Related papers: Vacuum decay in quadratic gravity
We study the decay of the false vacuum in the regime where the quantum field theory analysis is not valid, since gravitational effects become important. This happens when the height of the barrier separating the false and the true vacuum is…
We investigate a puzzle in the recent thermodynamics of scalar-tensor gravity, in which general relativity is a zero-temperature state of equilibrium and scalar-tensor gravity is the non-equilibrium configuration of an effective dissipative…
We investigate the metastability of scalar fields in quantum field theories at finite temperature, focusing on a detailed understanding of the bounce solution. At finite temperature, the bounce solution depends on two variables: the…
The tunneling wave function of the universe is calculated exactly for a de Sitter minisuperspace model with a massless conformally coupled scalar field, both by solving the Wheeler-DeWitt equation and by evaluating the Lorentzian path…
The standard bounce formalism for calculating the decay rate of a metastable vacuum cannot be applied to theories in which the symmetry breaking is due to radiative corrections, because in such theories the tree-level action has no bounce…
In the framework of asymptotic safety, we study quantum quadratic gravity in the presence of the Higgs field considered as non-separable from the vacuum. The theory flows to a high energy fixed point where the Higgs field is strongly…
We use some exact results in the scalar field theory to revise the analysis by Coleman and Callan about the false vacuum decay and propose a simple non-perturbative formalism. We introduce exact Green's function which incorporates…
The vacuum of quantum fields contains correlated fluctuations. When restricted to one side of a surface these have a huge entropy of entanglement that scales with the surface area. If UV physics renders this entropy finite, then a…
We investigate the emergence of a quantum Big-Bounce in the context of an isotropic Universe, filled by a self-interacting scalar field, which plays the role of a physical clock. The bouncing cosmology is the result of a scattering process,…
The vacuum transition probabilities for a Friedmann-Lema\^itre-Robertson-Walker universe with positive curvature in Ho\v{r}ava-Lifshitz gravity in the presence of a scalar field potential in the Wentzel-Kramers-Brillouin approximation are…
We develop a new iterative method for finding approximate solutions for spherical bounces associated with the decay of the false vacuum in scalar field theories. The method works for any generic potential in any number of dimensions,…
In this paper, we provide a vacuum solution with torsion in quadratic Riemann-curvature gravity. Physically, the solution means that vacuum can have a nonzero vacuum field with large torsion. We show that the Einstein-Hilbert action can be…
In the transition between inflation and reheating, the curvature scalar typically undergoes oscillations which have significant impact on the density of gravitationally produced particles. The commonly used adiabatic vacuum prescription for…
We prove the impossibility of resonant decay of a metastable vacuum in a theory of a scalar field coupled to a gauge field. Our result extends to gauge theories of scalar fields a recent no go theorem for resonant tunneling in a pure scalar…
The general thermodynamic analysis of the quantum vacuum, which is based on our knowledge of the vacua in condensed-matter systems, is consistent with the Einstein earlier view on the cosmological constant. In the equilibrium Universes the…
We present a study of the decay of metastable states of a scalar field via thermal activation, in the presence of a finite density of fermions. The process we consider is the nucleation of ``{\it droplets}'' of true vacuum inside the false…
We study the Euclidean bounce action interpolating between a false and a true vacuum for a scalar field theory with various types of potential. We focus on the cases of a triangular, a square and a quadratic barrier, where the bounce action…
We study the effects of internal symmetries on the decay by bubble nucleation of a metastable false vacuum. The zero modes about the bounce solution that are associated with the breaking of continuous internal symmetries result in an…
We study the equilibria of a self-gravitating scalar field in the region outside a reflecting barrier. By introducing a potential difference between the barrier and infinity, we create a kink which cannot decay to a zero energy state. In…
Temperature plays a crucial role in metastable phenomena, not only by contributing to determine the state (phase) of a system, but also ruling the decay probability to more stable states. Such a situation is encountered in many different…