Questions tagged [cryptocurrency]

A cryptocurrency (or crypto currency) is a digital asset designed to work as a medium of exchange that uses cryptography to secure its transactions, to control the creation of additional units, and to verify the transfer of assets. (Wikipedia) Please be sure that the system under consideration depends crucially on quantum computing.

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Quantum Bitcoin Subdivision

Background Recently I was reading the article "Quantum Bitcoin: An Anonymous and Distributed Currency Secured by the No-Cloning Theorem of Quantum Mechanics" which demonstrates how a quantum bitcoin could function. The article's conclusion states…
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Rigorous security proof for Wiesner's quantum money

In his celebrated paper "Conjugate Coding", Wiesner proposed a scheme for quantum money that is unconditionally impossible to counterfeit, assuming that the issuing bank has access to a giant table of random numbers and that banknotes can be brought…
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Time Entangled Quantum Blockchain

This answer cites a paper[$\dagger$] which purposes a quantum blockchain using entanglement in time. "The weakness is that the research only presents a conceptual design." - QComp2018 How could a quantum blockchain which leverages time entanglement…
user820789
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Are non-secret-based quantum money mini-schemes susceptable to Jogenfors' "reuse attack?"

Aaronson and Christiano call public-key or private-key quantum mini-schemes $\mathcal M$ secret-based if a mint works by first uniformly generating a secret random classical strings $r$, and then generating a banknote $\$:=(s_r,\rho_r)$, where $s_r$…
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Can quantum money be reliably "burned?"

One of the novel features of Bitcoin and other cryptocurrencies is that coins can be irrefutably "burned" or destroyed, by creating a transaction to send the money to a junk burn address. Thinking similarly about quantum money - from knots, or…
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What role do Hecke operators and ideal classes perform in “Quantum Money from Modular Forms?”

Cross-posted on MO The original ideas from the 70's/80's - that begat the [BB84] quantum key distribution - concerned quantum money that is unforgeable by virtue of the no-cloning theorem. A limitation was that the quantum money required the bank…
Mark Spinelli
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How would Blockchain technologies change to survive a post-quantum world?

Reading this entertaining piece of a QC enthusiast mining bitcoins with a Quantum Computer (although efficiently mining bitcoins with the current state of QCs is far-fetched, it is quite possible to be done in the next few years), I wonder how…
nj2237
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Can a merchant who accepts a knot-based quantum coin mint her own knot-based coin?

Referring to Farhi, Gosset, Hassidim, Lutomirski, and Shor's "Quantum Money from Knots," a mint $\mathcal{M}$ generates a run of coins, including, say, $(s,|\$\rangle)$, using a quantum computer to mint $|\$\rangle$ while publishing the public…
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Can we use cryptocurrency mining to verify claims of quantum advantage?

Beginning with the earlier works of work of Brakerski et al. or the more recent results of Kahanamoku-Meyer et al., interactive proofs of quantum advantage entail a classical verifier (Vicky) providing a quantum prover (Peggy) a circuit to evaluate…
Mark Spinelli
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Has Blockchain made Quantum Money obsolete?

Quantum Money is an old proposal that solves the forgeability problem of traditional banknotes, by leveraging the No-Cloning Theorem. Recently, blockchains solved the Double-Spending problem allowing them to be de facto usable as money. Indeed even…
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Will quantum computing kill cryptocurrencies, ecommerce and private communications (Signal, TOR, etc)?

And if a specific country or nation-state gets a breakthrough and keeps quiet about it, can they go about quietly decrypting everything online with us none the wiser and expecting/thinking we're safe? EDIT: A previous question with link was…
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Like blockchains, other than the few quantum algorithms available out there, are quantum computers/algorithms a solution looking for a problem?

Like Distributed Ledger Technologies (DLT) and Blockchain, other than the few quantum algorithms available out there, are quantum computers/algorithms a solution looking for a problem? For one, I am ambivalent - with the scarcity of quantum…
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Entanglement for Byzantine fault problem

In "Proof of Work"-Blockchains, the block is added by the member who first solves a hard problem. That's very expensive. But if all blockchain-members get an entangled dice, that randomly selects one of them, there would be consensus. They all would…