* denotes the organizer responsible for participant diversity

May 28 – September 17
Individual Research

Physicists are encouraged to apply as individual researchers to work on their own projects at the Aspen Center for Physics for up to five weeks at any time during the summer. We provide a serene atmosphere to complete work. The individual researcher may also choose to attend any workshop meetings or chat with other scientists in residence in addition to working on his or her own research. Click here for more information.

May 28 – September 17
Working Group

Working groups of between two and six physicists are encouraged. Click here for more information.

May 28 - June 18
After Inflation

Peter Adshead, University of Illinois
Mustafa Amin, Rice University
Scott Watson*, Syracuse University

There is a gap in our understanding of the period between the end of inflation and the production of the light elements. While the inflationary paradigm provides a consistent, calculable framework for understanding the origin of structure in our universe, we do not understand the details of how inflation ends and how we arrive at a universe with thermalized SM (and beyond SM) components. The detailed mechanisms for generating stable relics, such as dark matter, or generating the observed matter/antimatter asymmetry continue to elude us. The aim of the proposed workshop is to bring together experts in inflation and reheating, non-perturbative field dynamics and high energy particle physics phenomenology, as well as observers interested in exploring and constraining this rich period in our cosmic history.

May 28 - June 18
Quantum Gravity and New Moonshines

Alejandra Castro, University of Amsterdam
Miranda Cheng, University of Amsterdam
Anne Taormina, Durham University, UK
Katrin Wendland, Universitat Freiburg

In very recent years, the subject of Moonshine has made unexpected appearances in various corners of string theory, and most remarkably in the physics of black holes and lower dimensional gravity. This is leading to an avalanche of ``New Moonshine Conjectures'', which raises a multitude of open problems, and in our opinion the time is ripe to tackle them. Answers to these questions will deepen our understanding of conformal field theory, the string theory landscape, black holes and other aspects of quantum gravity.

This workshop is focused on these new developments in quantum gravity and its intricate connections with number theory, geometry and group theory. We believe that new approaches in both physics and mathematics can be developed by bringing together members of these seemingly unrelated communities.

June 4 - June 25
Information in Quantum Field Theory

Anatoly Dymarsky*, University of Kentucky
Daniel Harlow, Princeton University
Thomas Hartman , Cornell University
Sean Hartnoll, Stanford University

Quantum information theory is playing an increasingly important role in our understanding of fundamental properties of quantum field theory and quantum gravity. When combined with the local nature of interactions, information theory often leads to surprising and nontrivial results. The holographic correspondence further extends the reach of information theory to the realm of quantum gravity. This workshop will focus on applications of information theory to field theoretic systems, encompassing a wide range of topics fundamental to high energy theory, gravitational physics, and condensed matter. Among the areas of particular interest are:

+ Subregions in gauge theory and quantum gravity
+ Bounds on thermalization, transport, energy, and chaos in quantum field theories
+ Non-integrable conformal field theories in 1+1 dimensions

Our goal is to bring together a diverse community of researchers working in these and adjacent areas to foster a field-wide discussion of the role of information theory in quantum field theory.

June 11 - July 2
The Packing of Continua

Gregory Grason*, University of Massachusetts
Eleni Katifori, University of Pennsylvania
L. Mahadevan, Harvard University
Jennifer Schwarz, Syracuse University

Packing problems have been at the core physical descriptions of matter dating back to at least the time of Kepler. This workshop will bring together researchers from diverse fields working to understand packing of filaments and sheets in three-dimensional space. In comparison to problems of packing compact and rigid elements, the consequences of the more subtle interplay between shape and separation of continuously deformable, extended objects on their space-filling arrangements and collective behaviors at high density are far less understood. And this, despite the diverse applications of filament and sheet packing problems to current challenges in biology and materials science, from the fractal packing of condensed chromosomes to the design of 2D metamaterials. The scope of the workshop will cover recent advances in characterizing, understanding and optimizing multi-filament/sheet assemblies, as well as frontier questions stemming from new observations and emerging challenges in biological and synthetic matter.

June 18 - July 9
Neutron Stars: Linking Nuclear Physics of the Interior to Electromagnetic Observations and Gravitational Radiation

Gordon Baym*, University of Illinois
Tetsuo Hatsuda, RIKEN
Kostas Kokkotas, Tuebingen University
Feryal Ozel, University of Arizona

Neutron star physics is at a very fertile moment, with remarkable and ongoing progress from both observational and theoretical directions. The importance of understanding their behavior and structure has been underlined by the recent direct detection of gravitational radiation, since neutron stars mergers with black holes or neutron stars will be principal sources of future observations of gravitational waves. Direct observation of 2.0 solar mass stars and ongoing determinations of masses and radii are constraining the composition of neutron star interiors; the NICER experiment, soon to be delivered to the International Space Station, will provide a wealth of new data. At the same time, an emerging understanding in quantum chromodynamics (QCD) of how nuclear matter turns into deconfined quark matter at high baryon densities, has led to advances in understanding the equation of state of the matter under the extreme conditions in neutron star interiors, work complementary to studies of dense matter at ultrarelativistic heavy ion collision experiments at RHIC in Brookhaven and the LHC at CERN. The aim of this workshop is to bring together researchers from the various disciplines involved in these advances -- including observers of pulsars and compact X-ray sources, nuclear and QCD physicists studying dense matter, and gravitational wave physicists – to further advance understanding of neutron star interiors both microscopically and as constrained by observations.

June 25 - July 23
Correlations and Entanglement in and out of Equilibrium: From Cold Atoms to Electrons

Randall Hulet,Rice University
Meera Parish*, Monash University
David Pekker, University of Pittsburgh
Joerg Schmiedmayer, Vienna University of Technology

Remarkable developments of the last few years have changed how we understand and study quantum many-body systems, especially out of equilibrium. This progress is a result of work done in several different communities, including quantum field theory, cosmology, condensed matter physics, atomic physics, quantum information theory, and recently even string theory through the window of holography. The workshop aims to bring together leading theoretical and experimental experts from across different subfields of this endeavor with the aim to stimulate a stronger collaboration among groups that have quite different perspectives on the problem. The ultimate goal is to consolidate and deepen the understanding of new concepts in correlated quantum matter in- and out-of-equilibrium. The workshop will identify new research directions directed towards answering fundamental questions that previously eluded systematic treatment: (1) How do correlations build-up as one goes from the few- to the many-particle regime? (2) What are the basic mechanisms that govern thermalization in a closed quantum system, and what are their possible modes of failure? (3) What is the nature of the transition from a non-ergodic (e.g. many-body localized) quantum-state to an ergodic fluid? (4) What new phenomena emerge when we combine strong interactions with non-trivial topological band structures? (5) What new states of matter, with no equilibrium counterpart, are established in driven systems?

July 9 - August 6
Astrophysics of Gravitational Radiation Sources and Multimessenger Astronomy in the Era of LIGO Detections

Manuela Campanelli, Rochester Institute of Technology
Vassiliki Kalogera*, Northwestern University
Julian Krolik, Johns Hopkins University
Fred Rasio, Northwestern University
Steinn Sigurdsson, Pennsylvania State University

For centuries, astronomy has been restricted to observations of photons, for most of that time restricted further to the visible band. With the advent of both gravitational wave and neutrino observations of astrophysical sources, we have at last truly entered the epoch of multi-messenger astronomy. This workshop will explore the implications of this advance for the study of the objects that are the focus of this new discipline: black holes, both stellar-mass and supermassive, and neutron stars. We aim to bring together physicists and astrophysicists, experimentalists, observers, theorists, and computational astrophysicists in order to discover new ways for each approach to complement the others.

Among the specific topics to be discussed are:
- Merging black hole binaries, their gravitational radiation signatures, and tests of general relativity
- Prospects for improved source localization in both gravitational wave and neutrino events
- Formation and evolution of the LIGO source population, merging binaries containing stellar-mass black holes or neutron stars
- Gravitational wave, electromagnetic, and neutrino transients from merger events involving stellar-mass black holes and neutron stars
- Formation and evolution of black hole binaries up the mass-scale, from intermediate mass to supermassive
- Multi-messenger signals from black hole binaries of all masses: photons, neutrinos, direct and indirect (e.g. pulsar timing) detection of gravitational waves

July 23 - August 27
Reaching New Summits: The LHC at Full Strength

Radja Boughezal, Argonne National Laboratory
Mariangela Lisanti Princeton University
Patrick Meade,, Stony Brook University
Michele Papucci*, Lawrence Berkeley National Laboratory
Matt Schwartz, Harvard University

The LHC has already provided us with the monumental discovery of a Higgs-like boson, but has thus far left us with more open questions than answers. After reaching its design energy of 13 TeV last year, by summer 2017 it will have accumulated more integrated luminosity than in Run I. With this increased amount of data it will be possible to search for deviations from Standard Model (SM) predictions with more precision than possible in Run I. The properties of the Higgs will be studied in more detail, and new production channels will be accessible for the first time. This could provide clues about the underlying nature of electroweak symmetry breaking, which remains a primary motivator for theories of new physics. In addition, many new processes will be probed in detail for the first time, providing new windows onto BSM physics. However, the increase in center-of-mass energy in Run II has led us into the "Sudakov Zone", in which the combination of QCD and electroweak corrections must be studied in detail in order to enable discoveries in the high-mass tails of the distributions. Furthermore, the order of magnitude luminosity increase at the LHC will not be matched again until the next decade and makes summer 2017 the most crucial time in the near future to respect on the implications for BSM physics, especially if new discrepancies with the SM necessitating a BSM physics explantation will build up before then. This workshop aims at gathering experts from different communities of particle theory needed to decipher what the LHC provides and to study the implications for theoretical models: experts in model building, theorists skilled in SM phenomenology and precision calculations, as well as key experimentalists are needed to make progress in interpreting LHC results and planning for future searches.

August 6 - August 27
Quantum Criticality in Metallic Systems

Sudip Chakravarty, University of California, Los Angeles
Andrey Chubukov*, University of Minnesota
Piers Coleman, Rutgers University
Peter Woelfle, Karlsruhe Institute of Technology

In recent years there has been resurgence of interest in the problem of quantum criticality of metals, which fundamentally challenges our understanding of electronic behavior at the quantum level. A confluence of new developments on the experimental front, driven by new experimental techniques and the discovery of new materials appears to pose more questions than answers. This workshop will address the outstanding problems of quantum-critical behavior in systems with Fermi surfaces and in systems with low-energy excitations around particular points in momentum space, such as graphene and Weyl semi-metals. Materials of interest include heavy fermion metals, cuprates, iron based superconductors and other strongly correlated systems. In these systems the Landau Fermi liquid paradigm breaks down at criticality and there is no natural small parameter for a conventional perturbative expansion. A number of non-perturbative schemes have been proposed, such as the 1/N expansion, dimensional regularization, self-consistent strong coupling treatment. The workshop will offer a forum for assessments of the current state of the art in the understanding of quantum-critical and non-Fermi liquid behavior in metals, identifying the outstanding unsolved problems, and the most promising directions for new theoretical research in this field.

August 20 - September 17
Active Living Matter

Chase Broedersz, Princeton University
Nikta Fakhri, Massachusetts Institute of Technology
Fred MacKintosh*, Vrije Universiteit Amsterdam
Joshua Shaevitz, Princeton University

The aim of this workshop is to bring together a group of physicists, engineers, and biologists to discuss the physics of biological and soft matter systems far from equilibrium. Our primary goal is to identify the key experimental and theoretical challenges to uncovering the principles of collective non-equilibrium dynamics in biological systems, from the intracellular to the organism scale. The major themes of the workshop will include:

1. Active mechanics and dynamics in cells and collections of cells
2. Statistical mechanics of sensing, inference, and adaptation
3. Active matter

August 27 - September 17
Developing New Tools for Dark Matter Searches

Dmitry Budker, Johannes Gutenberg University Mainz
Yonatan Kahn, Princeton University
Maxim Pospelov, University of Victoria
Kathryn Zurek*, Lawrence Berkeley National Laboratory

The goal of this workshop is to bring together theorists and experimentalists from across a broad spectrum of disciplines to generate new ideas and directions in dark matter detection. This includes experts both in devices capable of measuring the minute energy depositions often typical of lighter-than-WIMP dark matter, as well as those working on more traditional New Physics probes such as beam dump experiments. We also plan to address new ways of looking for the ultra-light dark matter using precision AMO tools (for example, clocks, magnetometry, and gravitational wave interferometers). It is an open-ended journey, where unconventional ideas, diverse expertise and imagination are required!

August 27 - September 17
Vorticity in the Universe: From Superfluids to Weather and Climate, to the Universe

James Cho Queen Mary, University of London
John Marston*, Brown University
Heloise Meheut, Observatoire de la Cote d’Azur
Peter B. Weichman, BAE Systems

Vorticity is encountered in nearly all areas of science – and on an astonishing range of scales. It is encountered in Bose-Einstein condensates, biofluids and biolocomotions, boundary layers, fusion reactors, planetary atmospheres, oceans and climates, stellar and galactic flows, as well as the early Universe. Yet, the viewpoints, analysis tools, and applications of vorticity in all of these areas are rarely compared and contrasted among the different communities. A more global perspective and generalized ‘vorticity thinking’ can be of tremendous mutual benefit: such thinking has already revolutionized understanding in many aspects of modern atmosphere and ocean dynamics and is starting to make significant inroads in plasma physics and astrophysics. In view of this, this workshop will bring together leading researchers of vorticity from different areas of physics. The aim is to provide an opportunity to: i) share the latest research findings and tools in a focused way, ii) stimulate innovative ideas and collaborations, and iii) set new research directions.