منابع مشابه
Dark Energy Dominance and Cosmic Acceleration in First Order Formalism
The current accelerated universe could be produced by modified gravitational dynamics as it can be seen in particular in its Palatini formulation. We analyze here a specific non-linear gravity-scalar system in the first order Palatini formalism which leads to a FRW cosmology different from the purely metric one. It is shown that the emerging FRW cosmology may lead either to an effective quintes...
متن کاملFirst - order formalism for the quintom model of dark energy
The present paper deals to the quintom model of dark energy. We introduce a first-order formalism, which shows how to relate the potential that specifies the scalar field model to Hubble parameter. Reviewing briefly the quintom scenario of dark energy, we present a general procedure to solve the equations of motion for quintom model driven by a couple scalar fields with first-order differential...
متن کاملFirst-order Formalism and Odd-derivative Actions
In this pedagogical note, we discuss obstacles to the usual Palatini formulations of gauge and gravity theories in presence of odd-derivative order, Chern-Simons, terms.
متن کاملFirst order hyperbolic formalism for Numerical Relativity
The causal structure of Einstein’s evolution equations is considered. We show that in general they can be written as a first order system of balance laws for any choice of slicing or shift. We also show how certain terms in the evolution equations, that can lead to numerical inaccuracies, can be eliminated by using the Hamiltonian constraint. Furthermore, we show that the entire system is hyper...
متن کاملFirst order formalism for spin one field
We study two general approaches how to describe spin one particles, using vector and antisymmetric tensor fields within RχT. In this paper we focus on the question of an equivalence of both ways. The appearing problems lead us to the introduction of a new type of the description the first order formalism which naturally connects both traditional formalisms. Moreover, it gives a more general res...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Physics Letters B
سال: 2006
ISSN: 0370-2693
DOI: 10.1016/j.physletb.2005.12.031