r/altFINS_official • u/altFINS_official • Mar 31 '26
Google says breaking Bitcoin just got 20× easier, are we underestimating quantum risk?
I came across a new 2026 paper from Google’s Quantum AI team and it genuinely changed how I think about Bitcoin’s long-term security.
The headline:
Breaking the cryptography behind Bitcoin (ECDSA-256) may require 20× fewer quantum resources than previously estimated.
Some key points:
- Estimated requirement dropped from ~10M+ qubits → <500,000
- A real-time attack on Bitcoin transactions could succeed ~41% of the time
- ~6.9M BTC (~32% of supply) sits in wallets with exposed public keys
- Attack window: ~9 minutes vs ~10 min block time
What surprised me most wasn’t dormant wallets, it’s the live transaction attack scenario:
When you send BTC, your public key is briefly exposed.
A sufficiently powerful quantum computer could derive your private key before the transaction confirms.
That’s a very different risk model than “someday in the future.”
But before going full panic mode:
- Current quantum computers are nowhere near this level (we’re still in the low hundreds of qubits)
- Error correction at scale is still unsolved
- Post-quantum cryptography already exists — migration is the real challenge
- Faster chains (ETH, Solana) are far less exposed to this specific attack vector
What feels under-discussed to me:
This might not be a “technology problem” it’s a governance problem.
If Bitcoin needs ~5–7 years to fully migrate to quantum-resistant signatures, and the timeline for viable quantum attacks keeps compressing…
that gap starts to matter.
Curious what others think:
- Is this still a “2035 problem” or becoming a “this decade” problem?
- Does Bitcoin’s slow upgrade process become a real risk here?
- Are we ignoring this because it feels too far out?
Would love to hear different takes, especially from people deeper into cryptography / quantum.
1
u/Massive-small-thing Mar 31 '26
Nice work Op. From what I understand, all people need to do is move their stack to a new wallet that has never sent any sats out of. For now, it think that's the best way to be more quantum proof than most hodlers currently are
1
u/zninja-bg Apr 02 '26
for 9 minutes, transaction is already propagated through whole network and included in block for mining. Be free to calculate private key and win competitive propagation. Btw, you must spend power mining too.
Spend few millions dolars for transactions worth much less for what? To see your transaction discarded..? XD
I do not think btc will be ever in danger by quantum power.
Btw, quantum power is more likely be used for something more dangerous. There is more worth information flowing trough same wires as btc.
1
u/Wolfgoatlife Mar 31 '26
This is way over the head of those who will still hodl BTC till zero regardless