36grit Posted January 29, 2011 Posted January 29, 2011 If mass is energy moving at twice the speed of light, Wouldn't each and every atom constantly radiate and/or exist in it's own time dialation wave and/or bubble?
insane_alien Posted January 29, 2011 Posted January 29, 2011 well mass isn't energy moving at twice the speed of light so the weirdness after is moot.
alpha2cen Posted January 30, 2011 Posted January 30, 2011 According to general relativity theory anything can not move fast than light speed.
insane_alien Posted January 30, 2011 Posted January 30, 2011 oh no, general relativity does stop anything from going faster than the speed of light, it just sets certain limits on its properties. for instance, it must always have been going faster than light, it will have complex energy and it cannot be made to go slower than the speed of light. to be perfectly accurate, relativity says nothing can accelerate through the speed of light. however, quantum mechanics says that any tachyons would be unstable so that does kind of mean that there are no cool superluminal entities.
alpha2cen Posted January 31, 2011 Posted January 31, 2011 In fact we do not know how fast we are moving. We do not know the fixed point in the Universe. Is the light speed limitation in the relativity theory an observed value at the fixed point in the Universe?
ajb Posted January 31, 2011 Posted January 31, 2011 In fact we do not know how fast we are moving. With respect to what? We do not know the fixed point in the Universe. I am not sure what is meant by this. In cosmology it may be convenient to define the CMB rest frame. You can then discuss things with reference to this frame. It seems a natural frame for cosmology, but it is not a truly preferred frame. All other frames, inertial or not are just as valid. Is the light speed limitation in the relativity theory an observed value at the fixed point in the Universe? What is meant by a fixed point? Some specified point in space-time?
alpha2cen Posted January 31, 2011 Posted January 31, 2011 (edited) What is meant by a fixed point? Some specified point in space-time? We do not know how fast our Galaxy moving at the fixed point which is not moving in the Universe. Where is the fixed point? So we do not know weather we over the speed limit(light velocity) or not. Edited January 31, 2011 by alpha2cen
ajb Posted January 31, 2011 Posted January 31, 2011 The speed limit of c is really a local thing. There is no violation of relativity if we consider objects that are "carried by the expansion". So, we should really be thinking about local things, speed will depend on the coordinates employed. In general relativity one can employ local Riemannian coordinates and the strong equivalence principle. It is because general relativity reduced to special relativity in "small enough regions" we have the local speed limit if c. Thus we need to think about a point "near by" as the "fixed point". If the point is not "near by" then it could be difficult to think about. I.e. if the fixed point is not in the neighbourhood the other points (our Galaxy etc) we wish to study. If that point is out side of the universe, it would make sense to extend out Universe to no longer be connected and include this external point. But this will not be in the neighbourhood of any other points.
36grit Posted February 1, 2011 Author Posted February 1, 2011 Do quantum paritcles move faster than light? It seems to me that if you could exist in two or more places at the same time, and quantum leap from here to anywhere, that you could easily out run light.
ajb Posted February 1, 2011 Posted February 1, 2011 (edited) Do quantum paritcles move faster than light? It seems to me that if you could exist in two or more places at the same time, and quantum leap from here to anywhere, that you could easily out run light. So, quantum mechanically a particle can tunnel through a potential barrier that it could not overcome classically. You can calculate rates of such things and ask if this would allow faster than light travel. It turns out that this can be less than the time taken for a photon to traverse that distance. The question really is can information be transmitted in this way. The answer must be no. If not then QED will have serious problems. There are some experiments performed to test exactly this [1]. It has been claimed that this could allow faster than light communications. The interpretation is very controversial and probably really due to the uncertainty principle rather than faster than light communication. Virtual particles can also not be used for faster than light communication. References [1] W. Heitmann and G. Nimtz, Phys Lett A196, 154 (1994); A. Enders and G. Nimtz, Phys Rev E48, 632 (1993) Edited February 1, 2011 by ajb 1
36grit Posted February 2, 2011 Author Posted February 2, 2011 Back to the subject matter, time dialation and matter. accepted theory 1) Every action has an equal and opposite reaction " 2) Relativity unifies space and time " 3) If velocity on a plane exceeds the speed of light, a time dialation will be experienced between the entitiies exceeding the limit, and distance will appear to on outside observer to close or expand faster than light " 4) The doppler affect is caused by waves stretching or compressing. light from a distant galaxie can appear red and blue at the same time by two different observers What is the equal and oppisite reaction that occurs during a time dialation? Is it possible that time could convert into distance?
ajb Posted February 3, 2011 Posted February 3, 2011 Every action has an equal and opposite reaction What is the equal and oppisite reaction that occurs during a time dialation? In special relativity you are normally considering particles that are not being acted upon by external forces. The particles are travelling at a constant speed relative to any inertial observer. Or more correctly for us, we have time dilation even when particles are not being accelerated. So I don't understand your question, which seems very Newtonian. Is it possible that time could convert into distance? If we understand space and time to be a "single entity" of space-time then the above question is not well-formulated. We have have no way of uniquely separating space-time into space and time. We will always have to consider transformations, the Lorentz transformations which mix space and time.
36grit Posted February 9, 2011 Author Posted February 9, 2011 If we understand space and time to be a "single entity" of space-time then the above question is not well-formulated. We have have no way of uniquely separating space-time into space and time. We will always have to consider transformations, the Lorentz transformations which mix space and time. I guess what I'm asking is, if time slows down wouldn't space expand? If it speeds up wouldn't space thin? or perhaps, if time dialates in a certain region, wouldn't that region of distance also become distorted? Perhaps a slightly densor region of space?
ajb Posted February 9, 2011 Posted February 9, 2011 I guess what I'm asking is, if time slows down wouldn't space expand? If it speeds up wouldn't space thin? or perhaps, if time dialates in a certain region, wouldn't that region of distance also become distorted? Perhaps a slightly densor region of space? Sort of. The invariant quantify associated with a path (i.e. motion) is the space-time interval. In short [math]ds^{2} = g_{\mu\nu} dx^{\nu} dx^{\mu}[/math] is invariant, that is all observers will agree on this. So, in special relativity, say in 1+1 dimensions the quantity [math]dx^{2}-dt^{2}[/math] is invariant (there are conventions about signs that won't matter at all here). So, generally observers will not agree on [math]dx[/math] or [math]dt[/math], but they will always agree on the space-time interval. So in this respect what you have said is OK.
IM Egdall Posted February 10, 2011 Posted February 10, 2011 There is a connection between motion through time and motion through space. Let's choose a frame of reference, say your chair. If you are sitting in your chair, you are at rest relative to the chair. So relative to the chair, there is no time dilation, no slowing of time on your watch. Thus you are moving through time as fast as you can! Say you get up and move relative to the chair. Now from the chair's point of view, you are moving through space. So from the chair's point of view, your watch runs slower due to time dilation. And the faster you move through space, the more time dilation or the slower you move through time. Thus there is a kind of sharing between space and time, The more you move though space, the less you move through time. And vice versa.
swansont Posted February 15, 2011 Posted February 15, 2011 ! Moderator Note Time frame speculation has been moved to speculations http://www.scienceforums.net/topic/54885-time-frame-hypothesis/
lemur Posted February 15, 2011 Posted February 15, 2011 So, quantum mechanically a particle can tunnel through a potential barrier that it could not overcome classically. You can calculate rates of such things and ask if this would allow faster than light travel. It turns out that this can be less than the time taken for a photon to traverse that distance. The question really is can information be transmitted in this way. Even if an electron can exceed the speed of light, how could its interaction with other electrons ever exceed C when EM force is the medium for interaction between electrons?
ajb Posted February 16, 2011 Posted February 16, 2011 Even if an electron can exceed the speed of light, how could its interaction with other electrons ever exceed C when EM force is the medium for interaction between electrons? Are you asking if virtual photons are constrained to travel at c? Virtual photons can travel faster than c. However, they are really a mathematical tool and so do not violate relativity.
steevey Posted February 16, 2011 Posted February 16, 2011 (edited) According to general relativity theory anything can not move fast than light speed. But in quantum mechanics, the determination of entanglement as well as the entangled properties responding to one another occur instantaneously, or in other words, infinite speed, which is faster than light for some reason. Although, there's probably some way to explain it in relativity. Are you asking if virtual photons are constrained to travel at c? Virtual photons can travel faster than c. However, they are really a mathematical tool and so do not violate relativity. When things pop in and out of existence, are they actually traveling distance, or are they just appearing as a single point where their wave is existing throughout space infinitely? Edited February 16, 2011 by steevey
Xerxes Posted February 16, 2011 Posted February 16, 2011 The invariant quantify associated with a path (i.e. motion) is the space-time interval. In short [math]ds^{2} = g_{\mu\nu} dx^{\nu} dx^{\mu}[/math] is invariant, that is all observers will agree on this. This is how it is usually presented, and I have no quarrel with it. BUT...... ....it might help to explain what is the factor (if that's what it is) [math]g_{\mu\nu}[/math], whether we are multiplying or summing, what are the [math]\{x^i\}[/math], and what would be the consequence of setting [math]x^{\mu} = x^{\nu}[/math]. Of course, I can give chapter and verse, but it would be a very long haul, of little interest to physicists let alone "protophyicists"
ajb Posted February 19, 2011 Posted February 19, 2011 ....it might help to explain what is the factor (if that's what it is) [math]g_{\mu\nu}[/math], whether we are multiplying or summing, what are the [math]\{x^i\}[/math], and what would be the consequence of setting [math]x^{\mu} = x^{\nu}[/math]. Of course, I can give chapter and verse, but it would be a very long haul, of little interest to physicists let alone "protophyicists" I am not going to "spoon feed" everyone. I am happy if I have given them enough hints to fill in the gaps themselves.
DrRocket Posted February 19, 2011 Posted February 19, 2011 If that point is out side of the universe, it would make sense to extend out Universe to no longer be connected and include this external point. But this will not be in the neighbourhood of any other points. What would you do with a point in some other connected component of the "universe" ? That idea would pretty well make a hash of general relativity. Once you allow a non-connected manifold in the model you can get just about anything. But the connected component in which we find ourselves is, given the apparent accelerating expansion of "space", already large enough to contain regions that are and will remain causally disconnected from us on or near Earth and the galaxy, and hence consideration of anything larger is rather more philosophical than scientific.
36grit Posted February 21, 2011 Author Posted February 21, 2011 What would you do with a point in some other connected component of the "universe" ? That idea would pretty well make a hash of general relativity. Once you allow a non-connected manifold in the model you can get just about anything. But the connected component in which we find ourselves is, given the apparent accelerating expansion of "space", already large enough to contain regions that are and will remain causally disconnected from us on or near Earth and the galaxy, and hence consideration of anything larger is rather more philosophical than scientific. You could do a lot, if that point existed within the foundation of the universe and yet, was not a part of the universe. A tree is highly dependent on it's foundation but, the foundation it'self can exist perfectly fine without the tree. In fact, some might even say that: With the proper knowledge and understanding of the foundation, we could bring forth a tree with no seed to start from. Just some very percise quantum fluctuations and perhaps a little luck, and some water.
ajb Posted February 22, 2011 Posted February 22, 2011 ... hence consideration of anything larger is rather more philosophical than scientific. Sure, we would never know about it. I agree, more philosophy.
michel123456 Posted February 22, 2011 Posted February 22, 2011 What would you do with a point in some other connected component of the "universe" ? That idea would pretty well make a hash of general relativity. Once you allow a non-connected manifold in the model you can get just about anything. But the connected component in which we find ourselves is, given the apparent accelerating expansion of "space", already large enough to contain regions that are and will remain causally disconnected from us on or near Earth and the galaxy, and hence consideration of anything larger is rather more philosophical than scientific. When you look at a simple Minkowski diagram, you may notice that there are regions of spacetime that are causally diconnected from us while very close. The left & right part of the diagram are evident examples.
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