2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/51579Throughout John Wheeler's career, he wrestled with big issues like the fundamental length, the black hole and the unification of quantum mechanics and relativity. In this essay, I argue that solid state physics -- historically the study of silicon, semiconductors and sand grains -- can give surprisingly deep insights into the big questions of the world.A chapter for John Wheeler's 90's birthday festschriftHigh Energy Physics - TheoryStrongly Correlated Electronstext