2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/137711We explain how Polchinski's work on D-branes re-read from a noncommutative version of Grothendieck's equivalence of local geometries and function rings gives rise to an intrinsic prototype definition of D-branes (of B-type) as an Azumaya-type noncommutative space. Several originally open-string induced properties of D-branes can be reproduced solely by this intrinsic definition. We study also the moduli space of D0-branes on a commutative target space in this setup. Some of its features resembles gas of D0-branes in Vafa's work.57 pagesAlgebraic GeometryHigh Energy Physics - TheorySymplectic Geometry14A22, 81T30text