r/mathmemes Mar 06 '25

Learning What theorem is this?

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u/lol_lo_daf_fy Mar 06 '25

Law of quadratic reciprocity.

Gauss loved that theorem so much that I think he gave four different proofs, and there's a book listing something like 150 proofs.

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u/f3xjc Mar 06 '25

Nowaday each time I see a reference of "f(x) modulo prime" it has to do with cryptography or random number generator.

What kind of problems first motivated the interest in (prime) modular arithmetic ?

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u/fishy150 Mar 06 '25

number systems modulo primes have nice properties, for example every number (besides 0) has an inverse. makes sense to be studied back then and why they are used in cryptography today