A Grassmann Representation of the Hubble Parameter and the Cosmological Acceleration

نویسندگان

  • HARET C. ROSU
  • Haret C. Rosu
  • Jose Torres
چکیده

The Riccati equation for the Hubble parameter H of barotropic FRW cosmologies in conformal time for κ 6= 0 spatial geometries and in comoving time for the κ = 0 geometry, respectively, is generalized to odd Grassmannian time parameters. We obtain a system of simple differential equations for the four supercomponents (two of even type and two of odd type) of the Hubble superfield function H that is explicitly solved. For the interesting physical case of flat cosmologies, we obtain cosmological acceleration in the second even Hubble component for all values of the adiabatic index.

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

A Grassmann Representation of the Hubble Parameter

The Riccati equation for the Hubble parameter H of barotropic FRW cosmologies in conformal time for κ 6= 0 spatial geometries and in comoving time for the κ = 0 geometry, respectively, is generalized to odd Grassmannian time parameters. We obtain a system of simple differential equations for the four supercomponents (two of even type and two of odd type) of the Hubble superfield function H that...

متن کامل

Irreversible Processes in Inflationary Cosmological Models

By using the thermodynamic theory of irreversible processes and Einstein general relativity, a cosmological model is proposed where the early universe is considered as a mixture of a scalar field with a matter field. The scalar field refers to the inflaton while the matter field to the classical particles. The irreversibility is related to a particle production process at the expense of the gra...

متن کامل

Halting eternal acceleration with an effective negative cosmological constant

In order to solve the problem of eternal acceleration, a model has been recently proposed including both a negative cosmological constant Λ and a scalar field evolving under the action of an exponential potential. We further explore this model by contrasting it against the Hubble diagram of Type Ia supernovae, the gas mass fraction in galaxy clusters and the acoustic peak and shift parameters. ...

متن کامل

Inflaton field governed universe from NKK theory of gravity : stochastic approach

Inflaton field governed universe from NKK theory of gravity: stochastic approach. Abstract We study a nonperturbative single field (inflaton) governed cosmological model from a 5D Noncompact Kaluza-Klein (NKK) theory of gravity. The inflaton field fluctuations are estimated for different epochs of the evolution of the universe. We conclude that the inflaton field has been sliding down its (quad...

متن کامل

field governed universe from NKK theory of gravity : stochastic approach

Inflaton field governed universe from NKK theory of gravity: stochastic approach. Abstract We study a nonperturbative single field (inflaton) governed cosmological model from a 5D Noncompact Kaluza-Klein (NKK) theory of gravity. The inflaton field fluctuations are estimated for different epochs of the evolution of the universe. We conclude that the inflaton field has been sliding down its (quad...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2001