tag:blogger.com,1999:blog-4900998653115227355.post6701690277336405531..comments2023-09-24T09:18:08.695+02:00Comments on What the Hedgehog Sang: The origin of spinHenning Makholmhttp://www.blogger.com/profile/16299831550580392748noreply@blogger.comBlogger2125tag:blogger.com,1999:blog-4900998653115227355.post-58281271750170374712014-06-24T22:34:14.291+02:002014-06-24T22:34:14.291+02:00I just stumbled upon this. although it's a few...I just stumbled upon this. although it's a few years old already, let me say that you rediscovered the concept of a universal covering group. Your group G_spun is precisely the construction of a universal covering group of a Lie group. Your statement is thus that SU(2) is the universal covering group of SO(3) (which is, of course, absolutely correct).Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-4900998653115227355.post-16380195106544254492008-11-28T14:51:00.000+01:002008-11-28T14:51:00.000+01:00I believe is much more easy than you think.First a...I believe is much more easy than you think.<BR/>First at all. Definition of Complex number:<BR/>They are numbers that they do not exist in our real world, however without them algebra is not complete. (This is the fundamental theorem of algebra).<BR/>Physicians does not believe in complex numbers although they used them, because they can not see or measure them. All observables in physics have to be real. ThatÂ´s why the wave function in Quantum Mechanics has no physical meaning. Only if you multiply by its conjugate wich is real, is interpreted as an observable, the probability to find a particle in some place and in some moment.<BR/>Now I suggest to think in spin as a quantity wich is represented in time by a complex number, ie by the function exp(iwt). This time dependent function is complex for all t except at two points where it is a real function. This function is a time rotation about imaginary edge clokwise. If you are a physician you only can measure the value of the spin when is real. A value up (or positive)and a value down (or negative).<BR/>But also por any physician this function is completely equivalent to exp(-iwt)wich is a time rotation counterclockwise. They only can measure two points corresponding to up and down spin.<BR/>For what reason nobody thinks about this possibility? From my point of view is clear.<BR/>Because if you consider this possibility and because the origin of spin is due to an action of a magnetic field, then the evolution in time of magnetic field have to be considered also to be described by a complex function. And If this could happen, then the time evolution of electric field must also be a complex function.<BR/>Do you think could it be possible?<BR/>Pls contact in e-mail address<BR/>angeldeleito@esdoni.e.telefonica.netAnonymousnoreply@blogger.com