Quantum Fields and Strings
This series consists of talks in the area of Quantum Fields and Strings.
Seminar Series Events/Videos
-
Tuesday Dec 12, 2017Speaker(s):
Many researchers have been studying the time evolution of entanglement entropy in the sudden quenches where a characteristic mass scale suddenly changes. It is well-know that in these quenches, the change of entanglement entropy become thermal entropy which is proportional to a subsystem size in the late time. However, we do not know which quenches thermalize a subsystem. In our works, we have been studied the time evolution of quantum entanglement in the global quenches with finite quench rate (smooth quenches).
Collection/Series:Scientific Areas:
-
Tuesday Dec 05, 2017Speaker(s):
Abstract TBA
Collection/Series:Scientific Areas:
-
Tuesday Nov 28, 2017Speaker(s):
Gravitational shockwaves may signal the breakdown of effective field theory near black hole horizons. Motivated by this, I will revisit the Dray-‘t Hooft solution and explain how to generalize it to the Kerr-Newman background. In doing so I will emphasize the method of spin coefficients (the Newman-Penrose formalism) in its compacted form (the Geroch-Held-Penrose formalism).
Collection/Series:Scientific Areas:
-
Tuesday Nov 21, 2017Speaker(s):
In this talk I prove that the standard notion of entanglement is not defined for gravitationally anomalous two-dimensional theories because they do not admit a local tensor factorization of the Hilbert space into local Hilbert spaces. I make this precise by combining two observations:
First, a two-dimensional CFT admits a consistent quantization on a space with boundary only if it is not anomalous.
Second, a local tensor factorization always leads to a definition of consistent, unitary, energy-preserving boundary condition.Collection/Series:Scientific Areas:
-
Thursday Nov 16, 2017Speaker(s):
Quantum-critical strongly correlated systems feature universal collision-dominated collective transport. Viscous electronics is an emerging field dealing with systems in which strongly interacting electrons flow like a fluid. I shall describe recent theoretical and experimental results: negative resistance, current vortices, expulsion of electric field, conductance exceeding the fundamental quantum-ballistic limit and other wonders of viscous electronics.
Nature Physics 2016, 2017, PNAS 2017, PhysRevLet 2017
Collection/Series:Scientific Areas:
-
Tuesday Nov 14, 2017Speaker(s):
Carefully studying the singularity structure of the moduli space of vacua of super conformal field theories, provides an incredibly powerful tool to extract information about such theories. In particular I will outline a concrete, yet technically challenging, strategy to go about carrying out a classification for SCFTs with extended supersymmetry in 4d.
Collection/Series:Scientific Areas:
-
Tuesday Nov 07, 2017Speaker(s):
We establish a direct connection between scattering amplitudes for bi-adjoint scalar theories and a classic polytope--the "associahedron"--known to mathematicians since the 1960s. We find an associahedron naturally living in kinematic space. The tree level scattering amplitude is simply a geometric invariant of the associahedron called its "canonical form" [2], which is a differential form on kinematic space with logarithmic singularities on the boundaries of the associahedron.
Collection/Series:Scientific Areas:
-
Monday Oct 30, 2017Speaker(s):
I will describe a holographic solution corresponding to a traversable wormhole in AdS/CFT. The construction involves directly coupling the boundary CFT's, and corresponds to chaos-facilitated quantum teleportation between the two sides. It does not violate boundary causality or other fundamental physics principles.
Collection/Series:Scientific Areas:
-
Tuesday Oct 24, 2017Speaker(s):
Known N=4 theories in four dimensions are characterized by a choice of gauge group, and in some cases some "discrete theta angles", as classified by Aharony, Seiberg and Tachikawa. I will review how this data, for the theories with algebra su(N), is encoded in various familiar realizations of the theory, in particular in the holographic AdS_5 \times S^5 dual and in the compactification of the (2,0) A_N theory on T^2.
Collection/Series:Scientific Areas:
-
Tuesday Oct 17, 2017Speaker(s):
I discuss some aspects of boundary conformal field theories (bCFTs). I will demonstrate that free bCFTs have a universal way of satisfying crossing symmetry constraints. I will introduce a simple class of interacting bCFTs where the interaction is restricted to the boundary. Finally, I will discuss relationships between boundary trace anomalies and boundary limits of stress-tensor correlation functions.
Collection/Series:Scientific Areas:
Pages
LECTURES ON-DEMAND
