https://www.superphysics.org/research/hilbert/fundamentals/ Recent content in Fundamentals of a general theory of linear integral equations on Superphysics Hugo en Sat, 01 Aug 2026 00:00:00 +0000 https://www.superphysics.org/research/hilbert/fundamentals/chapter-01/ Sat, 01 Aug 2026 00:00:00 +0000 https://www.superphysics.org/research/hilbert/fundamentals/chapter-01/ <p>Let (K(s,t)), (f(s)), (\varphi(s)) be the functions given the meaning introduced at the beginning; however, for the sake of simplicity, let us take the interval of the variables (s,t) as the interval (0) to (1); furthermore, let (K(s,t)) be a symmetric function in (s,t). We further understand by (n) a positive integer and use for the following proofs the abbreviations:</p>