====== TF01: String theory, quantum gravity, black holes ======
Co-Conveners: Daniel Harlow (MIT), Shamit Kachru (Stanford), Juan Maldacena (IAS)

===== Description=====
Understanding how gravity and quantum mechanics are combined to give a description of spacetime in a full quantum mechanical fashion is one of the most important problems in physics.  Solving this problem is necessary to obtain a satisfactory picture of the early history of the universe, as well a complete picture of the physics of black holes.  Such an understanding may also contribute to a unified model of fundamental interactions, and shed light on issues such the hierarchy and cosmological constant problems.

A widely studied approach to quantum gravity is string theory, which is a modification of Einstein gravity that produces a well defined perturbation series. In addition, it can potentially incorporate the other interactions, described by the Standard Model, into a self consistent framework. There are special corners of string theory, such as those provided by the AdS/CFT correspondence, where a complete non-perturbative picture is available. These corners do not have realistic physics, but they provide important “existence proofs” of the feasibility of combining quantum mechanics and gravity. Studying them in detail has led to many new insights about quantum gravity, in particular into the quantum properties of black holes and the emergence of spacetime.

In addition to its role as a potential theory of quantum gravity, string theory has also turned out to be a remarkable source of ideas for many related branches of physics and mathematics. These include particle physics model building, cosmology, quantum chromodynamics,  many-body quantum systems, quantum chaos, classical gravity, quantum information theory, geometry, and number theory. For this reason string theory has become an essential part of modern theoretical physics. 

Subtopics to be explored:

  * Quantum aspects of black holes and the emergence of spacetime
  * New ideas for many-body quantum systems from string theory and black holes
  * String theory and particle physics: compactification and unification
  * String theory and early universe: conceptual and phenomenological questions
  * New ideas in classical gravity from quantum fields and strings
  * New discoveries in mathematics from string theory and quantum field theory

===== Submitted LOI =====
Here is the list of submitted LOIs to this  topic. 
 First index before "/"  corresponds to the primary frontier used for the submission.
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