Connections between Abstract Quantum Theory and Space-Time-Structure. III. Vacuum Structure and Black Holes (original) (raw)

From the black hole conundrum to the structure of quantum gravity

Modern Physics Letters A

We portray the structure of quantum gravity emerging from recent progress in understanding the quantum mechanics of an evaporating black hole. Quantum gravity admits two different descriptions, based on Euclidean gravitational path integral and a unitarily evolving holographic quantum system, which appear to present vastly different pictures under the existence of a black hole. Nevertheless, these two descriptions are physically equivalent. Various issues of black hole physics — including the existence of the interior, unitarity of the evolution, the puzzle of too large interior volume, and the ensemble nature seen in certain calculations — are addressed very differently in the two descriptions, still leading to the same physical conclusions. The perspective of quantum gravity developed here is expected to have broader implications beyond black hole physics, especially for the cosmology of the eternally inflating multiverse.

A Form of Quantum Gravity Unification with the General Theory of Relativity

A form of Quantum gravity unification with the General theory of Relativity, 2024

The problem still remains (in theoretical physics) of how gravity can be unified with quantum mechanics, in as much as it would be possible to explain a consistent theory of quantum gravity. Which, this unification theory should (to a sufficient extent) adhere to the Friedmann-Lemaitre-Robertson-Walker metric. In the preceding work, a universal model is formulated, considering the results of the theory of quantum gravity, as well as the General theory of relativity. The space-time continuum is modelled to arise from the gravity quanta. This is by allowing the universe to retain its homogeneous nature at scales near the plank scale in (relativistic) difference from the time of the Big Bang and treating the gravity particle as behaving, both as a wave and as a particle (as of the theory of wave-particle duality). Once space-time is modelled, the field equations of general relativity are considered, and briefly mentioned, in the modelling of repulsive gravity as being the cause of the expansion of the universe. The space-time metric is considered, as possibly moving at faster than the speed of light. This is considered as suggesting, an event (as of the Special theory of relativity) of which its occasion supersedes the symmetry of which the Special theory of relativity was modelled, this is considered with no changes to the frame of reference of the Special theory of relativity.

Spacetime and the Philosophical Challenge of Quantum Gravity

1999

We survey some philosophical aspects of the search for a quantum theory of gravity, emphasising how quantum gravity throws into doubt the treatment of spacetime common to the two `ingredient theories' (quantum theory and general relativity), as a 4-dimensional manifold equipped with a Lorentzian metric. After an introduction, we briefly review the conceptual problems of the ingredient theories and introduce the enterprise of quantum gravity We then describe how three main research programmes in quantum gravity treat four topics of particular importance: the scope of standard quantum theory; the nature of spacetime; spacetime diffeomorphisms, and the so-called problem of time. By and large, these programmes accept most of the ingredient theories' treatment of spacetime, albeit with a metric with some type of quantum nature; but they also suggest that the treatment has fundamental limitations. This prompts the idea of going further: either by quantizing structures other than t...

Quantum Mechanical Black Holes: Towards a Unification of Quantum Mechanics and General Relativity

1998

In this paper, starting from vortices we are finally lead to a treatment of Fermions as Kerr-Newman type Black Holes wherein we identify the horizon at the particle's Compton wavelength periphery. A naked singularity is avoided and the singular processes inside the horizon of the Black Hole are identified with Quantum Mechanical effects within the Compton wavelength. Inertial mass, gravitation,

Quantum gravity as the unification of general relativity and quantum mechanics

2020

A nonstandard viewpoint to quantum gravity is discussed. General relativity and quantum mechanics are to be related as two descriptions of the same, e.g. as Heisenberg's matrix mechanics and Schrödinger's wave mechanics merged in the contemporary quantum mechanics. From the viewpoint of general relativity one can search for that generalization of relativity implying the invariance "within-out of" of the same system.

Against the disappearance of spacetime in quantum gravity

Synthese, 2019

This paper argues against the proposal to draw from current research into a physical theory of quantum gravity the ontological conclusion that spacetime or spatiotemporal relations are not fundamental. As things stand, the status of this proposal is like the one of all the other claims about radical changes in ontology that were made during the development of quantum mechanics and quantum field theory. However, none of these claims held up to scrutiny as a consequence of the physics once the theory was established and a serious discussion about its ontology had begun. Furthermore, the paper argues that if spacetime is to be recovered through a functionalist procedure in a theory that admits no fundamental spacetime, standard functionalism cannot serve as a model: all the known functional definitions are definitions in terms of a causal role for the motion of physical objects and hence presuppose spatiotemporal relations.

New Quantum Structure of Space-Time

Gravitation & Cosmology, 2019

We go beyond the classical-quantum duality of the space-time recently discussed and promote the space-time coordinates to quantum non-commuting operators. Comparison to the harmonic oscillator (X, P) variables and global phase space is enlighting. The phase space instanton (X, P = iT) describes the hyperbolic quantum space-time structure and generates the quantum light cone. The classical Minkowski space-time null generators X = ±T dissapear at the quantum level due to the relevant [X, T ] conmutator which is always non-zero. A new quantum Planck scale vacuum region emerges. We describe the quantum Rindler and quantum Schwarzshild-Kruskal space-time structures. The horizons and the r = 0 space-time singularity are quantum mechanically erased. The four Kruskal regions merge inside a single quantum Planck scale world. The quantum space-time structure consists of hyperbolic discrete levels of odd numbers (X 2 − T 2) n = (2n + 1) (in Planck units), n = 0, 1, 2.... .(X n , T n) and the mass levels being (2n + 1). A coherent picture emerges: large n levels are semiclassical tending towards a classical continuum spacetime. Low n are quantum, the lowest mode (n = 0) being the Planck scale. Two dual (±) branches are present in the local variables (√ 2n + 1 ± √ 2n) reflecting the duality of the large and small n behaviours and covering the whole mass spectrum: from the largest astrophysical objects in branch (+) to the quantum elementary particles in branch (-) passing by the Planck mass. Black holes belong to both branches (±). Starting from quantum theory (instead of general relativity) to approach quantum gravity within a minimal setting reveals successful: quantum relativity and quantum space-time structure are described. Further results are reported in another paper.

Quantum Geometrization of Spacetime in General Relativity

The primary aim of this study is to establish a unified criterion for obtaining the gravity developed by quantum mass densities within spacetime. This is achieved by extending the principle of equivalence between inertial and gravitational mass, a fundamental aspect of General Relativity, to the covariance of equations of motion. In the classical scenario, we obtain the gravity of spacetime with classical characteristics, whereas in the quantum scenario, we obtain the gravity of spacetime with quantum mechanical properties. In both cases, the principle of least action is employed to define the geometry of spacetime. The gravity resulting from the quantum geometrization of spacetime can be seen as the quantum mechanical counterpart of General Relativity, where the fields of quantum physics are integrated into the theory of gravitation. In this study, we derive the gravity generated by boson and fermion fields. The outcomes of the theory have been utilized to derive antimatter gravity, resolve black hole singularities, and understand the origin of small-valued cosmological constants. The work also derives the fluctuations of the black hole quantum potential in the presence of the gravitational wave background and evaluates the resultant repulsive gravity at large distances. Furthermore, it examines the breaking of the matter-antimatter symmetry caused by the gravitational coupling of the fermions field. The significance of matter-antimatter asymmetry in pre-big bang black hole is described: This behavior implies that the matter-antimatter asymmetry might have played a crucial role in the highly energetic vacuum states of the pre-big bang black hole. When surpassing the Planck mass, the high-energy fermion state in the pre-big bang black hole's comprised fermion and antifermion black holes. The annihilation of these black holes emitted lighter fermions, accounting for the mass difference between the black hole and anti-black hole. The theory shows that as we approach the Minkowskian limit, the matter-antimatter symmetry becomes asymptotically established, and the mass disparity between particles and antiparticles diminishes as we transition from heavier to lighter particles within each particle family. The theory also shows that if antimatter symmetry were upheld, the vacuum would have collapsed into the polymer branched phase because there would have been no residual mass (resulting from the matter-antimatter difference) to stabilize the vacuum and confer a nonzero cosmological constant. Thus, the matter-antimatter symmetry in a quantum mechanical covariant gravity is incongruent with the formation of a physically stable vacuum with non-zero mean cosmological constant value. The process of quantum geometrization of spacetime provides a comprehensive framework for understanding the evolution of our universe, from the Pre-big bang black hole to the current quantum-decoherent classical reality. The theory posits that the ubiquitous presence of supermassive black holes (SMBHs) at the centers of galaxies is a direct consequence of the big-bang, from which SMBHs are generated without mass accretion, and that it plays a pivotal role in cosmological expansion, driven by their repulsive interactions. Finally, the system of field equations for Quantum Electrodynamics (QED) in curved spacetime (containing the fields back-reaction), along with an introductory section on the Standard Model in self-generated gravity is presented. The problem of second quantization of fields in spacetime with the coupled gravity of is also introduced. This has the potential to extend the standard Quantum Field Theory (QFT) to high energies. Experimental tests examining the disparities in magnetic moments between leptons and antileptons, as well as investigations involving entangled photons, are proposed as potential avenues for empirically validating the theory.

Quantum spacetime: what do we know

I discuss nature and origin of the problem of quantum gravity. I examine the knowledge that may guide us in addressing this problem, and the reliability of such knowledge. In particular, I discuss the subtle modification of the notions of space and time engendered by general relativity, and how these might merge into quantum theory. I also present some reflections on methodological questions, and on some general issues in philosophy of science which are are raised by, or a relevant for, the research on quantum gravity.