Topic: Quantum computing and bitcoin (Read 1962 times)

Where did you get the info? How did they know that it will not be powerful enough, have they tried that already? Or they say that only based on their estimation. They could have tried it first before they came into that conclusion and if they fail on their first try, I do not think they will gave up easily.

We are now in a much modern world so they would have the right tools to create such type of computers but not all are going to have that and its not going to be cheap so not all will have it and use it only to attempt to crack the btc's and I heard devs are now planning to improve the security of btc. They still have the time to do it before the creation of the first quantum computers.

could this theoretically make the owner of the QC a monopoly holder?
with the power of a CQ it seems like bitcoin could be mined exponentially faster, collecting the remaining coins much more efficiently..
what would the impact of this be? would holders of bitcoin benefit from this?

Previously, it was said that quantum computers are unlikely to appear, because they will not be able to reach such a power to crack the security codes of cryptocurrencies. But they have already appeared and their power is growing. A forecast has already been made that at the current rate of improvement of quantum computers, in a maximum of ten years they will be able to hack cryptocurrency wallets.
I don't think we should relax because of the significant amount of time before this event or because such computers will cost a lot of money. Criminals will lay out any amount, just to own them. After all, then in a short time they will be able not only to return their costs, but also to receive much larger amounts. And the predicted time until such an opportunity may also be reduced due to the fact that technologies are also improving.

Without quantum security, our blockchain future is uncertain
DAVID CHAUM(C)
https://cointelegraph.com/news/without-quantum-security-our-blockchain-future-is-uncertain

Two Chinese teams claim to have reached primacy with quantum computers
https://phys.org/news/2021-10-chinese-teams-primacy-quantum.html

Experts are beginning to worry about the impact of quantum computers on internet security and cryptocurrencies.

There is still a long way to go for quantum computing but when it does come of course it will affect bitcoin. Well it will be able to solve algorithms more fast and mining speed would increase, but then again quantum computers would cost alot so its still prettly much balanced so not many miners would but QCs.

Quantum computers are not yet introduced if when to be released but it is just a concept based on researches and knowledge, there is still a lot of time until quantum computers come to being and even if they are introduced they wont be on sale like ordinary computers we use now, maybe only the richest people in the world would be able to buy them.

I tend to disagree. Unlike cold fusion, quantum computing seems to be a real deal. It is not some freak (or fraudster) like Andrea Rossi refusing to reveal how his so called "energy catalyzer" actually works (provided it does work in the first place) who is behind developing quantum computers. Quantum computing has a solid theoretical basis, so it is sort of expected that many national governments and military as well as secret agencies are funding further research into the field. Besides that, it has already been demonstrated that quantum computational operations are in fact possible, though on a relatively small number of quantum bits to make it a real threat for the security of popular cryptographic algorithms in general and the one used for Bitcoin in particular. And it may quite be possible that the research, both practical and theoretical, has advanced much further than we are being told or shown.

QC efficiency vs cpu efficiency has already been solved. bitcoin mining pools.
QC power is not anywhere close to todays hashpower.

also
because QC (in peoples doomsday scenarios) is dealing with solving a binary logic problem. QC becomes limited to the rules of binary logic to ensure it gets an acceptable result in the end. so d-wave cannot work with its 65,536 combinations. it has to stick to 256 combinations to be compatible. because QC has 4 possibilities instead of 2. it allows it to need less bits to solve problems

2 problems at once of base2(byte) instead of just 1 byte in binary
4 problems at once of base16(hex) instead of just 2 hex in binary

ill explain and yes its laymens demonstration, not science whitepaper theory so chill out on knitpicks

imagine a byte 00000000 (8 switches)
and the puzzle is to get a certain Hex(base16) result
in binary, an asic splits the byte in 2. and allows 4 switches(0000) to work on one result and 4 switches(0000) to work on another result
where one can start at 0 (binary0000 all switches off and then incrementally turn them on) and go up to 16
the other starts at 16 (binary1111 all switches on and then incrementally turn them off) and go down to 0

so say you wanted to get hex 9
it would take the first lot of switches 10 attempts (0¹,1²,2³,3⁴,4⁵,5⁶,6⁷,7⁸,8⁹,9¹⁰)
0000(0),0001(1),0010(2),0011(3),00100(4),0101(5),0110(6),0111(7),1000( 8 ),1001(9)
it would take the second lot of switches 7 attempts (F¹,E²,D³,C⁴,B⁵,A⁶,9⁷)
1111(F),1110(E),1101(D),1100(C),1011(B),1010(A),1001(9)

however in QC it wont use 4 switches. as the result it would create once going through all the combinations using its 4 switches would result in a base 256 value when converted to binary.

so QC will use 2 switches to stick to a base 16 puzzle allowing for 4 'chances'. where the efficiency is the
where one can start at 0 (QC 00 all switches off and then incrementally turn them on) and go up to 16(hex:F)
the other starts at 16(hex:F) (QC 33 all switches on and then incrementally turn them off) and go down to 0
the other starts at 7(hex:7) (QC 13 ~half switches on and then incrementally turn them off) and go down to 0
the other starts at 8(hex:8 ) (QC 20 ~half switches on and then incrementally turn rest on) and go upto 16(hex:F)

it would take the forth lot of switches, 2 attempts (8¹,9²)
20( 8 ),21(9)
however QC cannot just send its answer "21" into a binary system. it needs to convert it into binary, which takes resources.

which is like saying
binary:
1.switches show 0(0000) and 16(1111)
2. transmit 00001111 which is 0(0000) and 16(1111) as a whole byte
repeat 6 more times(7 total until there is a correct answer) (7x2=14 processes all together) to get to hex 9

QC:
1.switches shows 0(00) 7(13) 8(20) 16(33)
2.convert 0(00) 7(13) to binary 0(0000) 7(0111)
3.transmit 00000111 which is 0(0000) 7(0111) as a whole byte
4.convert 8(20) 16(33) to binary 8(1000) 16(1111)
5.transmit 10001111 which is 8(1000) 16(1111) as a whole byte
repeat 1 more times(2 total) (2x5=10 processes all together) to get to hex 9

yes there may be some ways to make it efficient. but due to the limits of a 256 combination logic and requirement of conversion. QC is not working at its full potential by solving binary logic problems.

QC will only be fully beneficial in instances that do not even use binary logic problems

yes and no.... drastic changing the algorithm will render the current format of ASICS useless.
imagine an algorithm as a map of a city requiring you to travel the streets. the puzzle is to get to a certain destination.
normal CPU/GPU are not efficient as they need to drive down different streets and allow for other traffic.
an asic is a GPS route planner that knows the route as it is programmed to only follow that route, and there is no other traffic to contend with.
making it super efficient.

if someone changed the puzzle to a completely different town. and ASIC would end up in the wrong place every time
however, there have already been a few optimisations to get to the destination more efficiently without needing to change an asic, but to circumvent QC from a binary system prospective CANT be done effectively without drastic changes, which would effect an asic

however... read on

computers are made using binary logic. and as such a computer cannot be d-wave resistant per-se because a binary(normal) system can only work within its own limits (1 byte=256 possible switch combinations).
Dwave still has 8bits but 4 possibilities(0-1-2-3) per bit bit instead of 2(0-1), allowing for quantum computers(QC) to have 65536 combinations.

however QC cant simply throw its result into a binary system "as is" because the data would get lost in translation(binary:'WTF is a 3?'), it requires QC to calculate a solution, and then convert the result back(like an analogue/digital modem) to binary before a normal computer would understand it. which limits QC capabilities when solving binary logic problems

in short
efficiency due to the limits of binary bytes and logic of such, it only allows d-wave a 2x efficiency at solving binary logic problems and requires translating QC result back to binary result to be accepted by and have impact on binary based systems. (so im not worried)

--Near future would take another 20 years ?
--Bitcoin/Crypto will drastically change in that period if the lightning network changes are deployed.
--Quantum computers will be a real threat to miners since everybody can  mine from their own systems maybe ?
--Will the bitcoin network be able to cope up with the speed at which transactions are processed ?

Yeah it is true, that this is something that becomes our Foundation to stay afloat in the bitcoin. Bitcoin's life will be better, when they could be doing more in-depth research on bitcoin and also use or create devices that support fully about bitcoin. So, just wait for the time to arrive and feel something extraordinary things

Since the topic is centering around Bitcoin, whether we would have to worry about the security of the whole Internet or not is totally irrelevant to the fact that Bitcoin would suffer from SHA becoming insecure. To put it in another way: It's no relief for Bitcoin users, that the Internet is becoming vulnerable as well. So in my eyes this is a non-argument.

For me, it's crystal clear that development must have a plan B well in advance of SHA becoming insecure - regardless if the insecurity comes from quantum computing or some other kind of discovery/invention. We even can't take for granted that there will be clearly visible signs in advance, since most research targeted at breaking encryption happens in secrecy - at three-letter agencies.

Still I don't think that a security threat from Quantum Computing will practically materialize within the next 10 years.

ya.ya.yo!

I just found this one today.

http://www.dwavesys.com/press-releases/d-wave-systems-previews-2000-qubit-quantum-system

So that is not real then or are we missing something? Or maybe the possibility of quantum computers are closer than we thought? The company can be charged with something if they are doing some kind of false advertising for their products, right?

I`m not very familiar with quantum computers.

I don`t know if they will help bitcoin or destroy it.

All i know is that i want a new quantum computer to replace my old PC.

Just kidding.

I agree, and these are the ones we know about.

I am sure there are several generations ahead locked away in secret secure research labs.

it has always been a battle between technology and improvement of security. this has been going on even before computers were created.

people make safes, robbers make drills to open them, safe makers improve the strength of their safe, robbers get better drills, safe makers improve their security with electronic devices, robbers disable the alarms.

we use sha256 for encryption in bitcoin quantum computers become a thing, we move on to a new and more complicated method of encryption, quantum computers 2.0 become a thing we move to encryption 2.0

and this will continue long after you and me are dead

             

Same thought however one day it will happen, I hope the Bitcoin will be ready for this, it's a bilateral progress, we don't have to worry about that. Should we?

First off, this is an awesome explanation (ELI5) of what's going on. I'm not knowledgeable about hardware but that was even easy enough for ME to understand it.

But something people aren't answering WRT changes in algorithm due to faster processing is... ASICs would all be rendered useless, correct? Like aren't ASICs only working with BTC solely because of the current algorithm, such that changing this would render them worthless since they can't be modified? Or is there a way to alter the system in such a way that it's still protected but the current hash power would still be usable? Essentially, I see a huge shift of mining power otherwise, where the first people with quantum ASICs would dwarf all the other hash power combined.

I see a lot of people here are saying that the Algorithm can be upgraded to solve the increase in the processing threat of the introduction of Quantum computers. Has any experiments been done on the Test Net, to see what the impact of such a upgrade would be?

What would be the next possible upgrade? < SHA-384, SHA-512/224 and SHA-512/256 > ? Would this not slow down the network and transactions considerably?