Seminar

Yaoyun Shi, University of Michigan

How can one be certain that the output of an alleged random
number generator is indeed random? This question is important not
only for the efficiency and the security of information
processing, but also for understanding how intrinsically
unpredictable events are possible in Nature. Practical random
number generators have often been found to be insecure. All
existing theoretical solutions require a certain form of
independence among two or more sources of randomness, a condition

Carl A. Miller, University of Michigan, Ann Arbor, USA

Recently Yaoyun Shi and I gave the first proof of security for robust exponential quantum randomness expansion. This talk will be an overview of the problem and a discussion of the techniques used in our proof.

Ramy El Ganainy, Michigan Technological University

Katanya Kuntz,  University of New South Wales, Canberra, Australia

We simultaneously generate photon-subtracted squeezed vacuum and squeezed vacuum at three frequencies from an optical parametric oscillator by utilizing its frequency non-degenerate sidebands. Quantum non-Gaussianity is demonstrated by applying a novel character witness.

Laura Mancinska, Centre for Quantum Technologies, Singapore

Quantum entanglement is known to provide a strong advantage in many two-party distributed tasks. We investigate the question of how much entanglement is needed to reach optimal performance. For the first time we show that there exists a purely classical scenario for which no finite amount of entanglement suffices. To this end we introduce a simple two-party nonlocal game $H$, inspired by Hardy's paradox. In our game each player has only two possible questions and can provide bit strings of any finite length as answer.

Ivette Fuentes, The University of Nottingham

Quantum technologies are widely expected to bring about many key technological advances this century. Quantum metrology and quantum information have been so far successfully applied in the design of devices that outperform their classical counterparts by exploiting quantum properties. Impressively, the quantum era is now reaching relativistic regimes. Table-top experiments demonstrate relativistic effects in quantum fields and long range quantum experiments will soon reach regimes where relativity kicks in.

Sevag Gharibian, University of California, Berkeley

The study of ground spaces of local Hamiltonians is a fundamental task
in condensed matter physics. In terms of computational complexity
theory, a common focus in this area has been to estimate a given
Hamiltonian’s ground state energy. However, from a physics
perspective, it is often more relevant to understand the structure of
the ground space itself. In this paper, we pursue the latter direction
by introducing the notion of “ground state connectivity” of local

David Elkouss, Universidad Complutense de Madrid

Omar Fawzi, McGill University

The goal of two-party cryptography is to enable Alice and Bob to solve tasks in cooperation even if they do not trust each other. Examples of such tasks include bit commitment, coin flipping and oblivious transfer. Unfortunately, it has been shown that even using quantum communication, none of these tasks can be implemented when the adversary is completely general.

Sahel Ashhab, Qatar Environment and Energy Research Institute, Qatar Foundation

Cavity QED in the ultrastrong-coupling regime & Landau-Zaner-Stückelberg interfereometry