Arrow of Time
in [Physics]
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From: Yousuf Khan on 25 Jun 2010 01:41 On 6/25/2010 6:11 AM, bert wrote: > Observers can have different perspectives of time. That has been > confirmed. Best to keep in mind the effects of SR depends upon how > fast one moves. We must always have "time dilation" and Lorentz > contraction in our thinking Stuff is not "absolute" iF eINSTEIN > DID not merge space and time I know I would have. They are two sides > to the same coin. Always got a kick out of this fact. No matter how > fast you chase after a light beam it still retreats from you at c > Photons never change speed nor do they bounce. My "Spin is in theory" > covers this. TreBert As far as I am concerned, the speed of light is simply the speed at which our universe itself is traveling through the time dimension. Anything that is traveling at the speed of light within the universe, is actually just running backwards to stay put in one spot in time, while the universe runs past it; like holding on for dear life onto the bank of a fast-moving river. That would also explain why causal time stops when traveling at exactly the speed of light. If everything traveled at the speed of light, then causality would stop because everything would stay put in their own given spots in time, neither advancing nor retreating. With no movement, no particles would be able to collide and therefore react to each other. If on the other hand, you were traveling at 99.9% the speed of light, then causal time will have slowed down considerably for you; but you are not yet at 100% light speed, so you will still experience reactions, albeit at a much reduced rate. That which we call time dilation is just fewer reactions occurring at a time. You need something traveling slight faster or slower through time to catch up with you and react with you. At 99.9% light speed, there is still a differential range of speeds of 0.1% light speed to play around in. Even if you were at 99.99% light speed, then you still have 0.01% to play around with. It's only when you get to a full 100% light speed that you got 0% differential to play with. Yousuf Khan
From: Sam Wormley on 27 Jun 2010 01:27 On 6/23/10 10:01 PM, Robert L. Oldershaw wrote: > Can you specify any physical system undergoing any specific physical > interaction that violates causality. http://www.spaceandmotion.com/Wolff-Feynman-QED.htm "Abstract. Lack of knowledge of energy transfer between particles is a major obstacle in understanding physics, matter, and the Universe. In 1945 Wheeler and Feynman sought the mechanism of energy transfer by calculating e-m radiation from an accelerated electron. The electron generated outward and inward waves and evoked a response of the universe from absorber charges. This paper compares Wheeler and Feynman�s work with a rigorous solution using the scalar wave equation that finds a quantum-wave electron structure based upon two fundamental principles of Nature. This is equivalent to replacing the material point electron with a spherical quantum-wave electron, a new structure in main-stream thinking but fulfilling a proposal by Schroedinger. Surprisingly, all the natural laws are found embedded in the wave structure of the electron � as envisioned by Schroedinger". "There is no causality violation because the in-waves are real and do not run backwards in time".
From: Edward Green on 27 Jun 2010 15:27 On Jun 19, 11:58 am, "Robert L. Oldershaw" <rlolders...(a)amherst.edu> wrote: > An interesting discussion has started at sci.physics.research > concerning the nature of the "arrow of time" > > Below are the original post and a follow-up. Check it out and > contribute! > -------------------------------------------------------- <...> My incredibly profound view of the arrow of time is that "stuff happens". The second law based arrow confirms rather than overcomes this, since a system started in a purely random state will, according to the microscopic laws of motion, attain a _more_ random state winding the clock either forward or backward. The fact that we don't observe this is a result of an improbable boundary condition after which, well, stuff happened. I'm at least halfway serious. I think time is a primitive. BTW, the microscopic reversibility (if such it be) is a red herring: we might as well ask why peacocks have multiple colored tails and yet there is an arrow of time. Even if we _did_ have microscopically irreversible laws, we likely would have the increase in entropy going either direction from a starting state chosen at random. Again we would come back to the non-random nature of the current state, and its dependence on a highly ordered boundary condition, after which, stuff happened.
From: Yousuf Khan on 29 Jun 2010 04:45 On 6/28/2010 1:27 AM, Edward Green wrote: > My incredibly profound view of the arrow of time is that "stuff > happens". > > The second law based arrow confirms rather than overcomes this, since > a system started in a purely random state will, according to the > microscopic laws of motion, attain a _more_ random state winding the > clock either forward or backward. The fact that we don't observe this > is a result of an improbable boundary condition after which, well, > stuff happened. I'm at least halfway serious. I think time is a > primitive. BTW, the microscopic reversibility (if such it be) is a > red herring: we might as well ask why peacocks have multiple colored > tails and yet there is an arrow of time. Even if we _did_ have > microscopically irreversible laws, we likely would have the increase > in entropy going either direction from a starting state chosen at > random. Again we would come back to the non-random nature of the > current state, and its dependence on a highly ordered boundary > condition, after which, stuff happened. > Sean Carroll has proposal where he says that there was a universe before our current universe, but it was a static universe, with nothing but random fluctuations. Stuff would happen in it, and then unhappen just as easily. He proposes that our current universe happened as a random fluctuation that just gathered steam and grew and grew. Random fluctuations in this new universe have a directional bias, and stuff doesn't unhappen quite as easily. What Is Time? One Physicist Hunts for the Ultimate Theory | Wired Science | Wired.com http://www.wired.com/wiredscience/2010/02/what-is-time/ Yousuf Khan
From: Robert L. Oldershaw on 29 Jun 2010 15:37
On Jun 29, 4:45 am, Yousuf Khan <bbb...(a)spammenot.yahoo.com> wrote: > > Sean Carroll has proposal where he says that there was a universe before > our current universe, but it was a static universe, with nothing but > random fluctuations. Stuff would happen in it, and then unhappen just as > easily. > > He proposes that our current universe happened as a random fluctuation > that just gathered steam and grew and grew. Random fluctuations in this > new universe have a directional bias, and stuff doesn't unhappen quite > as easily. > ---------------------------------------------------------- Oh, fer shur man! Like....WOWWW! Or you could say that causality rather than time determines the sequence of events in nature, and skip Mr. Carroll's fantasies about multiverses, extra-dimensions, and the Big Bang preventing our eggs from unscrambling. I grant that his hand-waving arguments are creative, but they are also completely nuts. RLO www.amherst.edu/~rloldershaw |