is Quantum Computing a threat to Bitcoin?

[floridaman86]

I don't know enough about quantum computing to know if it is an actual threat to the future of bitcoin. I have heard arguments on both sides, but mostly from people that I feel do not have a very good understanding of bitcoin.

Any thoughts?

[DubemIfedigbo001]

While quantum computing might not be a threat to bitcoin directly, yet it is a threat to the security of funds when you reuse addresses. This is because when you use an address, your public key is exposes and with quantum computing, it can be possible to compute your private keys from your exposed public key.

It is better you don't reuse addresses, You can mitigate this risk by moving your funds to a new unused address each time you use an address so that your coins are safe in the new unused address.

[thecodebear]

While quantum computing might not be a threat to bitcoin directly, yet it is a threat to the security of funds when you reuse addresses. This is because when you use an address, your public key is exposes and with quantum computing, it can be possible to compute your private keys from your exposed public key.

It is better you don't reuse addresses, You can mitigate this risk by moving your funds to a new unused address each time you use an address so that your coins are safe in the new unused address.

Yeah this is also what I understand the threat to be.

QC can break encryption from public key to get the private key. So QC is only a threat for when you reuse an address as the public key is only exposed when you send a transaction. Though it also means the ~2 million bitcoin sitting in addresses from back in the real early days of bitcoin (when bitcoin was sent directly to public keys rather than public addresses) are just sitting around ripe for the picking for when QC gets mature enough to break the encryption. So that is the main threat, the ~2 million btc that WILL eventually get stolen by QC at some point in the future. Of course some of that btc are still controlled by people and they can move it to new addresses, but the majority of those coins are likely lost coins, and so would eventually be stolen in a QC world.

I did see recently there is some proposal about eventually essentially blacklisting those QC-susceptible addresses basically, or I think maybe the proposal was actually to have everyone move to an even newer address type and not allowing any current address types in the future, i don't remember what the exact proposal was, but that is what I proposed on here maybe a couple years ago - that unless some action is taken there will be ~2 million bitcoin that get stolen at some point in the future from QC and so at the very least that original pay to public key transactions should be blacklisted, thus preventing the threat of QC stealing those ~2 million lost bitcoin from 2009/2010 time period.

[betswift]

By the time it is available to everybody eager to try to ruin your day, Bitcoin will probably become quantum-proof, so don't worry too much about it.

[DubemIfedigbo001]

By the time it is available to everybody eager to try to ruin your day, Bitcoin will probably become quantum-proof, so don't worry too much about it.

It's better to play safe than exposing yourself to threats and hoping that an imaginary fix would protect you. The quantum computing technology is advancing and I see bigger threats for reused addresses.

Do yourself a favor, don't reuse addresses and if eventually Bitcoin addresses gets quantum proof, it's a double advantage.

[betswift]

By the time it is available to everybody eager to try to ruin your day, Bitcoin will probably become quantum-proof, so don't worry too much about it.

It's better to play safe than exposing yourself to threats and hoping that an imaginary fix would protect you. The quantum computing technology is advancing and I see bigger threats for reused addresses.

Do yourself a favor, don't reuse addresses and if eventually Bitcoin addresses gets quantum proof, it's a double advantage.

You are right, probably, I am just optimistic about it, because by the time such tech will become available for most of the people, firstly, BTC wouldn't be the first target to be broken (because it isn't the biggest target out there), and secondly, there probably will be a solution to it.

[btc_angela]

I don't know enough about quantum computing to know if it is an actual threat to the future of bitcoin. I have heard arguments on both sides, but mostly from people that I feel do not have a very good understanding of bitcoin.

Any thoughts?

To give you a hint, we have a lot of threads about it,

• Quantum computing and the future of bitcoin.
• Emerging Solutions for Quantum Computing Threats
• Quantum Computers Can Not Defeat Bitcoin, not even The Bitcoin Network
• Is Willow (Google new quantum computer chip) going to kill Bitcoin?
• "Quantum computing"
• Bitcoin will be vulnerable to Quantum Computers in about 2 years

So just probably go to that thread and read everything about it. And the reason behind not using a Bitcoin addresses is that your public key will not be exposed.

Or if the threat is real then Bitcoin developers might replaced the existing SHA-256 with a more quantum resistant has function.

[FortuneFollower]

^ Bitcoin would not be the first on the list to be "broken", that's for sure, and, indeed - there are many ways to go around that concern and just see, that, we are probably are going to be prepared when the threat eventually comes.

[SUPERSAIAN]

I don't know enough about quantum computing to know if it is an actual threat to the future of bitcoin. I have heard arguments on both sides, but mostly from people that I feel do not have a very good understanding of bitcoin.

Any thoughts?

To give you a hint, we have a lot of threads about it,

• Quantum computing and the future of bitcoin.
• Emerging Solutions for Quantum Computing Threats
• Quantum Computers Can Not Defeat Bitcoin, not even The Bitcoin Network
• Is Willow (Google new quantum computer chip) going to kill Bitcoin?
• "Quantum computing"
• Bitcoin will be vulnerable to Quantum Computers in about 2 years

So just probably go to that thread and read everything about it. And the reason behind not using a Bitcoin addresses is that your public key will not be exposed.

Or if the threat is real then Bitcoin developers might replaced the existing SHA-256 with a more quantum resistant has function.

This is also my opinion, if quantum computers become a threat, bitcoin developers will not stand still, they will respond with a more resilient system. I hear that current quantum computers are far from breaking ECDSA or SHA-256 because of their high error rates and limited number of qubits, and moreover, they say that it will take 10-20 years to develop the quantum computers needed to break the Bitcoin network.

[nemesis_incarnate]

I don't know enough about quantum computing to know if it is an actual threat to the future of bitcoin. I have heard arguments on both sides, but mostly from people that I feel do not have a very good understanding of bitcoin.

Any thoughts?

To give you a hint, we have a lot of threads about it,

• Quantum computing and the future of bitcoin.
• Emerging Solutions for Quantum Computing Threats
• Quantum Computers Can Not Defeat Bitcoin, not even The Bitcoin Network
• Is Willow (Google new quantum computer chip) going to kill Bitcoin?
• "Quantum computing"
• Bitcoin will be vulnerable to Quantum Computers in about 2 years

So just probably go to that thread and read everything about it. And the reason behind not using a Bitcoin addresses is that your public key will not be exposed.

Or if the threat is real then Bitcoin developers might replaced the existing SHA-256 with a more quantum resistant has function.

This is also my opinion, if quantum computers become a threat, bitcoin developers will not stand still, they will respond with a more resilient system. I hear that current quantum computers are far from breaking ECDSA or SHA-256 because of their high error rates and limited number of qubits, and moreover, they say that it will take 10-20 years to develop the quantum computers needed to break the Bitcoin network.

And that is considering that these quantum machines wouldn't be as widespread as we need even in these 10 years..

[floridaman86]

While quantum computing might not be a threat to bitcoin directly, yet it is a threat to the security of funds when you reuse addresses. This is because when you use an address, your public key is exposes and with quantum computing, it can be possible to compute your private keys from your exposed public key.

It is better you don't reuse addresses, You can mitigate this risk by moving your funds to a new unused address each time you use an address so that your coins are safe in the new unused address.

I'm a little bit confused on this because, my wallet generates a new bitcoin address anytime I use it. So why would it be necessary to move my coins every time I use it? Isn't that the point of the wallet generating a new address every time it is used?

[DubemIfedigbo001]

While quantum computing might not be a threat to bitcoin directly, yet it is a threat to the security of funds when you reuse addresses. This is because when you use an address, your public key is exposes and with quantum computing, it can be possible to compute your private keys from your exposed public key.

It is better you don't reuse addresses, You can mitigate this risk by moving your funds to a new unused address each time you use an address so that your coins are safe in the new unused address.

I'm a little bit confused on this because, my wallet generates a new bitcoin address anytime I use it. So why would it be necessary to move my coins every time I use it? Isn't that the point of the wallet generating a new address every time it is used?

I guess you use a HD wallet. When your wallet generates a new address for you, it's for receiving a new transaction and to increase privacy. It does not automatically move the funds to a new address unless you choose to do it manually.

The new address is empty and your UTXOs remains in the old address, the main point is not to reuse the old address, next time you're accepting a pay, make use of the new address.

When there are multiple UTXOs in different addresses, target a time the fees are low and consolidate some of the UTXOs in yet a new address to reduce fees when you want to send more funds across at a time.

[finaleshot2016]

I don't know enough about quantum computing to know if it is an actual threat to the future of bitcoin. I have heard arguments on both sides, but mostly from people that I feel do not have a very good understanding of bitcoin.

Any thoughts?

Well, this topic has been here for how many years already and this is a great topic that could really affect bitcoin in the future since we're not far from having advanced technology like quantum computing. I mean we're far but as you can see in our technology development, it's quite fast and instant. Really concerning tho since it might decode the cryptographic of BTC which can be a major flaw in the future. But I'm for sure that the people behind crypto are trying to research and study more about it, ofc they won't let it happen.

[Outhue]

Calm down people, who will have access to a quantum computer? Even the fastest laptops today costs from $5000 so you expect quantum computer to cost how much..? Billions of people won't be able to afford one.

Also, once this quantum computer became possible every possible threat that can impart what's already working in the world today will have a fix including blockchain, a patch will come up before Quantum Computer goes public.

A super computer is automatically a threat today, if someone have this it will be those from secret service, not for public type of shit, you are not the only one sensing how dangerous this can be, even your leaders and the government are feared about give such power to the public.

[Bastketsrus]

I don't know enough about quantum computing to know if it is an actual threat to the future of bitcoin. I have heard arguments on both sides, but mostly from people that I feel do not have a very good understanding of bitcoin.

Any thoughts?

It's a valid concern, but still a long way off. Bitcoin devs are aware and already exploring quantum-resistant options. Nothing to worry about right now.

[yhiaali3]

Theoretically, there are concerns that quantum computing could be able to extract the private key from the exposed public key. This is possible with legacy wallets, where the public key is exposed, but not with modern wallets like SegWit or Taproot.

Twice or three months ago, Tether's CEO made statements that quantum computing would be able to hack "lost" Bitcoin wallets and restore them to circulation, including Satoshi's wallet. However, he believes this is still a long way off:
https://cointelegraph.com/news/quantum-computing-bitcoin-lost-wallet-threat-tether-ceo

In my opinion, these concerns are still far fetched, and so called anti-quantum cryptography, or post-quantum cryptography (PQC), is being developed, which will make things much more difficult.

[coolcoinz]

In short:

1. It's not a threat yet, but might be in 10 years when they find out how to translate between languages, enabling quantum machines to read binary data and then translating it back into binary for normal computers to compile.

2. When it finally becomes a threat to bitcoin, it will also be a threat to any other secure system. How do you think bank accounts are secured? Do you think your president's email address is fine if they can crack bitcoin? What about stock exchanges, social security payments and so on?

[cryptomaniac_xxx]

In short:

2. When it finally becomes a threat to bitcoin, it will also be a threat to any other secure system. How do you think bank accounts are secured? Do you think your president's email address is fine if they can crack bitcoin? What about stock exchanges, social security payments and so on?

I'm thinking that it could be as "bad" as supposedly Y2K before when everyone is one panic mode and then they say that we will have a problem. Nevertheless, it was solved very quickly without any hitch.

So probably that's what going to happen here, when that time arrives, everyone has adjusted already and so there will not be a huge impact in our lives. So we should relaxed by now, Bitcoin developers could have their solutions already.

[NotFuzzyWarm]

Just how many more of these "QC threat to BTC" threads will folks create? There are literally over a dozen or more... Apparently folks are too lazy to bother checking if 'their new question' has already been discussed to death... ALL have the same answers - not an immediate problem because there are NO viable QC's yet and yes there are already solutions that exist to address it when it finally is needed.

The quantum computing technology is advancing ...

Yes but it is still deeply in the 'make a memory cell array' (qbit) stage. We are a LONG way from making a QC that can solve even the simplest problems.

[aoluain]

Its been a while since we had a QC threat thread, it was about time we had one !

btc_angela has posted a selection of "previous" threads.

The way I see it is that when QC become a threat our Bitcoin developers will already
have QC defences in place so the threat will be balanced just the same as 
computing is today, it can be used for good and bad.