ELFT HÍRADÓ

[Andras Palyi <palyi AT mail.bme.hu>]

Dear Colleague, 

The Budapest Distributed Quantum Systems seminar series starts on Feb 18 
Thursday, with the following talk:

Quantum-Secured Blockchain Protocol
Aleksey Fedorov (Russian Quantum Center, Moscow)

Time: Feb 18 Thursday, 14:30
Location: online in Teams

Teams link to join the talk:
https://teams.microsoft.com/l/meetup-join/19%3afcecd32ff381436ebd80d58b5a3dfb82%40thread.tacv2/1612988716663?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,
Andras Palyi

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: Dr. Aleksey Fedorov is the Junior Principal Investigator 
of the research group of Quantum Information Technologies at the Russian 
Quantum Center in Moscow, Russia. Aleksey studied Computer Science in Moscow, 
and obtained his PhD in Physics in Paris, in 2017. Currently he and his group 
studies the potential of quantum systems for information technology. Among 
other results, Aleksey's group has developed a protocol for a 
quantum-protected blockchain [Nature (London) 563, 465 (2018); Quantum Sci. 
Technol. 3, 035004 (2018)]. 

Abstract: The blockchain is a distributed ledger platform with high Byzantine 
fault tolerance, which enables achieving consensus in a large decentralized 
network of parties who do not trust each other. A paramount feature of 
blockchains is the accountability and transparency of transactions, which 
makes it attractive for a variety of applications ranging from smart 
contracts and finance to manufacturing and healthcare. Blockchain relies on 
two one-way computational technologies: hash functions and digital 
signatures. Most blockchain platforms rely on the elliptic curve public-key 
cryptography or the integer factorization problem to generate a digital 
signature. The security of these algorithms is based on the assumption of 
computational complexity of certain mathematical problems. A universal 
quantum computer would enable efficient solving of these problems, thereby 
making digital signatures, including those used in blockchains, insecure. A 
way to guarantee authentication in the quantum era is to use quantum key 
distribution, which guarantees information-theoretic security based on the 
laws of quantum physics. Quantum key distribution is able to generate a 
secret key between two parties connected by a quantum channel (for 
transmitting quantum states) and a public classical channel (for post 
processing). We discuss a blockchain platform that is based on quantum key 
distribution and review possible experimental realizations for such a 
platform.