Quantum theory, black holes and quantum gravity

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Recent gravitational wave detections suggest that the promise of a new observational window on the universe is being realized. The first of these observations, namely the 2016 detection of gravitational waves emitted a billion years ago by the merger of two black holes, provided astounding confirmation of the validity of Einstein's theory of gravity in the strong field region as well as the first direct evidence for the existence of black holes. According to Einstein's theory, at the center of every black hole there exists a singularity, a region of high density and curvature where the known laws of physics break down. In 1976 Hawking showed that quantum processes allow energy to leak out of black holes in the form of thermal radiation. This causes the black hole to shrink and potentially disappear without revealing anything about the initial state of the matter that formed the black hole, thereby irreversibly destroying information. The presence of singularities and the possibility of information loss are issues that can only be resolved once quantum mechanics and gravity are successfully unified into a complete theory that makes falsifiable predictions. In the absence of such a theory, one must obtain insights from models designed to contain as many essential features of the full theory as possible while being tractable mathematically. My research will focus on the quantum behaviour of black holes in the context of such models. My long term goal is to find generic properties that would allow robust and ultimately observable predictions for quantum corrections to strong field black hole dynamics and evaporation. Specific topics include: the dynamics of nonsingular black hole formation and evaporation within a new class of effective spherical models; the quantum mechanics of a large variety of spherical black holes, including the energy spectrum and dynamics of singularity resolution; a quantum field theory model for the formation of shells of energy (``firewalls”) that are designed to partially solve the black hole information loss problem by preventing information from disappearing below the event horizon; a study of flow equations, a form of generalized heat equation, in the context of holographic descriptions of various physical systems such as superconductors and the quark-gluon plasma.******Benefit to Canada: This work will provide students with physics training, research experience and problem solving skills that will greatly expand their career options. It will also move us towards the next paradigm-shifting breakthrough in physics: a consistent and verifiable quantum theory of gravity. It is impossible to predict when such breakthroughs will occur, but when they do, they change our view of the world and give rise to unforeseeable and invaluable technological advances.