Tutorial on
Quantum Computing Essentials for Financial Cryptographers
2022

In Association with Financial Cryptography 2022

May 6, 2022

Radisson Grenada Beach Resort
Grenada

Schedule

• Introduction to quantum computing:

  We will begin by learning the basic concepts of quantum computing and the fundamental quantum algorithms that would be essential for the rest of the talks.

  References: Nielsen and Chuang Book; No-cloning theorem; Grover's search algorithm; Shor's Factoring Algorithm.

• Effects of Quantum Computing on Bitcoin:

  We will discuss how a quantum computer can steal bitcoins by breaking the digital signatures currently used in Bitcoin; which are the bitcoins that are most unsafe; how we can migrate bitcoins to addresses with post-quantum digital signatures as well as the challenges associated with it, and the challenges in using the currently available post-quantum digital signatures for Bitcoin. We will also discuss how the strategy space for Bitcoin mining changes in the presence of a quantum computer and analyze the complications that arise as a result. In particular, we will see quantum strategies that can increase the fork rate of the blockchain which we know is a security threat to Bitcoin.

  References: [SAT'20]; [LRS'19]; [BL'95]; [IKK'20];[SIZ+'18]; [NG'21].

• Private quantum money:

  We will study the most basic form of quantum money called private quantum money and its various forms. We will discuss the Wiesner's money scheme and its different variants, which are arguable the simplest constructions of quantum money, and analyze how it can be a potential alternative to traditional monetary systems in the future.

  References: Wiesner's money; Classically Verifiable Variants of Wiesner's money: [PYJ+'12,MVW'13]; Semi-quantum money; Quantum coins: [MS'10, JLS'18, BS'19, BS'20].

• Public quantum money and additional advanced topics:

  In this last talk, we will discuss and see some of the constructions of public quantum money which is a more sophisticated variant of quantum money with more desirable properties comparable to that of cryptocurrencies. We will also explore in brief other related quantum cryptographic primitives, which can provide alternative solutions for problems related to cryptocurrencies, such as the blockchain scalability problem.

  References: Aaronson-Christiano and Zhandry public quantum money constructions; Tokens for Digital Signatures and also see [BSS'20]; Quantum Lighting; One-shot Signatures; and Hybrid Blockchains.

Location: Trinidad Room.