PhD (Harvard, 2008)
Suvrat Raju's research focuses on quantum gravity and quantum field theory.
Quantum gravity has brought modern physics to an unusual position. Although in most physical problems it is possible to find several theories that are internally consistent, only one of them is externally consistent i.e. describes how nature works. However, putting together the general theory of relativity, which describes classical gravity, and quantum mechanics creates so many puzzles and paradoxes that it is hard to find even one internally consistent theory.
The first problem is that quantum gravity predicts the existence of "gravitons" which are particles associated with gravity-waves, just like photons are associated with light-waves. But, naively, the amplitude for two of these gravitons to scatter off each other grows too fast to be consistent with quantum mechanics. This problem was solved by the advent of perturbative string theory.
However, the introduction of black holes creates further puzzles. Black-holes are regions of spacetime, from which even light cannot escape. Can we say anything about the nature of this region of space?
Moreover, it is known that, quantum mechanically, black holes evaporate. Quantum mechanics also tells us that this process should be reversible but, naively, as the black hole evaporates it loses memory about its initial state.
The AdS/CFT correspondence provides us with a framework within which we can address many of these puzzles. Much of Prof. Raju's work has focused on this correspondence. He is also interested in the possibility of new formulations of quantum field theory.
1. Alok Laddha, Siddharth G. Prabhu, Suvrat Raju, Pushkal Shrivastava, "The Holographic Nature of Null Infinity", e-print: arXiv:2002.02448 [hep-th].
2. Kyriakos Papadodimas, Suvrat Raju, Pushkal Shrivastava, "A simple quantum test for smooth horizons", e-print: arXiv:1910.02992 [hep-th].
3. Suvrat Raju, "Is Holography Implicit in Canonical Gravity?", e-print: arXiv:1903.11073 [hep-th].
4. Souvik Banerjee, Kyriakos Papadodimas, Suvrat Raju, Prasant Samantray, Pushkal Shrivastava, "A Bound on Thermal Relativistic Correlators at Large Spacelike Momenta", e-print: arXiv:1902.07203 [hep-th].
5. Suvrat Raju, "A Toy Model of the Information Paradox in Empty Space", SciPost Phys. 6, 073 (2019), e-print: arXiv:1809.10154 [hep-th].
6. Suvrat Raju, Pushkal Shrivastava, "A Critique of the Fuzzball Program", Phys. Rev. D 99, 066009 (2019), e-print: arXiv:1804.10616 [hep-th].