nist-inject

oin block hashes are even better, as the proof-of-work ensures that even trying to force a single bit of the block hash is extremely expensive. I also run a project to inject other random beacons into the Bitcoin blockchain, such as the NIST Random Beacon: https://github.com/opentimestamps/nist-inject But in the age of deep fakes, what does any of this actually prove? See, while a timestamp proof mathematically depends on your message, with a random beacon it's the opposite: your message needs to depend on the random beacon. For human meaningful messages that's not easy to achieve. A photo can be photoshopped, a video deepfaked, etc. The best you can do in general is try to make the random beacon time, and the timestamp, be as close together as possible to make it as difficult as possible to do a photoshop, deepfake, etc. But deepfakes are good enough these days that IMO that's dubious security. Probably the best approach here is to actually think about what exactly you are trying to achieve - are you kidnapping someone? proving you've recovered from the plague? launching a cryptocurrency? There isn't a one-size-fits-all solution to this problem.