Dark Matter and Dark Energy: a Scenario of Ac- celerating Universe
نویسندگان
چکیده
Dark matter, the major component of the matter content of the Universe, played a significant role at early stages during structure formation. But at present the Universe is dark energy dominated as well as accelerating. Here, the presence of dark matter has been established by including a time-dependent Λ term in the field equations. This model is compatible with the idea of an accelerating Universe so far as the value of the deceleration parameter is concerned.
منابع مشابه
Formation of Large Structures in the Acceleration Universe with a Hybrid Expansion Law
In the current paper, we have studied the effect of dark energy on for-mation where dark energy exists in the background. For this purpose, we used both WMAP9 and Planck data to study how the radius changes with redshift in these mod-els. We used different data sets to fix the cosmological parameters to obtain a solution for a spherical region under collapse. The mechanism of structure formation f...
متن کاملپیامدهای اختر فیزیکی ماده تاریک سرد
There are several observational evidences for the existence of dark matter in the universe. More than about 90% of the matter in the universe is in a form which is not directly observable. If the dark matter is in the form of weakly interacting massive particles (WIMPs) or cosmions, part of it is captured by the Sun, other stars, and even planets. In this paper, some basic ideas of the cosmio...
متن کاملSome studies on dark energy related problems
In this work we perform some studies related to dark energy. Firstly, we propose a dynamical approach to explain the dark energy content of the universe. We assume that a massless scalar field couples to the Hubble parameter with some Planck-mass suppressed interactions. This scalar field developes a Hubble parameter-dependent (thus time-dependent) vacum expectation value, which renders a time-...
متن کاملSimon Hot - dark matter , cold dark matter and accelerating universe
The Friedman equation is solved for a universe containing hot-dark matter and cold dark matter. In this scenario, hot-dark matter drives an accelerating universe no cold dark matter.
متن کاملCoupling dark energy to dark matter inhomogeneities
We propose that dark energy in the form of a scalar field could effectively couple to dark matter inhomogeneities. Through this coupling energy could be transferred to/from the scalar field, which could possibly enter an accelerated regime. Though phenomenological, this scenario is interesting as it provides a natural trigger for the onset of the acceleration of the universe, since dark energy ...
متن کاملذخیره 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 2005