Time variation of fundamental constants in nonstandard cosmological models

Mosquera, M. E.; Civitarese, O.

doi:10.1103/physrevc.96.045802

Cited by 13 publications

(9 citation statements)

References 73 publications

(99 reference statements)

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“…As one may check (see Figs. 5 and 6 of [15]), such limit is weakened by opening up the parameter space to variations of the number of relativistic species or the helium abundance (see also [37] for a investigation of the lithium abundance problem in BBN scenarios with a varying α). Moreover, the value of the Hubble constant shifts to H 0 = 65.1 ± 1.8 km/s/Mpc if α is allowed to vary, which exacerbates the tension with the value of the Hubble constant measured recently, H 0 = 73.45 ± 1.66 km/s/Mpc, using cepheids and low-z type Ia supernovae [45].…”

Section: Introductionmentioning

confidence: 99%

Galaxy clusters and a possible variation of the fine structure constant

Colaço

Holanda

Silva

et al. 2019

J. Cosmol. Astropart. Phys.

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Galaxy clusters have been used as a cosmic laboratory to verify a possible time variation of fundamental constants. Particularly, it has been shown that the ratio YSZD 2 A /CXZSYX, which is expected to be constant with redshift, can be used to probe a variation of the fine structure constant, α. In this ratio, YSZD 2 A is the integrated comptonization parameter of a galaxy cluster obtained via Sunyaev-Zel'dovich (SZ) effect observations multiplied by its angular diameter distance, DA, YX is the X-ray counterpart and CXSZ is an arbitrary constant. Using a combination of SZ and X-ray data, a recent analysis found YSZD 2 A /CXZSYX = Cα(z) 3.5 , where C is a constant. In this paper, following previous results that suggest that a variation of α necessarily leads to a violation of the cosmic distance duality relation, DL/DA(1 + z) 2 = 1, where DL is the luminosity distance of a given source, we derive a new expression, YSZD 2 A /CXSZYX = Cα 3.5 η −1 (z), where η(z) = DL/DA(1 + z) 2 . In particular, considering the direct relation η(z) ∝ α(z) 1/2 , derived from a class of dilaton runaway models, and 61 measurements of the ratio YSZD 2 A /CXSZYX provided by the Planck collaboration, we discuss bounds on a possible variation of α. We also estimate the value of the constant C, which is compatible with the unity at 2σ level, indicating that the assumption of isothermality for the temperature profile of the galaxy clusters used in the analysis holds. 95.36.+x, 98.80.Es

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Section: Introductionmentioning

confidence: 99%

Galaxy clusters and a possible variation of the fine structure constant

Colaço

Holanda

Silva

et al. 2019

J. Cosmol. Astropart. Phys.

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“…It should be stressed that unlike other methods described in this paper, it is necessary to asume a theoretical model for the strong interaction within this analysis. Mosquera & Civitarese (2017) considered the Argonne potential for the nucleon-nucleon interaction. From the comparison with the observed abundances of D, 4 He and 7 Li they obtained:…”

Section: Big Bang Nucleosynthesis (Bbn)mentioning

confidence: 99%

Variation of fundamental constants and white dwarfs

Landau

2019

Proc. IAU

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Theories that attempt to unify the four fundamental interactions and alternative theories of gravity predict time and/or spatial variation of the fundamental constants of nature. Different versions of these theories predict different behaviours for these variations. As a consequence, experimental and observational bounds are an important tool to check the validity of such proposals. In this paper, we review constraints on the possible variation of the fundamental constants from astronomical observations and geophysical experiments designed to test the constancy of the fundamental constants of nature over different timescales. We also focus on the limits that can be obtained from white dwarfs, which can constrain the variation of the constants with the gravitational potential.

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“…As a consequence, modern physics theories indicate that in the gauge couplings with a common three-dimensional subspace, the fine-structure constant α, the proton-to-electron mass ratio µ, and the gravitational constant would differ to the opposite square of the mean scale of the extra-dimensions. The evolution of these dimensions' scale size is linked with their space or time variations [11][12][13][14]. Furthermore, this has been recently confirmed by the change of α over cosmological space-time.…”

Section: Introductionmentioning

confidence: 96%

Constraints on the spatial and temporal variations of the gravitational constant from quasar spectra

2021

Preprint

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The possible variations of fundamental physical constants present a critical examination of grand unification theories (GUTs). The most useful way to investigate these variations could be based on observations that directly test them with a deep-look back in time in the universe. Using combinations of high-resolution spectra of quasars and Ritz wavelengths in the laboratory, we found an upper limit on a possible cosmological deviation of the gravitational ̇ ⁄ = (0.918 ± 2.830) × 10 yr over cosmic timescales.. This result may be considered as a new tool for checking the physical phenomena of the GUTs.

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Time variation of fundamental constants in nonstandard cosmological models

Cited by 13 publications

References 73 publications

Galaxy clusters and a possible variation of the fine structure constant

Galaxy clusters and a possible variation of the fine structure constant

Variation of fundamental constants and white dwarfs

Constraints on the spatial and temporal variations of the gravitational constant from quasar spectra

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