Expanding space-time and variable vacuum energy

نویسندگان

چکیده

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

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Space-Time Duality and Vacuum Energy

The concept of Euclidean time is proposed which is dual to the usual Minkowski time. The De Sitter solution is shown to be dual to the anti-De Sitter solution under the dual transformation in which Euclidean time and Minkowski time are interchanged. This observation enables us to make a proposal in which the supersymmetry is broken, but the four dimensional cosmological constant remains zero. A...

متن کامل

On the Vacuum Energy in Expanding Space-Times

If there is a shortest length in nature, for example at the Planck scale of 10m, then the cosmic expansion should continually create new comoving modes. A priori, each of the new modes comes with its own vacuum energy, which could contribute to the cosmological constant. I discuss possible mathematical models for a shortest length and an explicit model for a corresponding mode-generating mechan...

متن کامل

Finite time vacuum survival amplitude and vacuum energy decay

The problem of the vacuum energy decay is studied for both signs of the cosmological constant, through the analysis of the vacuum survival amplitude, defined in terms of the conformal time, z, by Aðz; z0Þ hvac zjvac z0i. Transition amplitudes are computed for finite time span, Z z0 z, and their late time behavior (directly related to the putative decay width of the state), and the transients ar...

متن کامل

Interacting realization of cosmological singularities with variable vacuum energy

We examine an interacting dark matter–variable vacuum energy model for a spatially flat Friedmann-Roberston-Walker spacetime, focusing on the appearance of cosmological singularities such as big rip, big brake, big freeze, and big separation along with abrupt events (infinite γsingularity and new w-singularity) at late times. We introduce a phenomenological interaction which has a nonlinear dep...

متن کامل

Accelerated expansion from braneworld models with variable vacuum energy

In braneworld models a variable vacuum energy may appear if the size of the extra dimension changes during the evolution of the universe. In this scenario the acceleration of the universe is related not only to the variation of the cosmological term, but also to the time evolution of G and, possibly, to the variation of other fundamental “constants” as well. This is because the expansion rate o...

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

ژورنال

عنوان ژورنال: Journal of Physics: Conference Series

سال: 2017

ISSN: 1742-6588,1742-6596

DOI: 10.1088/1742-6596/880/1/012024