Minkowski space by Ciro Santilli 37 Updated 2025-07-16
with a weird dot product-like operation called the Minkowski inner product.
Because the Minkowski inner product product is not positive definite, the norm induced by an inner product is a norm, and the space is not a metric space strictly speaking.
The name given to this type of space is a pseudometric space.
Just like the adenine nucleotide translocator moves ATP/ADP in and out, this one moves loose phosphate in.
Both of those together recycle the cellular respiration carriers from/to the mitochondria.
Cycler Turing machine by Ciro Santilli 37 Updated 2025-07-16
These are very simple, they just check for exact state repetitions, which obviously imply that they will run forever.
Unfortunately, cyclers may need to run through an initial setup phase before reaching the initial cycle point, which is not very elegant.
Also, we have no way of knowing the initial setup length of the actual cycle length, so we just need an arbitrary cutoff value.
And unfortunately, this can lead to misses, e.g. Skelet machine #1, a 5 state machine, has a (translated) cycle that starts at around 50-200M steps, and takes 8 trillion steps to repeat.
The Sims by Ciro Santilli 37 Updated 2025-07-16
A young Ciro Santilli really liked this game, the way it makes you feel.
This is the discrete logarithm problem where the group is a cyclic group.
In this case, the problem becomes equivalent to reversing modular exponentiation.
This computational problem forms the basis for Diffie-Hellman key exchange, because modular exponentiation can be efficiently computed, but no known way exists to efficiently compute the reverse function.
Big O notation family by Ciro Santilli 37 Updated 2025-07-16
This is a family of notations related to the big O notation. A good mnemonic summary of all notations would be:

Pinned article: Introduction to the OurBigBook Project

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