Results 121 to 130 of about 60,199 (278)

On the Perturbed Friedmann Equations in Newtonian Gauge

Universe
Based on Newtonian mechanics, in this article, we present a heuristic derivation of the Friedmann equations, providing an intuitive foundation for these fundamental relations in cosmology.
Jaume de Haro, Emilio Elizalde, Supriya Pan   +2 more
doaj   +1 more source

Matter instabilities in general Gauss-Bonnet gravity

, 2010
We study the evolution of cosmological perturbations in f(G) gravity, where the Lagrangian is the sum of a Ricci scalar R and an arbitrary function f in terms of a Gauss-Bonnet term G.
Antonio De Felice, David F. Mota, S. Capozziello, Shinji Tsujikawa   +3 more
core   +1 more source

Whipped and Mixed Warm Clouds in the Deep Sea

Geophysical Research Letters, Volume 53, Issue 2, 28 January 2026.
Abstract Turbulence is indispensable to redistribute nutrients for all life forms larger than microbial, on land and in the ocean. Yet, the development of deep‐sea turbulence was not studied in three dimensions to date. As a disproportionate laboratory, an array of nearly 3,000 high‐resolution temperature sensors had been installed for three years on ...
Hans van Haren, KM3NeT collaboration
wiley   +1 more source

Cosmology of a higher derivative scalar theory with non-minimal Maxwell coupling

European Physical Journal C: Particles and Fields, 2019
Higher derivative scalar field theory in curved space-time belongs to the GLPV theory coupled non-minimally to the Maxwell field is considered. We will show that the theory admits two independent exact de Sitter solutions in the FRW background, one ...
Shahab Shahidi
doaj   +1 more source

Vector disformal transformation of cosmological perturbations [PDF]

, 2018
Vassilis Papadopoulos, Moslem Zarei, Hassan Firouzjahi, Shinji Mukohyama   +3 more
openalex   +1 more source

Coordinate‐ and Spacetime‐Independent Quantum Physics

Annalen der Physik, Volume 538, Issue 1, January 2026.
This article studies in the framework of quantum field theory in curved spacetime, if there exists a single zero‐rank‐tensor solution of a Klein‐Gordon PDE, being valid at once for the depicted spacetimes. The answer is shown to be affirmative, even for a class of such solutions having the standard applications in particle physics. ABSTRACT The concept
Viacheslav A. Emelyanov, Daniel Robertz
wiley   +1 more source

Axial gravitational normal modes of uniform density star in Anti-de Sitter spacetime

Nuclear Physics B
The article studies the dynamical behavior of axial gravitational perturbations of homogeneous stars in Anti-de Sitter spacetime. Because the radial coordinate r transforms into the tortoise coordinate y=y(r), obeying y(r=0)=0 and y(r ...
Kai Lin, Alan B. Pavan, Amilcar Rabelo De Queiroz, Elcio Abdalla   +3 more
doaj   +1 more source

Multiple-scales analysis of cosmological perturbations in brane-worlds [PDF]

, 2004
Richard A. Battye, Andrew Mennim
openalex   +1 more source

Quantum GraviElectro Dynamics

Annalen der Physik, Volume 538, Issue 1, January 2026.
The BRST invariant Lagrangian of the gravitationally interacting U(1)$U(1)$ gauge theory, namely the Quantum GraviElectro Dynamics (QGED). The Yan–Mills theory with the Hilbert–Einstein gravitational Lagrangian, namely the Yang–Mills–Utiyama (YMU) theory, is defined and quantised using the standard procedure. The theory is perturbatively renormalisable,
Yoshimasa Kurihara
wiley   +1 more source

Logarithmic and Strong Coupling Models in Weyl‐Type f(Q,T)$f(Q,T)$ Gravity

Annalen der Physik, Volume 538, Issue 1, January 2026.
This work explores Weyl‐type f(Q,T) gravity using recent observational datasets — CC, Pantheon+, Union 3.0, and DESI DR2. Through MCMC analysis of logarithmic and strong coupling models, the study reveals a transition from deceleration to acceleration, quintessence‐to‐phantom dynamics, and late‐time consistency with LCDM, offering a geometry‐driven ...
Rahul Bhagat, S. K. Tripathy, B. Mishra
wiley   +1 more source