What is the point of boson sampling? - Thomas Brougham

Hello everyone,

This week's presenter is Thomas from Quantum Theory group. Please find details of the talk below:

Title: What is the point of boson sampling?
Time: 3pm on 30th August 2018
Venue: 257 Kelvin Building

Abstract:

In principle, quantum computers could provide an exponential speed-up on certain problems.  This would mean that problems which are currently intractable could be solved efficiently.  For example, one could quickly find the prime factors of extremely large numbers and thus crack RSA cryptography.

While this should work in principle, we don’t have any evidence that such exponential speed-ups would ever be possible in practice.  Realistic experimental situations could render this quantum advantage negligible for interesting problems.  It is for this reason that there is a great interest to show that an exponential quantum advantage can be realized in an experiment.  However, building a full quantum computer is rather difficult.  A simpler approach is to build an optical experiment that efficiently solves one single problem.  This is the idea behind boson sampling, which uses light within a passive linear optical network.   A full experimental demonstration of boson sampling would prove that quantum systems really can efficiently solve seemingly intractable problems.

Realizing a demonstration of boson sampling would be a great technical achievement.  However, the boson sampling problem is not very interesting in of itself.  In this talk I will argue that boson sampling could be used for other tasks.  For example, it can be used within cryptography and to help simulate the dynamics of certain quantum systems.  This would mean that while a boson sampler is not a full quantum computer, it could still have some applications.

See you all there!

Pavi.