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The effects of phase space deformations in standard scalar field cosmology are studied. The deformation is introduced by modifying the symplectic structure of the minisuperspace variables to have a deformed Poisson algebra among the…

High Energy Physics - Theory · Physics 2013-08-09 S. Pérez-Payán , M. Sabido , C. Yee

We make use of Dirac LNH and results for a time varying fine structure constant in order to derive possible laws of variation for speed of light, the number of nucleons in the Universe, energy density and gravitational constant. By…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Marcelo S. Berman , Luis A. Trevisan

Detection of high-redshift absorption in the optical spectra of quasars have provided a powerful tool to measure spatial and temporal variations of physical ``constants'' in the Universe. It is demonstrated that high sensitivity to the…

Atomic Physics · Physics 2009-10-31 V. A. Dzuba , V. V. Flambaum , J. K. Webb.

Aims. We constrain a hypothetical variation in the fundamental physical constants over the course of cosmic time. Methods. We use unique observations of the CO(7-6) rotational line and the [CI] 3P_2 - 3P_1 fine-structure line towards a…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-12 S. A. Levshakov , F. Combes , F. Boone , I. I. Agafonova , D. Reimers , M. G. Kozlov

We consider a cosmological model with a variable gravitational constant, G, based on a scalar-tensor theory. Using the recent observational data for the Hubble diagram of type Ia supernovae (SNeIa) we find a phenomenological expression…

General Relativity and Quantum Cosmology · Physics 2008-11-26 E. Garcia-Berro , Yu. A. Kubyshin , P. Loren-Aguilar , J. Isern

We study transitions between ground and low-energy excited states of heavy ions corresponding to s-d single-electron transitions or s^2-d^2 double-electron transitions. The large nuclear charge Z and significant change in angular momentum…

Atomic Physics · Physics 2011-12-02 J. C. Berengut , V. A. Dzuba , V. V. Flambaum

This study explores the dynamics and phase-space behavior of a multi-component dark energy model, where the dark sector consists of a minimally coupled canonical scalar field and the cosmological constant, using a dynamical system analysis…

General Relativity and Quantum Cosmology · Physics 2025-05-16 Prasanta Sahoo , Nandan Roy , Himadri Shekhar Mondal

We calculated the dependence of the transition frequencies on the fine-structure constant $\alpha$ ($q$-factors) for Ni~II. Nickel is one of the few elements with high sensitivity to $\alpha$-variation, whose lines are observed at high…

Atomic Physics · Physics 2014-11-03 E. A. Konovalova , M. G. Kozlov , R. T. Imanbaeva

A theory of special inconstancy, in which some fundamental physical constants such as the fine-structure and gravitational constants may vary, is proposed in pregeometry. In the special theory of inconstancy, the \alpha-G relation of…

General Physics · Physics 2015-04-21 Hidezumi Terazawa

We study the $\Lambda(\alpha)$CDM models with $\Lambda(\alpha)$ being a function of the time-varying fine structure constant $\alpha$. We give a close look at the constraints on two specific $\Lambda(\alpha)$CDM models with one and two…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-13 Jin-Jun Zhang , Lu Yin , Chao-Qiang Geng

The interplay between cosmology and strongly coupled dynamics can yield transient spectral features that vanish at late times, but which may leave behind phenomenological signatures in the spectrum of primordial fluctuations. Of particular…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-18 Jay Hubisz , Seung J. Lee , He Li , Bharath Sambasivam

Theories unifying gravity and other interactions suggest the possibility of spatial and temporal variation of physical ``constants'' in the Universe. Detection of high-redshift absorption systems intersecting the sight lines towards distant…

Atomic Physics · Physics 2009-08-18 V. A. Dzuba , V. V. Flambaum , J. K. Webb.

We extend our recent work on the effects of a time-varying fine-structure constant $\alpha$ in the cosmic microwave background, by providing a thorough analysis of the degeneracies between $\alpha$ and the other cosmological parameters, and…

The effects of phase space deformations on Kalutza-Klein cosmology are studied. The deformation is introduced by modifying the symplectic structure of the minisuperspace variables. In the deformed model, we find an accelerating scale factor…

General Relativity and Quantum Cosmology · Physics 2016-03-30 M. Sabido , C. Yee-Romero

The fine-structure constant, $\alpha$, controls the strength of the electromagnetic interaction. There are extensions of the standard model in which $\alpha$ is dynamical on cosmological length and time-scales. The physics of the cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-27 Tristan L. Smith , Daniel Grin , David Robinson , Davy Qi

We investigate the joint effect of the cosmological phase transitions, thermal light dark matter, and the lepton asymmetry on the big bang nucleosynthesis and cosmic microwave background. We find that all of them can modify the predictions…

High Energy Physics - Phenomenology · Physics 2023-10-06 Shihao Deng , Ligong Bian

We studied the role of fundamental constants in an updated recombination scenario, focusing on the time variation of the fine structure constant \alpha and the electron mass m_e in the early Universe. Using CMB data including WMAP 5-yr…

Cosmology and Nongalactic Astrophysics · Physics 2010-03-02 Claudia G. Scóccola , Susana J. Landau , Hector Vucetich

The existing observational data on possible variations of fundamental physical constants (FPC) confirm more or less confidently only a variability of the fine structure constant $\alpha$ in space and time. A model construction method is…

General Relativity and Quantum Cosmology · Physics 2015-06-12 K. A. Bronnikov , V. N. Melnikov , S. G. Rubin , I. V. Svadkovsky

We study ultranarrow $5s_{1/2}$ - $4f_{5/2}$ transitions in Nd$^{13+}$ and Sm$^{15+}$ and demonstrate that they lie in the optical region. The transitions are insensitive to external perturbations. At the same time they are sensitive to the…

Atomic Physics · Physics 2015-06-11 V. A. Dzuba , A. Derevianko , V. V. Flambaum

We show that observational limits on the possible time variation of constants of Nature are significantly affected by allowing for both space and time variation. Bekenstein's generalisation of Maxwell's equations to allow for cosmological…

Astrophysics · Physics 2009-10-31 John D. Barrow , Chris O'Toole
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