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NowThatWeKnow

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Everything posted by NowThatWeKnow

  1. Martin is the expert and I am far from one but I would like to comment on a couple of things you said. The z=1090 I used in the morgan calculator took us back to the big bang when it was thought the expansion was at it's greatest. http://www.uni.edu/morgans/ajjar/Cosmology/cosmos.html It very quickly fell off to a much lower speed when the universe was still starless dust and not transparent. I think the largest Redshift seen now is 8.2. Play with the calculator to get a feel for how they think it all went down. I agree with you that the jury is still out. I am not sure exactly how they use the cosmological red shift to determine expansion speed but there are a couple of different methods to cross check the results. The duration of an initial bright phase of a supernova is also used to determine distance and expansion. I often thought that light itself could be the energy responsible for the universe expansion but I have been told there is not enough energy there to produce the results we observe. It made more sense to me then dark energy/matter that we can not detect except for the results it produces. Almost like saying God did it. I will also not be surprised if there is a, yet to be defined, ether discovered with light playing some role.
  2. Our thought experiments have unlimited technology. The master clock is hooked to CMB speedometer and gravitonometer to stay synchronized to Earth time. The GPS satellites are synchronized to Earth clocks so it isn't impossible.
  3. But that is why we have a master clock. So we do not have to wait for the time of transmission. Just because we see the lightning before we hear the thunder does not mean they were not simultaneous or synchronized.
  4. I do not see where swansont is backwards. A lot has been said (repeated) and you should use quotes around the text you are talking about. What you are thinking may be clear in your mind but not to the rest off us.
  5. The space mans frame is his rocket ship and all that is in it. It all looks normal to him. He is not hurt. When the space man looks out the window, he is looking at a different frame that is contracted from ONLY his point off view. Edit - I think your problem is where to place the borders of each frame.
  6. How can all that be true? It sounds like a contradiction. I gave the two twins a master clock slaved to Earth's time frame and can not see how they would differ. And I thought I had those d@mned twins figured out.
  7. I know that many will argue that length contraction is not an illusion but maybe the distorted mirror may be the best way for some to look at it.
  8. I asked this in a thread in the relativity forum and it got buried and never got answered. Does the separation of matter caused by the expansion of space experience the same time dilation and length contraction as a similar distance change and speed from a rocket ride? I am thinking that if two galaxies are at rest with the CMB but are separating at relativistic speeds due to a increase in distance from expansion, they will share the same time frame. I am thinking that if the two twins blasted off from Earth experiencing equal acceleration but in opposite directions, They also would experience the same time frame. Despite there increasing separation speed. Anyone have the answer and where am I going wrong?
  9. Can you believe all the mind power necessary to come up with the knowledge to make this calculator accurate, and I had a typo that made it all worthless. Well I fixed it. I will PM you.
  10. I had a couple of extra minutes. Edit - Fixed typo on attached image.
  11. Neither am I. Hence, my screen name. In actuality we don't know $h!t. Knowledge is changing quickly and that should continue. I suspect we will never be able to say "NowThatWeKnow". So, I am just attempting to relay what I think is mainstream today. Knowing that much of it will change tomorrow. As the balloon expands the distance between every dot (qalaxy) increases. Each specified distance will expand equally in all directions. The further the distance, the faster the speed. There is no center to the surface of the balloon. Light is sent out as a continuous beam over billions of years and not just a flash to be monitored at a particular time. As the distance of two objects separating increases, the light will redshift until it can no longer be seen. Just a few of my thought addressing what I think you were saying.
  12. Sysyphus and swansont, The ladder paradox is interesting, I will try to think of a way my "master clocks" can simplify it. It seems I was confusing comparing different frames to mixing different frames. Sometimes I am not sure where to put that line. I wasn't thinking of minute particles everywhere traveling a high speeds relative to us and of course the particle accelerators where we can observe the results of relativistic speeds. This has been an educational thread for me and your tolerance to physics ignorance is admirable. Thank you. Now, on to the next problem. Does the separation of matter caused by the expansion of space and the movement through space relative to us, such as a rocket, both experience the same time dilation and length contraction from Earth's point of view?
  13. This is mentioned a few times in this thread but afaik the only frames moving at relativistic speeds relative to Earth are because of the expansion of space and not motion. This brings us back to my question in the last paragraph in post 23. Unless we can say for sure that speed from space expansion causes time dilatation and length contraction and not just motion through space, should we use it as an example to prove a point? Last plug for my cause. I will start a new thread if it isn't resolved.
  14. If the light from a galaxy took 13.66 billion light years (almost the age of universe) to get here, it was emitted when it was 0.205525 billion light years away and is now 43.762 billion light years away. This is not because of the movement of galaxies but because of the expansion of space. The universe was more dense long ago but the big bang is currently looked at as not coming from a singularity. At the edge of the observable universe we would probably see a similar view in every direction as we do from the Milky Way.
  15. I remember him saying "observable universe concentrated in volume the size of an atom," To the layman that sounds like singularity. Good video but not pushing the agenda of this thread.
  16. Watch the Wright Balloon video as Martin suggested. A picture is worth a thousand words. Also, if you can visualize a balloon slowly filling up with air and the balloon has dots (dots are galaxies) all over it. No matter what dot you are on, all other dots are moving sway from you. The further away the dot is the faster it is moving away. Space is expanding between each dot. There is no center on the surface of the balloon and every location will yield the same view. Now put an ant on the balloon (Not sure why I use ants). Say his movement represents the speed of light. He can easily get to the dots near by but if the balloon is expanding fast his speed may not be enough to get to dots far away. I am tired of typing. Go watch the short video. Edit - http://www.astro.ucla.edu/~wright/Balloon2.html
  17. I started a thread once called "Is relativistic mass an illusion" and got varied responses. What you observe from different frames will vary but no matter what frame your are in, 1' is 1' and you can not mix frames as you are suggesting above. I do agree the mirror may not have been the best analogy. Yes, motion relative to the CMB was not a good example but at that moment it seemed right since galaxies are basically at rest with the CMB despite separating at relativistic speeds. Martin said any one at rest with the CMB, any where in the universe, would calculate the age of the universe the same. That indicates to me that there is no time dilation between separating galaxies (with the same background temperature). I would like someone with more knowledge then me to chime in here..................Please Maybe the uniform expansion is acceleration equal in all directions with time dilatation being equal accross the universe. Hang on, time is slowing down and will soon stop.
  18. Time has already been defined http://en.wikipedia.org/wiki/Time Everyone must use the same definition of time or we have mass confusion, and we do not need any more confusion.
  19. Thank you for elaborating. I was trying to keep it simple and thinking of synchronized clocks in different frames as analogue hands moving over the same numbers simultaneously with no regard to how it was done. Merged post follows: Consecutive posts merged Sometimes I think we are looking at the same thing from different angles and then arguing with ourselves. As far as "Master Clocks", swansont has convinced me to use it, at least until something better is suggested.
  20. You make an excellent point and I have been converted. If there is some reason to use the words "universal time" in the future, I will define it. Merged post follows: Consecutive posts merged A consistent background temperature in all directions will put you at rest with the CMB. Gravity will also have to be considered but it will help eliminate time dilation and length contraction issues when looking at simultaneous events. At Least that is the way I see it. I like your examples. Edit - I started to elaborate but seem to be brain dead at the moment.
  21. If you look in a distorted mirror you will look distorted but it doesn't mean you are distorted. It does not shrink. This brings up another question. I know there is red shift because of the expansion of space, but is there time dilation and length contraction because of the expansion of space? Or is time dilation and length contraction only caused by movement relative to the CMB. If the expansion of space does cause time dilation, what is time doing in galaxies so far away they are separating at MORE then the speed of light?
  22. The speed of a clock could be synchronized without the time being synchronized (in the same frame), right? I think you are saying that the GPS satellite clocks are synchronized to Earth clocks but running at different speeds and in different frames. Is that right?
  23. I thought you had read about the relativistic rocket at http://math.ucr.edu/home/baez/physics/Relativity/SR/rocket.html The Andromeda galaxy is only 28 years away at 1G acceleration. One year at 1G will put you at .77c. And you can let the calculators do all the math for you. http://www.cthreepo.com/math1.shtml
  24. I almost said that but I know he does know it because he used it earlier to support his argument.
  25. No, not any more then it would matter to you right here, right now. You are both at rest in your own frame.
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