I am an undergraduate (grade three). I am confused about the cryptanalysis. Because a lot people say that the modern ciphers are complete and they can't be cracked. Maybe the prospects for cryptanalysis are bleak?

In vitalik's post the below is mentioned, This is the pairing. Mathematicians also sometimes call it a bilinear map; the word “bilinear” here basically means that it satisfies the constraints: $e(P, Q + R) = e(P, Q) * e(P, R)$ $e(P + S, Q) = e(P, Q) * e(S, Q)$ Whereas the textbook definition ...