Some algorithms based upon a projection process onto the Krylov subspace $K_m = \operatorname{Span}(r_0, Ar_0, \ldots, A^{m - 1}r_0)$ are developed, generalizing the ...

Two weeks ago, a modest-looking paper was uploaded to the arXiv preprint server with the unassuming title “On the invariant subspace problem in Hilbert spaces”. The paper is just 13 pages long and its ...

Gravitational lensing often evokes images of a cosmic funhouse mirror: duplicated galaxies, dramatic arcs and distorted shapes. But the web-like, large-scale structure throughout the universe also ...