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Burrage C, Sakstein J. Tests of chameleon gravity. LIVING REVIEWS IN RELATIVITY 2018; 21:1. [PMID: 29576739 PMCID: PMC5856913 DOI: 10.1007/s41114-018-0011-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 02/06/2018] [Indexed: 06/08/2023]
Abstract
Theories of modified gravity, where light scalars with non-trivial self-interactions and non-minimal couplings to matter-chameleon and symmetron theories-dynamically suppress deviations from general relativity in the solar system. On other scales, the environmental nature of the screening means that such scalars may be relevant. The highly-nonlinear nature of screening mechanisms means that they evade classical fifth-force searches, and there has been an intense effort towards designing new and novel tests to probe them, both in the laboratory and using astrophysical objects, and by reinterpreting existing datasets. The results of these searches are often presented using different parametrizations, which can make it difficult to compare constraints coming from different probes. The purpose of this review is to summarize the present state-of-the-art searches for screened scalars coupled to matter, and to translate the current bounds into a single parametrization to survey the state of the models. Presently, commonly studied chameleon models are well-constrained but less commonly studied models have large regions of parameter space that are still viable. Symmetron models are constrained well by astrophysical and laboratory tests, but there is a desert separating the two scales where the model is unconstrained. The coupling of chameleons to photons is tightly constrained but the symmetron coupling has yet to be explored. We also summarize the current bounds on f(R) models that exhibit the chameleon mechanism (Hu and Sawicki models). The simplest of these are well constrained by astrophysical probes, but there are currently few reported bounds for theories with higher powers of R. The review ends by discussing the future prospects for constraining screened modified gravity models further using upcoming and planned experiments.
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Affiliation(s)
- Clare Burrage
- School of Physics and Astronomy, University of Nottingham, Nottingham, NG7 2RD UK
| | - Jeremy Sakstein
- Department of Physics and Astronomy, Center for Particle Cosmology, University of Pennsylvania, Philadelphia, PA 19104 USA
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Brax P. What makes the Universe accelerate? A review on what dark energy could be and how to test it. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2018; 81:016902. [PMID: 28936984 DOI: 10.1088/1361-6633/aa8e64] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Explaining the origin of the acceleration of the expansion of the Universe remains as challenging as ever. In this review, we present different approaches from dark energy to modified gravity. We also emphasize the quantum nature of the problem and the need for an explanation which should violate Weinberg's no go theorem. This might involve a self-tuning mechanism or the acausal sequestering of the vacuum energy. Laboratory tests of the coupling to matter of nearly massless scalar fields, which could be one of the features required to explain the cosmic acceleration, are also reviewed.
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Affiliation(s)
- Philippe Brax
- Institut de Physique Théorique, Université Paris-Saclay, CEA, CNRS, F-91191 Gif/Yvette Cedex, France
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Klimchitskaya G, Mostepanenko V. Constraints on axionlike particles and non-Newtonian gravity from measuring the difference of Casimir forces. Int J Clin Exp Med 2017. [DOI: 10.1103/physrevd.95.123013] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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4
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Rider AD, Moore DC, Blakemore CP, Louis M, Lu M, Gratta G. Search for Screened Interactions Associated with Dark Energy below the 100 μm Length Scale. PHYSICAL REVIEW LETTERS 2016; 117:101101. [PMID: 27636465 DOI: 10.1103/physrevlett.117.101101] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Indexed: 06/06/2023]
Abstract
We present the results of a search for unknown interactions that couple to mass between an optically levitated microsphere and a gold-coated silicon cantilever. The scale and geometry of the apparatus enable a search for new forces that appear at distances below 100 μm and which would have evaded previous searches due to screening mechanisms. The data are consistent with electrostatic backgrounds and place upper limits on the strength of new interactions at <0.1 fN in the geometry tested. For the specific example of a chameleon interaction with an inverse power law potential, these results exclude matter couplings β>5.6×10^{4} in the region of parameter space where the self-coupling Λ≳5 meV and the microspheres are not fully screened.
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Affiliation(s)
- Alexander D Rider
- Department of Physics, Stanford University, Stanford, California 94305, USA
| | - David C Moore
- Department of Physics, Stanford University, Stanford, California 94305, USA
| | | | - Maxime Louis
- Department of Physics, École Polytechnique, 91128 Palaiseau, France
| | - Marie Lu
- Department of Physics, Stanford University, Stanford, California 94305, USA
| | - Giorgio Gratta
- Department of Physics, Stanford University, Stanford, California 94305, USA
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Schlögel S, Clesse S, Füzfa A. Probing modified gravity with atom-interferometry: A numerical approach. Int J Clin Exp Med 2016. [DOI: 10.1103/physrevd.93.104036] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Hamilton P, Jaffe M, Haslinger P, Simmons Q, Müller H, Khoury J. Atom-interferometry constraints on dark energy. Science 2015; 349:849-51. [DOI: 10.1126/science.aaa8883] [Citation(s) in RCA: 185] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- P. Hamilton
- Department of Physics, 366 Le Conte Hall MS 7300, University of California–Berkeley, Berkeley, CA 94720, USA
| | - M. Jaffe
- Department of Physics, 366 Le Conte Hall MS 7300, University of California–Berkeley, Berkeley, CA 94720, USA
| | - P. Haslinger
- Department of Physics, 366 Le Conte Hall MS 7300, University of California–Berkeley, Berkeley, CA 94720, USA
| | - Q. Simmons
- Department of Physics, 366 Le Conte Hall MS 7300, University of California–Berkeley, Berkeley, CA 94720, USA
| | - H. Müller
- Department of Physics, 366 Le Conte Hall MS 7300, University of California–Berkeley, Berkeley, CA 94720, USA
- Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, CA 94720, USA
| | - J. Khoury
- Center for Particle Cosmology, Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104, USA
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8
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Abele H, Jenke T, Konrad G. Spectroscopy with cold and ultra-cold neutrons. EPJ WEB OF CONFERENCES 2015. [DOI: 10.1051/epjconf/20159305002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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9
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Ivanov A, Pitschmann M. Nonrelativistic approximation of the Dirac equation for slow fermions in static metric spacetimes. Int J Clin Exp Med 2014. [DOI: 10.1103/physrevd.90.045040] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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10
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Jenke T, Cronenberg G, Burgdörfer J, Chizhova LA, Geltenbort P, Ivanov AN, Lauer T, Lins T, Rotter S, Saul H, Schmidt U, Abele H. Gravity resonance spectroscopy constrains dark energy and dark matter scenarios. PHYSICAL REVIEW LETTERS 2014; 112:151105. [PMID: 24785025 DOI: 10.1103/physrevlett.112.151105] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/26/2013] [Indexed: 06/03/2023]
Abstract
We report on precision resonance spectroscopy measurements of quantum states of ultracold neutrons confined above the surface of a horizontal mirror by the gravity potential of Earth. Resonant transitions between several of the lowest quantum states are observed for the first time. These measurements demonstrate that Newton's inverse square law of gravity is understood at micron distances on an energy scale of 10-14 eV. At this level of precision, we are able to provide constraints on any possible gravitylike interaction. In particular, a dark energy chameleon field is excluded for values of the coupling constant β>5.8×108 at 95% confidence level (C.L.), and an attractive (repulsive) dark matter axionlike spin-mass coupling is excluded for the coupling strength gsgp>3.7×10-16 (5.3×10-16) at a Yukawa length of λ=20 μm (95% C.L.).
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Affiliation(s)
- T Jenke
- Atominstitut, Technische Universität Wien, Stadionallee 2, 1020 Wien, Austria
| | - G Cronenberg
- Atominstitut, Technische Universität Wien, Stadionallee 2, 1020 Wien, Austria
| | - J Burgdörfer
- Institute for Theoretical Physics, Vienna University of Technology, Wiedner Hauptstraße 8-10, 1040 Vienna, Austria
| | - L A Chizhova
- Institute for Theoretical Physics, Vienna University of Technology, Wiedner Hauptstraße 8-10, 1040 Vienna, Austria
| | - P Geltenbort
- Institut Laue-Langevin, BP 156, 6 Rue Jules Horowitz, 38042 Grenoble Cedex 9, France
| | - A N Ivanov
- Atominstitut, Technische Universität Wien, Stadionallee 2, 1020 Wien, Austria
| | - T Lauer
- FRM II, Technische Universität München, Lichtenbergstraße 1, 85748 Garching, Germany
| | - T Lins
- Atominstitut, Technische Universität Wien, Stadionallee 2, 1020 Wien, Austria
| | - S Rotter
- Institute for Theoretical Physics, Vienna University of Technology, Wiedner Hauptstraße 8-10, 1040 Vienna, Austria
| | - H Saul
- Atominstitut, Technische Universität Wien, Stadionallee 2, 1020 Wien, Austria
| | - U Schmidt
- Physikalisches Institut, Universität Heidelberg, Im Neuenheimer Feld 226, 69120 Heidelberg, Germany
| | - H Abele
- Atominstitut, Technische Universität Wien, Stadionallee 2, 1020 Wien, Austria
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12
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Erickcek AL, Barnaby N, Burrage C, Huang Z. Catastrophic consequences of kicking the chameleon. PHYSICAL REVIEW LETTERS 2013; 110:171101. [PMID: 23679701 DOI: 10.1103/physrevlett.110.171101] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Indexed: 06/02/2023]
Abstract
The physics of the "dark energy" that drives the current cosmological acceleration remains mysterious, and the dark sector may involve new light dynamical fields. If these light scalars couple to matter, a screening mechanism must prevent them from mediating an unacceptably strong fifth force locally. Here we consider a concrete example: the chameleon mechanism. We show that the same coupling between the chameleon field and matter employed by the screening mechanism also has catastrophic consequences for the chameleon during the Universe's first minutes. The chameleon couples to the trace of the stress-energy tensor, which is temporarily nonzero in a radiation-dominated universe whenever a particle species becomes nonrelativistic. These "kicks" impart a significant velocity to the chameleon field, causing its effective mass to vary nonadiabatically and resulting in the copious production of quantum fluctuations. Dissipative effects strongly modify the background evolution of the chameleon field, invalidating all previous classical treatments of chameleon cosmology. Moreover, the resulting fluctuations have extremely high characteristic energies, which casts serious doubt on the validity of the effective theory. Our results demonstrate that quantum particle production can profoundly affect scalar-tensor gravity, a possibility not previously considered. Working in this new context, we also develop the theory and numerics of particle production in the regime of strong dissipation.
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Affiliation(s)
- Adrienne L Erickcek
- CITA, University of Toronto, 60 St. George Street, Toronto, Ontario M5S 3H8, Canada.
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Upadhye A. Symmetron dark energy in laboratory experiments. PHYSICAL REVIEW LETTERS 2013; 110:031301. [PMID: 23373910 DOI: 10.1103/physrevlett.110.031301] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Revised: 12/19/2012] [Indexed: 06/01/2023]
Abstract
The symmetron scalar field is a matter-coupled dark energy candidate which effectively decouples from matter in high-density regions through a symmetry restoration. We consider a previously unexplored regime, in which the vacuum mass μ~2.4×10(-3) eV of the symmetron is near the dark energy scale, and the matter coupling parameter M~1 TeV is just beyond standard model energies. Such a field will give rise to a fifth force at submillimeter distances which can be probed by short-range gravity experiments. We show that a torsion pendulum experiment such as Eöt-Wash can exclude symmetrons in this regime for all self-couplings λ is < or approximately equal to 7.5.
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Affiliation(s)
- Amol Upadhye
- High Energy Physics Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
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14
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Wang J, Hui L, Khoury J. No-go theorems for generalized chameleon field theories. PHYSICAL REVIEW LETTERS 2012; 109:241301. [PMID: 23368302 DOI: 10.1103/physrevlett.109.241301] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Indexed: 06/01/2023]
Abstract
The chameleon, or generalizations thereof, is a light scalar that couples to matter with gravitational strength, but whose manifestation depends on the ambient matter density. A key feature is that the screening mechanism suppressing its effects in high-density environments is determined by the local scalar field value. Under very general conditions, we prove two theorems limiting its cosmological impact: (i) the Compton wavelength of such a scalar can be at most ~/= 1 MPc at the present cosmic density, which restricts its impact to nonlinear scales; and (ii) the conformal factor relating Einstein- and Jordan-frame scale factors is essentially constant over the last Hubble time, which precludes the possibility of self-acceleration. These results imply that chameleonlike scalar fields have a negligible effect on the linear-scale growth history; theories that invoke a chameleonlike scalar to explain cosmic acceleration rely on a form of dark energy rather than a genuine modified gravity effect. Our analysis applies to a broad class of chameleon, symmetron, and dilaton theories.
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Affiliation(s)
- Junpu Wang
- Physics Department and Institute for Strings, Cosmology and Astroparticle Physics, Columbia University, New York, NY 10027, USA
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15
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Brax P, Pignol G. Strongly coupled chameleons and the neutronic quantum bouncer. PHYSICAL REVIEW LETTERS 2011; 107:111301. [PMID: 22026655 DOI: 10.1103/physrevlett.107.111301] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Indexed: 05/31/2023]
Abstract
We consider the potential detection of chameleons using bouncing ultracold neutrons. We show that the presence of a chameleon field over a planar plate would alter the energy levels of ultracold neutrons in the terrestrial gravitational field. When chameleons are strongly coupled to nuclear matter, β≳10(8), we find that the shift in energy levels would be detectable with the forthcoming GRANIT experiment, where a sensitivity of the order of 1% of a peV is expected. We also find that an extremely large coupling β≳10(11) would lead to new bound states at a distance of order 2 μm, which is already ruled out by previous Grenoble experiments. The resulting bound, β≲10(11), is already 3 orders of magnitude better than the upper bound, β≲10(14), from precision tests of atomic spectra.
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Affiliation(s)
- Philippe Brax
- Institut de Physique Théorique, CEA, IPhT, CNRS, URA 2306, F-91191Gif/Yvette Cedex, France.
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17
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Mota DF, Salzano V, Capozziello S. Testing feasibility of scalar-tensor gravity by scale dependent mass and coupling to matter. Int J Clin Exp Med 2011. [DOI: 10.1103/physrevd.83.084038] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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18
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Steffen JH, Upadhye A, Baumbaugh A, Chou AS, Mazur PO, Tomlin R, Weltman A, Wester W. Laboratory constraints on chameleon dark energy and power-law fields. PHYSICAL REVIEW LETTERS 2010; 105:261803. [PMID: 21231645 DOI: 10.1103/physrevlett.105.261803] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/11/2010] [Indexed: 05/30/2023]
Abstract
We report results from a search for chameleon particles created via photon-chameleon oscillations within a magnetic field. This experiment is sensitive to a wide class of unexplored chameleon power-law and dark energy models. These results exclude 5 orders of magnitude in the coupling of chameleons to photons covering a range of 4 orders of magnitude in chameleon effective mass and, for individual models, exclude between 4 and 12 orders of magnitude in chameleon couplings to matter.
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Affiliation(s)
- J H Steffen
- Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA
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Hinterbichler K, Khoury J. Screening long-range forces through local symmetry restoration. PHYSICAL REVIEW LETTERS 2010; 104:231301. [PMID: 20867225 DOI: 10.1103/physrevlett.104.231301] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2010] [Indexed: 05/27/2023]
Abstract
We present a screening mechanism that allows a scalar field to mediate a long-range (∼Mpc) force of gravitational strength in the cosmos while satisfying local tests of gravity. The mechanism hinges on local symmetry restoration in the presence of matter. In regions of sufficiently high matter density, the field is drawn towards ϕ = 0 where its coupling to matter vanishes and the ϕ → -ϕ symmetry is restored. In regions of low density, however, the symmetry is spontaneously broken, and the field couples to matter with gravitational strength. We predict deviations from general relativity in the solar system that are within reach of next-generation experiments, as well as astrophysically observable violations of the equivalence principle. The model can be distinguished experimentally from Brans-Dicke gravity, chameleon theories and brane-world modifications of gravity.
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Affiliation(s)
- Kurt Hinterbichler
- Center for Particle Cosmology, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
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Chou AS, Wester W, Baumbaugh A, Gustafson HR, Irizarry-Valle Y, Mazur PO, Steffen JH, Tomlin R, Upadhye A, Weltman A, Yang X, Yoo J. Search for chameleon particles using a photon-regeneration technique. PHYSICAL REVIEW LETTERS 2009; 102:030402. [PMID: 19257328 DOI: 10.1103/physrevlett.102.030402] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2008] [Indexed: 05/27/2023]
Abstract
We report the first results from the GammeV search for chameleon particles, which may be created via photon-photon interactions within a strong magnetic field. Chameleons are hypothesized scalar fields that could explain the dark energy problem. We implement a novel technique to create and trap the reflective particles within a jar and to detect them later via their afterglow as they slowly convert back into photons. These measurements provide the first experimental constraints on the couplings of chameleons to photons.
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Affiliation(s)
- A S Chou
- Center for Cosmology and Particle Physics, New York University, 4 Washington Place, New York, New York 10003, USA
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Li B, Barrow JD, Mota DF, Zhao H. Testing alternative theories of dark matter with the CMB. Int J Clin Exp Med 2008. [DOI: 10.1103/physrevd.78.064021] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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22
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Afanasev A, Baker OK, Beard KB, Biallas G, Boyce J, Minarni M, Ramdon R, Shinn M, Slocum P. Experimental limit on optical-photon coupling to light neutral scalar bosons. PHYSICAL REVIEW LETTERS 2008; 101:120401. [PMID: 18851343 DOI: 10.1103/physrevlett.101.120401] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2008] [Indexed: 05/26/2023]
Abstract
We report on the first results of a sensitive search for scalar coupling of photons to a light neutral boson in the mass range of approximately 1.0 meV (milli-electron volts) and coupling strength greater than 10(-6) GeV(-1) using optical photons. This was a photon regeneration experiment using the "light shining through a wall" technique in which laser light was passed through a strong magnetic field upstream of an optical beam dump; regenerated laser light was then searched for downstream of a second magnetic field region optically shielded from the former. Our results show no evidence for scalar coupling in this region of parameter space.
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Affiliation(s)
- A Afanasev
- Department of Physics, Hampton University, Hampton, VA 23668, USA
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Avelino PP, Beça LMG, Martins CJAP. Clustering properties of dynamical dark energy models. Int J Clin Exp Med 2008. [DOI: 10.1103/physrevd.77.101302] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Füzfa A, Alimi JM. Toward a unified description of dark energy and dark matter from the abnormally weighting energy hypothesis. Int J Clin Exp Med 2007. [DOI: 10.1103/physrevd.75.123007] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Adelberger EG, Heckel BR, Hoedl S, Hoyle CD, Kapner DJ, Upadhye A. Particle-physics implications of a recent test of the gravitational inverse-square law. PHYSICAL REVIEW LETTERS 2007; 98:131104. [PMID: 17501180 DOI: 10.1103/physrevlett.98.131104] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2007] [Indexed: 05/15/2023]
Abstract
We use data from our recent search for violations of the gravitational inverse-square law to constrain dilaton, radion, and chameleon exchange forces as well as arbitrary vector or scalar Yukawa interactions. We test the interpretation of the PVLAS Collaboration effect and a conjectured "fat-graviton" scenario and constrain the gamma_{5} couplings of pseuodscalar bosons and arbitrary power-law interactions.
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Affiliation(s)
- E G Adelberger
- Center for Experimental Nuclear Physics and Astrophysics, Box 354290, University of Washington, Seattle, WA 98195-4290, USA
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