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We report preliminary results from a third sample of quasar absorption line spectra from the Keck telescope which has been studied to search for any possible variation of the fine structure constant, alpha. This third sample, which is…

Astrophysics · Physics 2009-08-18 J. K. Webb , M. T. Murphy , V. V. Flambaum , S. J. Curran

In 2003 we have measured the absolute frequency of the $(1S, F=1, m_F=\pm 1) \leftrightarrow (2S, F'=1, m_F'=\pm 1)$ two-photon transition in atomic hydrogen. We observed a variation of $(-29\pm 57)$ Hz over a 44 months interval separating…

Starting from astrophysical indications that the fine structure constant might undergo a small cosmological time shift, we discuss the implications of such an effect from the point of view of particle physics. Grand unification implies…

High Energy Physics - Phenomenology · Physics 2011-09-13 Xavier Calmet , Harald Fritzsch

We propose to use weak measurements away from the weak-value amplification regime to carry out precision measurements of time delays of light. Our scheme is robust to several sources of noise that are shown to only limit the relative…

Quantum Physics · Physics 2013-02-27 Grégory Strübi , C. Bruder

For data sets with similar features, for example highly correlated features, most existing stability measures behave in an undesired way: They consider features that are almost identical but have different identifiers as different features.…

Machine Learning · Statistics 2021-01-18 Andrea Bommert , Jörg Rahnenführer

Standard Model extensions often predict low-mass and very weakly interacting particles, such as the axion. A number of small-scale experiments at the intensity/precision frontier are actively searching for these elusive particles,…

The abundance of functional observations in scientific endeavors has led to a significant development in tools for functional data analysis (FDA). This kind of data comes with several challenges: infinite-dimensionality of function spaces,…

Methodology · Statistics 2015-12-11 J. S. Marron , James O. Ramsay , Laura M. Sangalli , Anuj Srivastava

A quantum transition can be seen as a result of interference between various pathways(e.g. Feynman paths) which can be labelled by a variable $f$. An attempt to determine the value of f without destroying the coherence between the pathways…

Quantum Physics · Physics 2009-05-26 D. Sokolovski

That the laws of physics are the same at all times and places throughout the Universe is one of the basic assumptions of physics. Astronomical observations provide the only means to test this basic assumption on cosmological time and…

Instrumentation and Methods for Astrophysics · Physics 2019-04-10 Xi Chen , Simon P. Ellingsen , Ying Mei

The problem of detecting variance breaks in the case of smooth time-varying variance structure is studied. It is highlighted that the tests based on (piecewise) constant specification of the variance are not able to distinguish between…

Methodology · Statistics 2017-07-24 Ben Hajria Raja , Khardani Salah , Raïssi Hamdi

We identify two metastable excited states in Sm$ ^{10+} $ highly charged ion as candidates for high accuracy optical clocks. Several atomic properties relevant to optical clock development are calculated using relativistic many-body…

High Energy Physics - Phenomenology · Physics 2024-09-04 Saleh O. Allehabi , V. A. Dzuba , V. V. Flambaum

Astrophysical tests of the stability of Nature's fundamental couplings are a key probe of the standard paradigms in fundamental physics and cosmology. In this report we discuss updated constraints on the stability of the fine-structure…

High Energy Physics - Phenomenology · Physics 2015-08-26 S. M. João , C. J. A. P. Martins , I. S. A. B. Mota , P. M. T. Vianez

Transition frequencies of Fe II ion are known to be very sensitive to variation of the fine structure constant \alpha. The resonance absorption lines of Fe II from objects at cosmological distances are used in a search for the possible…

Atomic Physics · Physics 2009-11-13 S. G. Porsev , K. V. Koshelev , I. I. Tupitsyn , M. G. Kozlov , D. Reimers , S. A. Levshakov

In analogy to $f(R)$ theory, recently a new modified gravity theory, namely the so-called $f(T)$ theory, has been proposed to drive the current accelerated expansion without invoking dark energy. In the present work, by extending Bisabr's…

General Relativity and Quantum Cosmology · Physics 2011-08-25 Hao Wei , Xiao-Peng Ma , Hao-Yu Qi

Ultralight bosonic dark matter has come under increasing scrutiny as a dark matter candidate that has the potential to resolve puzzles in astronomical observation. We demonstrate that high-precision measurements of time variation in the…

High Energy Physics - Phenomenology · Physics 2023-12-08 Joshua Berger , Amit Bhoonah

Any slight variations in the fundamental constants of Nature, which may be induced by dark matter or some yet-to-be-discovered cosmic field, would characteristically alter the phase of a light beam inside an interferometer, which can be…

High Energy Physics - Phenomenology · Physics 2015-04-24 Y. V. Stadnik , V. V. Flambaum

Light traveling through the vacuum interacts with vacuum fluctuations similarly to the way that light traveling through a dielectric interacts with ordinary matter. And just as the permittivity of a dielectric can be calculated, the…

General Physics · Physics 2026-02-17 G. B. Mainland , Bernard Mulligan

By employing Dirac LNH, and a further generalization by Berman (GLNH), we estimate how should vary the total number of nucleons, the energy density, Newton Gravitational constant, the cosmological constant, the magnetic permeability and…

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

Changes in the values of the fundamental constants mu, the proton to electron mass ratio, and alpha, the fine structure constant due to rolling scalar fields have been discussed both in the context of cosmology and in new physics such as…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Rodger I. Thompson

Linearity is an important and frequently sought property in electronics and instrumentation. Here, we report a method capable of, given a transfer function, identifying the respective most linear region of operation with a fixed width. This…

Data Analysis, Statistics and Probability · Physics 2016-12-21 Filipi N. Silva , Cesar H. Comin , Luciano da F. Costa
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