How this works / Signed record

Problem revision

Which massive stars explode and which collapse quietly to black holes?

This record was signed by PubPhys and added to the public log. Download the proof and check it with the open verifier: it recomputes every fingerprint, checks the PubPhys signature against the published key, finds the entry in the log and checks the Bitcoin date, without relying on this site.

Record hash
b9553e5ea789e5133e57b686acc10c026af5e9c7b93606b14fb4f4a0324dfb17
Content hash
bad316be95d86f35e66c9ea785067c8e55f4051576781f2130745f672c37070e
Signed by
c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da
Log entry
500
Checkpoint
Size 2,123, being published
Bitcoin date
Block 969,698
Created (claimed)
2026-10-03T07:17:54Z — the Bitcoin date is the one that counts