By boosting the vertex operators of Witten's S L(2; R)=U (1) black hole, we show that in the region V they lead to the primary elds of c = 1 matter coupled to gravity at nonzero cosmological constant, while there is no such correspondence in the region I, showing that Witten's black hole corresponds to 2d gravity only in a certain region and in a speciic limit. By using the free eld representat...

Two-dimensional Maxwell-dilaton quantum gravity on AdS2 with radius l and a constant electric field E is studied. In conformal gauge, this is equivalent to a CFT on a strip. In order to maintain consistent boundary conditions, the usual conformal diffeomorphisms must be accompanied by a certain U(1) gauge transformation. The resulting conformal transformations are generated by a twisted stress ...

Large contributions to the near closure of the Universe and to the acceleration of its expansion are due to the gravitation of components of the stress–energy tensor other than its mass density. To familiarize astronomers with the gravitation of these components we conduct thought experiments on gravity, analogous to the real experiments that our forebears conducted on electricity. By analogy t...

With the goal of studying cosmological constant (CC) problem, we present an exhaustive analysis unimodular gravity as a possible candidate to resolve CC origin and with this, current Universe acceleration. In this theory, correction (CC-like) in field equations sources late cosmic This is related new parameter, zini, which interpreted redshift CC-like emergence. By comparing value obtained from...

In this paper we introduce a new approach to the deformation of surface and raster models in two and three dimensions. Rather then deforming the objects in the model, we deform the rays used to render the scene. The mechanism to specify the deformation, which we call a deflector, is a vector of gravity positioned in space. This gravity vector bends any ray that travels through its field of grav...

One of the most intriguing unsolved problems in modern cosmology involves the nature of the observed dark matter in the universe. Various hypothetical particles have been postulated as the source of the dark matter, but as of yet none of these particles have been observed. In this paper I present an alternative view. The observations indicate the presence of a new force that is much weaker than...

Counteracting the destabilizing force of gravity is usually considered to be the main purpose of postural control. However, from the consideration of the mechanical requirements for movement, we argue that posture is adjusted in view of providing impetus for movement. Thus, we show that the posture that is usually adopted in quiet standing in fact allows torque for potential movement. Moreover,...

It is shown that the addition of a topological invariant (Gauss-Bonnet term) to the anti-de Sitter (AdS) gravity action in four dimensions recovers the standard regularization given by holographic renormalization procedure. This crucial step makes possible the inclusion of an odd parity invariant (Pontryagin term) whose coupling is fixed by demanding an asymptotic (anti)self-dual condition on t...