corpus · reviewed 2026-09-09
hard-
fucking-
problems
339 unsolved and contested problems. For each one: the barrier, and the closest anyone has come.
- 339
- problems
- 22
- domains
- 1,693
- of 1,696 citations verified
scroll ↓ · point at a line · click to open it
01 / 06
Each line is one problem.
It starts the year someone posed the problem. It runs until the problem is closed. 330 of 339 run off the right edge: still open.
1611
The oldest. Optimal sphere packing density in general dimension. Open for 415 years.
Time is on a log scale, counted back from 2026. 30 problems have no known posed year; they start at their first milestone.
02 / 06
Each dot is an approach.
1,554 milestones. Every one states the gap that remained after it.
988
carry a year of 2020 or later.
A closest approach is the best the research team found. It is not a survey guarantee.
03 / 06
Some fronts went quiet.
The same problems, grouped by the year of the last milestone.
19years
Beal Conjecture. Nothing since 2007.
11 open problems have no milestone after 2019.
04 / 06
The bar is evidence, not respectability.
Colour is the evidence tier. Tier 0 is textbook consensus. Tier 4 is fringe: evidence exists, but it is disputed or single-source.
21
problems sit at tier 3 or 4. Each one must carry the positive result and the mainstream objection, both cited.
05 / 06
9 are closed.
3 were solved. 5 were tested and found false in the form they were first stated. 1 never stated anything that can be tested. They stay in the corpus, with the evidence that closed them.
06 / 06
Now look.
339 problems · press / to search
Oldest
Quiet longest
Largest bounties
hard-fucking-problems · generated 2026-09-09 · link rot is real