Author

Topic: Google claims breakthrough in Quantum computing (Read 862 times)

legendary
Activity: 4424
Merit: 4794
But if quantum computing actually happens, then won’t regular passwords for bank accounts and emails, etc. be most at risk? I mean, there’s a lot more at risk than just Bitcoin and at least Bitcoin private keys have a bunch of digits.

the temperature needed to measure other measures of atoms is so low dont expect it to be a household computer device.
so it will be large industrial machines renting time to individuals (think cloud services)

quantum cant just break encryption. it can just make bruteforcing more efficient
but dont worry. what takes millions of years in binary computing will still take years in quantum

to put it simple. MD5 is not broke because its been made reversible. its broke because people have 'rainbow tables' that list many combinations thus making it easy to find results.

bitcoins level is sooo dense that to store every keypair would take more storage than available on normal computers. the time to do it is as i said multiple years. then the time to reference each one of those for value..
still makes quantum a time painstaking task.

no one would waste a billion dollar machine to brute force a coin which once doing so will collapse the value to make it not worth doing financially.
things like fiat which are legally endorsed to stay active as they are tied to tax law and minimum wage law keeps fiat as a more active target worth hitting. because fiat is not a one hit wonder but a continual target

and ofcourse theres the business profitable side of asking why waste resources and timme on a possible hit of a few coins. when they can make more money analysing other things. like DNA/science. which can earn them more money...

take elon musts space X he is not wasting money just for the dream of mars. he doing it to charge a fee for his transportation services. he wants to be the spacial taxi service. not a dream maker.

google dont do things for dreams. they want to make money out of it.
why waste years bruteforcing something when they can make money from science grants doing dna/ energy research
sr. member
Activity: 378
Merit: 250
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But if quantum computing actually happens, then won’t regular passwords for bank accounts and emails, etc. be most at risk? I mean, there’s a lot more at risk than just Bitcoin and at least Bitcoin private keys have a bunch of digits.
legendary
Activity: 1904
Merit: 1277
have fun
no point arguing no more.

Agreed - I knew we'd agree on something in the end!
It was still nice having the discussion - thanks!
legendary
Activity: 4424
Merit: 4794
hex is 16.. hex converted to binary is 4 binary bits
this is where you are mistaken. always thinking of the after converted format to binary

you thing hex is just 4.... (facepalm)
ill show you again
hex is not 0123(4)
hex is 0123456789ABCDEF(16)

16 not 4
you are totally not thinking outside the binary box
try to not think of just the binary conversion,
then you can start thinking about the scope of quantum computers and not just its limitation based on when converted to binary

by the way quantum computer hardware is 4 states like binary is 2 states
so hex in binary is (4)2
so hex in quantum is (2)4

anyway, maybe best to just continue with your research and hope one day you get out the binary box to expand your mind to things bigger than 2 options
but for now you seen stuck thinking everything is binary, including hex
sorry but there is no point trying to give you more hints as you admit your not wiling to even google search

have fun
no point arguing no more. your definition of hex shows where your stumbling(limiting yourself to binary)
legendary
Activity: 1904
Merit: 1277
well you can continue with your google search for average joe stuff...
ill continue programming
have fun with your studies, hope you can catch up
You're quite rude, aren't you? I mean consistently, not just as a one-off. I'm not rising to it, though :p
I freely admit I'm not an expert in quantum computing, but I do have a background in theoretical physics, with a sizeable chunk of that being QM, so I have a decent grasp of the quantum side.

by the way google quantum computers quarternary
I don't have to... now you're confusing qubits with qudits. This all started with you saying that qubits have 4 states, which they don't!

qbits have 3 states
qubits actually have 4 states

binary has 2 states
0-1

qubit is base 4 or otherwise known as quarternary logic (as oppose to binary logic)
0  1
  X
2  3



oh and bit is about single object/symbol
you can have binary(2) bit
quarternary(4) bit
hexidecimal(16) bit
This is getting a bit absurd now. Hexadecimal is not 16 bit, it's 4 bit. Why? 24, that's why: 2, 4, 8, 16. You don't need 16 binary digits to encode a hexadecimal. Hex '1' is 0001 in binary. Hex 'F' is 1111.

legendary
Activity: 4424
Merit: 4794
well you can continue with your google search for average joe stuff...
ill continue programming

by the way google quantum computers quarternary

just treat the binary stuff as the translated ready for legacy computer stuff
where as the internal workings of quantum computers that a legacy system cant understand is quaternary

oh and bit is about single object/symbol
you can have binary(2) bit
quarternary(4) bit
hexidecimal(16) bit

have fun with your studies, hope you can catch up
legendary
Activity: 1904
Merit: 1277
research: "4 quantum numbers"
Quote
In quantum mechanics, the principal quantum number (symbolized n) is one of four quantum numbers assigned to all electrons in an atom to describe that electron's state.

I'm familiar with the basic physics. But we are talking about qubits here, not atomic structure.

A qubit is a quantum bit, a quantum binary digit. It holds information on a two-state system. So for example spin could be used, the qubit is in a superposition of 'up' and 'down', and measurement collapses the wavefunction into either 'up' or 'down'. Similarly we could use polarisation, the qubit's polarisation is a superposition of horizontal and vertical, measurement resolves to one of the two values - analagous to 0 or 1.

Your '4' value doesn't refer to 4 discrete outcomes, but to 4 degrees of freedom in an atomic context. There are a lot more than 4 possible combinations of quantum numbers... but this isn't relevant to qubits, because a qubit holds one bit of information (or rather a superposition, but resolves to one bit). Another example: what if your qubit is a photon? You can see how the principal quantum number defining the electron shell is irrelevant here.
legendary
Activity: 4424
Merit: 4794
if you think that qubits are binary(2). then your living in the 1970s only stuck viewing the converted value

maybe try looking into the use of quantum in DNA research
you think you are seeing binary of GTAC being assigned as
g=00        t=01    a=10      c=11
but thats the converted to binary result
in qantum its g=0 t=1 a=2 c=3

now try converting 0123 into binary
oh wait now you see your end result, but idnt see the bit in the middle

super position is mere then just legacy 2 positions
 there are 4
your 00 01 10 11 is just the post-conversion binary representation

right now there is no CPU with a graphic interface that can just accept 0123 as is. so a binary computer needs to be programed in binary and sent it to a quantum processor which converts it to 0123 and then processes it as 0123 and then converts it back to binary for a legacy system to display

its like chinese. an american has to use a translator to speak chinese and then use a translator to convert the chinese response back to american so that the american can then hold a conversation.
in this analogy you are acting as if the chinese guy is speaking american all along. but the truth is the american is only understanding the translator and has no clue whats being spoken in chinese

research: "4 quantum numbers"
Quote
In quantum mechanics, the principal quantum number (symbolized n) is one of four quantum numbers assigned to all electrons in an atom to describe that electron's state.
legendary
Activity: 1904
Merit: 1277
in quantum there is 4
0 is off 1 is 'kinda on' 2 is mostly on and 3 is on
0 is no 1 is maybe  2 is mostly  and 3 is yes
0 is false 1 is false unless  2 is true unless and 3 is true

google has the technology of 4 states and now is trying to code how to use it.
mostly they are dealing with DNA you know GTAC annd having fun with that as binary systems aint good at 4 state things in a 2 state limiting system


It's a superposition of 0 and 1. It's a continuum, an infinite number of possible values... but based on a superposition of 2 classical outcomes. A single qubit can only yield 0 or 1.

Can you give me a link to this '4 state' outcome stuff? I'm sure there is a misunderstanding somewhere. You get 4 possible outcomes from a 2 qubit system(22), but 1 qubit can only give you 0 or 1. Google I think did 53 qubits, so 253, or 9007199254740992 outcomes.
legendary
Activity: 4424
Merit: 4794
its 0123 no 01.

There are only 2 states contributing to the superposition, 0 and 1.

You mean 4 because the probability amplitudes are complex numbers and each have 2 degrees of freedom? So 2x2 =4? ... But probability is amplitude squared (the Born rule)... so we are back to 2.

nope i mean X not -
4 edges not 2
the 2 states with 2 possible answer is the result after quantum converts back to binary
it gives 2 answers in binary

what your not realising is your still thinking logical 2 state

in quantum there is 4
0 is off 1 is 'kinda on' 2 is mostly on and 3 is on
0 is no 1 is maybe  2 is mostly  and 3 is yes
0 is false 1 is false unless  2 is true unless and 3 is true

google has the technology of 4 states and now is trying to code how to use it.
mostly they are dealing with DNA you know GTAC annd having fun with that as binary systems aint good at 4 state things in a 2 state limiting system
legendary
Activity: 1904
Merit: 1277
its 0123 no 01.

There are only 2 states contributing to the superposition, 0 and 1.

You mean 4 because the probability amplitudes are complex numbers and each have 2 degrees of freedom? So 2x2 =4? ... But probability is amplitude squared (the Born rule)... so we are back to 2.
legendary
Activity: 4424
Merit: 4794
qbits have 3 states

qubits actually have 4 states

binary has 2 states
0-1

qubit is base 4 or otherwise known as quarternary logic (as oppose to binary logic)
0  1
  X
2  3

Not really. It's still just 1s and 0s in quantum computing - the difference is superposition, the fact that in QC multiple states exist simultaneously. So as you increase the number of qubits (x), the processing power increases exponentially, 2x.

your funny, but appears your still reading the fluff 2016 media stuff
try actually reading the proper technical stuff and you know maybe try programming some

its 0123 no 01. it requires then a converter to turn the 0123 into 0,1 for logical computers to understand. which lays in  afew concerns at the moment as not all quantum results can translate into binary results that solve the binary problem trying to be solved.


but hey it will take you a while to get to program a quantum system, so have fun unwrapping the myths of multidimensional blackholes being part of it. (tip: its not about sci-fi stuff)
or maybe just realise the real answer that super position and multidimensional means 'more' positions and 'more' dimensions.. as in more then 2, meaning 4 and more than 2d meaning 3d

its not sci-fi its just moving from 2 to 4.
its like replacing a light switch for a light dimmer that has more brightness options.
not some entrance to other worlds of dopplegangers

if you look at a binary system of 8bits its like 0-0-0-0-0-0-0-0
where to light up all 8 requires 11111111
if you look at a quantum system its like
0 0 0 0
 X X X
0 0 0 0
where to light up all 8 requires 3 3 3

oh and here is a picture on the left that might help

(hint: no wormholes in sight)
(hint: no - but yes: x)

have a nice day
legendary
Activity: 1904
Merit: 1277
Honestly, I figured breaking mining would break bitcoin more effectively than hacking addresses.

Mining is certainly vulnerable, but it's not the weakest point.
I had a try at summarising this a while ago on another thread...

Hi all  Smiley I thought I’d try to summarise Bitcoin's vulnerabilities to Quantum Computers, as well as some potential defences, and get it all in one post. Apologies for the wall of text, but hopefully it is useful...


Mining can potentially be much quicker with QCs.
The current PoW difficulty system can be exploited by a Quantum Computer using Grover’s algorithm to drastically reduce the number of computational steps required to solve the problem. The theorised advantage that a quantum computer (or parallelised QCs) have over classical computers is a couple of orders of magnitude, so ~x100 easier to mine. This isn’t necessarily a game-changer, as this QC speed advantage is likely to be some years away, by which time classical computers will surely have increased speed to reduce the QC advantage significantly. It is worth remembering that QCs aren’t going up against run-of-the-mill standard equipment here, but rather against the very fast ASICs that have been set up specifically for mining.

Re-used BTC addresses are 100% vulnerable to QCs.
Address Re-Use. Simply, any address that is re-used is 100% vulnerable because a QC can use Shor’s algorithm to break public-key cryptography. This is a quantum algorithm designed specifically to solve for prime factors. As with Grover’s algorithm, the key is in dramatically reducing the number of computational steps required to solve the problem. The upshot is that for any known public key, a QC can use Shor’s approach to derive the private key. The vulnerability cannot be overstated here. Any re-used address is utterly insecure.

Processed (accepted) transactions are theoretically somewhat vulnerable to QCs.
Theoretically possible because the QC can derive private keys from used addresses. In practice however processed transactions are likely to be quite secure as QCs would need to out-hash the network to double spend.

Unprocessed (pending) transactions are extremely vulnerable to QCs.
As above, a QC can derive a private key from a public key. So for any unprocessed transaction, a QC attacker can obtain the private key and then create their own transaction whilst offering a much higher fee, so that the attacker’s transaction gets onto the blockchain first, ahead of the genuine transaction. So block interval and QC speed are both crucial here – it all depends on whether or not the a QC can hack the key more quickly than the block is processed.


Possible defences...

Defences using classical computers.
  • Modify the PoW system such that QCs don’t have any advantage over classical computers. Defending PoW is not as important as defending signatures (as above), because PoW is less vulnerable. However various approaches that can protect PoW against QCs are under development, such as Cuckoo Cycle, Momentum and Equihash.
  • Modify the signature system to prevent easy derivation of private keys. Again, various approaches are under development, which use some pretty esoteric maths. There are hash-based approaches such as XMSS and SPHINCS, but more promising (as far as I can tell) are the lattice-based approaches such as Dilithium, which I think is already used by Komodo.

Defences using quantum computers.
As I’ve said a few times, I’m more of a bumbling enthusiast than an expert, but exploiting quantum properties to defend against QC attack seems to me a very good idea. In theory properties such as entanglement and the uncertainty principle can offer an unbreakable defence. Again, people are busy researching this area. There are some quite astonishing ideas out there, such as this one.


I’ll leave it there. Apologies for all the external links, but hopefully this has summarised a few things.

legendary
Activity: 1904
Merit: 1277
qbits have 3 states

qubits actually have 4 states

binary has 2 states
0-1

qubit is base 4 or otherwise known as quarternary logic (as oppose to binary logic)
0  1
  X
2  3

Not really. It's still just 1s and 0s in quantum computing - the difference is superposition, the fact that in QC multiple states exist simultaneously. So as you increase the number of qubits (x), the processing power increases exponentially, 2x.

With a single bit, a classical computer can be 0 or 1, but a single qubit can be 0 and 1... 2 states simultaneously.
With 2 bits, a classical computer can be 00, 01, 10 or 11... but still only processing sequentially, one outcome at a time... whereas a 2 qubit QC can be 00, 01, 10 and 11 simultaneously, so (crudely) analogous to 4 classical computers running at the same time.
With 3 bits, 8 possible states for a classical computer to process sequentially... and 8 (i.e., 23) states for a QC to process simultaneously, like 8 classical computers running at the same time... etc.

It's this ability of QCs to try multiple paths simultaneously that makes them so good for problems like factoring. It doesn't mean they are hugely faster than classical computers for every task, but for certain specialised tasks a QC can turn the almost-impossible into the trivial.

Have a look at this thread if you're interested in QC - my favourite thread on the forum! We've been having an interesting and quite in-depth discussion!
legendary
Activity: 4424
Merit: 4794
qbits have 3 states

qubits actually have 4 states

binary has 2 states
0-1

qubit is base 4 or otherwise known as quarternary logic (as oppose to binary logic)
0  1
  X
2  3
full member
Activity: 840
Merit: 128
Don't worry about.
If they have a working quantum computer they would keep it secret in order to use in case of war.
There are more important uses than using it for breaking BTC.
Do you remember what happened with enigma?
Alan Turing and his team constructed a machine that broke the codes made by enigma.
None new about it, this construction was revealed more then 30 years later in the '70s.

Bitcoin in danger?

Quote
This week, news has emerged that Google has made a recent quantum computing breakthrough, achieving quantum supremacy. It is being reported that Google, using a quantum computer, managed to perform a calculation in just over three minutes that would take the world's most powerful supercomputer 10,000 years.
...

According to Gizmodo, it has been long known that Google has been testing a 72-qubit device called Bristlecone with which it hoped to achieve quantum supremacy and the initial report from the Financial Times says that the supremacy experiment was instead performed with a 53-qubit processor codenamed Sycamore.

...

"Blockchains won't be ready for such a breakthrough. Since transaction history is the backbone of blockchains, such an improvement in quantum computing could be catastrophic for the whole transaction history," added the CTO. "There is an extra layer of protection with Bitcoin's double hashing but assuming a quantum computer is capable of Shor on secp256k1 it's safe to assume it's also capable of Grover256. Also, we don't know bounds for SHA regarding quantum circuits."
...


https://www.forbes.com/sites/darrynpollock/2019/09/24/googles-quantum-computing-breakthrough-brings-blockchain-resistance-into-the-spotlight-again/
legendary
Activity: 2394
Merit: 1632
Do not die for Putin

Did you mean complexity of 2^128, as that is the complexity of cracking bitcoin with the best known non QC algorithm. And QC could not use that algorithm, so it would probably need the full 256 qubits to do the calculations.

...

I understood it with the first video on the thread. It seems that quantum computing is particularly effective at computing many states simultaneously and that is as well quite effective to break SHA crypto.
legendary
Activity: 1512
Merit: 1218
Change is in your hands
full member
Activity: 378
Merit: 197
I thought it broke at a complexity of 128^3 from what was previously discussed last time (I have no links though). Isn't this old news? I'm sure we saw the same headline about 6 months ago...

Forbes and the financial Times seem really awful sources nowadays, perhaps their editor bought stocks in Google or something..., There seemed to be a consensus that the sha256 hashing algorithm was quantum proof too - people don't want to act until the nsa release standards of quantum proof encryption so we're stuck in the hope that's the case anyway...
Sorry if I understood wrongly, but:
Did you mean complexity of 2^128, as that is the complexity of cracking bitcoin with the best known non QC algorithm. And QC could not use that algorithm, so it would probably need the full 256 qubits to do the calculations.

As adding more qubits to a QC gets exponentially harder, I do not believe we will see a true 256 qubit QC for a long looong time, if ever.

According to what I have read about the subject, sha256 is not vulnerable to quantum computers.

There are many people, who do not trust NSA any longer, so I wouldn't be so sure that bitcoin would move to their quantum "proof" standard when they publish one Smiley
legendary
Activity: 2394
Merit: 1632
Do not die for Putin

... I figured breaking mining would break bitcoin more effectively than hacking addresses.

If you hack mining the benefit is not that much and it will likely be detected. However, if you break a key it would be blamed on the owner for "not securing it".
copper member
Activity: 2856
Merit: 3071
https://bit.ly/387FXHi lightning theory
https://youtu.be/lvTqbM5Dq4Q

This explains why the encryption algorithmm bitcoin uses will be insecure. It looks at rsa encryption and ecc is generally considered more secure but only by a magnitude of about 1024-256 (afaik but it was a long time since that module).



I think the thing with mining is that quantum computers will advance at the same rate so there'll still be competition between the miners and it won't be too difficult to turn sha256 into a 2048 bit bash or higher to keep advancing the algorithm (it's just a few OR operations anyway) - the affect of a new machine will probably be the current affect of bitmain making a new miner.

This explains sha better: https://youtu.be/DMtFhACPnTY
legendary
Activity: 2394
Merit: 1632
Do not die for Putin

Sha256... I guess it'd be the entropy of the hash. I just assumed sha256 had 256 bits of entropy. That's probably a horrible assumption considering the 256 is the digest.

qbits have 3 states

I thought it broke at a complexity of 128^3 from what was previously discussed last time...

Forbes and the financial Times seem really awful sources nowadays, ...

I do not understand clearly your point. For me it would be a question on how long would it take to break a key, so it would have to be measured in terms of the speed at which a key can be broken.

RE hype and such, of course, there is, but no, the news are recent.
full member
Activity: 574
Merit: 152
Wouldn't a quantum computer need 256 qubits to break bitcoin?

Also, if there's a strange amount of blocks being mined by a new entity, can't we just fork with a new algorithm (and fuck over ASIC manufacturers at the same time Wink)

Where do you get that number from? Just curious.

Is not about blocks mined, is about keys broken. Full collapse, hard fork, market stop...

Sha256... I guess it'd be the entropy of the hash. I just assumed sha256 had 256 bits of entropy. That's probably a horrible assumption considering the 256 is the digest.

Honestly, I figured breaking mining would break bitcoin more effectively than hacking addresses.
copper member
Activity: 2856
Merit: 3071
https://bit.ly/387FXHi lightning theory
I thought it broke at a complexity of 128^3 from what was previously discussed last time (I have no links though). Isn't this old news? I'm sure we saw the same headline about 6 months ago...

Forbes and the financial Times seem really awful sources nowadays, perhaps their editor bought stocks in Google or something..., There seemed to be a consensus that the sha256 hashing algorithm was quantum proof too - people don't want to act until the nsa release standards of quantum proof encryption so we're stuck in the hope that's the case anyway...
legendary
Activity: 2394
Merit: 1632
Do not die for Putin
Wouldn't a quantum computer need 256 qubits to break bitcoin?

Also, if there's a strange amount of blocks being mined by a new entity, can't we just fork with a new algorithm (and fuck over ASIC manufacturers at the same time Wink)

Where do you get that number from? Just curious.

Is not about blocks mined, is about keys broken. Full collapse, hard fork, market stop...
full member
Activity: 574
Merit: 152
Wouldn't a quantum computer need 256 qubits to break bitcoin?

Also, if there's a strange amount of blocks being mined by a new entity, can't we just fork with a new algorithm (and fuck over ASIC manufacturers at the same time Wink)
legendary
Activity: 2394
Merit: 1632
Do not die for Putin
Bitcoin in danger?

Quote
This week, news has emerged that Google has made a recent quantum computing breakthrough, achieving quantum supremacy. It is being reported that Google, using a quantum computer, managed to perform a calculation in just over three minutes that would take the world's most powerful supercomputer 10,000 years.
...

According to Gizmodo, it has been long known that Google has been testing a 72-qubit device called Bristlecone with which it hoped to achieve quantum supremacy and the initial report from the Financial Times says that the supremacy experiment was instead performed with a 53-qubit processor codenamed Sycamore.

...

"Blockchains won't be ready for such a breakthrough. Since transaction history is the backbone of blockchains, such an improvement in quantum computing could be catastrophic for the whole transaction history," added the CTO. "There is an extra layer of protection with Bitcoin's double hashing but assuming a quantum computer is capable of Shor on secp256k1 it's safe to assume it's also capable of Grover256. Also, we don't know bounds for SHA regarding quantum circuits."
...


https://www.forbes.com/sites/darrynpollock/2019/09/24/googles-quantum-computing-breakthrough-brings-blockchain-resistance-into-the-spotlight-again/
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