cliffbjanger on Nostr: So quantum FUD is doing the rounds again. I'm not concerned. Here is my take: In ...
So quantum FUD is doing the rounds again. I'm not concerned. Here is my take:
In Bitcoin, you have a "master private key" that is used to derive a tree of private keys with corresponding public keys (the addresses you use to receive funds). It is not possible to derive the "master private key" from private keys further down the tree. However, quantum computers could — theoretically — calculate a private key using specific algorithms if they have access to a public key (pubkey).
When you receive funds in a Bitcoin transaction, only your address is visible on the blockchain. This address is a hash of a pubkey. In other words, no pubkey is visible on the blockchain when you receive funds. Even for quantum computers, it is extremely unlikely to guess a pubkey from a hashed address. It is when you send funds from an address that the pubkey becomes exposed, making the corresponding private key vulnerable. However, the "master private key" remains secure.
The solution to protect yourself is simple: don’t reuse addresses. Modern wallets often generate new addresses automatically, both for incoming transactions and for "change addresses" — the addresses where the remaining funds from a transaction are sent back to you.
By avoiding address reuse, you ensure that the public keys exposed on the blockchain can only lead quantum computers to private keys that no longer control any funds.
In Bitcoin, you have a "master private key" that is used to derive a tree of private keys with corresponding public keys (the addresses you use to receive funds). It is not possible to derive the "master private key" from private keys further down the tree. However, quantum computers could — theoretically — calculate a private key using specific algorithms if they have access to a public key (pubkey).
When you receive funds in a Bitcoin transaction, only your address is visible on the blockchain. This address is a hash of a pubkey. In other words, no pubkey is visible on the blockchain when you receive funds. Even for quantum computers, it is extremely unlikely to guess a pubkey from a hashed address. It is when you send funds from an address that the pubkey becomes exposed, making the corresponding private key vulnerable. However, the "master private key" remains secure.
The solution to protect yourself is simple: don’t reuse addresses. Modern wallets often generate new addresses automatically, both for incoming transactions and for "change addresses" — the addresses where the remaining funds from a transaction are sent back to you.
By avoiding address reuse, you ensure that the public keys exposed on the blockchain can only lead quantum computers to private keys that no longer control any funds.