@chjara@snowdin.town HOWEVER i think this is v cool to explain what a homomorphism is???
@chjara@snowdin.town @koakuma@uwu.social yeah so the basic idea would go like this:
most mathematical operations tend to "forget" what you're doing inside of them, so for example(a+b)^2=a^2+b^2+2ab; \sin(a+b)= \sin(a)\cos(b)+\sin(b)\cos(a)
certainly, there is "extra information" that you CAN use, but then you need to know what a
and b
are; in other words, take my hand you either know what a+b
is, or know what a
and b
are
however, there are other operations that "remember" the fact you had an operation, say,(a+b)c=ac+bc; 2^{a+b}=2^a2^b
note how the operation is not necessarily the same! but you still have the sum encoded in some way, so you don't need to know what a+b
is in order to compute 2^{a+b}
@chjara@snowdin.town @koakuma@uwu.social so how it factors in hom-encryption is that you can just use these black-box pieces of information and work with them without any extra resources, because there is an equivalent black-box opeartion that takes care of it!
@placholdr That usually uses very different principles, but it is also very much in the cryptographic tradition of "how to know nothing in a useful way".