qBitcoin – Proposal for a decentralized online quantum cash system

IIAOPSW | 88 points

How does this contribution differentiate from https://arxiv.org/abs/1604.01383? This work just seems way too early + applying quantum-safe crypto to existing Bitcoin ECDSA seems like an easier and more practical solution.

xasos | 7 years ago

What an exciting proposition— if you can use quantum teleportation to solve double-spending, then you don't need mining at all! You don't even need proof-of-stake.

toomim | 7 years ago

It's unclear to me why one might want to use quantum blockchain-based money when there are reasonable proposals for blockchain-free quantum money, e.g. [1].

In any event, I didn't bother reading most of the qBitcoin paper because of things like this:

> First of all, we need to consider how to transmit a coin made of quantum information. The best way, at the present, will be to employ quantum teleportation [2, 3], which succeeds in transforming quantum information to remote places. Great benefit to use the quantum teleportation is that the quantum information cannot remain the original place, in other words, it is impossible for a transmitter to keep the original quantum data once if the quantum information is sent.

This is nonsense. It's like saying that you can transmit a file by mailing a USB stick, which absolutely guarantees that you, the sender, no longer have the original file. That's wrong -- all that mailing a USB stick guarantees is that you don't have the USB stick any more, not that you didn't keep a copy of the contents. Similarly, quantum teleportation eats the input state but says nothing about any other copies of the input state that may exist.

[1] https://arxiv.org/abs/1004.5127 (disclaimer: I'm an author)

amluto | 7 years ago

https://ellcrys.co/

Is using quantum token signature, i'm not sure how different this is from ellcrys.

pixelcloud | 7 years ago

In theory quantum key distribution systems (AKA quantum cryptography) are unbreakable.

In practice they aren't.

See

http://www.qudev.ethz.ch/content/QSIT15/Q_Cryptography_Q_Hac...

https://phys.org/news/2015-12-quantum-cryptography-vulnerabl...

P.S. They describe a property where the money can't be cloned which seems to be further explored in this paper which the author has commented on this thread (see amluto).

https://arxiv.org/pdf/1004.5127.pdf (Quantum Money from Knots) .

zitterbewegung | 7 years ago

I'll take it. It is going to 10x in a few months, right?

vadym909 | 7 years ago

Quantum cash - formalizing the principle that it's impossible to know whether or not you have a dollar until you open your wallet.

maxfurman | 7 years ago

add deep learning and cold fusion in the whitepaper and Im buying

smnplk | 7 years ago

>Making a bock is time consuming and the system of qBitcoin is based on a quantum chain, instead of blocks

A typo in the abstract makes it pretty unlikely that I'll read your proposal.

sigmar | 7 years ago

There is already a coin theqrl.org and significant work is being made on it QRL

arisAlexis | 7 years ago

I feel like this would have better traction if it also used deep learning and were written in Go or Rust.

0xbear | 7 years ago

The hype is real.

aligajani | 7 years ago