While it is widely believed that the gravitational collapse of a sufficiently large mass will lead to a density singularity and an event horizon, we propose that this never happens when quantum effects are taken into account. In particular, we propose that when the conditions become ripe for a trapped surface to form, a quantum critical surface sweeps over the collapsing body, transforming the nucleons in the collapsing matter into a lepton/photon gas together with a positive vacuum energy. This will happen regardless of the matter density at the time a trapped surface starts to form, and as a result we predict that at least in all cases of gravitational collapse involving ordinary matter, a large fraction of the rest mass of the collapsing matter will be converted into a burst of neutrinos, and γrays. We predict that the peak luminosity of these bursts is only weakly dependent on the mass of the collapsing object, and is on the order of (ε q /m P c 2 ) 1/4 c 5 /G, where ε q is the mean energy of a nucleon parton and m P is the Planck mass. The duration of the bursts will depend the mass of the collapsing objects; in the case of stellar core collapse we predict that the duration of both the neutrino and γ-ray bursts will be on the order of 10 seconds.The ultimate fate of matter undergoing gravitational collapse is a long standing enigma. Following the seminal paper of Oppenheimer and Snyder [1] it has come to be widely accepted that the gravitational collapse of a sufficiently large mass will

A sharp dip in the spectrum of γ rays coming from compact objects below 70 MeV would be an unambiguous signal that compact astrophysical objects have a physical surface, and there is no event horizon. Observation of this effect would open a window for the empirical study of Planck scale physics IntroductionBlack hole solutions of the classical Einstein equations pose a number of conceptual difficulties, not the least of which is incompatibility with elementary quantum mechanics. It has been suggested that in reality the interior of a compact object is a "squeezed" version of the ordinary space-time vacuum [1]. This led to the suggestion [2,3] that the surface separating the squeezed vacuum from the ordinary vacuum is a physical surface that produces observable effects rather than an event horizon. One of us (GC) has coined the name "dark energy star" for a compact object where this surface is a quantum critical layer [4]. In sharp contrast with the celebrated prediction of classical general relativity that nothing happens to particles as they fall through the event horizon, one finds that in the quantum criticality picture ordinary matter will undergo a dramatic transformation at the surface of a dark energy star. In particular, elementary particles whose initial momentum exceeds a characteristic value Q 0 , on the order of 100(M o /M) 1/2 MeV/c, where M is the mass of the compact object, will be strongly scattered and can decay into other elementary particles [5]. These interactions are similar to those experienced by quasiparticles in a quantum liquid near to a quantum critical point. A remarkable prediction of this quantum criticality picture is that protons hitting the surface of a compact astrophysical object will decay into positrons and mesons [5].It happens that the quarks and gluons inside nucleons typically have momenta that exceed Q 0 for all known compact objects, and therefore will undergo strong interactions at the surface if the surface is a quantum critical layer. In grand unified models of elementary particles such as the Georgi-Glashow SU(5) model [6] nucleon disappearance will then proceed via the baryon number violating reactions:

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The present day mass spectrum for dark matter compact objects is calculated based on the assumption that a uniform population of PBHs was created at a definite redshift with a uniform mass and that the mass spectrum evolved as a result of gravitational radiation. The predicted present day spectrum extends over many decades of mass and allows one to connect the abundance of MACHOs in the halo of our galaxy with the abundance of galactic seeds. Present day astrophysical constraints on the abundance of dark matter PBHs appear to be consistent with our predicted mass spectrum if it is assumed that the seeds for the present day dark matter MACHOs were created at a time ∼ 10 −4 seconds after the big bang. Remarkably the total cosmological energy density at this time obtained by extrapolating the sum of the present day dark matter and CMB energies backward in time and is very close to the mass-energy density in an Einstein-de Sitter universe at the same time. This suggests that the radiation precursor to the CMB was created at about the same time as the seeds for the present day dark matter.DOI: 10.31526/LHEP.1.2018.04Some time ago it was suggested [1], [2] that the dark matter component of the matter in today's universe might consist entirely of primordial black holes (PBHs). It was also pointed out [3] in a flat universe whose mass-energy density is dominated by primordial black holes it would perhaps be natural for all matter to eventually consist of horizon mass black holes. Of course these proposals begged the question as to why dark matter should consist of black holes rather than some other exotic form of non-baryonic matter such as WIMPs or axions. On the other hand the persistent failure to find any evidence for WIMPs or cosmic axions has perhaps tipped the balance in favor of PBHs [4], [5] In this letter we focus on the question of what the present day spectrum of dark matter compact objects might have to say about the form of matter near the onset of the big bang. We show that if an initially uniform population of PBHs evolves as a result of gravitational radiation during binary collisions, then the present day mass spectrum for primordial compact objects will smoothly interpolate between the MACHO objects which could form the halo of our galaxy [6] and the massive seeds for the compact objects at the center of galaxies [7], [8],[9]. This puts constraints on the redshift where the initial PBHs were formed, which naturally leads to the question as to the form matter took prior to this redshift. An intriguing possibility is that the PBH precursors to the present day MACHOs and the radiation precursors to CMB were both created at the same redshift by the release of entropy from massive compact objects created at the onset of the big bang.Our basic assumption is that the present day population of dark matter MACHOs evolved from an initial population of compact objects with nearly the same mass M DM created at a specific redshift z r .We will also assume that during the radiation dominated era z < z r the...