NS: Dark matter could meet its nemesis on Earth
Posted: Mon Mar 01, 2010 6:23 pm
Dark matter could meet its nemesis on Earth
New Scientist - 2010 Mar 01
Testing the Newton second law in the regime of small accelerations - VA De Lorenci, M Faundez-Abans, JP Pereira
New Scientist - 2010 Mar 01
A SPINNING disc may be all that is needed to overturn Newton's second law of motion - and potentially remove the need for dark matter.
The second law states that a force is proportional to an object's mass and its acceleration. But since the 1980s, some physicists have eyed the law with suspicion, arguing that subtle changes to it at extremely small accelerations could explain the observed motion of stars in galaxies.
Stars move at speeds that suggest that galaxies have far more mass than is visible, which astronomers attribute to dark matter. But if Newton's second law could be modified ever so slightly, it would obviate the need for dark matter. The hypothesis, known as modified Newtonian dynamics (MOND), was proposed in 1981 by Mordehai Milgrom, then at Princeton University.
Ground-based tests of MOND had been thought impossible because of the confounding motions of the Earth. But now, Vitorio De Lorenci of the Federal University of Itajubá, Brazil, and colleagues have devised an experiment to do just that (arxiv.org/abs/1002.2766).
Testing the Newton second law in the regime of small accelerations - VA De Lorenci, M Faundez-Abans, JP Pereira
- arXiv.org > gr-qc > arXiv:1002.2766 > 15 Feb 2010