Tags » Mathematical Physics

Dynamical symmetries and observational constraints in scalar field cosmology [CL]


We propose to use dynamical symmetries of the field equations, in order to classify the dark energy models in the context of scalar field (quintessence or phantom) FLRW cosmologies. 169 more words


Lattice Universe: examples and problems [CL]


We consider lattice Universes with spatial topologies $T\times T\times T$, $\; T\times T\times R\; $ and $\; T\times R\times R$. In the Newtonian limit of General Relativity, we solve the Poisson equation for the gravitational potential in the enumerated models. 142 more words


Why are sound waves longitudinal?

“Give me some example for waves in nature! “

“Sound is a wave.. Light is a wave.. Of course we see water waves.. “

Thats the usual answer we think about when asked that question.  541 more words

Longitudinal Waves

General Relativity and Gravitation: A Centennial Perspective [CL]


To commemorate the 100th anniversary of general relativity, the International Society on General Relativity and Gravitation (ISGRG) commissioned a Centennial Volume, edited by the authors of this article. 116 more words

High Energy Astrophysical Phenomena

A New Solution of Einstein Vacuum Field Equations [CL]


A new solution of Einstein’s vacuum field equations is discovered which appears as a generalization of the well-known Ozsvath-Schucking solution and explains its source of curvature which has otherwise remained hidden. 84 more words


Friedmann's Equations in All Dimensions and Chebyshev's Theorem [CEA]


This short but systematic work demonstrates a link between Chebyshev’s theorem and the explicit integration in cosmological time $t$ and conformal time $\eta$ of the Friedmann equations in all dimensions and with an arbitrary cosmological constant $\Lambda$. 191 more words

Cosmology And Nongalactic Astrophysics