ELFT HÍRADÓ

[Zoltan Zimboras <zimboras AT gmail.com>]

Dear Colleague,

The Budapest Distributed Quantum Systems seminar series continues with the
following talk:

Byzantine Fault Tolerance using Entangled Quantum States

Andras Palyi (Budapest University of Technology and Economics, BME)


Time: March 4, Thursday, 14:30

Location: online in Teams

Teams link to join the talk:

https://teams.microsoft.com/l/meetup-join/19%3afcecd32ff381436ebd80d58b5a3dfb82%40thread.tacv2/1613738148091?context=%7b%22Tid%22%3a%225d471751-9675-428d-917b-70f44f9630b0%22%2c%22Oid%22%3a%2246f47102-edf5-49a1-be82-b086ae96c83b%22%7d

Please see the website for more details on the seminar series:

https://physics.bme.hu/dqs2021?language=en

Best regards,

Zoltan Zimboras

on behalf of the organizers

Lorant Farkas (Nokia Bell Labs, Budapest)

Andras Palyi (Budapest University of Technology and Economics)

Zoltan Zimboras (Wigner Research Centre for Physics, Budapest)

= = =

About the speaker: Andras Palyi is a theoretical physicist, working as an
associate professor at the Department of Theoretical Physics, Budapest
University of Technology and Economics. He obtained his PhD in
condensed-matter theory at the Eotvos Lorand University in Budapest, and
held a postdoc position at the University of Konstanz, in Germany, before
moving back to Budapest in 2011. Since his PhD, Andras has been doing
research at the interface of condensed-matter physics and quantum
information, doing theory work toward the goal of practical, experimental
quantum information processing.


Abstract:

In distributed computing, a byzantine fault is a condition where some
components of a multi-component system fail, but it is unclear which
components fail and which ones function properly. A deterministic protocol
to reliably broadcast information in such a setting was proposed by Pease
et al. [1]. More recent ideas built upon distributed entangled quantum
states [2,3,4] are worth considering as they offer a reduced communication
cost. In this talk, I will outline recent unpublished results of a Budapest
collaboration among researchers of Nokia Bell Labs, BME and the Wigner
Research Centre for Physics. I will introduce a family of quantum-aided
weak broadcast protocols. I will show our results of a resource
optimization procedure, illustrating the engineering aspects of future
deployment of such protocols in practice. The protocols I'll discuss rely
on a specific 4-qubit entangled resource state. Following earlier work
demonstrating the suitability of noisy intermediate-scale quantum (NISQ)
devices for the study of quantum networks [5], I will show how to prepare
our resource state on publicly available IBM quantum-computer prototypes.
Finally, I plan to discuss future research directions toward quantum-aided
byzantine fault tolerance.

[1] M. Pease et al., J. ACM 27, 228 (1980).

[2] M. Fitzi, N. Gisin, U. Maurer, Phys. Rev. Lett. 87, 217901 (2001).

[3] A. Cabello, Phys. Rev. A 68, 012304 (2003).

[4] S. Gaertner et al., Phys. Rev. Lett. 100, 070504 (2008).

[5] P. Pathumsoot et al., Phys. Rev. A 101, 052301 (2020)