* denotes the organizer responsible for participant diversity in the workshop

May 27 - September 16
Individual Research

Physicists are encouraged to apply as individual researchers to work on their own projects at 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 27 - September 16
Working Group

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

May 27 - June 17
From Physics to Applications of Quantum Computers

Andrew Childs, University of Maryland
Barbara Jones*, IBM Research - Almaden
Chris Monroe, University of Maryland
Matthias Troyer, Microsoft Research

This workshop will be on the physics of quantum computers and their early applications, from a variety of vantage points. We aim to attract experimentalists, theorists, computational physicists, as well as quantum information theorists. In addition to advances in quantum algorithms and computation, we will cover the quantum simulation of models in condensed matter, quantum chemistry, and other fields. The dual areas of qubit errors and fault-tolerance will also be covered. By including both theorists and experimentalists, we intend to foster discussion more broadly on the co-design of quantum applications with various platforms (trapped ions and atoms, superconducting qubits, quantum dots and impurities in solids, and topological states, etc.). Likewise, by bringing together algorithm theorists with computational physicists, we intend for discussion and interplay to lead to progress and new ways of thinking about quantum application spaces.

May 27 - June 17
The Physics of Behavior:
Movement, Control, and Learning

Gordon J. Berman, Emory University
Daniel I. Goldman, Georgia Institute of Technology
Stephanie E. Palmer, University of Chicago
Greg J. Stephens, Vrije Universiteit Amsterdam & Okinawa Institute of Science and Technology

During the last 100 years, the interaction of physical and life sciences has led to tools and insights that have enabled incredible advances in the discovery and detailed description of the building blocks that constitute living systems. Relative to the study of these important constituent parts, though, fewer physicists have focused on the organizing principles that govern whole-organism behaviors. Recent studies have pointed to a growing role for physics in biological behavior: physics-based research can create novel insights into the generating mechanisms for behaviors that are common to many species. This workshop will highlight current directions in the biophysics of organismal behavior, bringing together researchers studying systems ranging in scale from single cells to neural circuits to large groups of animals. The workshop will focus on how physical principles and constraints can define an organism’s strategies for survival in a dynamic, noisy, and resource-limited world. Specific topics to be discussed will include the mechanics of locomotion in complex environments, algorithms and principles for learning and adaptation, social and collective dynamics, and the neural control of behavior.

June 3 - June 24
Physical Principles Governing the Organization
of Microbial Communities.

Kerwyn Casey Huang, Stanford University
Rachel Dutton, University of California San Diego
Alvaro Sanchez, Yale University
Jeff Gore*, MIT

Nearly every environment on earth is populated with a diverse community of microorganisms bound together by a web of interconnected metabolic interactions. Microbial communities direct global biogeochemical cycling, bioremediation, and disease prevention. Interest in the physical properties of microbial communities is as old as microbiology and imaging. In the 1600s, Antonie van Leeuwenhoek exploited his newfound powers of microscopy to discover that microorganisms living on and in his body showed a huge range in shape and size. This first rudimentary evidence that the human body harbors a microbiota also established the first hint of complex microbial ecosystems. Now, almost 400 years later, a renaissance of the study of microbiota spatial organization, driven by coincident revolutions in imaging and sequencing technologies, is revealing functional relationships between the biogeography and organizational principles of multispecies microbial communities, and with the health of the hosts (including humans) and the planet itself. The advent of low-cost, high-throughput sequencing is producing a revolution in the microbiota field. Previously, assessing the composition of a multispecies community was a daunting task doomed to incompleteness due to the challenges of identifying conditions in which individual species could be cultured. Now, compositional profiling has become routine, empowering experiments in which the effect of perturbations to a community can be rapidly and accurately assessed. This newfound capability presents enormous opportunities for physics and physicists to advance this incredibly exciting field. The goals of the program are to provide unique opportunities to deconstruct microbial communities and identify governing principles that broadly inform biology, physics, ecology, and evolutionary biology.

June 17 - July 8
The Astrophysics of Massive Black Hole Mergers:
From Galaxy Mergers to the Gravitational Wave Regime

Julie Comerford*, University of Colorado, Boulder
Crystal Martin, University of California, Santa Barbara
George Privon, University of Florida
David Sanders, University of Hawaii

While it is now clear from LIGO that stellar mass black hole (BH) binaries exist and merge, the existence of in-spiraling and merging supermassive black holes (SMBHs) has yet to be demonstrated. This workshop will address the open astrophysical questions regarding the precursors to SMBH binaries in the gravitational wave regime. Specifically, what are the rates at which binary SMBHs enter an evolutionary phase where their evolution is dominated by gravitational wave emission and what are the properties (masses, mass ratio, orbits, etc.) of those binaries? Answering these questions is critically important in planning for low-frequency GW observatories such as the Laser Space Interferometer Antenna (LISA) and pulsar timing arrays (PTAs). This workshop will address the evolution of SMBH pairs from the early stages of galaxy mergers, through binary formation and hardening, up to the gravitational wave regime. This includes formation of the first massive BHs, the frequency of galaxy mergers, supermassive black hole growth during galaxy mergers, and how the systems dynamically evolve from galaxy merger to BHs sinking into the galaxy center - addressed from both observational/experimental and theoretical perspectives.

June 17 - July 15

Perfect Pixels. Accurate Astrophysics. Correct Cosmology.

Robert Lupton, Princeton University
Rachel Mandelbaum, Carnegie Mellon University
Hiranya Peiris, Oskar Klein Centre for Cosmoparticle Physics Stockholm
Andrew Pontzen*, University College London

We are entering a transformative period in observational cosmology. Surveys starting in 2019 promise to solve key problems in cosmology and astrophysics — but only if we develop new approaches for handling the volume and complexity of the data. Extracting robust cosmological information from these surveys is a major challenge that will require development and validation of analysis methods at each step of the chain from raw pixels to cosmology. A quantitative handle on instrumental and pipeline systematics and astrophysical contaminants will be essential. This workshop will bring together experts in a range of fields to take a critical look at the full analysis process, which starts with the hardware and ends with accurate astrophysics and correct cosmology.

June 24 - July 29

Topological Phases and Excitations
of Quantum Matter

James Analytis, University of California Berkeley
Fiona Burnell, University of Minnesota
Xie Chen*, California Institute of Technology
Liang Fu, Massachusetts Institute of Technology
Michael Hermele, University of Colorado Boulder

The last 10 years have seen remarkable developments in our understanding of topological phases of matter. Topological quantum solids are widespread, and a unified theoretical framework of many of their unusual electronic properties is emerging. Rapid experimental progress towards engineering non-Abelian topological excitations in quantum devices may soon lay the foundation for topological quantum computation. Recent theoretical developments in our understanding of topological quantum matter have shed new light on many unsolved problems connected to field theory dualities, the fractional quantum Hall effect, superconductor-insulator transition, quantum spin liquids, and heavy fermion systems. New perspectives on the role of topology in three-dimensional and in out-of-equilibrium quantum systems are also attracting considerable interest. The aim of this workshop is to bring together theorists and experimentalists from different fields to address this broad range of problems in the physics of topological phases and excitations.

July 15 - August 5

Unveiling the Physics of Protoplanet Formation:
Connecting Theory to Observations

Andrea Isella, Rice University
Til Birnstiel, LMU Munich
Nienke Van Der Marel, University of Hawaii
Ruobing Dong, University of Arizona

Unprecedented high angular resolution imagery of circumstellar disks have revealed rings, spirals, and crescents in the gas and dust distribution around young (< 5 million years) pre-main sequence stars. These structures are the signposts of forming planetary systems, and probe the mass, orbit, and formation timescale of young planets. Observations have also revealed spatial variations of the dust particle sizes and changes in the chemical composition of the circumstellar gas. These constrain the processes responsible for the agglomeration of the large bodies (asteroids and comets) that are required to initiate the formation of rocky planets. The recent results stimulate a revision of planet formation models and push for new theoretical studies aimed at understanding the interactions between disks and planets, as well as the physics of solid particles in gaseous disks. The goal of this workshop is to bring together theorists and observers to collaborate on unveiling the key physical processes responsible for the formation of planets and the evolution of solids in protoplanetary disks.

July 29 - August 26

The Flavor of New Physics in Collisions

Gudrun Hiller* Technical University of Dortmund
Wolfgang Altmannshofer University of Cincinnati
Yotam Soreq, MIT
Jure Zupan, University of Cincinnati

The workshop will bring together experts working on BSM physics and on flavor physics, both theorists and experimentalists, and provide a common working and discussion arena between these groups of experts. The workshop is motivated, but not limited to the topics that received an increased interest due to recent experimental anomalies in b quark transitions: flavor and new signatures at high pT at ATLAS and CMS, the physics for high luminosity LHCb, new theories of flavor, implications for Higgs physics, lepton universality violation and lepton flavor violation, implications of experimental results for models of baryogenesis, the interplay between flavor physics and solutions to the hierarchy problem.

August 5 - August 26

SYK Models: From Interacting Quantum Matter to Black Holes

Leon Balents*, University of California Santa Barbara
Marcel Franz, University of British Columbia
Xiaoliang Qi, Stanford University
Herman Verlinde, Princeton University

In 1993 Sachdev and Ye proposed a quantum mechanical model of a spin liquid with local critical behavior. In a series of lectures in the fall of 2015 Alexei Kitaev discussed a variant of this model and presented compelling arguments that its physics entails the holographic description of a black hole. The resulting Sachdev-Ye-Kitaev (SYK) model is remarkably simple, yet it encodes a great wealth of interesting physics. It consists of N Majorana fermions interacting among themselves via “democratic” all-to-all random interactions. Its solvability in the large-N limit is quite unusual for a strongly interacting system and makes the SYK model a fertile ground for explorations of the most fundamental mysteries in modern physics. Over the past two years, the SYK model became a subject of a massive interdisciplinary effort which uncovered its intriguing connections with a multitude of phenomena that are of great current interest. These include such seemingly disparate areas as quantum chaos and scrambling dynamics, thermalization and ergodicity, aspects of holographic duality and quantum gravity, holographic quantum matter and strongly correlated metals. Various generalizations and extensions of the model have been formulated and studied containing supersymmetry, interesting quantum phase transitions, extensions to higher dimensions, as well as versions that do not require randomness. Recently, experimental realizations in atomic and solid state systems have been proposed which may lead to tabletop experiments producing and probing artificial black holes. The workshop will build on these recent developments and bring together researchers in condensed matter physics, string theory, quantum gravity and quantum information theory interested in the SYK model and the related topics. We expect the resulting proceedings to be truly multidisciplinary and address some of the most fundamental questions facing physics today.

August 19 - September 16

Superconformal Field Theories and Geometry

Sakura Schafer-Nameki, University of Oxford
David R. Morrison*, University of California Santa Barbara
Alessandro Tomasiello, University of Milano-Bicocca

The goal of this summer 2018 workshop is to further develop the connection between superconformal field theories (SCFTs) and geometric constructions in string theory, in particular F-theory. Building on the recent success in classifying six-dimensional SCFTs within F-theory, the goal of this workshop is to extend this to SCFTs in lower dimensions. This will be achieved by bringing together string theorists and geometers, working on F-theory, as well as experts on holography and field theoretic aspects of SCFTs.

August 26 - September 16

Dynamics of the Milky Way System in the Era of Gaia

Andrew Wetzel, University of California, Davis
Sarah Loebman*, University of California, Davis
Robyn Sanderson, California Institute of Technology
Hans-Walter Rix, Max Planck Institute for Astronomy

A wealth of observational surveys are poised to revolutionize our understanding of the composition and formation of our Milky Way galaxy. This workshop will focus on observational analysis and theoretical modeling of stellar dynamics of the entire Milky Way system, from stars in the disk and bulge to the satellite dwarf galaxies, stellar streams, and stars throughout the halo. The workshop will occur at a watershed time for Galactic dynamics: shortly after the second data release from the Gaia satellite mission, which for the first time can constrain the full phase-space orbital distributions of stars throughout the Galaxy. In parallel, several ground-based surveys are measuring high-resolution spectra for millions of these stars, and the Hubble Space Telescope is providing high-precision proper motions of stars throughout the halo. The groundbreaking scale and breadth of this new view of the Milky Way challenges the community to develop new approaches for Galactic dynamics. This workshop will bring together observers, modelers, and simulators, to discuss (1) how to analyze this wealth of high-precision dynamics data and (2) how to develop accurate, cosmologically informed models to interpret them. The overarching goals are galactic archaeology, to understand the full 3D formation history of the entire Milky Way system, and near-field cosmology, to use stellar dynamics to measure the distribution and test the nature of dark matter.

August 26 - September 16

Understanding the Origin of the Baryon Asymmetry of the Universe

Lorenzo Ubaldi, SISSA
Ann Nelson, University of Washington
David Morrissey, TRIUMF
Seyda Ipek*, Fermilab

There is more matter than antimatter in the Universe. Several mechanisms of matter creation have been proposed to explain this asymmetry, and all of them appear to require new physics beyond the Standard Model. Despite a broad range of experimental searches, no experimental evidence for such new physics or the specific mechanism underlying the asymmetry has been found. The aim of this workshop is to bring together a diverse range of theoretical and experimental particle physicists to study new developments in our understanding of the baryon asymmetry. An emphasis will be placed on ideas that can potentially be tested in upcoming and planned experimental searches.