In new research that has been presented at seminars and is under review by the Monthly Notices of the Royal Astronomical Society, a team of Dutch astronomers have conducted what they call the first test of Verlinde’s theory: In comparing his formulas to data from more than 30,000 galaxies, Margot Brouwer of Leiden University in the Netherlands and her colleagues found that Verlinde correctly predicts the gravitational distortion or “lensing” of light from the galaxies - another phenomenon that is normally attributed to dark matter. With such a tight relationship between gravity felt by visible matter and gravity given by visible matter, there would seem to be no room, or need, for dark matter.Įven as dark matter proponents rise to its defense, a third challenge has materialized. Remarkably, these two variables were tightly linked in all the galaxies by a universal law, dubbed the “radial acceleration relation.” This makes perfect sense in the MOND paradigm, since visible matter is the exclusive source of the gravity driving the galaxy’s rotation (even if that gravity does not take the form prescribed by Newton or Einstein). The researchers analyzed a diverse set of 153 galaxies, and for each one they compared the rotation speed of visible matter at any given distance from the galaxy’s center with the amount of visible matter contained within that galactic radius. 9 in Physical Review Letters, three astrophysicists led by Stacy McGaugh of Case Western Reserve University in Cleveland, Ohio, have strengthened MOND’s case against dark matter. In a new analysis of galaxies published on Nov. While it remains to be seen whether his arguments will hold up to scrutiny, the timing is fortuitous. Many experts have called Verlinde’s paper compelling but hard to follow. “I have a way of understanding the MOND success from a more fundamental perspective,” Verlinde said. That this ugly fix works at all has long puzzled physicists. This 30-year-old theory makes an ad hoc tweak to the famous “inverse-square” law of gravity in Newton’s and Einstein’s theories in order to explain some of the phenomena attributed to dark matter. In his calculations, Verlinde rediscovered the equations of “modified Newtonian dynamics,” or MOND. On large scales in the hologram, he argues, dark energy interacts with matter in just the right way to create the illusion of dark matter. Working within this framework, Verlinde traces dark energy to a property of these underlying qubits that supposedly encode the universe. Space-time and the matter within it are treated as a hologram that arises from an underlying network of quantum bits (called “qubits”), much as the three-dimensional environment of a computer game is encoded in classical bits on a silicon chip. According to the new approach, gravity is an emergent phenomenon. Einstein defined gravity as the effect of curves in space-time created by the presence of matter. To make his case, Verlinde has adopted a radical perspective on the origin of gravity that is currently in vogue among leading theoretical physicists. Instead of hordes of invisible particles, “dark matter is an interplay between ordinary matter and dark energy,” Verlinde said.
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