What makes cryptocurrencies secure against quantum threats?

Lately, I've been seeing a lot of talk about how quantum computers might seriously threaten Bitcoin and other cryptos. But then there are these coins that claim to be "quantum safe". I get that there's still a long way to go before quantum computers can actually endanger Bitcoin, but I can't help but wonder about the future and if our BTC stash is in jeopardy. So here’s what I’m curious about: What actually makes a cryptocurrency quantum safe? And is there a chance Bitcoin could be updated to handle quantum threats?

Your bitcoin is safe from quantum computers if you do not reuse your bitcoin address, the addresses that will be affected are those that their public keys have been exposed. If you spend from your address, your public key will be exposed, so do not reuse address. Yes, there are proposals already.

Since they said stuff like this, do they explain why that's the case? I'd be surprised if they're just throwing claims and people believe them, even if they're just retail traders with little to no experience. It feels like "quantum safe" is becoming another term that gets mentioned so many times, like "military grade encryption". I think this convo about quantum resistance algorithm has been going on for years too, so it's not really new afaik.

From what I understand, if you want to be quantum safe then don't used the same Bitcoin address. Or move your existing Bitcoin to a new address. For sure Bitcoin developers have seen it already, and they might be already prepared. Yes, Bitcoin can be upgraded, right now if I'm not mistaken, we're using existing SHA-256. Perhaps in the future they could developed quantum resistant hash function.

Got curious to research about what are those cryptocurrencies which is quantum safe as what you have said and here is the result https://coinmarketcap.com/view/quantum-resistant/ Also for what I know yes Bitcoin can be upgraded to be quantum safe, but this collective decision by node operators, developers and miners to implement this new cryptographic standard. This situation seems hard to happen if no coordination will happen. But let see if Bitcoin network evolves in future in response to that quantum threat.

Completely random projects, well expected because this is nothing more a selling strategy for those team and may not even be real that they are resistant to wuantum attacks. The Bitcoin network is not in any danger because we are far too early for quantum computing to become real that will be able to affect the exposed public keys of Bitcoin addresses and access the coins. And to make it quantum safe we just need to fork it.

Quantum computers pose a threat to complex mathematical problems, especially in crypto, but so far we haven't seen any real, or direct threat from quantum computers. I don't think quantum computers exist yet, or perhaps they are still in their infancy. If quantum computers do exist, then I think it is possible that all types of cryptocurrencies will be impacted by the speed of their calculations. I don't know exactly how crypto will handle it, but it is clear the digital world is in trouble, including banking security.

Let me try attempt on your question. 1. Bitcoin network protocols are part of the solid evidence that backs it up as being unable to be altered, which is the reason for its immutability, more about blockchain technology could also be learnt well. 2. I don't know if by now it's seeing quantum as a threat as some would have claimed, the nodes are not going to be easily attacked except there's a break in the protocols of the blockchain technology on the bitcoin network.

How many Bitcoin do you have though, that you are this worried about Bitcoin? Leave the worries to those who have 100 BTC and more because if these people are not moved about quantum computer so should you, we have discussed this many times before you can use the forum search to find many quantum computer discussions. Bitcoin is not abandoned, they are devs working all the time, if quantum computer is ever going to be a problen a single update is enough to fix the problem, you are not a developer yourself so I suggest you should focus on getting more Bitcoin, have you seen any quantum computer lately? That's another reason why you should calm down, even if one will exists it will cost alot of money, the computer builders of the world haven't made such machine yet.

We've heard rumors of progresses from Google, IBM and others but reading their processes you'll only get to observe that they only made a chip or two that were able to solve problems faster than others, but none is able to give and tangible breakthrough that may be concerning. I believe quantum technology it's still in it's baby research stages and not what we should trouble ourselves with at the moment, OP should be more concerned with acquiring more stashed of Bitcoin and practicing security and self-custody and not what he doesn't have any control over. Making Bitcoin quantum resistance is the job of the devs, when it's obvious that it's the time to get one step ahead of quantum technology with a patch on the code, they'll do it.

I'll start by saying that I also believe the real threat posed by quantum computers is still far from real. The practice already suggested of moving funds to a second address allows the public key of the second address to be omitted from the blockchain (until it's not used to spend money). This reduces the attack surface of a quantum algorithm, but the public information of the second address is also "attackable." The address is the hash of the public key, and while even more complicated to decrypt, it will be sufficient for an even more powerful quantum algorithm to decode the key.

I think quantum computing is still hypothetical as well, since there is no real product even though it was coined decades ago. Anyway, assuming the computer exists and actually works, I believe P2PK addresses would be the first to be broken since the addresses are not protected behind hashes. The next would be reused addresses that reveal their public key. So as long as you do not reveal your public key, it should be secure enough.

It means that cryptocurrency private key can't be cracked with new quantum computers. Bitcoin can be upgraded to be quantum safe, but this needs to be done with another fork and with significant code changes. Things are getting serious with quantum computers and I think we have maybe 5 years to figure it out what to do with bitcoin code.

This would be one place where you would expect the government to put in place some regulations to never allow quantum computer pose any significant threat to Bitcoin. Government have taken the initiative to invest with Bitcoin, even though they use some strategy that doesn’t involve them buying Bitcoin directly with fiat, they still acquire it for their national reserves and that’s an asset what protecting. Quantum computers isn’t any portable and requires a lot of resources to operate and as such, it could be very limited in our world and so would the threat to Bitcoin.

Well let assume it can, what you meant is exposure of public key for the whole surprise to happen.. While using same address is bad for privacy, it doesn’t expose anything so far you don’t move the SATS anywhere, all exposed is the double hash[RIPEMD160(SHA256(pub))] of the public  key pushed into the ScriptPubKey ( you can verify  through a transaction on mempool) which is safe. Once you spend, the real public key gets exposed (you can check the witness of a segwit transaction you will find it as second item on the stack). Only applicable to segwit though.. Thus, moving existing Bitcoin to a new address doesn’t pose any risk either, only the old address public key is exposed.. now , using that same old address could be risky if Mr Q can actually perfect it job.

I have read this. They need to migrate to post-quantum algorithms. This situation requires consensus agreement from the developers. And I think it should be done immediately. They must adopt post-quantum cryptography (PQC), which are algorithms designed to withstand overlapping attacks. For example, methods like hash-based signatures that are resistant to parking, such as XMSS. This update is carried out through protocol updates or hard forks. Currently, NIST is developing standards for quantum-resistant algorithms like XMSS. Another example is that Algorand currently uses a Verified Randomness Function (VRF) that is vulnerable and is looking for safer post-quantum VRF methods such as ZKBoo and ZKB++. CMIIW Source: https://www.gate.com/id/learn/articles/post-quantum-cryptography-in-blockchain-security/1061

Absolutely nothing. That's the nature of cryptography. For the past 1000 years all cryptography algorithms that humanity has come up with has had an expiration date (people were encrypting their messages long before computers were invented). And they always get replaced by a better and stronger algorithm. The reason why bitcoin is safe is because all the cryptography algorithms it uses are secure and are going to remain secure for a long time. Of course. If ECDSA or SHA256 for example be at a risk of being broken, we can find replacements in the time we will have before they become obsolete and fork Bitcoin to use those algorithms instead.

What are you saying? So you mean signature campaign earners who spend from their rewards would have to inform the campaign managers to update new address every week to avoid exposure to quantum computers? The public key you talking about is the same as wallet address, can't get it.

If quantum computing become a threat, definitely there will be an upgrade to bitcoin network that will be quantum resistant. But if there is no such upgrade before the time, campaign managers will better request for new addresses every week. If they can work with silent payment, it will be a good alternative. You can read more about the differences between public keys and addresses, they are different.

You guys are making a big deal out of something that's not in existence yet, the vitalik tweet on x was fake I read, even if it is real know that Bitcoin and Ethereum are both quantum upgrade ready, the fix won't even take a day to inject into these two projects. Quantum computers are also a threat to everything, not just Bitcoin only, that is why safety procedure will have to be in place first before they permit any quantum computers to function. Now everyone is making this look like weapon of mass destruction, if truly it is, it is not going to exist because it will be a big threat that must not exist.I doubt it will work and if it does work it won't affect Bitcoin.