# Physics Events

• Monday, November 12, 2018
High Energy Theory Seminar
“Energy is Entanglement”

Location: Bloomberg Lecture Hall
Time: 2:30 PM
Speaker(s): Arvin Shahbazi Moghaddam, University of California, Berkeley

Description: We compute the local second variation of the von Neumann entropy of a region in theories with a gravity dual. For null variations our formula says that the diagonal part of the Quantum Null Energy Condition is saturated in every state, thus providing an equivalence between energy and entropy. We conjecture that the QNEC is saturated in all interacting theories and discuss aspects of the proof of this statement in general interacting CFTs. We also discuss the special case of free theories, and the implications of our formula for the Averaged Null Energy Condition, Quantum Focusing Conjecture, and gravitational equations of motion.

• Tuesday, November 13, 2018
Pheno & Vino Seminar
“Conformal Field Theory, Hamiltonian Truncation, and You”

Location: Jadwin Hall, Room 303
Time: 4:00 PM
Speaker(s): Liam Fitzpatrick, Boston University

Description: Conformal Field Theories (CFTs) have a highly constrained structure that make them much more tractable, especially at strong coupling, than generic QFTs.  An appealing picture for more general QFTs is as points along the RG flow from a UV CFT.  We discuss conformal truncation as a method for nonperturbatively following such RG flows.  We describe some examples of past and potential applications, and in particular some of the advantages of the method for studying gauge theories, as well as remaining challenges.

• Wednesday, November 14, 2018
Physics Group Meeting
“Nonsupersymmetric D-branes”

Location: Bloomberg Hall Physics Library
Time: 1:45 PM
Speaker(s): Edward Witten, Faculty, School of Natural Sciences, IAS

Description: These were originally discovered by Sen (see hep-th/9808141, hep-th/9809111, hep-th/9904207, for example).   Another interesting paper is by Kraus and Larsen, hep-th/0012198.
I will describe a new perspective based on anomalies.

• Thursday, November 15, 2018
Special Condensed Matter Seminar
“Exact Strong-ETH Violating Eigenstates in the Rydberg-blockaded Atom Chain”

Location: PCTS Seminar Room 407
Time: 2:15 PM
Speaker(s): Cheng Ju Lin, Caltech

Description: A recent experiment in the Rydberg atom chain observed unusual oscillatory quench dynamics with a charge density wave initial state, and theoretical works identified a set of many-body scar states'' in the Hamiltonian as potentially responsible for the atypical dynamics. In the same nonintegrable Hamiltonian, we discover several eigenstates at infinite temperature that can be represented exactly as matrix product states with finite bond dimension, for both periodic boundary conditions (two exact E = 0 states) and open boundary conditions (two E = 0 states and one each E = 2). This discovery explicitly demonstrates violation of strong eigenstate thermalization hypothesis in this model. These states show signatures of translational symmetry breaking with period-2 bond-centered pattern, despite being in 1D at infinite temperature. We show that the nearby many-body scar states with energies E ~ 1.33 andE ~ 2.66 can be well approximated as quasiparticle excitations" on top of our exact E = 0 states, and propose a quasiparticle explanation of the strong oscillations observed in experiments.

• Thursday, November 15, 2018
Princeton University Department of Physics Donald R. Hamilton Colloquium Series
“Wonders of Viscous Electronics”

Location: Jadwin Hall, Room A10
Time: 4:00 PM
Speaker(s): Gregory Falkovich, Weizmann Institute of Science

Description: 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. Such flows have some remarkable properties never seen before. I shall describe recent theoretical and experimental works devoted, in particular, to a striking macroscopic DC transport behavior: viscous friction can drive electric current against an applied field, resulting in a negative resistance, recently measured experimentally in graphene. I shall also describe conductance exceeding the fundamental quantum-ballistic limit, field-theoretical anomalies and other wonders of viscous electronics. Strongly interacting electron-hole plasma in high-mobility graphene affords a unique link between quantum-critical electron transport and the wealth of fluid mechanics phenomena.
https://phy.princeton.edu/events/donald-r-hamilton-colloquium-series

• Friday, November 16, 2018
High Energy Theory Seminar
“M-theory in 4D, N=1 Superspace”

Location: Bloomberg Lecture Hall
Time: 1:45 PM
Speaker(s): Katrin Becker, Member, School of Natural Sciences / Texas A&M University

Description: I report on progress in formulating eleven-dimensional supergravity in a framework in which four supersymmetries are manifest.

• Monday, November 19, 2018
High Energy Theory Seminar
“Boundary Dual of the Bulk Symplectic Form and the Volume of Maximal Slices”

Location: Jadwin Hall, PCTS Seminar Room, 4th Floor
Time: 2:30 PM
Speaker(s): Gabor Sarosi, University of Pennsylvania & University of Brussels

Description: In this talk, I will explain how to understand the symplectic structure of the gravitational phase space in AdS in terms of the quantum overlap in the holographically dual CFT. As an application, I will use this to study the boundary description of the volume of maximal Cauchy slices. I will construct the boundary deformation that is conjugate to the volume in empty AdS, and the thermofield double at infinite time. I will explain the bulk interpretation of this deformation and speculate on its boundary interpretation. This will motivate a concrete version of the complexity equals volume conjecture, where the boundary complexity is defined as the energy of geodesics in a Kahler geometry of half sided Euclidean sources. I will calculate this complexity for states dual to Banados geometries that are close to the vacuum, and discuss a mini superspace approximation in the case of the time dependent thermofield double.

• Wednesday, November 21, 2018
Physics Group Meeting
“TBA”

Location: Bloomberg Hall Physics Library
Time: 1:45 PM
Speaker(s): Tom Rudelius, Member, School of Natural Sciences, IAS

• Monday, November 26, 2018
High Energy Theory Seminar
“Stringy ER=EPR”

Location: Bloomberg Lecture Hall
Time: 2:30 PM
Speaker(s): Daniel Jafferis, Harvard University

Description:

• Tuesday, November 27, 2018
Pheno & Vino Seminar
“From the Table-Top to the Cosmos: Searching High and Low for Dark Matter”

Location: Jadwin Hall, Room 303
Time: 4:00 PM
Speaker(s): Hongwan Liu, MIT

Description: In this talk, I will explore two recent developments in the search for dark matter. First, I will discuss how the 21-cm global signal measurement constrains the potential impact of dark matter annihilation/decay on the thermal history of the universe. I will also explain how to accurately compute such modifications to the baryon temperature in the early universe using a soon-to-be-released public code called DarkHistory. Second, I will discuss the Axion Detection with Birefringent Cavities (ADBC) experiment, which aims to observe rotations induced by axion dark matter in the polarization of light using optical interferometry techniques.

• Wednesday, November 28, 2018
Physics Group Meeting
“TBA”

Location: Bloomberg Hall Physics Library
Time: 1:45 PM
Speaker(s): Nima Arkani-Hamed, Faculty, School of Natural Sciences, IAS

• Thursday, November 29, 2018
Princeton University Department of Physics Donald R. Hamilton Colloquium Series
“The Chiral Anomaly in Dirac Semimetals”

Location: Jadwin Hall, Room A10
Time: 4:00 PM
Speaker(s): Nai Phuan Ong, Princeton University

Description: I will talk about recent experiments on the chiral anomaly in Dirac semimetals. In field theory, Dirac fermions of zero mass must segregate into left- and right-handed populations that do not ever mix. In this limit, chiral symmetry (handedness) is a global symmetry of the Lagrangian. However, quantum effects induced by coupling to a vector gauge field kill the symmetry. This is known as the chiral (or axial) anomaly. The first example appeared (1968) in the decay of neutral pions into 2 photons (the Adler-Bell-Jackiw anomaly). Since then, anomalies have been implicated in many important problems, e.g. the $U(1)_A$ problem, renormalizability of the electroweak theory, and the fermion-doubling problem in lattice QCD. It is also directly related to the Atiyah-Singer index theorem. In 1983, Nielsen and Ninomiya predicted that the chiral anomaly should be observable as well in bulk semimetals that feature protected 3D Dirac cones. Breaking of time-reversal invariance in a magnetic field B converts the Dirac electrons in a semimetal to Weyl fermions. The chiral nature of the Weyl fermions become manifest in the lowest Landau level (in intense B). An electric field applied parallel to B shifts the left and right-moving branches to produce an axial current. I will describe experiments on $Na_3Bi$ and GdPtBi which show the dramatic emergence of the anomaly, and focus on issues peculiar to the anomaly in crystals. I will describe a litmus test that sharply distinguishes this quantum effect from (classical) artifacts caused by current jetting.
https://phy.princeton.edu/events/donald-r-hamilton-colloquium-series

• Friday, November 30, 2018
High Energy Theory Seminar
“TBA”

Location: Bloomberg Lecture Hall
Time: 1:45 PM
Speaker(s): Anna Karlsson, Member, School of Natural Sciences, IAS

Description:

• Monday, December 3, 2018
PCTS Workshop
“Fracton Phases of Matter and Topologial Crystalline Order”

Location: Jadwin Hall, PCTS Seminar Room
Time: 8:30 AM
Speaker(s): http://www.physics.princeton.edu/pcts/Fracton2018/posterFracton.pdf
Note: Registration is now open!

Description: Program Organizers: Fiona Burnell, Biao Lian, Abhinav Prem, Shivaji Sondhi, and Yizhi You
Topological quantum phases of matter remain one of the most exciting playgrounds for exploring the interplay between strong correlations, symmetry, and topology in many-body quantum systems. Recently, there has been growing interest in novel quantum phases of matterso-called fracton phases. These systems extend and challenge our existing notions of topological order and have attracted broad interdisciplinary interest, lying at the intersection of multiple fields including topological order, higher rank gauge theories, gravity, quantum information, and elastic descriptions of soft matter. We expect that this workshop will bring together leading experts from these various communities, with the primary aim being the stimulation of discussions and promotion of cross-disciplinary interactions amongst the participants.

http://www.physics.princeton.edu/pcts/Fracton2018/fracton2018.html

• Tuesday, December 4, 2018
Qubit Workshop
“Quantum Information and the Structure of Spacetime”

Location: Wolfensohn Hall
Time: 8:00 AM

Description: Please Note: This workshop is not open to the general public, but only to active researchers.

This workshop will focus on quantum aspects of black holes, focusing on applying ideas from quantum information theory.

This meeting is sponsored by the It from Qubit collaboration and is followed by the collaboration meeting in New York City.

Wednesday, November 28, 2018
All participants must register. https://www.sns.ias.edu/quantum-information-workshop-2018/registration
https://www.sns.ias.edu/quantum-information-workshop-2018

• Tuesday, December 4, 2018
PCTS Workshop
“Fracton Phases of Matter and Topologial Crystalline Order”

Location: Jadwin Hall, PCTS Seminar Room
Time: 8:30 AM
Speaker(s): http://www.physics.princeton.edu/pcts/Fracton2018/posterFracton.pdf
Note: Registration is now open!

Description: Program Organizers: Fiona Burnell, Biao Lian, Abhinav Prem, Shivaji Sondhi, and Yizhi You
Topological quantum phases of matter remain one of the most exciting playgrounds for exploring the interplay between strong correlations, symmetry, and topology in many-body quantum systems. Recently, there has been growing interest in novel quantum phases of matterso-called fracton phases. These systems extend and challenge our existing notions of topological order and have attracted broad interdisciplinary interest, lying at the intersection of multiple fields including topological order, higher rank gauge theories, gravity, quantum information, and elastic descriptions of soft matter. We expect that this workshop will bring together leading experts from these various communities, with the primary aim being the stimulation of discussions and promotion of cross-disciplinary interactions amongst the participants.

http://www.physics.princeton.edu/pcts/Fracton2018/fracton2018.html

• Wednesday, December 5, 2018
Qubit Workshop
“Quantum Information and the Structure of Spacetime”

Location: Wolfensohn Hall (Bloomberg Hall 4:00 - 6:00 pm)
Time: 8:00 AM

Description: Please Note: This workshop is not open to the general public, but only to active researchers.

This workshop will focus on quantum aspects of black holes, focusing on applying ideas from quantum information theory.

This meeting is sponsored by the It from Qubit collaboration and is followed by the collaboration meeting in New York City.

Wednesday, November 28, 2018
All participants must register. https://www.sns.ias.edu/quantum-information-workshop-2018/registration
https://www.sns.ias.edu/quantum-information-workshop-2018

• Wednesday, December 5, 2018
PCTS Workshop
“Fracton Phases of Matter and Topologial Crystalline Order”

Location: Jadwin Hall, PCTS Seminar Room
Time: 8:30 AM
Speaker(s): http://www.physics.princeton.edu/pcts/Fracton2018/posterFracton.pdf
Note: Registration is now open!

Description: Program Organizers: Fiona Burnell, Biao Lian, Abhinav Prem, Shivaji Sondhi, and Yizhi You
Topological quantum phases of matter remain one of the most exciting playgrounds for exploring the interplay between strong correlations, symmetry, and topology in many-body quantum systems. Recently, there has been growing interest in novel quantum phases of matterso-called fracton phases. These systems extend and challenge our existing notions of topological order and have attracted broad interdisciplinary interest, lying at the intersection of multiple fields including topological order, higher rank gauge theories, gravity, quantum information, and elastic descriptions of soft matter. We expect that this workshop will bring together leading experts from these various communities, with the primary aim being the stimulation of discussions and promotion of cross-disciplinary interactions amongst the participants.

http://www.physics.princeton.edu/pcts/Fracton2018/fracton2018.html

• Friday, December 7, 2018
High Energy Theory Seminar
“TBA”

Time: 1:45 PM
Speaker(s): TBA, TBA

• Monday, December 10, 2018
High Energy Theory Seminar
“TBA”

Location: Bloomberg Lecture Hall
Time: 2:30 PM
Speaker(s): Erich Poppitz, University of Toronto

• Friday, December 14, 2018
High Energy Theory Seminar
“TBA”

Location: Bloomberg Lecture Hall
Time: 1:45 PM
Speaker(s): TBA, TBA

• Monday, January 14, 2019
PCTS Workshop
“Novel Ideas for Dark Matter”

Location: Jadwin Hall, Fourth Floor, Room 407, PCTS Seminar Room
Time: 8:30 AM
Note: Register here: https://docs.google.com/forms/d/e/1FAIpQLSf30X77lY09RVrDcsx98KJJkRoy3akoR5TCQESS101MoT2Y5g/viewform

Description: Dark matter research is undergoing a paradigm shift. Over the last few years, many novel theories have been proposed that challenge the standard assumptions made about dark matter. At the same time, new observations and simulation results are providing valuable clues regarding the most fruitful directions moving forward.

The “Novel Ideas for Dark Matter 2019” workshop at Princeton University attempts to bridge the gap between communities working on non-standard solutions to the dark matter problem. Plenary talks on theory, observations and simulations will be structured into a three day schedule that will provide a broad overview of research avenues of this type. The workshop aims to promote conversations between research communities with ample time for open discussion.

Organizing committee:
Oren Slone - oslone@princeton.edu
Mariangela Lisanti - mlistanti@princeton.edu
Tomer Volansky - tomerv@post.tau.ac.il
http://pcts.princeton.edu/pcts/current_future_programs.html

• Tuesday, January 15, 2019
PCTS Workshop
“Novel Ideas for Dark Matter”

Location: Jadwin Hall, Fourth Floor, Room 407, PCTS Seminar Room
Time: 8:30 AM
Note: Register here: https://docs.google.com/forms/d/e/1FAIpQLSf30X77lY09RVrDcsx98KJJkRoy3akoR5TCQESS101MoT2Y5g/viewform

Description: Dark matter research is undergoing a paradigm shift. Over the last few years, many novel theories have been proposed that challenge the standard assumptions made about dark matter. At the same time, new observations and simulation results are providing valuable clues regarding the most fruitful directions moving forward.

The “Novel Ideas for Dark Matter 2019” workshop at Princeton University attempts to bridge the gap between communities working on non-standard solutions to the dark matter problem. Plenary talks on theory, observations and simulations will be structured into a three day schedule that will provide a broad overview of research avenues of this type. The workshop aims to promote conversations between research communities with ample time for open discussion.

Organizing committee:
Oren Slone - oslone@princeton.edu
Mariangela Lisanti - mlistanti@princeton.edu
Tomer Volansky - tomerv@post.tau.ac.il
http://pcts.princeton.edu/pcts/current_future_programs.html

• Tuesday, January 15, 2019
PCTS Workshop
“Novel Ideas for Dark Matter”

Location: Jadwin Hall, Fourth Floor, Room 407, PCTS Seminar Room
Time: 8:30 AM
Note: Register here: https://docs.google.com/forms/d/e/1FAIpQLSf30X77lY09RVrDcsx98KJJkRoy3akoR5TCQESS101MoT2Y5g/viewform

Description: Dark matter research is undergoing a paradigm shift. Over the last few years, many novel theories have been proposed that challenge the standard assumptions made about dark matter. At the same time, new observations and simulation results are providing valuable clues regarding the most fruitful directions moving forward.

The “Novel Ideas for Dark Matter 2019” workshop at Princeton University attempts to bridge the gap between communities working on non-standard solutions to the dark matter problem. Plenary talks on theory, observations and simulations will be structured into a three day schedule that will provide a broad overview of research avenues of this type. The workshop aims to promote conversations between research communities with ample time for open discussion.

Organizing committee:
Oren Slone - oslone@princeton.edu
Mariangela Lisanti - mlistanti@princeton.edu
Tomer Volansky - tomerv@post.tau.ac.il
http://pcts.princeton.edu/pcts/current_future_programs.html