Hi all,
Unfortunately it looks like there may not be food after all - hope to see
you there anyway ;)
Ian
On Fri, May 11, 2018 at 1:17 AM Ian Kivlichan <ian.kivlichan(a)gmail.com>
wrote:
Hi all,
I will give group meeting today (Friday - usual time and place
otherwise!), with catering from Taco Bob. Title and abstract below.
Best,
Ian
-----------------
Quantum simulation of electronic structure with linear depth and
connectivity
As physical implementations of quantum architectures emerge, it is
increasingly important to consider the cost of algorithms for practical
connectivities between qubits. We show that by using an arrangement of
gates that we term the fermionic swap network, we can simulate a Trotter
step of the electronic structure Hamiltonian in exactly N depth and with
N^2/2 two-qubit entangling gates, and prepare arbitrary Slater determinants
in at most N/2 depth, all assuming only a minimal, linearly connected
architecture. We conjecture that no explicit Trotter step of the electronic
structure Hamiltonian is possible with fewer entangling gates, even with
arbitrary connectivities. These results represent significant practical
improvements on the cost of all current proposed algorithms for both
variational and phase estimation based simulation of quantum chemistry.
Additionally, we are investigating the algorithm's performance in the
context of universal fault-tolerant quantum devices.