Why is Bitcoin safe against a quantum computer?

[tkbx]

Quantum computers are just a theoreticall concept

We can't rely on a piece of technology not being created to keep out coins safe. Imagine if bitcoin hadn't grown at this rate, $500 of ASIC could have done a 51%

By the way, I love how your address has QR in it, and vice versa

[sgravina]

I just read this thread up to this point.  It is almost all nonsense.  The capabilities of quantum computers have been describe well in other forum topics.

Bottom line:  Quantum computers can't do anything, except this: 15 = 3 * 5;

[Mike Christ]

I just read this thread up to this point.  It is almost all nonsense.  The capabilities of quantum computes have been describe well in other forum topics.

Bottom line:  Quantum computers can't do anything, except this: 15 = 3 * 5;

So it does computations...backwards

[Raoul Duke]

I just read this thread up to this point.  It is almost all nonsense.  The capabilities of quantum computes have been describe well in other forum topics.

Bottom line:  Quantum computers can't do anything, except this: 15 = 3 * 5;

What a bad quantum computer would that be.
Everyone knows the optimal way to get 15 is 15*1, not 3*5

[Come-from-Beyond]

Neither is every public private keypair in the world, by your logic. So don't do online banking. Or shop online. Or do credit card transactions.
Bitcoin is not the only thing not safe from the concept.

Why does CIA need to destroy the banking system?

Why do you assume the CIA will control a quantum computer initially, assuming it is invented and practically usable?

Shouldn't we be ready for the worst case scenario when the CIA controls a QC initially?

Neither is every public private keypair in the world, by your logic. So don't do online banking. Or shop online. Or do credit card transactions.
Bitcoin is not the only thing not safe from the concept.

Why does CIA need to destroy the banking system?

OK, I'll play your game.

Why does CIA need to destroy the Bitcoin network?

Shouldn't we be ready for the worst case scenario when the CIA needs to destroy the Bitcoin network?

Neither is every public private keypair in the world, by your logic. So don't do online banking. Or shop online. Or do credit card transactions.
Bitcoin is not the only thing not safe from the concept.

Why does CIA need to destroy the banking system?

The point is that if Bitcoin's algorithm can be broken then there will be more profitable targets than Bitcoin.

Shouldn't we be ready for the worst best case scenario when Bitcoin is the most profitable target?

I just read this thread up to this point.  It is almost all nonsense.  The capabilities of quantum computers have been describe well in other forum topics.

Bottom line:  Quantum computers can't do anything, except this: 15 = 3 * 5;

Shouldn't we be ready for the worst case scenario when a QC, that is able to break Bitcoin, appears in a few years?


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Well guys. I see that most of you just hope that Bitcoin won't be broken and there is no REAL protection against an attack, described in the original post.

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[markm]

I do not really consider the purported capabilities of so called quantum computers really well "proven", actually, in the light of Harmony Christian's work.

Because if he is correct that the so called "spooky" stuff is simply the failure of a generation or few of physicists to account the topology of the units correctly in Bell's (and similar) inequalities, resulting in surprise when the 7-sphere topology bit them for forgetting about it / dismissing it as irrelevant, there might not actually be anything spooky going on at all, and the failure to factor anything larger than 15 might simply be because 15 is trivial enough it doesn't really actually require anything "spooky" to factor it.

-MarkM-

[markm]

If Christian is right, then classical computing should be able to reproduce all the results so called "quantum computing" can achieve, although how much slower it would be to do it that way I don't know.

Furthermore, he even has an experiment one can do with macroscopic balls that, if he is right, should reproduce the "spooky" results on the macroscopic scale, thus demonstrating they are simply the topology of space, applicable at all scales, not some special weirdness down where things get small enough to introduce measurement uncertainties and such.

Unfortunately, as far as I have heard so far, no one has actually built the little plastic balls prescribed and run the actual experiment yet. Partly it seems everyone is so sure the universe is fundamentally spooky that no one can be arsed to actually check whether, in fact, it actually is.

Basically it is classical geometry of the n-sphere and/or classical topology of the n-sphere kind of stuff, best represented using Clifford algebras, but even those who purport to be familiar with Clifford algebras don't really seem to be particularly handy with them.

He presents it in other notations too but his detractors tend to keep shooting him down inventing weird glitches almost as oopsie as the one Bell started his theorem / inequalities paper with that Christian is attempting to elucidate.

-MarkM-

[Come-from-Beyond]

Basically it is classical geometry of the n-sphere and/or classical topology of the n-sphere kind of stuff, best represented using Clifford algebras...

The best explanation for 8 yo ever!

[mobile4ever]

Wouldnt stronger cryptography fix that?

[Come-from-Beyond]

Wouldnt stronger cryptography fix that?

It will. But we should start doing ANYTHING except praying to Satoshi.

[surebet]

ITT

[mokahless]

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Well guys. I see that most of you just hope that Bitcoin won't be broken and there is no REAL protection against an attack, described in the original post.

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If a malicious individual gets a hold of a single computer capable of that kind of speed, I think Bitcoin will be the least of our worries.

On a side note, I just found a bunch of interesting material that might answer all the OP's questions though I cannot say for sure since I have not read the material myself yet.
https://bitcointalk.org/index.php?topic=133425.0
http://www.cs.virginia.edu/~robins/The_Limits_of_Quantum_Computers.pdf
https://www.google.ca/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&cad=rja&ved=0CDoQFjAB&url=http%3A%2F%2Fwww.springer.com%2Fcda%2Fcontent%2Fdocument%2Fcda_downloaddocument%2F9783540887010-c1.pdf%3FSGWID%3D0-0-45-645102-p173864247&ei=3IdGUc-lI4muyQG554CIBA&usg=AFQjCNElz3JULn_Aa1H6NolkLNb9tbuX_g&sig2=0uHjvbW2jIBxRwMP7VIySg&bvm=bv.43828540,d.aWc

EDIT: I believe my third link has all answers.

So in summary: ESDSA would be broken and SHA256 would be fine.

[markm]

If Qubits really can solve such problems and Christian is right maybe we can solve them on GPUs using Octonians.

-MarkM-

[Bitcoinpro]

it would have be a quantum asic to have the desired effects, not enough zeros on the processor speed will be added imo

[markm]

It still seems possible to me that quantum computing cannot really solve stuff the way it likes to claim.

This is because the claims are based on hypothetical spookiness. If really there is no spookiness, just plain old classical geometry of the 7-or-less sphere, once you have gone around the sphere a couple of times (a "double cover") maybe that is all you get, since going around more times still leaves you at a point of that same kind of sphere, and if the cover is only a double cover you only get two "different kinds" of "being there", you're either there with a twist or there without a twist, kind of thing, any larger number of twists unravels into one twist or none.

15 = 3 x 5 only involves the second prime, if you allow 1 to count as the zeroeth prime and 2 as the first prime. I'd like to see at least one more prime get solved otherwise maybe we can only solve for an untwisted case, say, 2 and a twisted case, say 3, and all the rest ahead might just unravel into one of those two cases, blowing all the wonderful quantum algorithms that all think quantum is some spooky thing not just simple geometry / topology of n-spheres.

-MarkM-

[Rincewind]

Setting aside the fallacious leap that quantum computing would be a magic bullet, I would really be interested to hear some peoples' reasoning for WHY the government (CIA) would want to kill bitcoin in the first place? Seems so many people think its a foregone conclusion that if BTC gets big, the Fed will look to kill it. Is that really true?

If the US State Department is directly funding subversive and disruptive technologies such as Tor for the benefit of pro-dem activists in China and the Middle East, it stands to reason that the State Dept would also find Bitcoin beneficial, as it allows them an avenue to fund disruptive activism without the finger falling back on the POTUS.

I don't think you can reconcile an attack against the one truism of BTC, the best use of superior computational power will always be to 'print your own money.'

[markm]

Even if quantum does work, it isn't useful for hashing.

So all those SA goons with quantum computers in their mother's basement aren't going to be able to use them for hashing, thus to make money the mining way, they'll have to find other ways to put their toys to use. Such as by breaking all kinds of crypto all over the world, much of which might be even more profitable than hacking bitcoin txouts.

-MarkM-

[Come-from-Beyond]

...I would really be interested to hear some peoples' reasoning for WHY the government (CIA) would want to kill bitcoin in the first place? Seems so many people think its a foregone conclusion that if BTC gets big, the Fed will look to kill it. Is that really true?

"Give me control of a nation's money and I care not who makes it's laws." (c) Rockefeller

If the US State Department is directly funding subversive and disruptive technologies such as Tor for the benefit of pro-dem activists in China and the Middle East...

They are funding Tor to be able to use it by themselves. They disguise activity of their agents who use Tor making appearance they are ordinary hackers.

[mobile4ever]

They are funding Tor to be able to use it by themselves. They disguise activity of their agents who use Tor making appearance they are ordinary hackers.

The feds made Tor... so sure why not?

[Qoheleth]

Bitcoin has some protections against a quantum computer, although not enough.

The thing about addresses is that they aren't cleartext public keys - they're hashes thereof, which for quantum computers are only slightly less infeasible to brute-force.

So the good news is that until you spend from a particular address, your coins at that address are safe; if you avoid reusing addresses, and if you always empty them out when you spend them, and if you submit your transactions directly to the big pools, the risk of someone stealing your coins with a quantum computer is low (because even if they cracked your private key, stealing the coins would effectively require them to double-spend against you).

Really, a quantum-resistant signature scheme would be ideal, but they all have a digest+public key size in the kilobytes (which would require significant, possibly infeasible, block size increases). Hopefully, as the state of the art advances, a more succinct post-quantum signature algorithm will be found that can be easily rolled into Bitcoin.