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Electromagnetic methods recently proposed for detecting gravitational waves modify the Michelson phase shift analysis (historically employed for special relativity). We suggest that a frequency modulation analysis is more suited to general…

General Relativity and Quantum Cosmology · Physics 2007-05-23 S. Sivasubramanian , Y. N. Srivastava , A. Widom

A new approach for arbitrary dimension to the Friedmann cosmological models is presented. Taking suitable changes of the parameters of the spacetime the harmonic motion equations appear, where the curvature determines the angular frequency.…

General Relativity and Quantum Cosmology · Physics 2014-03-03 Rafael M. Rubio , Juan J. Salamanca

Pulsar Timing Arrays have yet to convincingly observe gravitational waves. Some time ago it was pointed out by one of the authors that a dramatic enhancement of the signal would take place for particular values of the angle subtended by the…

General Relativity and Quantum Cosmology · Physics 2020-04-16 Domènec Espriu , Luciano Gabbanelli , Marc Rodoreda

We propose a time-dependent photonic structure, in which the carrier frequency of an optical pulse is shifted without changing its shape. The efficiency of the device takes advantage of slow group velocities of light attainable in periodic…

Other Condensed Matter · Physics 2009-11-11 Zeno Gaburro , Mher Ghulinyan , Francesco Riboli , Lorenzo Pavesi , Alessio Recati , Iacopo Carusotto

A class of coordinate systems is found for Friedmann Cosmologies with local gravity such that it is possible to formulate quantum theory over astronomical and cosmological distances. When light from distance objects is treated as a quantum…

General Physics · Physics 2009-04-28 Charles Francis

We analyze quantum effects occurring in optomechanical systems where the coupling between an optical mode and a mechanical mode is quadratic in displacement (membrane-in-the-middle geometry). We show that it is possible to observe quantum…

Quantum Physics · Physics 2019-05-08 J. D. P. Machado , R. J. Slooter , Ya. M. Blanter

We investigate the cosmological evolution of the luminosity and redshift of FRBs. As is the case for all extragalactic sources, we are dealing with data that are truncated by observational selection effects, the most important being the…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-05 Sujay Champati , Vahé Petrosian

Einstein's theory of general relativity states that clocks at different gravitational potentials tick at different rates - an effect known as the gravitational redshift. As fundamental probes of space and time, atomic clocks have long…

The Doppler shift is investigated in one-dimensional system with moving source. Theoretical findings are confirmed in numerical simulations of optical and acoustical waves propagation in simple metamaterial model, showing the reversed shift…

Optics · Physics 2015-06-23 David Ziemkiewicz , Sylwia Zielińska-Raczyńska

In this work, we derive a generalized modified Friedmann equation based on an entropy-area relation that incorporates established modifications, such as volumetric, linear, and logarithmic terms, in addition to novel entropic modifications…

General Relativity and Quantum Cosmology · Physics 2024-12-17 Javier Chagoya , I. Díaz-Saldaña , Mario H. Amante , J. C. López-Domínguez , M. Sabido

Employing a relativistic rotational transformation to study and analyze rotational phenomena, instead of the rotational transformations based on consecutive Lorentz transformations and Fermi coordinates, leads to different predictions. In…

General Relativity and Quantum Cosmology · Physics 2015-01-07 M. Nouri-Zonoz , H. Ramezani-Aval

This paper presents a completely analytic treatment of cosmological fluctuations whose wavelength is small enough to come within the horizon well before the energy densities of matter and radiation become equal. This analysis yields a…

Astrophysics · Physics 2009-11-07 Steven Weinberg

We analyse the Einstein equivalence principle (EEP) for a Hubble observer in Friedmann-Lemaitre-Robertson-Walker spacetime. We show that the affine structure of light cone in the FLRW spacetime should be treated locally in terms of the…

General Relativity and Quantum Cosmology · Physics 2014-02-05 Sergei Kopeikin

As the Universe expands, the redshift of distant sources changes with time. Here we discuss gravitational lensing phenomena that are consequence of the redshift drift between lensed source, gravitational lens, and observer. When the source…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-01 Giovanni Covone , Mauro Sereno

Using a fully gauge-invariant approach, we compute for the first time in the literature relativistic effects on the redshift drift up to second order in cosmological perturbation theory. This is achieved by employing a set of light-cone…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-30 Pierre Béchaz , Giuseppe Fanizza , Giovanni Marozzi , Matheus R. Medeiros Silva

We present frequency tunable metamaterial designs at terahertz (THz) frequencies using broadside-coupled split ring resonator (BC-SRR) arrays. Frequency tuning, arising from changes in near field coupling, is obtained by in-plane horizontal…

We generate a set of "relativistic" predictions for the relationship between viewing angle and apparent frequency, for each of three different non-transverse shift equations. We find that a detector aimed transversely (in the lab frame) at…

General Physics · Physics 2007-05-23 Eric Baird

We study the flight time fluctuations in an anisotropic medium inspired by a cosmic string with an effective fluctuating refractive index caused by fluctuating vacuum electric fields, which are analogous to the lightcone fluctuations due to…

General Relativity and Quantum Cosmology · Physics 2018-06-15 Jiawei Hu , Hongwei Yu

A photon source is located in a rotating waveguide. An absorber with a sharp absorbing frequency absorbs some of the emitted photons. This decreases the number of photons which are detected by a detector. The frequency (energy) spectrum…

Classical Physics · Physics 2022-11-24 M. Khorrami , A. H. Fatollahi , A. Shariati

When light travels through a medium in which the refractive index is rapidly changing with time, the light will undergo a shift in its frequency. Large frequency shifting effects have recently been reported for transparent conductive…

Optics · Physics 2021-12-20 Justus Bohn , Ting Shan Luk , Euan Hendry
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