In this work we study the properties of compact spheres made a charged perfect fluid with MIT bag model EoS for quark matter. Considering static spherically symmetric spacetime derive hydrostatic equilibrium equations in recently formulated four dimensional Einstein-Gauss-Bonnet ($4D$ EGB) gravity theory. setting, modified TOV are solved numerically aim to investigate impact electric charge on ...

These notes summarize the content of two of our papers dealing with two-dimensional (2D) dilaton gravity theories [1,2]. Our presentation in Santa Margherita was essentially based on the first paper [1], whereas the content of the second one [2] was briefly sketched as work in progress. For sake of completeness it seems to us advisable to give a full account of the recent results of Ref. [2] in...

In this note we give some remarks on the BRST formulation of a renormalizable and diffemorphism invariant 4D quantum gravity recently proposed by the author, which satisfies the integrability condition by Riegard, Fradkin and Tseytlin at the 2-loop level. Diffeomorphism invariance requires an addition of the Wess-Zumino action, from which the Weyl action can be induced by expanding around a vac...

Two kinds of statistical properties of dynamical-triangulated manifolds (DT mfds) have been investigated. First, the surfaces appearing on the boundaries of 3D DT mfds were investigated. The string-susceptibility exponent of the boundary surfaces (˜ γst) of 3D DT mfds with S 3 topology near to the critical point was obtained by means of a MINBU (minimum neck baby universes) analysis; actually, ...

We paste together patches of AdS6 to find solutions which describe two 4-branes intersecting on a 3-brane with non-zero tension. We construct explicitly brane arrays with Minkowski, de Sitter and Anti-de Sitter geometries intrinsic to the 3-brane, and describe how to generalize these solutions to the case of AdS4+n, n > 2, where n n + 2-branes intersect on a 3-brane. The Minkowski and de Sitter...

In this article we consider nonholonomic deformations of disk solutions in general relativity to generic off–diagonal metrics defining knew classes of exact solutions in 4D and 5D gravity. These solutions possess Lie algebroid symmetries and local anisotropy and define certain generalizations of manifolds with Killing and/ or Lie algebra symmetries. For Lie algebroids, there are structures func...

Using the background-metric independence for the traceless mode as well as the conformal mode, 4D quantum gravity is described as a quantum field theory defined on a non-dynamical backgroundmetric. The measure then induces an action with 4 derivatives. So we think that 4-th order gravity is essential and the Einstein-Hilbert term should be treated like a mass term. We introduce the dimensionles...

Dynamical triangulations of four-dimensional Euclidean quantum gravity give rise to an interesting, numerically accessible model of quantum gravity. We give a simple introduction to the model and discuss two particularly important issues. One is that contrary to recent claims there is strong analytical and numerical evidence for the existence of an exponential bound that makes the partition fun...

Permanent address: Institute of Physics, Jagellonian University, ul. Reymonta 4, 30-059 Kraków, Poland Laboratoire associé au CNRS. whether this finding does not reflect a deficiency of the simulation set-up. As it is an important question, we have decided to check it in more detail. The result of this investigation is presented in sect. 2 of this communication. In sect. 3 we also present some ...

Our earlier renormalization group study of simplicial gravity is extended and the evidence for the existence of an isolated ultra-violet fixed point is strengthened. A high statistics study of the volume and coupling constant dependence of the cumulants of the node distribution is carried out. It appears that the phase transition of the theory is of first order, contrary to what is generally be...