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Post-doctoral Research fellow

University of British Columbia

Department of Physics & Astronomy

pbetzios@phas.ubc.ca

Welcome to My Website

I am currently carrying out post-doctoral research at the department of Physics & Astronomy at the University of British Columbia. My research interests are revolving around the general theme of Gauge/Gravity dualities, Matrix models and the emergence of spacetime. I am also trying to understand the physics of black holes and wormholes using string-theoretic and other mathematical tools such as those of random matrices.

Gauge/Gravity Duality

Gauge/Gravity duality is a very broad subject that many scientists are trying to develop. It relates non-gravitating quantum field theories (QFT's) with string theory -or its low energy gravitational spin-offs for all practical purposes- in higher dimensions. During the historical evolution of theoretical physics there were numerous hints pointing towards it.

First, the study of the large N limit of gauge theories by Gerard 't Hooft revealed that they admit a string-like expansion. Moreover correlators of gauge invariant operators factorize up to 1/N corrections, a fact that hints to a classical description at first order in 1/N that people were not able to fully exploit (exept in special cases of low dimensionality such as random matrices/ matrix quantum mechanics). Another hint was the open/closed duality in string theory that relates tree level closed string propagation with one loop open string amplitudes.

In parallel, the main conceptual idea -Holography- was already intuitively developed from Gerard 't Hooft and Leonard Susskind in the early 90's. It was based on the studies of black holes and in particular on the remark that the entropy of a black hole obeys an area law and not a volume law as local quantum field theories do -gravity in a sense has much less degrees of freedom than usual quantum field theories in the same number of dimensions-.

These ideas culminated in the work of Juan Maldacena who managed to establish a quantitative connection in the case of spacetimes having AdS (Anti-DeSitter) asymptotics. From then a flurry of activity developed these ideas of holography and emergent space much further both from a phenomenological as well as a mathematical and fundamental perspective, even outside the realm of asymptotically AdS spaces.