Scattering in Quantum Gravity: Symmetries and Holography

New York University, New York NY

Investigators

Abstract

This award funds the research activities of Professor Monica Pate at New York University. The formulation of a complete theory unifying quantum mechanics and gravity remains a fundamental open problem at the forefront of modern physics. The subject of quantum gravity not only holds great significance for our understanding of the natural world, but also presents unique challenges that drive a quest for entirely new principles of physics. Remarkably, a new principle known as holography has emerged as a potential solution. At present, the holographic principle is the conjecture that systems of quantum gravity are equivalent to ordinary physical systems without gravity in fewer dimensions. This idea is similar to how every detail in a holographic projection is precisely captured on the corresponding holographic plate. While meaningful progress in quantum gravity has arisen from concrete realizations of the holographic principle, many fundamental aspects of the subject remain unresolved. Notably, we lack definitive predictions for a hypothetical particle collider that is powerful enough to probe the gravitational force at the quantum level. Professor Pate's research aims to bridge this gap by specifically tailoring a novel extension of the holographic principle to this quantum gravitational scattering problem. Through this research, Professor Pate's endeavors will contribute to the national interest in attaining a precise technical understanding of the natural world. This work will critically evaluate the viability of holography as the new physical paradigm necessary for describing quantum gravity, while also providing valuable insight into more basic questions including those regarding the identity of the fundamental building blocks of the universe. While the content of Professor Pate's research is selected based on intellectual merit, the strategic choice of problem-driven as opposed to methods-based projects is well-suited for easing the entry of new talent into a technically formidable field. The mentorship provided during the course of these projects will contribute to the development of new scientific leaders as well as to a sustained growth towards the full participation of women and members of other underrepresented groups in the field of high energy theory. As such, these efforts form part of the broader endeavor to create an equitable and diverse scientific community. At a more technical level, Professor Pate's research aims to constrain and determine scattering amplitudes in quantum gravity. Analyses will entail an extension of the holographic principle from the well-studied context of asymptotically Anti-de Sitter spacetimes to asymptotically flat spacetimes, which are the most natural setting for the gravitational scattering problem. More specifically, aspects of the celestial holographic proposal, which posits an equivalence between gravitational scattering and a theory with conformal symmetry on the celestial sphere, will be investigated. A primary objective is to develop and assess the viability of celestial holography in the context of quantum gravitational systems that resemble the real world. A specific goal is to extend many of the novel symmetries and similar organizing principles underlying recent progress in celestial holography to massive scattering particles. Another focus will be to develop a coherent picture of boundary and bulk renormalization in celestial holography. Methods will include a synthesis of top-down and bottom-up approaches. An auxiliary objective is to uncover new phenomena within the known laws of physics. The discovery and exploitation of recently-discovered symmetries of asymptotically flat spacetimes is the main approach that will be employed to make progress along this front. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.