Conference/School

Over the past three decades, the idea of a path integral over geometries, describing gravity in various dimensions, has become increasingly central to many areas of theoretical physics, including string and M-theory, holography and quantum aspects of black holes and cosmology.

In each of these areas, the path integral is frequently invoked as a formal device although, as practitioners will admit, except in very special cases the basic formula remains undefined. Typically, classical saddle points are discussed, whether real or complex, but the required integrals are left unperformed.

This state of affairs is untenable because it leaves the theory on a shaky footing and hence does not permit a sound comparison of theoretical predictions with observations. The time has come to critically reassess the foundational ideas of the path integral for gravity, including its definition, evaluation and interpretation; to identify problems with
existing uses and claims based on it, and to seek improvements. The workshop will focus on the continuum theory and its semiclassical limit, with applications to cosmology, black holes and holography. In particular, the notion of a “Euclidean path integral” for a “wavefunction of the universe” will be addressed.

To this effect we intend to revisit discussion of “quantum geometrodynamics” from the path integral viewpoint and to pursue various applications. The developments in this direction that took place in the late 1970's and early 1980's were not incorporated in subsequent efforts, where the emphasis shifted to using a classical background with quantum fluctuations superimposed on it, a split which although useful in particular approximations can hardly be imagined to lie at the  foundation of the theory. The revival of the discussion of the foundation of the path integral for gravity is made timely, we believe, by the introduction of new global methods such as Picard-Lefschetz theory.

The format of the workshop will be unusual. For the first three days, the mornings will begin with a longer, introductory lecture by each of the three organisers, setting out some of the foundational issues. This will be followed by shorter lectures by the participants, tackling the same foundational questions. The morning lectures, held in the Bob room, will be open to all Perimeter residents and visitors. They will be recorded and made available for viewing on PIRSA. Afternoons will be devoted to friendly and informal discussions, with participants invited to offer short contributions which follow up or develop points raised in the mornings, within a relaxed and highly conducive environment. Participation in these afternoon discussion sessions, as well as social events associated with the workshop, will be limited to registered workshop participants. The last two days of the workshop will be an opportunity for participants to continue discussions on topics which emerge as of greatest general interest, as well as to follow up in smaller groups on technical points or new ideas.

The past decade has witnessed significant breakthroughs in understanding the quantum nature of black holes, with insights coming from quantum information theory, numerical relativity, and string theory.  At the same time, astrophysical and gravitational wave observations can now provide an unprecedented window into the phenomenology of black hole horizons.  This workshop seeks to bring together leading experts in these fields to explore new theoretical and observational opportunities and synergies that could improve our physical understanding of quantum black holes.

In the last few years there has been a resurgence of interest in small scale high sensitivity experiments that look for new forces and new particles beyond the Standard Model. They promise to expand our understanding of the Cosmos and possibly explain mysteries such as Dark matter in a way that is complementary to colliders and other large scale experiments. There is a number of different physics motivations and approaches currently being explored in many on-going and newly proposed experiments and they often share common experimental techniques.Many workshops in this field focus on the theory motivations behind these experiments without emphasis on the details of the experimental techniques that enable precision measurements. There is also substantial experimental expertise across many fields, often outside of fundamental physics community, that can be relevant to ongoing and proposed experiments.Thus, we decided to organize the workshop around some of the common experimental techniques. We hope it will be educational for both experimentalists and theorists and lead to discussions on the best way forward. We would like to bring together experimentalists with different expertise in the hope that it will lead to new ideas through interdisciplinary interactions. For theorists, we expect it to provide better appreciation of the challenges and opportunities in improving the sensitivity of precision measurement experiments.

The Kitaev quantum double models are a family of topologically ordered spin models originally proposed to exploit the novel condensed matter phenomenology of topological phases for fault-tolerant quantum computation. Their physics is inherited from topological quantum field theories, while their underlying mathematical structure is based on a class of Hopf algebras. This structure is also seen across diverse fields of physics, and so allows connections to be made between the Kitaev models and topics as varied as quantum gauge theory and modified strong complementarity. This workshop will explore this shared mathematical structure and in so doing develop the connections between the fields of mathematical physics, quantum gravity, quantum information, condensed matter and quantum foundations.

The sixth annual Women is Physics Canada (WIPC) conference is hosted by the University of Waterloo, Faculty of Science, Department of Physics & Astronomy and the Institute for Quantum Computing. The conference will run July 26-28, 2017. WIPC 2017 will bring together early career scientists to present their research and hear plenary talks from leaders in physics.

For more information please visit the WIPC 2017 website.

2017 marks 50 years since the seminal 1967 article of Kochen and Specker proving that quantum theory fails to admit of a noncontextual model.  Despite the fact that the Kochen-Specker theorem is one of the seminal results concerning the foundations of quantum theory, there has never been a large conference dedicated to the subject.  The 50-year anniversary of the theorem seems an opportune time to remedy this oversight.  Furthermore, in the last decade, there have been tremendous advances in the field.  New life has been breathed into the subject as old conceptual issues have been re-examined from a new information-theoretic perspective. Importantly, there has been great progress in making the notion of noncontextuality robust to noise and therefore experimentally testable.  Finally, there is mounting evidence that the resource that powers many quantum advantages for information processing is contextuality.  In particular, it has been shown to underlie the possibility of universal quantum computation.  Many groups worldwide are actively engaged in advancing our knowledge on each of these fronts and in deepening our understanding of the distinction between quantum and classical theories through the lens of contextuality.  Through this conference, we aim to bring together leading researchers in the field in order to develop a broader perspective on the issues, draw connections between different approaches, foster a more cohesive community, and set objectives for future research.

Continuing investment in fundamental weakly-coupled science, primarily through neutrino experiments and dark matter searches, prompts the question: is the maximum possible scientific information going to be extracted from these experiments? Are there new creative uses of the existing and planned facilities that would advance our knowledge of fundamental physics? Are there physics targets that have been overlooked by the current approach? This workshop will attempt to advance discussion of these topics, and concentrate on non-traditional ideas and alternative methods of probing new physics, both at underground laboratories and at high-intensity accelerators. The workshop aims to complement the large international conference, Topics in Astroparticle and Underground Physics 2017, to be held in Sudbury ON July 24-28, by directly preceding that meeting.