相关论文: On the ghost issue of extended quasidilaton

This note is devoted to the Hamiltonian analysis of extension of quasidilaton massive gravity as was proposed recently in [arXiv:1306.5502]. We show that for given formulation of the theory the additional primary constraint that is…

We present a novel cosmological solution in the framework of extended quasidilaton theory which underwent scrutiny recently. We only consider terms that do not generate the Boulware-Deser degree of freedom, hence the "ghost-free"…

In the extended quasidilaton massive gravity we perform a nonlinear transformation of the shift vector and then calculate the second derivatives of the Hamiltonian density with respect to the lapse function and the (nonlinearly transformed)…

In this work we study the partially constrained vielbein formulation of the new quasidilaton theory of massive gravity which couples to both physical and fiducial metrics simultaneously via a composite effective metric. This formalism…

An extension of the bimetric theory of gravity is considered that includes quadratic Ricci curvature terms associated with each metric. The issue of the Boulware-Deser ghost is analyzed. The Hamiltonian constraint is derived and the…

We study cosmological perturbations around self-accelerating solutions to two extensions of nonlinear massive gravity: the quasi-dilaton theory and the mass-varying theory. We examine stability of the cosmological solutions, and the extent…

A theory of the quasidilaton is an extension of massive gravity by a scalar field, nonlinearly realizing a certain new global symmetry of the Lagrangian. It has been shown that unlike pure massive gravity, this theory does admit homogeneous…

It is shown by an explicit calculation that the excitations about the self-accelerating cosmological solution of the Dvali--Gabadaze--Porrati model contain a ghost mode. This raises serious doubts about viability of this solution. Our…

In this work we study the theory of extended quasidilaton massive gravity together with the presence of matter fields. After discussing the homogeneous and isotropic fully dynamical background equations, which governs the exact expansion…

We present a review of cosmological solutions in non-linear massive gravity, focusing on the stability of perturbations. Although homogeneous and isotropic solutions have been found, these are now known to suffer from either Higuchi ghost…

We analyze the Extended Quasi-Dilaton Massive Gravity model around a Friedmann-Lema\^itre-Robertson-Walker cosmological background. We present a careful stability analysis of asymptotic fixed points. We find that the traditional fixed point…

We consider the stability of self-accelerating solutions to extended quasidilaton massive gravity in the presence of matter. By making a second or extended fiducial metric dynamical in this model, matter can cause it to evolve from a…

We investigate the stability against inhomogeneous perturbations and the appearance of ghost modes in Gauss-Bonnet gravitational theories with a non-minimally coupled scalar field, which can be regarded as either the dilaton or a…

Ghost inflation is a well-known framework in which cosmological fluctuations can generate enhanced primordial non-Gaussianity, typically of the equilateral type. In its original form, however, it is in tension with current observational…

We study the propagation of super-horizon cosmological perturbations in a non-singular bounce spacetime. The model we consider combines a ghost condensate with a Galileon term in order to induce a ghost-free bounce. Our calculation is…

We present the cosmological analysis of the Gauss-Bonnet quasi-dilaton massive gravity theory. This offers a gravitational theory with a non-zero graviton mass. We calculate the complete set of background equations of motion. Also, we…

The covariant St\"{u}ckelberg formalism is applied to bi-gravity in order to revisit the issue of absence of the Boulware-Deser (BD) ghost. We first confirm that the leading order action in the decoupling limit for helicity-2 modes of…

Recently, several works have investigated the coupling to matter in ghost-free massive (bi-&multi-)gravity and a new effective coupling to matter has been proposed. In this note we clarify some confusion on the existence and the…

We analyze the ghost issue in the recently proposed models of non-linear massive gravity in the ADM formalism. We show that, in the entire two-parameter family of actions, the Hamiltonian constraint is maintained at the complete non-linear…

We investigate cosmological behavior in the quasi-Dilaton non-linear massive gravity. We perform a detailed dynamical analysis and examine the stable late-time solutions relevant to late time cosmic acceleration. We demonstrate that a…