno Kessler-CMM, I-38123, Trento, Italy
| | - R Mezzena
- Department of Physics, University of Trento, I-38123, Trento, Italy
| | - H Ulbricht
- Department of Physics and Astronomy, University of Southampton, Southampton SO17 1BJ, United Kingdom
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11
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Goldwater D, Barker PF, Bassi A, Donadi S. Quantum Spectrometry for Arbitrary Noise. PHYSICAL REVIEW LETTERS 2019; 123:230801. [PMID: 31868443 DOI: 10.1103/physrevlett.123.230801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Indexed: 06/10/2023]
Abstract
We present a technique for recovering the spectrum of a non-Markovian bosonic bath and/or non-Markovian noises coupled to a harmonic oscillator. The treatment is valid under the conditions that the environment is large and hot compared to the oscillator, and that its temporal autocorrelation functions are symmetric with respect to time translation and reflection-criteria which we consider fairly minimal. We model a demonstration of the technique as deployed in the experimental scenario of a nanosphere levitated in a Paul trap, and show that it would effectively probe the spectrum of an electric field noise source from 10^{2} to 10^{6} Hz with a resolution inversely proportional to the measurement time. This technique may be deployed in quantum sensing, metrology, computing, and in experimental probes of foundational questions.
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Affiliation(s)
- Daniel Goldwater
- Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - P F Barker
- Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, United Kingdom
| | - Angelo Bassi
- Department of Physics, University of Trieste, Strada Costiera 11, 34151 Trieste, Italy and Istituto Nazionale di Fisica Nucleare, Trieste Section, Via Valerio 2, 34127 Trieste, Italy
| | - Sandro Donadi
- Frankfurt Institute for Advanced Studies (FIAS), Ruth-Moufang-Straße 1, 60438 Frankfurt am Main, Germany
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12
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Xu Z, García-Pintos LP, Chenu A, Del Campo A. Extreme Decoherence and Quantum Chaos. PHYSICAL REVIEW LETTERS 2019; 122:014103. [PMID: 31012673 DOI: 10.1103/physrevlett.122.014103] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Indexed: 06/09/2023]
Abstract
We study the ultimate limits to the decoherence rate associated with dephasing processes. Fluctuating chaotic quantum systems are shown to exhibit extreme decoherence, with a rate that scales exponentially with the particle number, thus exceeding the polynomial dependence of systems with fluctuating k-body interactions. Our findings suggest the use of quantum chaotic systems as a natural test bed for spontaneous wave function collapse models. We further discuss the implications on the decoherence of AdS/CFT black holes resulting from the unitarity loss associated with energy dephasing.
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Affiliation(s)
- Zhenyu Xu
- School of Physical Science and Technology, Soochow University, Suzhou 215006, China
- Department of Physics, University of Massachusetts, Boston, Massachusetts 02125, USA
| | | | - Aurélia Chenu
- Donostia International Physics Center, E-20018 San Sebastián, Spain
- IKERBASQUE, Basque Foundation for Science, E-48013 Bilbao, Spain
- Theoretical Division, Los Alamos National Laboratory, MS-B213, Los Alamos, New Mexico 87545, USA
| | - Adolfo Del Campo
- Department of Physics, University of Massachusetts, Boston, Massachusetts 02125, USA
- Donostia International Physics Center, E-20018 San Sebastián, Spain
- IKERBASQUE, Basque Foundation for Science, E-48013 Bilbao, Spain
- Theoretical Division, Los Alamos National Laboratory, MS-B213, Los Alamos, New Mexico 87545, USA
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