Related papers: Do Global String Loops Collapse to Form Black Hole…

To explain black hole thermodynamics in quantum gravity, one must introduce constraints to ensure that a black hole is actually present. I show that for a large class of black holes, such ``horizon constraints'' allow the use of conformal…

Recently Pen and Spergel (1997) have shown that a universe whose energy density is dominated by a frustrated network of non-Abelian TeV-scale cosmic strings could account for a broad class of cosmological observations. In this paper we…

For most black holes in string theory, the Schwarzschild radius in string units decreases as the string coupling is reduced. We formulate a correspondence principle, which states that (i) when the size of the horizon drops below the size of…

In this paper, we give a rigorous mathematical treatment of the late time Hawking radiation of massless bosons emitted by a class of collapsing, spherically symmetric, charged models of black hole formation, including both extremal and…

Loops formed from a cosmic string network at early times would act as seeds for early formation of halos, which would form galaxies and lead to early reionization. With reasonable guesses about astrophysical and string parameters, the…

We show that primordial black holes (PBHs) develop non-negligible spins through Hawking emission of the large number of axion-like particles generically present in string theory compactifications. This is because scalars can be emitted in…

Constraints on the tension and the abundance of cosmic strings depend crucially on the rate at which they decay into particles and gravitational radiation. We study the decay of cosmic string loops in the Abelian-Higgs model by performing…

The coupling of a string to gravity allows for Schwarzschild black holes whose entropy to area relation is $S=(A/4)(1-4\mu)$, where $\mu$ is the string tension. This departure from the A/4 universality results from a string instanton…

I review some recent work (done in collaboration with G. Veneziano) which clarifies the existence of a correspondence between self-gravitating fundamental string states and Schwarzschild black holes. The main result is a detailed…

Dark photon dark matter may be produced by the cosmic strings in association with the dark U(1) gauge symmetry breaking. We perform three-dimensional lattice simulations of the Abelian-Higgs model and follow the evolution of cosmic strings.…

In TeV-scale gravity scenarios with large extra dimensions, black holes may be produced at future colliders. Good arguments have been made for why general relativistic black holes may be just out of reach of the Large Hadron Collider (LHC).…

It is shown that the gravitational field, as a physical field developing in the Minkowsky space, does not lead to unlimited gravitational collapse of massive bodies and, hence, excludes a possibility of the formation of the ``black holes''.

We study the gravitational collapse of compact objects in the Brane-World. We begin by arguing that the regularity of the five-dimensional geodesics does not allow the energy-momentum tensor of matter on the brane to have (step-like)…

We consider modifications to general relativity due to non-local string effects by using perturbation theory about the 4-dimensional Schwarzschild black hole metric. In keeping with our interpretation in previous works of black holes as…

In this paper the currently held view that the endpoint of gravitational collapse is a singularity is refuted. A quantum mechanical calculation is done showing that spin 0 and spin 1/2 particles inside a black hole's schwarzschild radius…

A black hole is the end state of the gravitational collapse of massive stars. However, a typical black hole contains a singularity and to avoid singularity formation we have to violate a strong energy condition that states that gravity must…

Charged black holes, both spherically symmetric and rotating, in the low energy limit of string theory (Einstein-Maxwell-dilaton theory) are compared to analogous geometries in pure general relativity. We describe various physical…

One of the paradoxes associated with the theory of the formation and subsequent Hawking evaporation of a black hole is the disappearance of conserved global charges. It has long been known that metric fluctuations at short distances…

Particle emission, in addition to gravitational radiation from cosmic string loops, affects the resulting loop distribution and hence the corresponding observational consequences of cosmic strings. Here we focus on two models in which loops…

The phenomenon of string spreading on the black hole horizon, as originally discussed by Susskind, is considered in the {\it exact} curved Schwarzschild background. We consider an oscillating string encircling the black hole and contracting…