Different jobs need different properties
The Entropy Atlas
Map keys, nonces, salts, shuffles, simulations, beacons, and more by the property each application actually needs.
5 instruments
One claim, three lenses.
Change depth inside any card. “Another example” adapts the lens to the situations you chose during onboarding.
One idea · three lenses
Some numbers are keys
If knowing the number lets someone open the treasure, it must be difficult for them to guess and difficult to observe. A fresh number is not enough if everyone can predict it.
One idea · three lenses
A ticket number can be public and still useful
A coat-check ticket does not need to be mysterious to keep two coats separate. It mainly needs not to repeat while both coats are in the room.
One idea · three lenses
Fairness is about the chances promised
A die roll is fair when each face gets the chance the rules say it gets. A secret seed can still feed a broken rule that favors one face.
One idea · three lenses
Sometimes repeating is the feature
A world seed lets two players visit the same generated island. A test seed lets a developer replay the exact path that found a bug. Here, keeping the recipe matters more than hiding it.
One idea · three lenses
Everyone should see the same honest draw
If several teams need one referee, the number can be public after the whistle. The hard part is stopping any team—or the referee—from choosing the result after seeing who it helps.
Bench notes
Keep these three.
- 01
Secret, unique, fair, reproducible, and publicly verifiable are different requirements.
- 02
A value can be public and still perform its job as a nonce or salt.
- 03
The full process from bits to outcome determines fairness.
Local field-note progress
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