Stability of regular energy density in Palatini $$f(R)$$ f ( R ) gravity
نویسندگان
چکیده
منابع مشابه
Stability of Palatini-f(R) cosmology
The evolution of linear cosmological perturbations in modified theories of gravity is investigated assuming the Palatini formalism. It has been discussed about the stability problem in this model based on the equivalence between f(R) gravity and the scalar tensor theory. However, we study this problem in the physical frame where the matter is minimally coupled. In general, the stability of the ...
متن کاملGravitomagnetic effects in Palatini f(R) theories of gravity
We explicitly worked out the orbital effects induced on the trajectory of a test particle by the the weak-field approximation of the Kerr-de Sitter metric, which is a solution of vacuum f(R) field equations, in the Palatini formalism. It results that the node, the pericentre and the mean anomaly undergo secular precessions proportional to k, which is a measure of the non linearity of the theory...
متن کاملConstraining f(R) gravity in the Palatini formalism
Although several models of f(R) theories of gravity within the Palatini approach have been studied already, the interest was concentrated on those that have an effect on the late-time evolution of the universe, by the inclusion for example of terms inversely proportional to the scalar curvature in the gravitational action. However, additional positive powers of the curvature also provide intere...
متن کاملPalatini f(R) gravity as a fixed point
In the context of modified gravity, we point out how the Palatini version of these theories is singled out as a very special case corresponding to the unique fixed point of a transformation involving a special conformal rescaling of the metric. This mathematical peculiarity signals deeply rooted problems which make the theory unphysical. PACS: 04.50+h, 04.20.Cv, 04.20.Fy, 04.90.+e.
متن کاملA no-go theorem for polytropic spheres in Palatini f(R) gravity
Non-vacuum static spherically-symmetric solutions in Palatini f(R) gravity are examined. It is shown that for generic choices of f(R), there are commonly-used equations of state for which no satisfactory physical solution of the field equations can be found within this framework, apart from in the special case of General Relativity, casting doubt on whether Palatini f(R) gravity can be consider...
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: The European Physical Journal C
سال: 2015
ISSN: 1434-6044,1434-6052
DOI: 10.1140/epjc/s10052-015-3277-0