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Culs-de-sac and open ends
David Gross - Universität zu Köln
Unitary design: bounds on their size
Andrew Scott - Griffith University
Quantum state tomography from yes/no measurements
Martin Roetteler - NEC Laboratories America (Princeton)
Seeking Symmetries of SIC-POVMs
Markus Grassl - Max Planck Institute for the Science of Light
SIC Triple Products
Marcus Appleby - Queen Mary University of London
Why I care
Chris Fuchs - University of Massachusetts Boston
IR modification of gravity and the forbidden mass range of graviton in de Sitter Space
Yanwen Shang - Citigroup Incorporated
New CMB results
Richard Bond - University of Toronto , Jon Sievers - McGill University - Department of Physics , Mike Nolta - University of Toronto
Observational Evidence for Massive Gravity
Niayesh Afshordi - University of Waterloo
Topologically Massive AdS Gravity
Steve Carlip - University of California, Davis
Cosmology with 21cm sky
Ue-Li Pen - University of Toronto , Tzu-Ching Chang - National Aeronautics and Space Administration
Times of arrival and gauge invariance
Siddhant Das - Ludwig-Maximilians-Universität München (LMU)
"We revisit the arguments underlying two well-known arrival-time distributions in quantum mechanics, viz., the Aharonov-Bohm and Kijowski (ABK) distribution, applicable for freely moving particles, and the quantum flux (QF) distribution. An inconsistency in the original axiomatic derivation of…
Inequivalent clocks in quantum cosmology
Steffen Gielen - University of Sheffield
Quantum cosmology faces the problem of time: the Universe has no background time, only interacting dynamical degrees of freedom within it. The relational view is to use one degree of freedom (which can be matter or geometry) as a clock for the others. In this talk we discuss a cosmological model of…
Relational dynamics in an emergent spacetime context
Luca Marchetti - Okinawa Institute of Science and Technology Graduate University
I discuss the new dimension that the relational approach to the problem of time takes in quantum gravity contexts in which spacetime and geometry are understood as emergent. I argue that, in this case, the relational strategy is best realized at an approximate and effective level, after suitable…
Relational observables and quantum diffeomorphisms on the worldline
Leonardo Chataignier - Universität zu Köln
"Candidate theories of quantum gravity must answer the questions: how can the dynamics of quantum states of matter and geometry be defined in a diffeomorphism-invariant way? How are the quantum states related to probabilities in the absence of a preferred time? To address these issues, we discuss…
Quantum gravity Vs unimodular quantum gravity
Antonio Pereira - Universidade Federal Fluminense
Strong gravity tests indicate that general relativity is a very accurate description of the classical dynamics of spacetime even at extreme regimes. Yet, the same dynamics can be described by "alternative" versions of general relativity such as unimodular gravity. In the quest for a quantum theory…
Measuring Quantum Discreteness of Time in the Lab with Gravity Entanglement Interference
Carlo Rovelli - Aix-Marseille University
The concrete perspective of using interference to measure Gravity Induced Entanglement in the lab is a very exciting development for quantum gravity. While the measurements considered so far only test the nonrelativistic regime, the same technique might allow access to genuine relativistic quantum…
Measuring time with stationary quantum clocks
Mischa Woods - ETH Zurich
Time plays a fundamental role in our ability to make sense of the physical laws in the world around us. The nature of time has puzzled people –- from the ancient Greeks to the present day -– resulting in a long running debate between philosophers and physicists alike to whether time needs change to…
Time in Physics and Intuitionistic Mathematics
Nicolas Gisin - Université de Genève
"Physics is formulated in terms of timeless axiomatic mathematics. However, time is essential in all our stories, in particular in physics. For example, to think of an event is to think of something in time. A formulation of physics based of intuitionism, a constructive form of mathematics built on…
Dynamics of Primordial Black Holes in the Early Universe
Derek Inman - University of Toronto
If dark matter is composed at least partially of primordial black holes (PBHs) then structure formation occurs very differently than in standard particle dark matter scenarios. PBH binaries, halos and other structures can form at very early redshifts and the resulting nonlinear dynamics can change…
God does not play dice (He plays sudoku)
Emily Adlam - Chapman University
I argue that modern physics gives us good reason to take seriously the possibility of laws which are non-local, global, or in some other way non-dynamical. I set out a general framework for lawhood which does not presuppose the standard kinematical/dynamical split, and I apply it to the problem of…
Time and Noether's (first) theorem
Harvey Brown - University of Oxford
"It is widely believed that the homogeneity of time is the symmetry related by Noether's (first) theorem to the conservation of energy, and indeed that it explains energy conservation. Both claims are questionable, and in particular seemingly hard to reconcile with the modern version of Noether's…