Quote from: Saint-loup on October 23, 2017, 08:13:30 PM

Quote from: odolvlobo on October 23, 2017, 08:07:20 PM

Quote from: Saint-loup on October 23, 2017, 07:32:26 PM

Quote from: llama_rider on October 23, 2017, 07:13:28 PM

One possibility is that advances in cryptanalysis or quantum computing eventually break SHA256 or ECDSA secp256k1. With any luck, this would be gradual process (as with MD5 and SHA1), so that there is time for an orderly hard fork to a different digital signature algorithm or cryptographic hash algorithm. Then the UTXOs with lost private keys can either be formally destroyed as part of the hard fork or claimed by whoever first cracks them.

And as Saint-loup notes, if Moore's Law continues long enough, even brute force attacks might eventually compromise the cryptographic primitives currently used by Bitcoin.

you seem to be very educated.

Do you know what is the probability to import an account with some money in it when a user enter a random private key?

AFAIK, there are "only" 52^62 potential private keys. ie 52 characters in lowercase, uppercase or digit.

Your numbers are off. A bitcoin address is an encoding using base-58. The actual number of possible addresses is 2¹⁶⁰, and each address is shared by nearly 2⁹⁴ private keys.

thank you but I don't understand what "each address is shared by nearly 2⁹⁴ private keys." means...
Each address is accessible by 2⁹⁴? When I export a private key from an address it only gives one private key to me.... Undecided

Sorry, typo. Should be 2⁹⁶
For every bitcoin address, there are nearly 2⁹⁶ private keys that are associated with it. That is because there are 2¹⁶⁰ addresses, but nearly 2²⁵⁶ private keys.