{"id":"palomar/PALOMAR-2026-08-26-000002","url":"https://github.com/lukasliehr/GrothendieckBessel/tree/f1ad1c7680bce2b1ab4218a02bddd694fb57062a","json":"https://data.palomar-registry.org/entries/PALOMAR-2026-08-26-000002-v1.json","repo":"https://github.com/lukasliehr/GrothendieckBessel","tags":["math.FA","math.CA","msc:46B15","msc:46B25","msc:42C15","msc:68V20","functional-analysis","harmonic-analysis","lean","bessel-sequences"],"score":0,"title":"lukasliehr/GrothendieckBessel","trust":"high","domain":"math.FA","source":"palomar","authors":["Lukas Liehr","Mitchell A. Taylor","Peiyang Yu"],"reviews":0,"subject":"math.FA","summary":"A Lean 4 formalization of the existence assertion in Theorem 1.1 of arXiv:2608.12280v1 with the sharp constant K = 1: for every countable Bessel sequence with bound 1 in a complex Hilbert space, there exist measurable functions on the unit interval, pointwise bounded by 1, whose correlations reproduce the sequence's Gram matrix. This solves an open problem posed by Olevskii.","category":"research","comments":0,"disputed":false,"division":"math","mentions":0,"verified":true,"discussed":0,"published":"2026-08-26","reactions":{},"formalized":true,"formalizes":[{"title":"Grothendieck's theorem for Bessel sequences","identifier":"arXiv:2608.12280v1","relationship":"formalizes"}]}