Topic: Are quantum computers closer to becoming reality? (Read 1373 times)
quantum computers are closer to reality than we know ,our computers are already quantum but with different concepts .if we use different concepts we will get we want and concepts can develop with time and mature so every thing can happen i believe in one concept the media .
Quantum Computing is Science-Fiction and nothing else! One value cannot be two values simultaneously (or switch between the two)! It defies all logic, observable reality and deep down you all know it!
Just because you don't believe it is possible and can't get your mind around the extremely difficult concepts of quantum physics does not mean that it is impossible. Not only have quantum computers been made (low qubit, but still QCs), but the quantum behavior has also been observed. IBM has been doing a lot of research into Quantum Computers and have also made a 5 qubit QC which people can use.
This is not an easy question. I take it to mean, how far are we from a scalable universal quantum computer? Fifteen years ago we were about ten years from a working scalable universal quantum computer. The field hasn't been standing still. There are many very promising qubits standards, but all seem to have at least one technical obstacle. There are very good designs for error correcting logical qubits that require anywhere up to 20 ancilla qubits per logical qubit. So far no hardware implementation has reached the point where the appropriate architectures can be fabricated. However, with the likes of Google, IBM, HP and many top universities on board, I would hope that some working scalable universal quantum computer will be demonstrated within the next 10 years. I think that superconducting circuits may be the first across the line, although I'd like to see some kind of photonic/solid-state hybrid that runs at room temperature.
let's suppose quantum computing is available, let's say it is powerful, let's say NSA have a problem with bitcoin and owns a bunch of them.
If they break double sha256, can't bitcoin core move to annother algo ?
Can the sollution be as simple ?
Let's say that we are still far from quantum computing, how about it ? Think about this MIT post : http://news.mit.edu/2015/optoelectronic-microprocessors-chip-manufacturing-1223
Maybe Bitcoin will have to face both threats : http://newatlas.com/photonic-quantum-computer-chip/38928/
This will be an issue in no time : http://www.engineering.com/ElectronicsDesign/ElectronicsDesignArticles/ArticleID/13508/Protoype-Photonic-Chip-Shines-a-Light-on-Practical-Quantum-Computing.aspx
Regarding these articles, i think the community's questions are legit.
If they break double sha256, can't bitcoin core move to annother algo ?
Can the sollution be as simple ?
Let's say that we are still far from quantum computing, how about it ? Think about this MIT post : http://news.mit.edu/2015/optoelectronic-microprocessors-chip-manufacturing-1223
Maybe Bitcoin will have to face both threats : http://newatlas.com/photonic-quantum-computer-chip/38928/
This will be an issue in no time : http://www.engineering.com/ElectronicsDesign/ElectronicsDesignArticles/ArticleID/13508/Protoype-Photonic-Chip-Shines-a-Light-on-Practical-Quantum-Computing.aspx
Regarding these articles, i think the community's questions are legit.
If you think that bitcoin is in danger because of this invention, than I can't agree you because goverments have powerful quantum computers, there is no doubt. Also there are many talented hackers and nowdays no one was able to damage bitcoin system. I don't say that there is nothing impossible but technologies are developing, so that means bitcoin will be developed if there is need.
Wasn't the SHA1 collision limited to PDF documents?
I only quickly read the statement, will have to re-read the document more carefully.
The attack was done on PDF files because that was the easiest to do that makes the collision obvious (clear visual difference, same hash). However, they have shown that it is possible to produce a SHA1 collision in general (a PDF is just a bunch of bytes of data, just like any other piece of data).I only quickly read the statement, will have to re-read the document more carefully.
Anyways, if someone is able to crack SHA256, they will be using that technology for something larger than bitcoin.
We are talking national security type stuff here: breaking into government systems and decrypting top-secret documents.
The problem is not that QCs can break SHA256 (and they really can't) but rather QCs that can break ECDSA. If someone can get the private key out of a public key, then Bitcoin will need to stop using ECDSA.We are talking national security type stuff here: breaking into government systems and decrypting top-secret documents.
Quantum Computing is Science-Fiction and nothing else! One value cannot be two values simultaneously (or switch between the two)! It defies all logic, observable reality and deep down you all know it!
Just because you don't believe it is possible and can't get your mind around the extremely difficult concepts of quantum physics does not mean that it is impossible. Not only have quantum computers been made (low qubit, but still QCs), but the quantum behavior has also been observed. IBM has been doing a lot of research into Quantum Computers and have also made a 5 qubit QC which people can use. 
Wasn't the SHA1 collision limited to PDF documents?
I only quickly read the statement, will have to re-read the document more carefully.
Anyways, if someone is able to crack SHA256, they will be using that technology for something larger than bitcoin.
We are talking national security type stuff here: breaking into government systems and decrypting top-secret documents.
I only quickly read the statement, will have to re-read the document more carefully.
Anyways, if someone is able to crack SHA256, they will be using that technology for something larger than bitcoin.
We are talking national security type stuff here: breaking into government systems and decrypting top-secret documents.
Quantum Computing is Science-Fiction and nothing else! One value cannot be two values simultaneously (or switch between the two)! It defies all logic, observable reality and deep down you all know it!
From what i've read, SHA256 will make bitcoin safe for the rest of our lifetimes... this makes me calm enough. Beyond that, as far as I know, PoW algo can be changed into another algo to make it quantum resistant + additional improvements that will come overtime.
SHA1 was "cracked" recently, I doubt they can crack SHA256 anytime soon.
SHA1 was "cracked" recently, I doubt they can crack SHA256 anytime soon.
The stated conceptualization is incomplete.
Afaik, quantum computing isn't that effective against cracking (finding the preimage of) cryptographic hash functions (afair D.Berstein even argued in a paper that on a theoretical cost basis they don't attain any advantage relative to building crackers with huge RAM). IOTA's whitepaper argues that hash-based PoW and the finality of the longest chain is vulnerable to attack (if Berstein's point is dismissed). Berstein also goes into more detail on the vulnerability of hash functions in his book on Post-Quantum Cryptography (you can google a PDF online).
Rather it is the elliptic curve cryptography (any math theoretic cryptography based on the difficulty of factoring) that is theoretically vulnerable to Shor's algorithm. The SHA256 obscures each public key until it is spent for the current Bitcoin design, but when it is spent then it is temporarily vulnerable until the spend is recorded in the blockchain (but this time window may be insufficient for cracking it with Shor's if the quantum computer isn't powerful enough). However I believe other designs such as MimbleWimble may not have this SHA256 protection?
Do core devs not comment any more in this forum? Gmaxwell?
From what i've read, SHA256 will make bitcoin safe for the rest of our lifetimes... this makes me calm enough. Beyond that, as far as I know, PoW algo can be changed into another algo to make it quantum resistant + additional improvements that will come overtime.
SHA1 was "cracked" recently, I doubt they can crack SHA256 anytime soon.
SHA1 was "cracked" recently, I doubt they can crack SHA256 anytime soon.
As the last paragraph in the article I linked to states, DWave's systems are not 'universal' computers. They can only be applied to some specialized computations and thus I (ignorantly) presume they are inapplicable to Shor's algorithm thus no impact on cryptography.
Not everybody even agree D-Wave makes quantum computers so I think we're safe for now
It's only 50 Qubits, nothing revolutionary. But just like those football stadium sized computers of the old, this is a step forward to something greater. (Plz don't break SHA256)
Any reactions about the following?
https://www.scientificamerican.com/article/ibm-will-unleash-commercial-universal-quantum-computers-this-year/
What impacts does this have on Bitcoin and other technologies such as Confidential Transactions, MimbleWimble, etc?
https://www.scientificamerican.com/article/ibm-will-unleash-commercial-universal-quantum-computers-this-year/
What impacts does this have on Bitcoin and other technologies such as Confidential Transactions, MimbleWimble, etc?
Welcome to the Future
Quantum Computing for the Real World Today
https://www.dwavesys.com/
Any reactions about the following?
https://www.scientificamerican.com/article/ibm-will-unleash-commercial-universal-quantum-computers-this-year/
What impacts does this have on Bitcoin and other technologies such as Confidential Transactions, MimbleWimble, etc?
https://www.scientificamerican.com/article/ibm-will-unleash-commercial-universal-quantum-computers-this-year/
What impacts does this have on Bitcoin and other technologies such as Confidential Transactions, MimbleWimble, etc?
Jump to: