Thursday, 13 May 2010
Mirror Matter is an alternative dark matter candidate, in which a second copy of the all the known matter particles in universe, is also present in the universe, and provides the missing mass of the universe. I've recently written about some tentative experiment evidence of mirror matter. But although experiment rules in science, in physics, good mathematically justification for a theory, also seems to count for all lot. Previously Mirror Matter is justified because it restores the symmetry between left handed and right handed particles but why should a symmetry switching handedness of a particle, form a completely right handed different particle, is not obvious. However a recently paper, show this does indeed happen. It investigates the symmetry between left handed spin 1/2 particles, described by a mathematical object known as a spinor, in Matej Pavsic's new paper, he shows that using the Clifford Algebra CL(1,3), a symmetry operation from a left-handed standard model particle, indeed forms a mirror matter right-handed particle, and not a standard model right-handed particle. So mirror matter now has some solid mathematically justification between it. Warning you'll need to understand spinor maths and clifford algebra to understand the paper.
Posted by Dr BDO Adams at 22:41
Sunday, 9 May 2010
The Xenon 100 experiment is a brand new dark matter experiment, with as you might expect a 100 kilograms of Xenon fluid, at the bottom of an old mine, Gran Sasso laboratory in Italy. This is so much bigger than previous experiments that just 11 days of data, are supposed enough to rule out previous positive signals at CDMS, DAMA and CoGeNT. Contraversally this was supposed to be true, even at the lower end of the mass range for dark matter particles, which traditionally detectors with heavy elements (like Xenon) are not so sensitive to. Because Xenon experiment is so new some have worried that it isn't well calibrated yet, so Xenons first result has been high controversial. More on the Xenon experiment from around the web.
Posted by Dr BDO Adams at 12:09