Events

John Wright, Massachusetts Institute of Technology (MIT)

In the area of quantum state learning, one is given a small number of "samples" of a quantum state, and the goal is use them to determine a feature of the state. Examples include learning the entire state ("quantum state tomography"), determining whether it equals a target state ("quantum state certification"), or estimating its von Neumann entropy. These are problems which are not only of theoretical interest, but are also commonly used in current-day implementation and verification of quantum technologies.

An introduction to making scientific figures with Illustrator and Blender

Special guest speaker: Christopher Gutierrez, University of British Columbia

Scientific research can be a slow and laborious process. The absolutely final step in the process is to then communicate your exciting scientific findings to other scientists both in and outside of your field. Yet it is often at this final step where the least amount of time is spent.

Tobias Fritz, Perimeter Institute

Similar to how commutative algebra studies rings and their ideals, the protagonists of real algebra are ordered rings. Their interplay between algebra and geometry is studied in terms of Positivstellen- stze, real analogs of the Nullstellensatz, which go back to Artin's solution of Hilbert's 17th problem. I will describe some of the state of the art in this eld, and then introduce a new Positivstellensatz which unies and generalizes several of the existing ones.

Journal club presentation:

"Experimental superposition of orders of quantum gates" by Procopio et. al.

(Nature Comms 6, 7913 (2015)

Arash Ahmadi, Institute for Quantum Computing

Quantum computers achieve a speed-up by placing quantum bits (qubits) in superpositions of different states. However, it has recently been appreciated that quantum mechanics also allows one to ‘superimpose different operations’.

Candidate: Guofei Long

Supervisors: David Cory and Guo-Xing Miao

Adina Luican-Mayer, University of Ottawa

Innovative technologies have a history of capitalizing on the discovery of new physical phenomena, often at the confluence of advances in material characterization techniques and innovations in design and controlled synthesis of high-quality materials. Pioneered by the discovery of graphene, atomically thin materials (2D materials) hold the promise for realizing physical systems with distinct properties, previously inaccessible.

Chinmay Nirkhe, University of California, Berkeley

We study approximate quantum low-density parity-check (QLDPC) codes, which are approximate quantum error-correcting codes specified as the ground space of a frustration-free local Hamiltonian, whose terms do not necessarily commute. Such codes generalize stabilizer QLDPC codes, which are exact quantum error-correcting codes with sparse, low-weight stabilizer generators (i.e. each stabilizergenerator acts on a few qubits, and each qubit participates in a few stabilizer generators).

Nicole Yunger Halpern, Harvard University Department of Physics

Thermodynamics has shed light on engines, efficiency, and time’s arrow since the Industrial Revolution. But the steam engines that powered the Industrial Revolution were large and classical. Much of today’s technology and experiments are small-scale, quantum, and out-of-equilibrium. Nineteenth-century thermodynamics requires updating for the 21st century. Guidance has come from the mathematical toolkit of quantum information theory.

Supartha Podder, University of Ottawa

In 2011 Harry Buhrman, Serge Fehr, Christian Schaffner and Florian Speelman proposed a new measure of complexity for finite Boolean functions, called "The Garden-hose complexity". This measure can be viewed as a type of distributed space complexity where two players with private inputs compute a Boolean function co-operatively. While its motivation mainly came from the applications to position based quantum cryptography, the playful definition of the model is quite appealing in itself.

Martin Savage, Institute for Nuclear Theory 

Recently, Silas Beane, David Kaplan, Natalie Klco and I considered the entanglement power of the S-­‐matrix describing low-­‐energy hadronic interactions, and the implications of particular limits. We found that vanishing entanglement power occurs at points of emergent global symmetries, which are seen to be consistent with nature and also recent lattice quantum chromodynamics (QCD) calculations. I will discuss aspects of these results.