An upper limit to the lifetime of stellar remnants from gravitational pair production

Abstract

Black holes are assumed to decay via Hawking radiation. Recently we found evidence that spacetime curvature alone without the need for an event horizon leads to black hole evaporation. Here we investigate the evaporation rate and decay time of a non-rotating star of constant density due to spacetime curvature-induced pair production and apply this to compact stellar remnants such as neutron stars and white dwarfs. We calculate the creation of virtual pairs of massless scalar particles in spherically symmetric asymptotically flat curved spacetimes. This calculation is based on covariant perturbation theory with the quantum field representing, e.g.,\ gravitons or photons. We find that in this picture the evaporation timescale, $\tau$, of massive objects scales with the average mass density, $\rho$, as $\tau \propto {\rho }^{-3/2}$. The maximum age of neutron stars, $\tau \sim 10^{68}\text{yr}$, is comparable to that of low-mass stellar black holes. White dwarfs, supermassive black holes, and dark matter supercluster halos evaporate on longer, but also finite timescales. Neutron stars and white dwarfs decay similarly to black holes, ending in an explosive event when they become unstable. This sets a general upper limit for the lifetime of matter in the universe, which in general is much longer than the Hubble--Lemaître time, although primordial objects with densities above ${\rho }_{\text{max}}\approx 3\times 10^{53}\text{g/}{\text{cm}}^3$ should have dissolved by now. As a consequence, fossil stellar remnants from a previous universe could be present in our current universe only if the recurrence time of star forming universes is smaller than about $\sim 10^{68}\text{years}$.

arXiv comment14 pages, 7 figures. Version accepted for publication in JCAP

References in corpus (23)

• Hawking Radiation as Tunneling
• Neutron Star Structure and the Equation of State
• Testing the nature of dark compact objects: a status report
• The Casimir force between real materials: experiment and theory
• Proton stability in grand unified theories, in strings, and in branes
• A Dying Universe: The Long Term Fate and Evolution of Astrophysical Objects
• Essential and inessential features of Hawking radiation
• Observation of Incipient Black Holes and the Information Loss Problem
• Quantum Corrected Black Holes from String T-Duality
• The black hole quantum atmosphere
• On the non-local heat kernel expansion
• Predictions from Star Formation in the Multiverse
• Gravitational Pair Production and Black Hole Evaporation
• Probing the Unruh effect with an accelerated extended system
• Galaxy Formation Efficiency and the Multiverse Explanation of the Cosmological Constant with EAGLE Simulations
• The Quantum Atmosphere of Reissner-Nordström Black Holes
• The universality of black hole thermodynamics
• Particle production in time-dependent gravitational fields: the expanding mass shell
• Black Dwarf Supernova in the Far Future
• Measuring the mass function of isolated stellar remnants with gravitational microlensing. II. Analysis of the OGLE-III data
• Conformal anomaly and gravitational pair production
• Thermal Neutrinos from the Explosion of a Minimum-Mass Neutron Star
• Reply to "Comment on 'Gravitational Pair Production and Black Hole Evaporation'"