Dark Matter Might Just Be… Normal Matter.

Quick Overview

Recent theoretical work suggests that dark matter might not be composed of exotic particles, but rather of ordinary matter in the form of stable, massive clumps called strangelets, which are hypothesized objects formed from up, down, and strange quarks.

Key Points: A recent paper argues that dark matter could be composed of strangelets, which are macroscopic clusters of up, down, and strange quarks. Strangelets are hypothesized to be stable and electrically neutral, fitting key requirements for dark matter candidates. Unlike standard matter, which requires the early universe to undergo a first-order phase transition from quark-gluon plasma to hadron gas to form these structures, the proposed strangelet formation is theorized to occur via a crossover transition, which is more favorable. The proposed strangelet dark matter would be extremely heavy, with one grain potentially weighing one ton, and would be so massive that hitting Earth would create tunnels instead of typical impact craters. The Standard Model of Particle Physics is effectively ruled out as the source of dark matter because the known particles (muons, taus, second/third generation quarks, W/Z bosons, Higgs) are either unstable or do not interact electromagnetically. The idea that dark matter is strange quark matter was originally suggested by Ed Witten in 1984 but fell out of favor due to conflicting QCD calculations. The video promotes Incogni, a service for removing personal data from data broker sites, offering a 60% discount with the code SABINE.

Context: The video addresses the long-standing mystery of dark matter, which is thought to constitute about 80% of the universe's mass but does not interact with light or other electromagnetic radiation. Sabine Hossenfelder discusses a recent theoretical reconsideration of an older idea—that dark matter could be composed of strangelets, which are hypothetical stable clumps of up, down, and strange quarks, rather than entirely new, undiscovered particles.