tag:blogger.com,1999:blog-8666091.post758599466380197689..comments2021-04-15T06:42:27.872+02:00Comments on The Reference Frame: Fermi kills all Lorentz-violating theoriesLuboš Motlhttp://www.blogger.com/profile/17487263983247488359noreply@blogger.comBlogger9125tag:blogger.com,1999:blog-8666091.post-73700520089335088102012-12-19T18:54:15.634+01:002012-12-19T18:54:15.634+01:00mr.lubos.in quantic scale,the speed of light is li...mr.lubos.in quantic scale,the speed of light is linked to<br /><br />frequency of colors,this is at planck scale level the speed of light is proportional to its frequency( colors).<br /><br />then the the invariance of lotentz could be broken,and restaured by the quantum topological field theory,that contain the noncommmutative topological geometrics<br />as sets of subspacetimes as renormalization of invariance of lorentz to the local quantics theories ( the hidden variables or hidden dimensions appear through<br />cp or pt spontaneous symmetry breaking)Rosy Motahttp://www.facebook.com/people/Rosy-Mota/100000985575131noreply@blogger.comtag:blogger.com,1999:blog-8666091.post-88567886463195771932012-12-16T20:03:38.724+01:002012-12-16T20:03:38.724+01:00each "particles" must vibrate in frequen...each "particles" must vibrate in frequency only one.this,in the spacetime given by two curvatures of spacetime opposed that if connect.Rosy Motahttp://www.facebook.com/people/Rosy-Mota/100000985575131noreply@blogger.comtag:blogger.com,1999:blog-8666091.post-30721797943660757962012-12-16T19:56:26.706+01:002012-12-16T19:56:26.706+01:00is interesting that the invariance of lorentz( poi...is interesting that the invariance of lorentz( poincare's complete group) introduces the speed of light as limit and constant speed (not as intrinsec property of the nature ) is due the PT symmetry breaking that implies in the connection of space and time into 4-dimensional spacetime continuos,each one with one value of speed of light.the violation of invariance of lorentz is renormalized by the existence of antiparticles-as reversal PT- have that the non invariance of left-right handed rotational systems-implies in the time dilatation and contraction of space.but the conjugation of charge<br />in the case remain conserved in the variations of spacetime with the incresement of velocity<br />i think that the antimatter doesn't exist in the universe,and the antiparticles are due the asymmetry of spacetime given by the transformation of energy in mass and viceversa with the increse of velocity.Rosy Motahttp://www.facebook.com/people/Rosy-Mota/100000985575131noreply@blogger.comtag:blogger.com,1999:blog-8666091.post-11907742151302434752012-05-03T08:37:26.044+02:002012-05-03T08:37:26.044+02:00It is of course true that any viable quantum theor...It is of course true that any viable quantum theory of gravity needs to agree with general relativity where general relativity has been tested. Claims to the vastness of the domain where general relativity rings true are, in a strict sense, however, exaggerated. Specifically, this domain is commonly claimed to span at least over scales such as the solar system and the weak gravitational fields found therein.<br /><br />For certain historical, practical, and other reasons, a large sub-domain within the solar system has been neglected. Almost everything we know about gravity derives from observations of gravitational phenomena over the surfaces of large gravitating bodies. What is completely unknown is how test objects move inside and near the centers of gravitating bodies.<br /><br />The classic example is the simple harmonic motion of a test object dropped into a hole through a uniformly dense spherical mass. But this is just a prediction, not an empirical fact. There is no direct empirical support for this prediction, which, in terms of general relativity, corresponds to a pattern of clock rate differences inside matter, where the rate of a clock at the center is a local minimum.<br /><br />The presumed attractive nature of gravity and the energy conservation law may well give us confidence to pretend that we know how things fall near the centers of large bodies. But in fact we do not. Once acknowledged as such, we could look upon this actual gap in our empirical knowledge of gravity as an opportunity to test and confirm that the attractive nature of gravity and the energy conservation law do indeed hold true.<br /><br />In other words, we could continue to presume that the Schwarzschild interior solution and the Newtonian counterpart are correct, or we could be thorough scientists and test them. Especially given the controversy over the true nature and role of gravity in the physical world, as often discussed in this blog, it behooves us as thorough investigators to not leave unturned the stone of gravity-induced radial motion without collision.<br /><br />In practical terms, this could be done with a modified Cavendish balance in an Earth-based laboratory for a fraction of the cost of many other gravity experiments that look for much smaller effects.Benishhttps://www.blogger.com/profile/18189267158453096769noreply@blogger.comtag:blogger.com,1999:blog-8666091.post-40776445990980788982011-12-03T05:00:35.579+01:002011-12-03T05:00:35.579+01:00So basically, unless you can find another theory o...So basically, unless you can find another theory of quantum gravity that maintains exact local Lorentz symmetry and produces the correct continuum limit of general relativity, there's no game in town except string theory.<br /><br />It would be nice if we could assume the following three things:<br /><br />1. The laws of quantum theory are correct.<br /><br />2. SO(d-1,1) is an exact symmetry of nature.<br /><br />3. General relativity is exact in the limit hbar -> 0.<br /><br />And then show from those assumptions alone that string theory necessarily follows. I'm not aware that any such proof exists, but then again, I'm still in the process of learning quantum field theory.unhealthytruthseekerhttps://www.blogger.com/profile/16260828701931057781noreply@blogger.comtag:blogger.com,1999:blog-8666091.post-50792818468081698252010-11-01T07:42:55.415+01:002010-11-01T07:42:55.415+01:00By the way, while this blog entry about Fermi and ...By the way, while this blog entry about Fermi and Lorentz symmetry is not quite about holography, it's actually an extremely sensible place to discuss this issue of Hogan's noise.<br /><br />Fermi has also falsified theories in which a short-distance effect is supposed to be inflated proportionally at very long distances and time separation.<br /><br />No such effects exist - whether they would be about Lorentz violation or "noise" resulting from the holographic principle. Any such effect would make the Wick rotation etc. inconsistent. It is very important that the events that are separated by light-like intervals are "very close" - by the most physical measure called the proper distance/time. <br /><br />All physical laws must therefore accept the special character of the speed of light, and not even add any "noise" to it, because any deviation would mean that vanishing distances (light-like intervals, after analytical continuation to the Euclidean space) are pretty much equivalent to arbitrarily long separations, which would distort locality at macroscopic scales. <br /><br />I think it's impossible in general. At any rate, it's impossible in Hogan's picture because the "noise" he "derived" was actually put in, by his not having made the calculation of the evolution accurately. But Nature and laser interferometers *will* do their job accurately and they will show there's no such noise. ;-)<br /><br />Cheers<br />LMLuboš Motlhttps://www.blogger.com/profile/17487263983247488359noreply@blogger.comtag:blogger.com,1999:blog-8666091.post-40775983464362249022010-11-01T07:33:41.205+01:002010-11-01T07:33:41.205+01:00Dear Mitchell,
good points. I actually made a som...Dear Mitchell,<br /><br />good points. I actually made a <a href="http://motls.blogspot.com/2007/06/gr-qc-papers-on-friday.html" rel="nofollow">somewhat positive</a> comment about Hogan's ideas back in 2007.<br /><br />Now I think they're wrong. The holographic principle can't induce effects that grow proportionally to the separation between various effects in space or time.<br /><br />Hogan may have psychological uncertainty about the position of events in space and time but Nature doesn't share this uncertainty. ;-)<br /><br />Nothing like that follows from Matrix theory. In this case, I think it's completely obvious that spacetime at distances and times much longer than the Planck scale is clearly behaving classically and ordinary quantum mechanics allows one to define the velocities exactly etc. Matrix theory only makes the internal structure of objects non-commutative.<br /><br />Holography only has very subtle effects on phenomena and it's likely that no effect of quantum gravity's holography may be observed by existing apparata.<br /><br />Best wishes<br />LubosLuboš Motlhttps://www.blogger.com/profile/17487263983247488359noreply@blogger.comtag:blogger.com,1999:blog-8666091.post-21400959732871993782010-11-01T06:59:48.966+01:002010-11-01T06:59:48.966+01:00Hi Lubos - there are some reports recently about a...Hi Lubos - there are some reports recently about an experiment to measure so-called "holographic noise" via laser interferometry. The "holographic noise" is supposed to arise from quantized space, and the author even has <a href="http://arxiv.org/abs/0812.1285" rel="nofollow">a paper</a> where he and a coauthor claim to calculate the magnitude of holographic noise predicted by Matrix theory! Just on the sociological criteria like citations (almost none except for self-citations) and attention from string theorists (none), it sounds like another wrong idea (I was reminded of DSR). I made a comment at <a href="http://talkislam.info/2010/10/29/since-im-currently-banned-at-tas-again/#comment-34910" rel="nofollow">a random blog</a> explaining all this, but I thought I would mention it here as well.Mitchellhttps://www.blogger.com/profile/10768655514143252049noreply@blogger.comtag:blogger.com,1999:blog-8666091.post-57952565179270705882009-08-17T22:53:17.567+02:002009-08-17T22:53:17.567+02:00Well, Lubos, I must admit, I tried for years to re...Well, Lubos, I must admit, I tried for years to reconcile quantum gravity with no strings attached, I fought like mad, but I am at the point where I don't believe it can be done. <br /><br />I'm compelled to retract what I have previously said about string theory, namely that it is just a trick to make solutions of PDE have characteristics dissipate irregularities in higher dimensions if that can't be done in low dimensions. I was wrong.<br /><br />I lose this one.Brian G Valentinehttps://www.blogger.com/profile/01523059818774910427noreply@blogger.com