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Time: 2pm 
Location: 2N36
Title: TBA

Time: 2pm
Location: 2N36
Title: TBA

Time: 2pm 
Location: 2N36
Title: TBA

Time: 2pm
Location: 2N36
Title: Shaving off Black Hole Soft Hair
Abstract: After recalling a definition of a black hole "hair" we explain why the only interesting hairs are those that are also remnants. Next, we will examine a recent proposal by Hawking, Perry and Strominger, who suggest that soft photons and soft gravitons can be regarded as black hole hairs that may be relevant to the black hole information paradox. We will make use of factorization theorems for infrared divergences of the S-matrix to argue that, by appropriately dressing in and out hard states, the soft-quanta-dependent part of the S-matrix becomes essentially trivial, in the sense that the information paradox can be fully formulated in terms of dressed hard states, which do not depend on soft quanta.

Time: 2pm
Location: 2N36
 
Title: Reinventing the wheel: an effective theory approach to dissipative spinning objects.
 
 Abstract: In this talk, I will show how effective field theory techniques can be used to shed a new light on the dissipative dynamics of spinning astrophysical objects. After introducing the basic formalism, I will discuss two different applications. The first one is a modern description of superradiance — a phenomenon by which a spinning object can loose angular momentum by amplifying the intensity of scattered radiation, or by producing particles in a bound state. Along the way, I will also provide a simple derivation of vacuum friction — a “quantum torque” that acts on spinning objects in empty space. The second application I will discuss (if time will allow it) is to tides and the role they play in the dynamics of moons, planets and other “Newtonian” objects. I will argue in particular that the time scales over which orbit circularization and tidal locking take place satisfy a hierarchy which follows exclusively from symmetry and is thus a model independent prediction of the effective theory.

Time: 2pm
Location: 2N36
Title: TBA 

Time: 2pm
Location: 2N36
 
Title: Relative entropy of excited states in conformal field theories

Abstract:We study the relative entropy between the reduced density matrices obtained from globally excited states in conformal field theories of arbitrary dimensions. We find a general formula in the small subsystem size limit.  When one of the states is the vacuum of the CFT, our result matches with the holographic entanglement entropy computations in the corresponding bulk geometries, including AdS black branes. We also discuss the first asymmetric part of the relative entropy and comment on some implications of the results on the distinguishability of black hole microstates in AdS/CFT.

Time: 2pm 
Location: 2N36
Title: Recent developments in 3-D dualities

Abstract: This summer has seen a flurry of activity in particle-vortex duality and, more generally, in non-supersymmetric dualities in three spacetime dimensions. Much of this work has been directly related to the properties of so-called topological quantum matter and gapped phases of matter. In this talk, I will give a more-or-less pedagogical introduction to these ideas, beginning with the sine-Gordon/massive Thirring correspondence and building toward our current understanding of the 3-dimensional web of dualities.

Time: 2pm
Location: 2N36

Title: No-go results and promising directions in the space of causal diamonds
Abstract: The space of causal diamonds recently brought to attention by de Boer et al. and Czech et al. provides an organizing principle for the dependence of entanglement entropy in conformal field theories on the spatial subregion considered. I will show that the inclusion relation of causal diamonds does not give rise to a consistent notion of a causal structure and thus does not provide an alternate metric on this space. I will also show that the entanglement entropy of ball shaped regions is not enough to reconstruct the areas of higher dimensional bulk surfaces in a static geometry. Instead, I will provide a new direction for the reconstruction of the areas of bulk surfaces from boundary data in holography, using the shape derivatives of the entanglement entropy of nearly ball shaped regions.

Time: 2pm
Location: 2N36
Title: New forms of quantum entanglement in discretely gauged theories

Time: 2pm
Location: 2N36
Title: Entanglement growth in quantum quenches

Abstract: A global quench is an interesting setting where we can study thermalization of subsystems in a pure state. We investigate the spread of entanglement following a global quench in free field theory, holography, spin chains, and toy models. We find that the results in free scalar field theory are exactly reproduced by the model of free streaming quasiparticles, but strongly interacting chaotic systems spread entanglement more effectively. Based on recent insight into many-body quantum chaos, we propose two inequalities on the entropy, and suggest that the true evolution of the entropy is well approximated by saturating the combined bounds. A model based on the chaotic growth of operators saturates the combined bounds, and is a promising candidate to replace the quasiparticle model for chaotic systems.

Time: 2pm
Location: 2N36
 
Title: AdS_2 holography and non-extremal black holes

Abstract: I will present aspects of AdS_2 holography for a specific Einstein-Maxwell-Dilaton model that is obtained by Kaluza-Klein reduction from pure AdS_3 gravity with negative cosmological constant. In particular, I will derive the one-dimensional holographic dual for both running and constant dilaton solutions, and I will discuss the connection with the Sachdev-Ye-Kitaev model. Finally, I will explain how this dilaton gravity model provides a holographic description for four-dimensional asymptotically conformally AdS_2 x S^2 non-extremal black holes.   The talk is based on the recent paper https://arxiv.org/abs/1608.07018.

Time: 2pm
Location: 2N36
Title: Entanglement, Holography and Causal Diamonds

Time: 2pm
Place: 2N36
 
Title: Tunneling in Quantum Field Theory and the Fate of the Universe
 
Abstract:
One of the most concrete implications of the discovery of the Higgs
boson is that, in the absence of physics beyond the standard model, the
long term fate of our universe can now be established through precision
calculations. Are we in a metastable minimum of the Higgs potential or
the true minimum? If we are in a metastable vacuum, what is its
lifetime? To answer these questions, we need to understand tunneling in
quantum field theory. As we delve into how tunneling works, we find many
unusual elements: complex quantities which should be real,
gauge-dependent quantities which should be physical, an hbar expansion
which differs from the ordinary loop expansion, and ultraviolet degrees
of freedom that don't decouple. This talk will discuss some of these
elements and present some new perspectives on quantum tunneling.

Time: 2pm
Place: 2N36
 
 
Title: "Bad Compactifications"

Abstract:

The parameter space of string compactifications contains a locus of
"bad" theories. These theories are physically the most interesting in
many ways. We analyze the bad locus of theories at various levels ---
where it is, it's multiplicity, and finally, we "categorify" it.
This is all done in the context of abelian gauged linear sigma models.

Time: 2pm
Place: 2N36
 
Title: Scrambling of locally perturbed thermal states
 
Abstract:
I will discuss the calculation of mutual information in 2d CFTs in the large c limit to determine the scrambling time scale at which it becomes small. Time permitting, I will make some remarks on the comparison between this approach and the calculation of out of time order correlators at finite temperature.

Place: DRL 4N12  
Thursday, April 7:

10:30-11am: Welcome coffee

11am -12:30pm: Rob Myers (Perimeter)
Title: Scanning New Horizons: Information, Holography & Gravity

12:30pm-2pm: Catered lunch (in 4N12)

2-3:30pm: Matt Headrick (Brandeis)
Title: A new perspective on holographic entanglement

3:30-4pm: Coffee

4-5:30pm: Daniel Roberts (MIT)
Title: Chaos in quantum channels

6:30pm: Conference dinner at Han Dynasty

Friday, April 8:

10:30-11am: Welcome coffee

11am -12:30pm: Herman Verlinde (Princeton)
Title: 

12:30pm-1pm: Catered lunch (in 4N12)

1-2:30pm: Jan de Boer (Amsterdam) 
Title: Entanglement Holography

3:30-4pm: Coffee

4-5:30pm:  Bartek Czech (Stanford)
Title: A stereoscopic look into the bulk

End of the workshop

Time: 3:30pm
Place: 4N12
 
Title: Strings, Exotics, and the 750 GeV Diphoton Excess
 
Abstract:

I first give a general review of the experimental, phenomenological, and theoretical status of
the possible diphoton excess at 750 GeV reported by  CMS and ATLAS. I then describe work done in collaboration with Mirjam Cvetic and Jim Halverson (hep-ph/1512.07622 and 1602.06257) attempting to explain the excess in terms of the types of  scalar particles and exotic vectorlike particles expected in a class of superstring constructions, taking into account experimental limits, expected Yukawa couplings, and perturbativity up to a large string scale.

 
 

Time: 2pm
Place: 2N36
 
Title: Effective field theory of dissipative fluids