This series covers all areas of research at Perimeter Institute, as well as those outside of PI's scope.
The covariant formulation of loop quantum gravity has developed strongly during the last few years. I summarize the current definition of the theory and the results that have been proven. I discuss what is missing towards of the goal of defining a consistent quantum theory whose classical limit is general relativity.
Mass, a concept familiar to all of us, is also
one of the deepest
mysteries in nature. Almost all of the mass in the
visible universe,
you, me and any other stuff that we see around us, emerges from a
quantum field theory, called QCD, which has a completely negligible
microscopic mass content. How does QCD and the family of
gauge
theories it belongs to generate a mass?
This class of non-perturbative problems remained largely elusive despite much
In this lecture I will describe in simple terms the basic ideas of gauge symmetry in phase space, its consequences in the form of a deeper redefinition of space and time, and some observable manifestations of an extra space and extra time dimensions.
Entropy plays a fundamental role in quantum information theory through applications ranging from communication theory to condensed matter physics. These applications include finding the best possible communication rates over noisy channels and characterizing ground state entanglement in strongly-correlated quantum systems. In the latter, localized entanglement is often characterized by an area law for entropy. Long-range entanglement, on the other hand, can give rise to topologically ordered materials whose collective excitations are robust against local noise.
Black holes lead a double life, simultaneously the dark, enigmatic, hairless consequence of general relativity and the powerful engines lurking at the hearts of galaxies with cosmological consequences.
Quantum gravity is about finding out what is the more fundamental nature of spacetime, as a physical system. Several approaches to quantum gravity, suggest that the very description of spacetime as a continuum fails at shorter distances and higher energies, and should be replaced by one in terms of discrete, pre-geometric degrees of freedom, possibly of combinatorial and algebraic nature.
Condensed matter systems offer a unique opportunity to study "emergence".