Varying constants, Gravitation and Cosmology

Abstract

Fundamental constants are a cornerstone of our physical laws. Any constant varying in space and/or time would reflect the existence of an almost massless field that couples to matter. This will induce a violation of the universality of free fall. It is thus of utmost importance for our understanding of gravity and of the domain of validity of general relativity to test for their constancy. We thus detail the relations between the constants, the tests of the local position invariance and of the universality of free fall. We then review the main experimental and observational constraints that have been obtained from atomic clocks, the Oklo phenomenon, Solar system observations, meteorites dating, quasar absorption spectra, stellar physics, pulsar timing, the cosmic microwave background and big bang nucleosynthesis. At each step we describe the basics of each system, its dependence with respect to the constants, the known systematic effects and the most recent constraints that have been obtained. We then describe the main theoretical frameworks in which the low-energy constants may actually be varying and we focus on the unification mechanisms and the relations between the variation of different constants. To finish, we discuss the more speculative possibility of understanding their numerical values and the apparent fine-tuning that they confront us with.

145 pages, 10 figures, Review for Living Reviews in Relativity

References in corpus (102)

• Five-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Cosmological Interpretation
• Cosmology at Low Frequencies: The 21 cm Transition and the High-Redshift Universe
• Test of the Equivalence Principle Using a Rotating Torsion Balance
• Environmental Dependence of Masses and Coupling Constants
• A Bitter Pill: The Primordial Lithium Problem Worsens
• New Limits on Coupling of Fundamental Constants to Gravity Using ${}^{87}$Sr Optical Lattice Clocks
• Equivalence Principle Violations and Couplings of a Light Dilaton
• Enhanced effect of temporal variation of the fine structure constant in diatomic molecules
• Effects of rotation on the evolution of primordial stars
• First stars VII. Lithium in extremely metal poor dwarfs
• Enhanced sensitivity to variation of the fine structure constant and m_p/m_e in diatomic molecules
• Stability of the proton-to-electron mass ratio
• Enhanced laboratory sensitivity to variation of the fine-structure constant using highly-charged ions
• Coupled Variations of Fundamental Couplings and Primordial Nucleosynthesis
• Growing Matter
• Time drift of cosmological redshifts as a test of the Copernican principle
• The Barbero-Immirzi Parameter as a Scalar Field: K-Inflation from Loop Quantum Gravity?
• Probing String Theory with Modulated Cosmological Fluctuations
• The acceleration of the universe and the physics behind it
• The 21cm angular-power spectrum from the dark ages
• Strong Limit on a Variable Proton-to-Electron Mass Ratio from Molecules in the Distant Universe
• Growing neutrinos and cosmological selection
• Enhanced sensitivity to time-variation of m_p/m_e in the inversion spectrum of ammonia
• Quantum Physics Exploring Gravity in the Outer Solar System: The Sagas Project
• Interaction of the Barbero--Immirzi Field with Matter and Pseudo-Scalar Perturbations
• Revision of VLT/UVES constraints on a varying fine-structure constant
• Phenomenology of the Equivalence Principle with Light Scalars
• Dependence of nuclear binding on hadronic mass variation
• Comment on "Limits on the Time Variation of the Electromagnetic Fine-Structure Constant in the Low Energy Limit from Absorption Lines in the Spectra of Distant Quasars"
• Selection of ThAr lines for wavelength calibration of echelle spectra and implications for variations in the fine-structure constant
• Limit on the Temporal Variation of the Fine-Structure Constant Using Atomic Dysprosium
• Primordial nucleosynthesis as a probe of fundamental physics parameters
• Time-variability of alpha from realistic models of Oklo reactors
• A new measure of Delta alpha/alpha at redshift z = 1.84 from very high resolution spectra of Q1101-264
• UVES radial velocity accuracy from asteroid observations. Implications for the fine structure constant variability
• Evidence for the Multiverse in the Standard Model and Beyond
• Bounds on the fine structure constant variability from FeII absorption lines in QSO spectra
• Stars In Other Universes: Stellar structure with different fundamental constants
• Enhanced effect of quark mass variation in 229Th and limits from Oklo data
• Reconstructing the dark energy equation of state with varying couplings
• Unveiling Chameleons in Tests of Gravitational Inverse-Square Law
• The History of Nuclidic Masses and of their Evaluation
• Enhancement of variation of fundamental constants in ultracold atom and molecule systems near Feshbach resonances
• Cosmic microwave background bispectrum on small angular scales
• Constraints on the variability of quark masses from nuclear binding
• Multiverse Understanding of Cosmological Coincidences
• Physical conditions in the neutral interstellar medium at z=2.43 toward Q2348-011
• Searching for chameleon-like scalar fields with the ammonia method. II. Mapping of cold molecular cores in NH3 and HC3N lines
• Manifestations of a spatial variation of fundamental constants on atomic clocks, Oklo, meteorites, and cosmological phenomena
• Is there further evidence for spatial variation of fundamental constants?
• Constraining a possible time-variation of the gravitational constant through "gravitochemical heating" of neutron stars
• Probing variations in fundamental constants with radio and optical quasar absorption-line observations
• The Wall of Fundamental Constants
• Time drift of cosmological redshifts and its variance
• A new approach for testing variations of fundamental constants over cosmic epochs using FIR fine-structure lines
• Tilted Physics: A Cosmologically Dipole-Modulated Sky
• Sensitivity of Nuclear Transition Frequencies to Temporal Variation of the Fine Structure Constant or the Strong Interaction
• HI 21cm Absorption at $z\sim 2.347$ towards PKS B0438-436
• Early Universe Constraints on Time Variation of Fundamental Constants
• Submillimeter water and ammonia absorption by the peculiar z~0.89 interstellar medium in the gravitational lens of the PKS 1830-211 system
• CMB constraints on the fine structure constant
• 21 cm radiation - a new probe of variation in the fine structure constant
• Variability of the proton-to-electron mass ratio on cosmological scales
• Time variation of proton-electron mass ratio and fine structure constant with runaway dilaton
• Varying couplings in the early universe: correlated variations of $\alpha$ and $G$
• Quantum Corrections to the Cosmological Evolution of Conformally Coupled Fields
• Nuclear Astrophysics of Worlds in the String Landscape
• Varying Alpha: New Constraints from Seasonal Variations
• Why anthropic reasoning cannot predict Lambda
• Multiverses and Cosmology: Philosophical Issues
• Eotvos bounds on couplings of fundamental parameters to gravity
• Constraining a possible time variation of the gravitational constant G with terrestrial nuclear laboratory data
• Moduli Fields as Quintessence and the Chameleon
• How changing physical constants and violation of local position invariance may occur?
• Unifying cosmological and recent time variations of fundamental couplings
• Astronomical and laboratory searches for space-time variation of fundamental constants
• Constraints on time variation of fine structure constant from WMAP-3yr data
• Dark Energy and the MSSM
• WMAP 5-year constraints on time variation of $\alpha$ and $m_e$ in a detailed recombination scenario
• VLT/UVES constraints on the carbon isotope ratio 12C/13C at z=1.15 toward the quasar HE 0515-4414
• Stringent bounds to spatial variations of the electron-to-proton mass ratio in the Milky Way
• Constraining the Variation of G by Cosmic Microwave Background Anisotropies
• A Look at the Abandoned Contributions to Cosmology of Dirac, Sciama and Dicke
• Enhanced Sensitivity to the Time Variation of the Fine-Structure Constant and $m_p/m_e$ in Diatomic Molecules: A Closer Examination of Silicon Monobromide
• Mid- and far-infrared fine-structure line sensitivities to hypothetical variability of the fine-structure constant
• Constraints on temporal variation of fundamental constants from GRBs
• The Fundamental Constants in Physics
• Black Hole Constraints on Varying Fundamental Constants
• Time Variation of Fine Structure Constant and Proton-Electron Mass Ratio with Quintessence
• Transition frequency shifts with fine-structure constant variation for Yb II
• Phase transition in the fine structure constant
• Limits on temporal variation of quark masses and strong interaction from atomic clock experiments
• Laboratory spectroscopy and the search for space-time variation of the fine structure constant using QSO spectra
• Detecting Seasonal Changes in the Fundamental Constants
• Reply to Flambaum and Porsev comment on "21 cm radiation - a new probe of variation in the fine structure constant"
• On spatial variations of the electron-to-proton mass ratio in the Milky Way
• The Future Evolution of White Dwarf Stars Through Baryon Decay and Time Varying Gravitational Constant
• On a natural definition of the kilogram and the ampere: the objectives and consequences
• Retroduction, Multiverse Hypotheses and Their Testability
• Cosmological observations to shed light on possible variations - expectations, limitations and status quo
• Testing a string dilaton model with experimental and observational data
• Varying Constants: Constraints from Seasonal Variations

Cited by in corpus (474)

• Planck 2013 results. XVI. Cosmological parameters
• The Confrontation between General Relativity and Experiment
• Search for New Physics with Atoms and Molecules
• Cosmology and Fundamental Physics with the Euclid Satellite
• Strong constraints on cosmological gravity from GW170817 and GRB 170817A
• Dark Energy
• ESPRESSO@VLT -- On-sky performance and first results
• Teleparallel Gravity: From Theory to Cosmology
• Beyond $\Lambda$CDM: Problems, solutions, and the road ahead
• The $H_0$ Olympics: A fair ranking of proposed models
• Maximal freedom at minimum cost: linear large-scale structure in general modifications of gravity
• Fundamental Physics with the Square Kilometre Array
• Improved limit on a temporal variation of $m_p/m_e$ from comparisons of Yb${}^{+}$ and Cs atomic clocks
• Cosmological constant and vacuum energy: old and new ideas
• Highly charged ions: optical clocks and applications in fundamental physics
• The CosmoVerse White Paper: Addressing observational tensions in cosmology with systematics and fundamental physics
• Progress in Atomic Fountains at LNE-SYRTE
• Searching for an oscillating massive scalar field as a dark matter candidate using atomic hyperfine frequency comparisons
• A Unified Description of Screened Modified Gravity
• MICROSCOPE mission: first constraints on the violation of the weak equivalence principle by a light scalar dilaton
• A gravitational redshift test using eccentric Galileo satellites
• Effective Field Theory of Dark Energy: a Review
• General Relativity and Cosmology: Unsolved Questions and Future Directions
• Violation of the equivalence principle from light scalar dark matter
• Vainshtein screening in a cosmological background in the most general second-order scalar-tensor theory
• Update on Coupled Dark Energy and the $H_0$ tension
• Molecules at z=0.89: A 4-mm-rest-frame absorption line survey toward PKS 1830-211
• The status of varying constants: a review of the physics, searches and implications
• Dynamical vacuum energy in the expanding Universe confronted with observations: a dedicated study
• Observation of the radiative decay of the ${}^{229}\mathrm{Th}$ nuclear clock isomer
• Enhanced effects of variation of the fundamental constants in laser interferometers and application to dark matter detection
• Updated fundamental constant constraints from Planck 2018 data and possible relations to the Hubble tension
• A rapid transition of $G_{\mathrm{eff}}$ at $z_t\simeq 0.01$ as a solution of the Hubble and growth tensions
• Exploring Cosmic Origins with CORE: Cosmological Parameters
• Improved tests of Local Position Invariance using 87Rb and 133Cs fountains
• Roadmap towards the redefinition of the second
• Probing Physics Beyond the Standard Model: Limits from BBN and the CMB Independently and Combined
• Brans-Dicke gravity with a cosmological constant smoothes out $\Lambda$CDM tensions
• New limits on variation of the fine-structure constant using atomic dysprosium
• Tests of Gravitational Symmetries with Pulsar Binary J1713+0747
• What can Cosmology tell us about Gravity? Constraining Horndeski with Sigma and Mu
• Parameterized Post-Einsteinian Gravitational Waveforms in Various Modified Theories of Gravity
• The UVES Large Program for Testing Fundamental Physics II: Constraints on a Change in μ Towards Quasar HE 0027-1836
• Emergent scale symmetry: Connecting inflation and dark energy
• Standard sirens with a running Planck mass
• A new tension in the cosmological model from primordial deuterium?
• Improved BBN Constraints on the Variation of the Gravitational Constant
• Primordial nucleosynthesis
• Impact of instrumental systematic errors on fine-structure constant measurements with quasar spectra
• Do we have any hope of detecting scattering between dark energy and baryons through cosmology?
• A search for varying fundamental constants using Hz-level frequency measurements of cold CH molecules
• New constraints on time-dependent variations of fundamental constants using Planck data
• JWST early Universe observations and ΛCDM cosmology
• Cosmic acceleration in dust only Universe via energy-momentum powered gravity
• Two clock transitions in neutral Yb for the highest sensitivity to variations of the fine-structure constant
• Laser cooled molecules
• Varying the light quark mass: impact on the nuclear force and Big Bang nucleosynthesis
• Gravitational and Chiral Anomalies in the Running Vacuum Universe and Matter-Antimatter Asymmetry
• Point-to-Point Stabilised Optical Frequency Transfer with Active Optics
• Cosmological constraints on post-Newtonian parameters in effectively massless scalar-tensor theories of gravity
• Comparing a mercury optical lattice clock with microwave and optical frequency standards
• Brans-Dicke cosmology with a $\Lambda$- term: a possible solution to $\Lambda$CDM tensions
• Free-space transfer of comb-rooted optical frequencies over an 18 km open-air link
• High-precision limit on variation in the fine-structure constant from a single quasar absorption system
• The UVES Large Program for testing fundamental physics - III. Constraints on the fine-structure constant from 3 telescopes
• Auto-Balanced Ramsey Spectroscopy
• Breaking of the equivalence principle in the electromagnetic sector and its cosmological signatures
• The $H_0$ tension: $\Delta G_N$ vs. $\Delta N_{\mathrm{eff}}$
• Constraining the time variation of Newton's constant $G$ with gravitational-wave standard sirens and supernovae
• K-mouflage Cosmology: the Background Evolution
• Observational Constraints on $f(T)$ gravity from varying fundamental constants
• Running vacuum in the Universe: phenomenological status in light of the latest observations, and its impact on the ${\sigma }_8$ and $H_0$ tensions
• Measurement of the $T_{\mathrm{CMB}}$ evolution from the Sunyaev-Zel'dovich effect
• Screening $\Lambda$ in a new modified gravity model
• Large-scale structure phenomenology of viable Horndeski theories
• Microwave Background Temperature at a Redshift of 6.34 from H2O Absorption
• The ALMA Phasing System: A Beamforming Capability for Ultra-High-Resolution Science at (Sub)Millimeter Wavelengths
• Test of the gravitational redshift with stable clocks in eccentric orbits: application to Galileo satellites 5 and 6
• Measuring the stability of fundamental constants with a network of clocks
• Coupled and uncoupled early dark energy, massive neutrinos and the cosmological tensions
• An ALMA Early Science survey of molecular absorption lines toward PKS1830-211 -- Analysis of the absorption profiles
• Precision measurement of atomic isotope shifts using a two-isotope entangled state
• Constraining fundamental constant evolution with HI and OH lines
• SPT-3G D1: CMB temperature and polarization power spectra and cosmology from 2019 and 2020 observations of the SPT-3G Main field
• Representation-free description of light-pulse atom interferometry including non-inertial effects
• A Generalized Theory of Varying Alpha
• Matter Non-conservation in the Universe and Dynamical Dark Energy
• Probing modified gravity theories and cosmology using gravitational-waves and associated electromagnetic counterparts
• Cosmological implications of scale-independent energy-momentum squared gravity: Pseudo nonminimal interactions in dark matter and relativistic relics
• Constraining $f(T)$ Theories with the Varying Gravitational Constant
• Search for oscillations of fundamental constants using molecular spectroscopy
• Can scale-dependent cosmology alleviate the $H_0$ tension?
• Constraints on changes in the proton-electron mass ratio using methanol lines
• Constraints on the time variation of the gravitational constant using gravitational-wave observations of binary neutron stars
• The Effect of Cosmological Evolution on Solar System Constraints and on the Scalarization of Neutron Stars in Massless Scalar-Tensor Theories
• Search for a drifting proton--electron mass ratio from H${}_2$
• Search for a Variation of the Fine Structure around the Supermassive Black Hole in Our Galactic Center
• Cosmological constant vis-a-vis dynamical vacuum: bold challenging the $\Lambda$CDM
• Generalized framework for testing gravity with gravitational-wave propagation. III. Future prospect
• Effective gravitational coupling in modified teleparallel theories
• Equation of state of the running vacuum
• General Dynamics of Varying-Alpha Universes
• Molecular hydrogen in the z = 2.66 damped Lyman-alpha absorber toward Q J0643-5041
• Late-time cosmology of scalar-tensor theories with universal multiplicative coupling between the scalar field and the matter Lagrangian
• Null Signal for the Cosmic Anisotropy in the Pantheon Supernovae Data
• Running vacuum in the Universe and the time variation of the fundamental constants of Nature
• The Degree of Fine-Tuning in our Universe -- and Others
• Can all cosmological observations be accurately interpreted with a unique geometry?
• General relativity as an attractor for scalar-torsion cosmology
• Manifestations of a spatial variation of fundamental constants on atomic clocks, Oklo, meteorites, and cosmological phenomena
• The variation of fundamental constants and the role of A=5 and A=8 nuclei on primordial nucleosynthesis
• How fundamental are fundamental constants?
• Primordial nucleosynthesis with varying fundamental constants: Improved constraints and a possible solution to the Lithium problem
• Tests of gravitational symmetries with radio pulsars
• The dS swampland conjecture with the electroweak symmetry and QCD chiral symmetry breaking
• The unit of time: present and future directions
• Testing Gravity with Gravitational Waves from Binary Black Hole Mergers: Contributions from Amplitude Corrections
• Broadband near-infrared astronomical spectrometer calibration and on-sky validation with an electro-optic laser frequency comb
• Analysis of Molecular Hydrogen Absorption toward QSO B0642-5038 for a Varying Proton-to-Electron Mass Ratio
• Relic Neutrino Freeze-out: Dependence on Natural Constants
• Microwave and submillimeter molecular transitions and their dependence on fundamental constants
• Fundamental physics with Espresso: Towards an accurate wavelength calibration for a precision test of the fine-structure constant
• Optimising growth of structure constraints on modified gravity
• Quintessential inflation: A tale of emergent and broken symmetries
• State of the art in the determination of the fine structure constant: test of Quantum Electrodynamics and determination of h/mu
• Probing beyond the laser coherence time in optical clock comparisons
• Testing Gravity on Cosmic Scales: A Case Study of Jordan-Brans-Dicke Theory
• Phenomenology of Large Scale Structure in scalar-tensor theories: joint prior covariance of $w_{\text{DE}}$, $\Sigma$ and $\mu$ in Horndeski
• A new era of fine structure constant measurements at high redshift
• Gravitational redshift test with the future ACES mission
• Exacerbating the cosmological constant problem with interacting dark energy
• Asteroseismic constraints on the cosmic-time variation of the gravitational constant from an ancient main-sequence star
• The minimally extended Varying Speed of Light (meVSL)
• Testing Theories of Gravity with Planetary Ephemerides
• Tilted Physics: A Cosmologically Dipole-Modulated Sky
• The cosmology of minimal varying Lambda theories
• On the stability and causality of scalar-vector theories
• Intrinsic Solar System decoupling of a scalar-tensor theory with a universal coupling between the scalar field and the matter Lagrangian
• Axi-Higgs Cosmology
• Running vacuum in QFT in FLRW spacetime: The dynamics of ${\rho }_{\mathrm{vac}}(H)$ from the quantized matter fields
• Regularizing cosmological singularities by varying physical constants
• Solar System Constraints on Scalar-Tensor Gravity with Positive Coupling Constant upon Cosmological Evolution of the Scalar Field
• Measuring the speed of light with Baryon Acoustic Oscillations
• Cosmology Intertwined: A Review of the Particle Physics, Astrophysics, and Cosmology Associated with the Cosmological Tensions and Anomalies
• Clusters of galaxies and variation of the fine structure constant
• Brans-Dicke theory and the emergence of ΛCDM model
• Accurate prediction of clock transitions in a highly charged ion with complex electronic structure
• Varying fundamental constants principal component analysis: additional hints about the Hubble tension
• Machine Learning improved fits of the sound horizon at the baryon drag epoch
• Redshift drift in varying speed of light cosmology
• Variation of fundamental parameters and dark energy. A principal component approach
• First cosmological constraints on the proton-to-electron mass ratio from observations of rotational transitions of methanol
• From configuration to dynamics -- Emergence of Lorentz signature in classical field theory
• Probing scalar dark matter oscillations with neutrino oscillations
• Systematic study and uncertainty evaluation of $P,T$-odd molecular enhancement factors in BaF
• Boosting Ultraviolet Freeze-in in NO Models
• Yoga Dark Energy: Natural Relaxation and Other Dark Implications of a Supersymmetric Gravity Sector
• Prospects of testing late-time cosmology with weak lensing of gravitational waves and galaxy surveys
• Cosmology with relativistically varying physical constants
• Resonator with ultra-high length stability as a probe for Equivalence-Principle-violating physics
• White dwarfs as Physics laboratories: lights and shadows
• Weak-lensing by the large scale structure in a spatially anisotropic universe: theory and predictions
• Constraint on a cosmological variation in the proton-to-electron mass ratio from electronic CO absorption
• Stability of fundamental couplings: a global analysis
• Machine Learning meets the redshift evolution of the CMB Temperature
• Gyromagnetic Factors and Atomic Clock Constraints on the Variation of Fundamental Constants
• Limits on a Gravitational Field Dependence of the Proton--Electron Mass Ratio from H${}_2$ in White Dwarf Stars
• Testing the violation of the equivalence principle in the electromagnetic sector and its consequences in $f(T)$ gravity
• A Closer Earth and the Faint Young Sun Paradox: Modification of the Laws of Gravitation, or Sun/Earth Mass Losses?
• Testing the Cosmic Anisotropy with Supernovae Data: Hemisphere Comparison and Dipole Fitting
• Quantum Harmonic Analysis of the Density Matrix
• Actinide ions for testing the spatial $\alpha -$variation hypothesis
• Using the cosmological recombination radiation to probe early dark energy and fundamental constant variations
• Noether identities in gravity theories with nondynamical backgrounds and explicit spacetime symmetry breaking
• Fundamental cosmology in the E-ELT era: The status and future role of tests of fundamental coupling stability
• BBN constraints on universally-coupled ultralight scalar dark matter
• Inflation from fermions with curvature-dependent mass
• Variations in the Fundamental constants in the QSO Host J1148+5251 at z = 6.4 and the BR1202-0725 System at z = 4.7
• Mimicking dark matter in Horndeski gravity
• Producing the Deuteron in Stars: Anthropic Limits on Fundamental Constants
• Effect of evolutionary physical constants on type-1a supernova luminosity
• Consistency tests of the stability of fundamental couplings and unification scenarios
• Axion Homeopathy: Screening Dilaton Interactions
• A new analysis of fine-structure constant measurements and modelling errors from quasar absorption lines
• The variation of the fine-structure constant from disformal couplings
• Estimates of the change rate of solar mass and gravitational constant based on the dynamics of the Solar System
• Diagnostic of Horndeski Theories
• The Multiverse and Particle Physics
• Limits on the spatial variations of the electron-to-proton mass ratio in the Galactic plane
• Cosmological constant problem: deflation during inflation
• Constraint on the time variation of the fine-structure constant with the SDSS-III/BOSS DR12 quasar sample
• K-mouflage gravity models that pass Solar System and cosmological constraints
• Anisotropic massive Brans-Dicke gravity extension of the standard $\Lambda$CDM model
• Stringent constraints on fundamental constant evolution using conjugate 18 cm satellite OH lines
• Material Size Dependence on Fundamental Constants
• Measuring the fine structure constant on a white dwarf surface; a detailed analysis of Fe V absorption in G191-B2B
• Mirror matter can alleviate the cosmological lithium problem
• Probing unification scenarios with atomic clocks
• Cosmological Constant, Fine Structure Constant and Beyond
• Cosmological Evolution and Solar System Consistency of Massive Scalar-Tensor Gravity
• Editorial note to "Large number coincidences and the anthropic principle in cosmology"
• Merging matter and geometry in the same Lagrangian
• Constraining the scalar-tensor gravity theories with and without screening mechanisms by combined observations
• A study of submillimeter methanol absorption toward PKS1830-211: Excitation, invariance of the proton-electron mass ratio, and systematics
• Variation in the fine-structure constant, distance-duality relation and the next generation of high-resolution spectrograph
• Probing dark energy beyond $z=2$ with CODEX
• Testing the variability of the proton-to-electron mass ratio from observations of methanol in the dark cloud core L1498
• Updated constraints on spatial variations of the fine-structure constant
• Fine-structure constant constraints on dark energy
• Friedmann cosmology with decaying vacuum density in Brans-Dicke theory
• Searching for a Fifth Force with Atomic and Nuclear Clocks
• A gravitational constant transition within cepheids as supernovae calibrators can solve the Hubble tension
• Galaxy clusters and a possible variation of the fine structure constant
• Varying electric charge in multiscale spacetimes
• Heavy photophilic scalar at the LHC from a varying electromagnetic coupling
• Constraints on a possible variation of the fine structure constant from galaxy cluster data
• Ultralight Dark Matter Search with Space-Time Separated Atomic Clocks and Cavities
• Cosmological Evolution of Fundamental Constants: From Theory to Experiment
• Inconstant Planck's constant
• Gravity Theories with Background Fields and Spacetime Symmetry Breaking
• Vacuum Energy Density Measured from Cosmological Data
• Spacetime Symmetry Breaking and Einstein-Maxwell Theory
• Discovery of OH absorption from a galaxy at z~0.05: implications for large surveys with SKA pathfinders
• Effect of transitions in the Planck mass during inflation on primordial power spectra
• Dynamical analysis of the covarying coupling constants in scalar-tensor gravity
• Time-dependent $G$ in Einstein's equations as an alternative to the cosmological constant
• Higgs potential from extended Brans-Dicke theory and the time-evolution of the fundamental constants
• Fine-structure constant constraints on dark energy: II. Extending the parameter space
• From Asymptotic Safety to Dark Energy
• State of the art in the determination of the fine structure constant and the ratio $h/m_{\mathrm{u}}$
• Cosmic Anisotropy and Fast Radio Bursts
• Big-bang nucleosynthesis and cosmic microwave background constraints on non-minimally coupled theories of gravity
• Varying constants quantum cosmology
• Dimensionless physics
• Observational Constraints on Varying-alpha Domain Walls
• Galaxy clusters, type Ia supernovae and the fine structure constant
• Cosmological constant as a fundamental constant
• Variation of $\alpha$ from a Dark Matter Force
• Effective field equations and scale-dependent couplings in gravity
• Reconstruction of mimetic gravity in a non-singular bouncing universe from quantum gravity
• Scalar-tensor cosmologies with dust matter in the general relativity limit
• The cosmological evolution condition of the Planck constant in the varying speed of light models through adiabatic expansion
• Recent results in nuclear astrophysics
• Probing the constancy of the speed of light with future galaxy survey: the case of SKA and Euclid
• MICROSCOPE's constraint on a short-range fifth force
• Roles of ${}^7$Be$(n,p{)}^7$Li resonances in big bang nucleosynthesis with time-dependent quark mass and Li reduction by a heavy quark mass
• $\mathbf{O}(D,D)$ completion of the Friedmann equations
• Testing maser-based evolutionary schemes: A new search for 37.7-GHz methanol masers
• Where are the Walls?
• Neutrino masses from large-scale structures: future sensitivity and theory dependence
• Central charge criticality of charged AdS black hole surrounded by different fluids
• Stability of symmetric teleparallel scalar-tensor cosmologies with alternative connections
• Current and Future White Dwarf Mass-radius Constraints on Varying Fundamental Couplings and Unification Scenarios
• Testing a varying-$\Lambda$ model for dark energy within Co-varying Physical Couplings framework
• Varying Coupling Constants and Their Interdependence
• Searching for dark matter with the Th-229 nuclear lineshape from laser spectroscopy
• Probing variation of the fine-structure constant in runaway dilaton models using Strong Gravitational Lensing and Type Ia Supernovae
• On dilatons with intrinsic decouplings
• Which Fundamental Constants for CMB and BAO?
• A statefinder luminosity distance formula in varying speed of light cosmology
• Effective cosmological constant induced by stochastic fluctuations of Newton's constant
• Enhanced effects of temporal variation of the fundamental constants in ^{2}Π_{1/2} term diatomic molecules: ^{207}Pb^{19}F
• Search for varying constants of nature from astronomical observation of molecules
• Testing the weak equivalence principle by differential measurements of fundamental constants in the Magellanic Clouds
• Variations in fundamental constants at the cosmic dawn
• Dark energy constraints from ESPRESSO tests of the stability of fundamental couplings
• Dark energy and Equivalence Principle constraints from astrophysical tests of the stability of the fine-structure constant
• Constraint on a varying proton-to-electron mass ratio from H2 and HD absorption at z = 2.34
• Fundamental Constant Observational Bounds on the Variability of the QCD Scale
• Late Time Acceleration of the 3-Space in a Higher Dimensional Steady State Universe in Dilaton Gravity
• Recovering a redshift-extended VSL signal from galaxy surveys
• Can a variable gravitational constant resolve the Faint Young Sun Paradox ?
• Constraining possible variations of the fine structure constant in strong gravitational fields with the K$\alpha$ iron line
• Thomson scattering: One rate to rule them all
• Varying physical constants and the lithium problem
• Current and future constraints on extended Bekenstein-type models for a varying fine-structure constant
• Oklo reactors and implications for nuclear science
• Consistency of local and astrophysical tests of the stability of fundamental constants
• Fifth force induced by a chameleon field on nested cylinders
• Ab initio relativistic treatment of the intercombination $a^3\Pi -X^1{\Sigma }^{+}$ Cameron system of the CO molecule
• Growth of non-linear structures and spherical collapse in the Galileon Ghost Condensate model
• Generalized Brans-Dicke theories in light of evolving dark energy
• Extending applicability of bimetric theory: chameleon bigravity
• Reappraisal of the limit on the variation in $\alpha$ implied by Oklo
• Transitions in Zr, Hf, Ta, W, Re, Hg, Ac and U ions with high sensitivity to variation of the fine-structure constant
• Does the Newton's gravitational constant vary sinusoidally with time? Orbital motions say no
• Constraining the evolution of Newton's constant with slow inspirals observed from spaceborne gravitational-wave detectors
• Gravitational Higgs Mechanism in Neutron Star Interiors
• Constraints on the electron-to-proton mass ratio variation at the epoch of reionization
• Viscosity and diffusion in life processes and tuning of fundamental constants
• Newtonian approximation and possible time-varying $G$ in nonlocal gravities
• Tachyon with an inverse power-law potential in a braneworld cosmology
• A new approach to modifying theories of gravity
• Visible transitions in Ag-like and Cd-like lanthanide ions
• Fundamental Cosmology from Precision Spectroscopy: I. Varying Couplings
• A stellar test of the physics of unification
• Further consistency tests of the stability of fundamental couplings
• Quantum Haplodynamics, Dark Matter and Dark Energy
• Probing the time variation of fine structure constant using galaxy clusters and quintessence model
• Discovery of CO absorption at z=0.05 in G0248+430
• Constraining a possible time-variation of the speed of light along with the fine-structure constant using strong gravitational lensing and Type Ia supernovae observations
• Particle creation and decay in nonminimally coupled models of gravity
• Cosmic Variation of Proton to Electron Mass Ratio with an interacting Higgs Scalar Field
• Generalized Entropy Implies Varying-G: Horizon Area Dependent Field Equations and Black Hole-Cosmology Coupling
• Primordial nucleosynthesis with varying fundamental constants: Degeneracies with cosmological parameters
• One-loop effective scalar-tensor gravity
• Dimensionless cosmology
• Current and future constraints on Bekenstein-type models for varying couplings
• Varying constants entropic--$\Lambda$CDM cosmology
• Fine-structure constant constraints on Bekenstein-type models
• Photoassociation of ultracold molecules near a Feshbach resonance as a probe of the electron-proton mass ratio variation
• Prospects of nuclear-coupled-dark-matter detection via correlation spectroscopy of I${}_2^{+}$ and Ca${}^{+}$
• Constraints on the Variation of Physical Constants, Equivalence Principle Violation, and a Fifth Force from Atomic Experiments
• The Geometrical Origin of Dark Energy
• Is Cosmological Tuning Fine or Coarse?
• On the wall velocity dependence of electroweak baryogenesis
• Fundamental Physics with ESPRESSO, Constraining a simple parametrisation for varying $\alpha$
• Interpretation of geodesy experiments in non-Newtonian theories of gravity
• Consequences of Fine-Tuning for Fifth Force Searches
• Diatomic rovibronic transitions as potential probes for proton-to-electron mass ratio across cosmological time
• Variations of the fine-structure constant $\alpha$ in exotic singularity models
• Varying-Alpha and K-Essence
• Cyclic multiverses
• Test of the Equivalence Principle in the Dark Sector on Galactic Scales
• Variation of the fine structure constant in the light of recent helium abundance measurement
• Hubble tension as a window on the gravitation of the dark matter sector: Exploration of a family of models
• Bounds on the Horndeski Gauge-Gravity Coupling
• Probing Galactic variations in the fine-structure constant using solar twin stars: systematic errors
• Constraining massless dilaton theory at Solar system scales with the planetary ephemeris INPOP
• Cosmological and astrophysical constraints on tachyon dark energy models
• A test of unification towards the radio source PKS1413+135
• Extended Chameleons
• Laser spectroscopy of cold molecules
• [CI], [CII] and CO emission lines as a probe for alpha variations at low and high redshifts
• Constraints on extended Bekenstein models from cosmological, astrophysical, and local data
• Modelling spatial variations of the speed of light
• Observational Constraints on Varying Alpha in $\Lambda (\alpha )$CDM Cosmology
• Probing the electron-to-proton mass ratio gradient in the Milky Way with class I methanol masers
• Observational constraints on spatial anisotropy of G from orbital motions
• Probe the gravitational constant variation via the propagation of gravitational waves
• Redshifting of cosmological black bodies in BSBM varying-alpha theories
• Prospects of Probing Dark Matter Condensates with Gravitational Waves
• A search for the fine-structure constant evolution from fast radio bursts and type Ia supernovae data
• Varying alpha, blinding, and bias in existing measurements
• Testing the Equivalence Principle with Strong Lensing Time Delay Variations
• Violation of the equivalence principle induced by oscillating rest mass and transition frequency, and its detection in atom interferometers
• Effects of a scalar fifth force on the dynamics of a charged particle as a new experimental design to test chameleon theories
• Astrophysical constraints on the proton-to-electron mass ratio with FAST
• Proposal for an optical interferometric measurement of the gravitational red-shift with satellite systems
• Orbital effects of spatial variations of fundamental coupling constants
• Fundamental physics with ESPRESSO: Constraints on Bekenstein and dark energy models from astrophysical and local probes
• Black branes in four-dimensional conformal equivalent theories
• Solving nonlinear Klein-Gordon equations on unbounded domains via the Finite Element Method
• Mirror Dark Sector Solution of the Hubble Tension with Time-varying Fine-structure Constant
• The effect of the gravitational constant variation on the propagation of gravitational waves
• Higgs effective potential in a perturbed Robertson-Walker background
• Constraining Coupling Constants' Variation with Supernovae, Quasars, and GRBs
• A four-dimensional ΛCDM-type cosmological model induced from higher dimensions using a kinematical constraint
• Detecting Ultralight Dark Matter with Matter Effect
• Fundamental Cosmology from Precision Spectroscopy: II. Synergies with supernovae
• Scalar Dark Energy Models and Scalar-Tensor Gravity: Theoretical Explanations for the Accelerated Expansion of Present Universe
• Asymptotic bound on slow-roll parameter in stringy quintessence model
• Methanol absorption in PKS B1830-211 at milliarcsecond scales
• Incompatibility of fine-structure constant variations at recombination with local observations
• Examining the validity of the minimal varying speed of light model through cosmological observations: relaxing the null curvature constraint
• Fundamental physical constants: current results in search for variations and their description
• Cosmological Model with Cosmic transit behaviour in Brans-Dicke Theory
• Cosmological attractors to general relativity and spontaneous scalarization with disformal coupling
• Distinguishing freezing and thawing dark energy models through measurements of the fine-structure constant
• Observational Constraints on Early Coupled Quintessence
• Compact objects with scalar charge embedded in a magnetic or electric field in Einstein-Maxwell-dilaton theories
• Resilience and implications of adiabatic CMB cooling
• Cosmological Ohm's law and dynamics of non-minimal electromagnetism
• Non-parametric reconstruction of the fine structure constant with galaxy clusters
• Measuring the speed of light with cosmological observations: current constraints and forecasts
• Fisher matrix forecasts for astrophysical tests of the stability of the fine-structure constant
• Coupling quintessence kinetics to electromagnetism
• Gravitational lens time-delay as a probe of a possible time variation of the fine-structure constant
• Growth of Linear Perturbations in a Universe with Superfluid Dark Matter
• Cosmological constraints on $\Lambda (\alpha )$CDM models with time-varying fine structure constant
• A Large Mass Hierarchy from a Small Non-minimal Coupling
• Space-time variation of the s and c quark masses
• Second law of thermodynamics in nonminimally coupled gravity
• Spatial and temporal variations of the fine-structure constant in the Finslerian universe
• Varying constants driven baryogenesis
• Spatial variation of fundamental constants: testing models with thermonuclear supernovae
• Ultra-local models of modified gravity without kinetic term
• $\Lambda$CDM cosmology with a quiescent anisotropy in a higher dimensional steady state universe
• Varying gauge couplings and collider phenomenology
• Constraining an Expanding Locally Anisotropic metric from the Pioneer anomaly
• Relativistic frequency shifts in Cr, Ti, Fe, Ni, Ca, Na, and V to search for variation in the fine structure constant
• On the Stability of Fundamental Couplings in the Galaxy
• New Anisotropic Sudden Singularities and Dimensional Reduction
• Is Quintessence an Indication of a Time-Varying Gravitational Constant?
• Probing Galactic variations in the fine-structure constant using solar twin stars: methodology and results
• Unveiling Time-Varying Signals of Ultralight Bosonic Dark Matter at Collider and Beam Dump Experiments
• Energy production in varying α theories
• Computational insight into diatomic molecules as probes to measure the variation of the proton-to-electron mass ratio
• Challenges to a sharp change in $G$ as a solution to the Hubble tension
• Relativistic atomic structure calculations in support of spectroscopy
• Non-minimal coupling inspires the Dirac cosmological model
• Accelerated expansion of the Universe a la the Stueckelberg mechanism
• Sensitivity of Tunneling-Rotational Transitions in Ethylene Glycol to Variation of Electron-to-Proton Mass Ratio
• Constraining spatial variations of the fine-structure constant in symmetron models
• Big Bang Nucleosynthesis with Stable ${}^8$Be and the Primordial Lithium Problem
• Estimations of the cosmological parameters from the observational variation of the fine structure constant
• Magnetic contributions in Bekenstein type models
• Singularity theorems for warped products and the stability of spatial extra dimensions
• General solution of a cosmological model induced from higher dimensions using a kinematical constraint
• The Mystery of Alpha and the Isotopes
• Testing the variation of the fine structure constant with strongly lensed gravitational waves
• Extrinsic and intrinsic effects setting viscosity in complex fluids and life processes: the role of fundamental physical constants
• Measuring the Time Variation of the Fine-structure Constant with Quasars Detected by LAMOST
• Dilaton-induced variations in Planck constant and speed of light: An alternative to Dark Energy
• An investigation of a varying G through Strong Lensing and SNe Ia observations
• Implications of the Oklo phenomenon in a chiral approach to nuclear matter
• Effect of temperature on measurement of fundamental constants using white dwarfs in Gaia-EDR3 survey
• Cosmology from a running vacuum model driven by a scalar field
• Cosmological evolution of the proton-to-electron mass ratio in an extended Brans-Dicke theory
• QSNET, a network of clocks for measuring the stability of fundamental constants
• Cosmological constant, information and gedanken experiments with black hole horizons
• Anthropic Selection of Physical Constants, Quantum Entanglement, and the Multiverse Falsifiability
• Effects of Variable Newton Constant During Inflation
• Assessing the viability of successful reconstruction of the dynamics of dark energy using varying fundamental couplings
• Fundamental physics tests using the propagation of GNSS signals
• Robust laboratory limits on a cosmological spatial gradient in the electromagnetic fine-structure constant from accelerometer experiments
• Evolution of Size, Mass, and Density of Galaxies Since Cosmic Dawn
• The dynamics of vacuum, gravity and matter: Implications on the fundamental constants
• Impact of inhomogeneities on slowly rolling Quintessence: implications for the local variations of the fine-structure constant
• Search for Variations of Fundamental Constants
• Planetary motion on an expanding locally anisotropic background
• Fundamental physical constants, operation of physical phenomena and entropy increase
• Cosmological Time Evolution of the Higgs Mass and Gravitational Waves
• A mechanism to generate varying speed of light via Higgs-dilaton coupling: Theory and cosmological applications
• A model for time-evolution of coupling constants
• Constraining Co-Varying Coupling Constants from Globular Cluster Age
• Studying the variation of fundamental constants at the Cosmic Ray Extremely Distributed Observatory
• Dilatonic Topological Defects in 3+1 Dimensions and their Embeddings
• Quantum mechanix plus Newtonian gravity violates the universality of free fall
• New analysis of SNeIa Pantheon Catalog: Variable speed of light as an alternative to dark energy
• Mimetic Tensor-Vector-Scalar Cosmology: Incorporating Dark Matter, Dark Energy and Stiff Matter
• Discrete Cosmological Models in the Brans-Dicke Theory of Gravity
• Primordial Nucleosynthesis
• Low redshift constraints on scale-covariant models
• Constraining spacetime variations of nuclear decay rates from light curves of type Ia supernovae
• A plug-and-play solution for characterizing two-way optical frequency transfer over free-space
• Dynamical analysis of Brans-Dicke Universe with inverse power-law effective potential
• New constraints on the values of the fundamental constants at a look-back time of 7.3 Gyr
• Gravitational baryogenesis beyond the spectator approximation
• Does Cosmology require Hermiticity in Quantum Mechanics?
• Brans-Dicke-like field for co-varying $G$ and $c$: observational constraints
• Constraints on the Variation of the QCD Interaction Scale ${\Lambda }_{\text{QCD}}$
• MOND as a transformation between non-inertial reference frames via Sciama's interpretation of Mach's Principle
• On Non-triviality of Units Transformations
• Quarks to Cosmos: Particles and Plasma in Cosmological evolution
• A new mechanism for freezing extra dimensions with higher-order curvature terms
• Review of detector requirements: some challenges for the present
• Avoiding unrealistic priors: the case of dark energy constraints from the time variation of the fine-structure constant
• Revisiting the Constancy of the Speed of Light: Galaxy Cluster Mass Bias Implications
• Investigating a Possible Variation of the Gravitational Constant Through Gas Mass Fraction Measurements and Type Ia Supernovae Observations
• Constraining runaway dilaton models using joint gravitational-wave and electromagnetic observations
• On Generalized Theories of Varying Fine Structure Constant
• A New Approach to Flatness, Horizon and Late-time Accelerating Expansion Problems on the basis of Mach Principle
• A model-independent test of speed of light variability with cosmological observations
• A speed limit on tachyon fields from cosmological and fine-structure data
• Unitarily Inequivalent Vacua and Long-Range Forces: Phenomenology with Scalar Boson Mass-Shift
• Sign Switching Dark Energy from a Running Barrow Entropy
• Solar System and Atomic Clock Bounds on Locally Coupled Swampland Scalars
• Geometric Matching of Local Static Regions in Cosmological Spacetimes with an Evolving Lapse
• Cosmological Consequences of Varying Couplings in Gravity Action
• Do alien particles exist, and can they be detected?
• Dark Energy and the Time Dependence of Fundamental Particle Constants
• Future Dark Energy Constraints from Atomic Clocks
• Quantum Physics in Space