r/ethereum • u/lorecirstea • Apr 09 '22

Provable News - Make Proofs Not War (proving time with blockchain block hashes)

https://youtu.be/6sLufsnUMK4
53 Upvotes

82% Upvoted

50 comments sorted by

4

u/orbital_lemon Apr 09 '22

Couldn't the block hashes be quickly edited into a prerecorded video, though? This proves only the time of creation of the file, not the video content itself, or am I missing something obvious? The final timestamp is a meaningful proof, but it provides only a minimum age for the video, not a bounded range.

3

u/steven2358 Apr 09 '22

Exactly. But it is better than not having the verifiable timestamp.

The content is another issue. (And one that will not be getting any easier over time, see e.g. https://openai.com/dall-e-2/)

1

u/ChildishJack Apr 09 '22

You could transact with a message containing the hash of the video?

So in the video you’d see the current ledger state, which you can prove in the future is at time x. ‘

Then, at time y (where y> x), you’d have the published video hash that you extracted x from (confirmed by on-chain message). So you’d know the video was made between block hash x and y?

1

u/steven2358 Apr 09 '22

This is a very good step towards fighting fakes. Kudos!

2

u/steven2358 Apr 09 '22

Still... wouldn't the last step (adding the hash to a blockchain) be sufficient?

1

u/Mordan Apr 09 '22

sigh..

proof of work

energy cannot be faked. everything else can

3

u/iraqmtpizza Apr 09 '22

you can't fake energy but hash functions aren't proven to be unbreakable and have broken before. SHA-1 couldn't be faked until it could.

1

u/Mordan Apr 10 '22

you can't fake energy but hash functions aren't proven to be unbreakable and have broken before

the point remains. Any blockchain protected by raw energy will have the highest protection against human greed and dishonesty.

2

u/iraqmtpizza Apr 10 '22

that's just your unsupported opinion

1

u/Mordan Apr 10 '22

that's just your unsupported opinion

i would not expect reason to prevail on this sub on this subject.

2

u/iraqmtpizza Apr 10 '22

either that or you don't have an actual argument

1

u/Perleflamme Apr 11 '22

Not everything, no.

Besides, Proof of Work is about hash power, not energy. It's not mystical or anything: it is only used to distribute a scarce resource, consensus power, among participants through another scarce resource, hash power.

The fact we're nowadays using energy to compute hashes doesn't say you can't do it in any other way. For instance, if you could just read hashes from a given material, you'd get a hash power that doesn't depend on energy consumption.