3
$\begingroup$

Could a cryptocurrency running (at least partially) on a quantum computer (and/or on a quantum network) be developed in which it is physically impossible to double-spend? In other words, a coin in which it would be physically impossible to create two transactions that transfer the same coin from one address to two different addresses? Is there any published work on the subject, peer-reviewed or not? For example, if a coin is represented by an uncollapsed quantum state then according to No-cloning theorem it would be physically impossible (or only unlikely?) to transfer said coin to two different recipients, correct?

Edit: accepted the only answer. I don't think it applies here but at least this question shouldn't get deleted automatically...

$\endgroup$

2 Answers 2

5
$\begingroup$

I'm not sure how developed the idea is, but it sounds like you are describing the idea of quantum money.

Also, as it would be a new cryptocurrency, it would not be Bitcoin; Bitcoin is a particular cryptocurrency, and not all cryptocurrencies are Bitcoin in the same way that not all normal currency is US dollars.

$\endgroup$
4
  • $\begingroup$ I'm not sure if this is better as a comment or an answer, so I leaned towards the latter $\endgroup$
    – Ella Rose
    Jan 20, 2018 at 14:43
  • $\begingroup$ I know that it wouldn't be bitcoin but that was the only cryptocurrency related tag I could find. $\endgroup$ Jan 20, 2018 at 18:32
  • $\begingroup$ I found a more recent reference to quantum money but it also fails as a cryptocurrency because it seems to require a central entity with a secret: arxiv.org/abs/0912.3825 $\endgroup$ Jan 20, 2018 at 18:39
  • $\begingroup$ @user1226313 Ah I see, well perhaps we can create a cryptocurrency tag - but first I want to make sure it is on topic for crypto.stackexchange. $\endgroup$
    – Ella Rose
    Jan 20, 2018 at 19:10
1
$\begingroup$

I believe you're talking about quantum money here. While there have been quantum money schemes proposed earlier to prevent double spend, they were all based on ad hoc/nonstandard computational assumptions.

Also, the first explicit construction of quantum money was broken by Andrew Lutomirski et al in 2009. However, there is good news.

A newly published paper presents a quantum algorithm that generates unforgeable money states protected by lattice-based cryptography.

Here's the link Publicly verifiable quantum money from random lattices

I hope this answers your question.

$\endgroup$
1
  • 2
    $\begingroup$ The article is not giving a physical description of what it proposes. What would that be? It's manipulated abstract mathematical objects (points on a lattice), how would they be physically handled? When "mass" pops in, how is that defined? Update: for the later, it could be a probability mass. $\endgroup$
    – fgrieu
    Aug 4, 2022 at 7:31

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.