Compact operators K: B(X)→B(X) (image of unit-ball precompact). Fredholm-alternative for I-K (cross-listed L0 integral-eq). Spectrum of compact-self-adjoint = discrete eigenvalues → 0.
Compact operators K: B(X)→B(X) (image of unit-ball precompact). Fredholm-alternative for I-K (cross-listed L0 integral-eq). Spectrum of compact-self-adjoint = discrete eigenvalues → 0.