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Related papers: The Fine Structure Constant and Habitable Planets

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The effect of fractal space time of the quantum particles on the variation of the fine structure constant $\alpha$ has been studied. The variation of fine structure constant has been investigated around De Broglie length $\lambda$ and…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-05 A. Bhattacharya , A. Chandra , B. Chakrabarti

We reconsider several current bounds on the variation of the fine-structure constant in models where all gauge and Yukawa couplings vary in an interdependent manner, as would be expected in unified theories. In particular, we re-examine the…

High Energy Physics - Phenomenology · Physics 2009-09-15 Keith A. Olive , Maxim Pospelov , Yong-Zhong Qian , Alain Coc , Michel Casse , Elisabeth Vangioni-Flam

I briefly present some current theoretical motivations for time or space variations of the fundamental constants of nature and review current key observational results. I focus on the fine-structure constant, and particularly on…

Astrophysics · Physics 2007-05-23 C. J. A. P. Martins

In some cosmological theories with varying constants there are anthropic reasons why the expansion of the universe must not be too {\it close} to flatness or the cosmological constant too close to zero. Using exact theories which…

Astrophysics · Physics 2009-11-07 J. D. Barrow , H. B. Sandvik , J. Magueijo

The variation of fine structure constant with the variation of velocity of light has been studied considering contribution to the permeability and permittivity of the vacuum and incorporating contribution of fractal potential originated…

General Physics · Physics 2017-06-09 A. Bhattacharya , R. Saha , R. Ghosh

We study the corrections to the fine-structure constant from the generalized uncertainty principle in the spacetime of a domain wall. We also calculate the corrections to the standard formula to the energy of the electron in the hydrogen…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-20 Luigi Tedesco

Determining planetary habitability is a complex matter, as the interplay between a planet's physical and atmospheric properties with stellar insolation has to be studied in a self consistent manner. Standardized atmospheric models for…

Earth and Planetary Astrophysics · Physics 2015-07-15 Siegfried Eggl , Nikolaos Georgakarakos , Elke Pilat-Lohinger

With the discovery of hundreds of exoplanets and a potentially huge number of Earth-like planets waiting to be discovered, the conditions for their habitability have become a focal point in exoplanetary research. The classical picture of…

Earth and Planetary Astrophysics · Physics 2015-06-22 M. Guedel , R. Dvorak , N. Erkaev , J. Kasting , M. Khodachenko , H. Lammer , E. Pilat-Lohinger , H. Rauer , I. Ribas , B. E. Wood

We explore the potential variation of two fundamental constants, the fine-structure constant $\alpha$ and the proton-to-electron mass ratio $\mu$, within the framework of modified gravity theories and finite-temperature effects. Utilising…

Solar and Stellar Astrophysics · Physics 2025-09-17 Akhil Uniyal , Surajit Kalita , Yosuke Mizuno , Sayan Chakrabarti , Yan Lu

We present stellar evolution models for 0.5 - 1.2 \Msol at scaled metallicities of 0.1 - 1.5 Z\sol and O/Fe values of 0.44 - 2.28 O/Fe\sol. The time dependent evolution of habitable zone boundaries are calculated for each stellar evolution…

Solar and Stellar Astrophysics · Physics 2016-12-20 Amanda Truitt , Patrick A. Young , Alexander Spacek , Luke Probst , Jeremy Dietrich

Recent experimental data indicates that the fine structure constant alpha may be varying on cosmological time scales. We consider the possibility that such a variation could be induced by a second order phase transition which occurs at late…

High Energy Physics - Phenomenology · Physics 2010-04-05 Z. Chacko , C. Grojean , M. Perelstein

We present measurements of absorption by the 21cm hyperfine transition of neutral hydrogen toward radio sources at substantial look-back times. These data are used in combination with observations of rotational transitions of common…

We discuss present and future cosmological constraints on variations of the fine structure constant $\alpha$ induced by an early dark energy component having the simplest allowed (linear) coupling to electromagnetism. We find that current…

Cosmology and Nongalactic Astrophysics · Physics 2011-08-08 Erminia Calabrese , Eloisa Menegoni , C. J. A. P. Martins , Alessandro Melchiorri , Graca Rocha

A means to extract the fine-structure constant $\alpha$ from precision spectroscopic data on one-electron ions is presented. We show that in an appropriately weighted difference of the bound-electron $g$ factor and the ground state energy,…

Atomic Physics · Physics 2020-06-26 H. Cakir , N. S. Oreshkina , I. A. Valuev , V. Debierre , V. A. Yerokhin , C. H. Keitel , Z. Harman

We discuss the fundamemtal constants in the Standard Model of particle physics, in particular possible changes of these constants on the cosmological time scale. The Grand Unification of the observed strong, electromagnetic and weak…

High Energy Physics - Phenomenology · Physics 2016-10-25 Harald Fritzsch

A method offering an order of magnitude sensitivity gain is described for using quasar spectra to investigate possible time or space variation in the fine structure constant, alpha. Applying the technique to a sample of 30 absorption…

The Anthropic Principle has been with us since the 1970s. This Principle is advanced to account for the "fine tuning" of the 25 constants of the Standard Model of Particle Physics. Were these constants very different, life could not exist.…

History and Philosophy of Physics · Physics 2022-05-26 Stuart Kauffman

We analyse the constraints obtained from new atomic clock data on the possible time variation of the fine structure `constant' and the electron-proton mass ratio and show how they are strengthened when the seasonal variation of Sun's…

High Energy Physics - Phenomenology · Physics 2008-11-26 John D. Barrow , Douglas J. Shaw

We consider the signatures of a domain wall produced in the spontaneous symmetry breaking involving a dilaton-like scalar field coupled to electromagnetism. Domains on either side of the wall exhibit slight differences in their respective…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-18 Keith A. Olive , Marco Peloso , Jean-Philippe Uzan

We relate the reported variation in the value of the fine structure constant to a possible non-universality of the gravitational interaction with respect to different particle generations.

High Energy Physics - Phenomenology · Physics 2007-05-23 Johann Rafelski