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.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.
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.
Each address is accessible by 294? When I export a private key from an address it only gives one private key to me....
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.