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Willow quantum chip demonstrates verifiable quantum advantage on hardware

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Re: Willow quantum chip demonstrates verifiable quantum advantage on hardware

#101

Post by cyberpunk »

bawolff wrote: post #86
cyberpunk wrote: post #59

Earlier quoted context omitted.

I don’t really understand the threat to banking. Let’s say you crack the encryption key used in my bank between a java payment processing system and a database server. You can’t just inject transactions or something. Is the threat that internal network traffic could be read? Transactions all go to clearing houses anyway. Is it to protect browser->webapp style banking? those all use ec by now anyway, and even if they…

> those all use ec by now anyway As far as i am aware, eliptic curve is also vulnerable to quantum attacks. The threat is generally both passive eavesdropping to decrypt later and also active MITM attacks. Both of course require the attacker to be in a position to eavesdrop. > Let’s say you crack the encryption key used in my bank between a java payment processing system and a database server. Well if you are sitting…

> Well if you are sitting in the right place on the network then you can.

Not really. This would be if not instantly then when a batch goes for clearing or reconciliation, be caught -- and an investigation would be immediately started.

There are safeguards against this kind of thing that can't be really defeated by breaking some crypto. We have to protect against malicious employees etc also.

One can not simply insert bank transactions like this. They are really extremely complicated flows here.

Re: Willow quantum chip demonstrates verifiable quantum advantage on hardware

#102

Post by [deleted] »

nashashmi wrote: post #10

Before the mega monopolies took over, corps used to partner with universities to conduct this kind of research. Now we have bloated salaries, rich corporations, and expensive research while having under experienced graduates. These costs will get forwarded to the consumer. The future won’t have a lot of things that we have come to expect.

[deleted]

Re: Willow quantum chip demonstrates verifiable quantum advantage on hardware

#103

Post by strbean »

jwpapi wrote: post #84
iwontberude wrote: post #78

Earlier quoted context omitted.

As you alluded to, network can have two parallel chains where wallets can be upgraded by users asynchronously before PQC is “needed” (a long way away still) which will leave some wallets vulnerable and others safe. It’s not that herculean as most wallets (not most BTC) are in exchanges. The whales will be sufficiently motivated to switch and everyone else it will happen in the background. A nice benefit is it solves…

Not even needed you can just copy network state of a specific moment in time and encrypt with a new algorithm that will be used from then on

The problem is that the owner needs to claim their wallet and migrate it to the new encryption. Just freezing the state at a specific moment doesn't help; to claim the wallet in the new system I just need the private key for the old wallet (as that's the sole way to prove ownership). In our hypothetical post-quantum scenario, anyone with a quantum computer can get the private key and migrate the wallet, becoming the de-facto new owner.

I think this is all overhyped though. It seems likely we will have plenty of warning to migrate prior to achieving big enough quantum computers to steal wallets. Per wikipedia:

> The latest quantum resource estimates for breaking a curve with a 256-bit modulus (128-bit security level) are 2330 qubits and 126 billion Toffoli gates.

IIRC this is speculated to be the reason ECDSA was selected for Bitcoin in the first place.

Re: Willow quantum chip demonstrates verifiable quantum advantage on hardware

#104

Post by bossyTeacher »

Afaik we are a decade or two away from quantum supremacy. All the AI monks, forget that if AI is the future, quantum supremacy is the present. And whoever controls the present, decides the future.

Rememeber, it is not about quantum general computing, it's about implementing the quantum computation of Shor's algorithm

Re: Willow quantum chip demonstrates verifiable quantum advantage on hardware

#105

Post by cyberpunk »

bawolff wrote: post #93
cyberpunk wrote: post #85

Earlier quoted context omitted.

Okay, but breaking that TLS (device->bank) would allow you to intercept the session keys and then decrypt the conversation. Alright, so now you can read I logged in and booked a transaction to my landlord or whatever. What else can you do? OTP/2FA code prevents you from re-using my credentials. Has it been demonstrated at all that someone who intercepts a session key is able to somehow inject into a conversation? It…

> Has it been demonstrated at all that someone who intercepts a session key is able to somehow inject into a conversation? It seems highly unlikely to me with TCP over the internet. if you can read the TLS session in general, you can capture the TLS session ticket and then use that to make a subsequent connection. This is easier as you dont have to be injecting packets live or make inconvinent packets disappear.

It seems like detecting a re-use like this should be reasonably easy, it would not look like normal traffic and we could flag this to our surveillance systems for additional checks on these transactions. In a post quantum world, this seems like something that would be everywhere anyway (and presumably, we would be using some other algo by then too).

Somehow, I'm not all that scared. Perhaps I'm naive.. :}

Re: Willow quantum chip demonstrates verifiable quantum advantage on hardware

#106

Post by refulgentis »

FabHK wrote: post #100

So, "verifiable" here means "we ran it twice and got the same result"? > Quantum verifiability means the result can be repeated on our quantum computer — or any other of the same caliber — to get the same answer, confirming the result.

Sounds like N, not 2

Re: Willow quantum chip demonstrates verifiable quantum advantage on hardware

#107

Post by chuckadams »

markx2 wrote: post #7

> In physics, a quantum (pl.: quanta) is the minimum amount of any physical entity (physical property) involved in an interaction. Not a big leap then.

I see what you did there. Shame a lot of other people didn't.

Re: Willow quantum chip demonstrates verifiable quantum advantage on hardware

#108

Post by cyberpunk »

chuckadams wrote: post #99
cyberpunk wrote: post #59

Earlier quoted context omitted.

I don’t really understand the threat to banking. Let’s say you crack the encryption key used in my bank between a java payment processing system and a database server. You can’t just inject transactions or something. Is the threat that internal network traffic could be read? Transactions all go to clearing houses anyway. Is it to protect browser->webapp style banking? those all use ec by now anyway, and even if they…

Flooding the system with forged messages that overwhelm the clearinghouse having to verify them sounds like a good way to bring down a banking system.

Sure, if a bank gets compromised you could in theory DOS a clearing house, but I'd be completely amazed if it succeeded. Those kind of anomalous spikes would be detected quickly. Not even imagining that each bank probably has dedicated instances inside each clearing house.

These are fairly robust systems. You'd likely have a much better impact dossing the banks.

Re: Willow quantum chip demonstrates verifiable quantum advantage on hardware

#109

Post by udev4096 »

bilsbie wrote: post #51
ransom1538 wrote: post #25

Earlier quoted context omitted.

SO... BTC goes to zero?

I don’t see why bitcoin wouldn’t update its software in such a case. The majority of minors just need to agree. But why wouldn’t they if the alternative is going to zero?

The problem is all the lost BTC wallets, which is speculated to be a lot and also one of the biggest reason for the current BTC price, who obviously cannot upgrade to PQ. There is currently a radical proposal of essentially making all those lost wallets worthless, unless they migrate [1]

[1] - https://github.com/jlopp/bips/blob/quantum_migration/bip-pos...

Re: Willow quantum chip demonstrates verifiable quantum advantage on hardware

#110

Post by chuckadams »

cyberpunk wrote: post #108
chuckadams wrote: post #99

Earlier quoted context omitted.

Flooding the system with forged messages that overwhelm the clearinghouse having to verify them sounds like a good way to bring down a banking system.

Sure, if a bank gets compromised you could in theory DOS a clearing house, but I'd be completely amazed if it succeeded. Those kind of anomalous spikes would be detected quickly. Not even imagining that each bank probably has dedicated instances inside each clearing house. These are fairly robust systems. You'd likely have a much better impact dossing the banks.

Yah, I suspect the banks pay a handsome sum to smarter people than you and me, and they've gamed this out already.
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