Modified Friedmann equations from Debye entropic gravity
نویسندگان
چکیده
منابع مشابه
Cardassian Expansion: Dark Energy Density from Modified Friedmann Equations
The Cardassian universe is a proposed modification to the Friedmann equation in which the universe is flat, matter dominated, and accelerating. In the ordinary Friedmann equation, the right hand side is a linear function of the energy density, H ∼ ρ. Here, instead, the right hand side of the Friedmann equation is a different function of the energy density, H ∼ g(ρ). This function returns to ord...
متن کاملA Parameterized Post-Friedmann Framework for Modified Gravity
We develop a parameterized post-Friedmann (PPF) framework which describes three regimes of modified gravity models that accelerate the expansion without dark energy. On large scales, the evolution of scalar metric and density perturbations must be compatible with the expansion history defined by distance measures. On intermediate scales in the linear regime, they form a scalar-tensor theory wit...
متن کاملگرانش به عنوان نیروی آنتروپی و تاثیر آن بر تکینگیهای معادلات فریدمن
Interpretation of gravity as entropic force makes some corrections in Friedmann equations. According to calculations of Easson, Frampton and Smooth, the entropic force addss correction terms to Friedmann equations. It’s shown that these corrections change the second type of singularity to the third one in Friedmann equations. Considering Friedmann equations, even without entropic force at leas...
متن کاملFriedmann Equations of FRW Universe in Scalar - tensor Gravity , f ( R ) Gravity and First Law of
In the paper, hep-th/0501055 (R. it is shown that by applying the first law of thermodynamics to the apparent horizon of an FRW universe and assuming the geometric entropy given by a quarter of the apparent horizon area, one can derive the Friedmann equations describing the dynamics of the universe with any spatial curvature; using the entropy formula for the static spherically symmetric black ...
متن کاملA modified Friedmann equation
We recently formulated a model of the universe based on an underlying W3symmetry. It allows the creation of the universe from nothing and the creation of baby universes and wormholes for spacetimes of dimension 2, 3, 4, 6 and 10. Here we show that the classical large time and large space limit of these universes is one of exponential fast expansion without the need of a cosmological constant. U...
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: General Relativity and Gravitation
سال: 2012
ISSN: 0001-7701,1572-9532
DOI: 10.1007/s10714-012-1330-y