Saturday, 15 July 2017

dunkle materie

In the 1930s Swiss astrophysicist Fritz Zwicky (building upon some significant antecedents with Lord Kelvin measurements and Henri Poincaré’s matiére obscure) accounted for the exponentially different observed velocity of the galactic clusters he was watching due to the presence of some “dunkle Materie.” Consistent but predictable discrepancies in similar measurements over the intervening decades had persuaded science that there was there was a mysterious form of matter that comprised most of the substance of the Cosmos, which was conveniently allusive and unobservable was necessarily for how we understood the Universe to work—which does sound a bit forced.
Justin Khoury, a professor of theoretical physics at the University of Pennsylvania, proffers a new way of understanding dark matter that while not substituting it for the classic idea of æther, a pervading continuum, does invite us to imagine dark matter as not particular or cloud-like (exclusively, at least) but something more fluid in nature. Specifically, we’re to think of dark matter like something called a Bose Einstein Condensate, an exotic state of matter that takes on the quantum property of superfludity. Some particles (and we can only create it in the laboratory under temporary, microscopic conditions) that make up the matrix take on the properties of losing all viscosity—like a super-conductor having no resistance to current—and at the same time other particles retain the sort of fluid dynamics that we are used to. Though we are most comfortable with witnessing or being baffled by quantum weirdness on very small scales, perhaps dark matter and dark energy are macroscopic manifestations of quantum effects at close-range—say just beyond the limits of human reach—and frictionless and virtually undetectable but stretching across vast distances of time and space, dark matter forms pools on galactic-scales that can be seen to influence the way clusters of galaxies and super-structures interact and hold stable. Some hold that dark matter is no better than superstitious preserving appearances—but to abandon it would mean modifying General Relativity—which like the quantum question of scale, has been demonstrated to work very well in our own solar system but remains not so rigorously tested in grander schemes.