Cosmological Constraints on Polytropic Gas Model

Cosmological Constraints From the Intracluster Gas Fraction

Polytropic Gas Dynamics

We give a Lax description for the system of polytropic gas equations. The special structure of the Lax function naturally leads to the two infinite sets of conserved charges associated with this system. We obtain closed form expressions for the conserved charges as well as the generating functions for them. We show how the study of these generating functions can naturally lead to the recursion ...

L∞ Solutions for a Model of Nonisothermal Polytropic Gas Flow

L∞ SOLUTIONS FOR A MODEL OF NONISOTHERMAL POLYTROPIC GAS FLOW∗ HERMANO FRID† , HELGE HOLDEN‡ , AND KENNETH H. KARLSEN‡ Abstract. We establish the global existence of L∞ solutions for a model of polytropic gas flow with varying temperature governed by a Fourier equation in the Lagrangian coordinates. The result is obtained by showing the convergence of a class of finite difference schemes, which...

Cosmological Constraints on Unparticles

We study the cosmological constraints on unparticle interactions and the temperature of the Universe for an unparticle sector with dimensional transmutation scale ΛU > ∼ 1 TeV. By considering thermal background quark decay to unparticles via a scalar operator of dimension dU , we show that the condition that the Universe is not dominated by unparticles at nucleosynthesis imposes a lower bound o...

Constraints on cosmological parameters

A cosmological model with total density close to critical (and flat geometry), dominated by dark matter and dark energy of unknown nature, and consistent with the basic predictions of the inflationary scenario is a very good fit to a variety of cosmological probes: the anisotropy of the CMB, the large scale distribution of matter, the luminosity distance of high-redshift type Ia supernovae and ...