Minkowski Space Time Briefly Revisited

Discussion in 'Physics & Math' started by danshawen, Nov 24, 2014.

  1. OnlyMe Valued Senior Member

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    3,914
    1. You are the only one talking about time flowing. At least in the context it seems you use.
    2. There is no direct connection between optical clock rates and the speed of light.
    3. Whether space is or is not homogeneous or inhomogeneous, requires first a far better description/definition of exactly what you mean by the word space. I think, in context Einstein was referring to spacetime, rather than just space.
    4. Again with the reference to Einstein's Leyden address, which you have repeatedly shown you did not understand. Remember CONTEXT, CONTEXT CONTEXT. That was an address intended for a specific audience, whose background was rooted in the aether theory, preceding century. The ideas Einstein was presenting had not yet made their way into basic undergraduate education. In short, had he known he would be talking to you, he may have kept his mouth shut!
     
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  3. nimbus Registered Senior Member

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  5. nimbus Registered Senior Member

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    Similar lay out, and maybe those letters at top left side "phpBB" when scanned quickly could be mistaken for PMB???
    But that's Shortsight's site. Here's his introduction page...
    http://www.physicsdiscussionforum.org/introduction-t6.html.
    If we don't see you around here in the next few days, we know your hooked.

    He's so scary.
    You can't read the posts there? Your so lucky. I'm no member but can.
     
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  7. PhysBang Valued Senior Member

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    2,422
    So many lies. So much revealed deception.

    You now admit that you were claiming that Sharpiro "wrote what he wrote" without actually having a copy of what he wrote. Great scholarship, Farsight.

    So now we know that nothing you say about Shapiro time delay has any basis in fact since you haven't actually studied the phenomenon.

    In physics, people make predictions about physical phenomena (like in the case of the Shapiro paper). You are apparently making claims without any way to tie your claims to actual physical measurements. If you have no means of calculating a galaxy rotation curve, how do you claim that all physicists and astronomers are incorrect when they calculate the galaxy rotation curve?

    Can you please show us where all cosmologists go wrong when they calculate the gravitational effects of a homogeneous space? Since they have a lot of calculations based on this that match observations, they must be pretty lucky.
     
    krash661 likes this.
  8. Farsight Valued Senior Member

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    Yes. They use the ΛCDM model which uses the Friedmann–Lemaître–Robertson–Walker metric which "starts with the assumption of homogeneity and isotropy of space". That's a very bad assumption, because like Einstein said, a gravitational field is a place where space is neither homogeneous nor isotropic. They just don't understand general relativity, and they just can't find that pesky dark matter. Comical, isn't it?
     
  9. PhysBang Valued Senior Member

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    Can you show a single example of such a cosmological assumption being used to calculate galaxy rotation curves?

    You may be believing the lies that you tell others, but it is not the case that galaxy rotation curves require that one commit to a particular cosmology in order to do the calculation.

    So you now have the burden of the following:
    1. Show how the assumption of the FLRW metric changes the prediction of a galaxy rotation curve.
    2. Produce an example of a scientist using the assumption of the FLRW metric in order to calculate a galaxy rotation curve (from a legitimate source used to derive the presence of anomalous non-luminous mass within a galaxy).
    3. Produce the correct way to predict a galxy rotation curve using your understanding of general relativity.

    Note that these questions have been asked of you before! You dodged them then. Please either withdraw your wild claims, answer the questions, or continue to show people your deceptive character.
     
  10. Farsight Valued Senior Member

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    Are you for real? It's the ΛCDM model which uses the Friedmann–Lemaître–Robertson–Walker metric which "starts with the assumption of homogeneity and isotropy of space". And they can't find the dark matter. And they haven't thought for a moment about the raisin-cake analogy wherein space expands between the galaxies but not within. Space has expanded a thousandfold since the CMBR. That's a lot of inhomogeneous space around each and every galaxy like a halo. And guess what: inhomogeneous space is what a gravitational field is!

    I don't tell any lies. You do. Au contraire, I'm demonstrably honest and civil. Everybody can read my posts. And yours.

    See above.

    No.

    No. Anyway, just do it the same way as you do it now, but appreciate that space has its vacuum energy which has a mass equivalence and a gravitational effect. Appreciate that Einstein described space as a thing, not nothing, and that space is dark and there's a lot of it about.

    Get lost you dishonest ad-hominem troll.
     
    Last edited: Dec 30, 2014
  11. paddoboy Valued Senior Member

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    21,647

    I have often seen you being demonstrably dishonest and uncivil many times....
    And ignorant of what cosmology is all about to boot.
    For example. Nothing is ever seen to be stopped at and near the EH of a BH.
    From any external frame, time just continually slows and light is redshifted beyond viewable range.
    From the local frame of someone falling into the BH, he proceeds as per normal...no time dilation, no red shifting, no nothing. [other then possible gravitational tidal effects]
     
  12. paddoboy Valued Senior Member

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    21,647
    Einstein also viewed space, time, and spacetime as one and the same.
    "The views of space and time which I wish to lay before you have sprung from the soil of experimental physics, and therein lies their strength. They are radical. Henceforth space by itself, and time by itself, are doomed to fade away into mere shadows, and only a kind of union of the two will preserve an independent reality"
    Hermann Minkowski
     
  13. paddoboy Valued Senior Member

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    Also Farsight what you urgently need to accept, especially since you are incessantly quoting the great man, is that Einstein was also a humble man, never backwards in admitting his blunders and at times, his faulty thinking.
    He also I'm sure, if alive today, would be quite appreciate and agreeable with the advancements and varifications of SR/GR made possible by state of the art equipment, and the valid interpretations now accepted today, with regards to cosmology.
     
  14. PhysBang Valued Senior Member

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    2,422
    Yes, I am for real, in that I have actually read the relevant papers and you are merely lying about your expertise. You are obviously lying here, since searching for dark matter in galaxy rotation curves is not a cosmological exercise, it is an astrophysical exercise.

    Again, if you can find a source that operates as you claim, then you support your case that you are a "physics expert". However, your behavior continues to support the claim that you are a "physics fraud".

    Yes, they can. And they will note that you continue to not answer my questions.

    So, again, you show that you are a liar because you again refuse to answer my question. What is the mistake in calculation that is being done? Where, specifically, are actual scientists making this mistake that you claim they are making.
    So, again, you show that you are a liar because you continue to refuse to answer direct questions. You are making claims about what scientists do without any evidence. You might as well claim that scientists assume the existence of unicorns when calculating galaxy rotation curves.

    This is a lie. You have claimed that there is an error that all physicists and astronomers have done and that this error means that there is no need for dark matter. Let's see your evidence.

    How can I be dishonest for pointing out that you refuse to answer questions when you proceed to refuse to answer questions. Literally, one of your responses was simply, "No." Now you are merely insulting me rather than answering direct questions.

    Let's list the questions you avoided again:
    1. Show how the assumption of the FLRW metric changes the prediction of a galaxy rotation curve.
    2. Produce an example of a scientist using the assumption of the FLRW metric in order to calculate a galaxy rotation curve (from a legitimate source used to derive the presence of anomalous non-luminous mass within a galaxy).
    3. Produce the correct way to predict a galxy rotation curve using your understanding of general relativity.
     
  15. danshawen Valued Senior Member

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    It certainly does, OnlyMe! I was wrong and you (and a few others here) were right, which is a big relief.

    Once the problem had been reduced to one I had solved before, the answer was obvious, because it was the same problem as understanding how photons trapped between a pair of mirrors on a moving spaceship means that different inertial reference frames measure exactly the same value for c, no matter what path the light beam takes between the mirrors.

    And thus ends the saga of the 30 year unsolved relativity paradox that had been bugging me. With all of your help and encouragement, the issue was resolved, and so physical reality now actually makes sense to me again, literally.

    Farsight: you helped, too, by changing the pulses back into billiard balls. I think a similar problem framed with those inspired me to devise this one myself a very long time ago. Exactly the same analysis works as well for matter as it does for energy, the only differences being that Doppler shifts replace Lorentz distortion, and there can be no actual 'observers' who observe anything while traveling at a speed of c. As rpenner observed, some of us had gotten short changed in our relativity education. And I'm also certain that I was not the only one.

    I was hoping that something about this particular thought experiment with energy pulses might actually reveal a deeper relationship between energy and the dimension we call time, but alas, there is really nothing new contained in its solution that any freshman physics student of relativity shouldn't be able to handle. The various fields associated with energy pulses oscillate at regular intervals suggesting that time itself is of a much finer grain than a wavelength, even a blue Doppler shifted one. And space that appears to stretch, contorting angles, lengths, and time is nothing that is very new either. None of these effects appear to contort physical reality in a manner that is not consistent with the ideas of relativity.
     
  16. danshawen Valued Senior Member

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    3,942
    I haven't seen the term "phase velocity" myself in many moons. It used to have a meaning as opposed to "group velocity". The legend was that phase velocity could be faster than light in a vacuum, whereas group velocity could not exceed it. At least, that's how they taught it to select engineers who explained it to me.

    Very impressive posts throughout this thread, krash661! Thanks.
     
  17. Farsight Valued Senior Member

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    3,475
    My pleasure.

    Yes. Take a look at gravitational time dilation on Wiki and note the bit that says electromagnetic radiation and matter may be equally affected, since they are made of the same essence. Think pair production and electron diffraction and spinors and the wave nature of matter and annihilation , then think of an electron as light going round and round, and you won't go far wrong.

    The more I learn about physics, the more I realise that there are issues in contemporary teaching.

    You know Dan, you seem to have a problem in seeing how simple things are. Find a clock and open it up. Ask yourself what a clock does. It doesn't literally "measure the flow of time". There's no time flowing through a clock like gas through a gas meter. The clock features a pendulum or a cogs and rockers or a vibrating crystal, and it displays a cumulative measure of local motion. Have a read of the OP in Time Travel is Science Fiction. Unfortunately a vindictive "moderator" moved the thread to alternative theories and locked it.

    No you haven't. So that's enough from you.
     
  18. PhysBang Valued Senior Member

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    That part of the wiki is clearly an addition from a crank, since it also leads to a supporting link that has nothing to do with a claim. You have a knack for ignoring the science and picking out the crazy.
    So far, you have learned almost nothing, as you demonstrate over and over again. Please learn some physics.
     
  19. krash661 [MK6] transitioning scifi to reality Valued Senior Member

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    is this part of your civility ?
     
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  20. PhysBang Valued Senior Member

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    2,422
    Indeed, more examples of Farsight offering abuse when he cannot offer evidence. Farsight alternately knows, then doesn't know, that his opinions on physics are alternative to mainstream interpretations. So he insults mainstream physicists when they disagree with him, and insults moderators for identifying his opinions as alternative to mainstream.
     
  21. danshawen Valued Senior Member

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    3,942
    Thanks for self-identifying, Farsight.

    FYI, I haven't written or published anything like a book, but if I did, this:

    http://www.amazon.com/RELATIVITY-Theory-Everything-John-Duffield/dp/0956097804#customerReviews

    and in particular the negative customer reviews (which are all that is visible) about this book on Amazon would make me consider asking the publisher to recall all of the available copies and appropriately dispose of them.

    Not to worry, Farsight. If it were up to me (and on Amazon reviews, it actually is!) some more notable works that are supposedly not fictional, but cutting edge physics sometimes get panned by me as even worse. My interest in reading what you wrote is piqued, and I don't even care if your strength is in computer science, but $63 is a bit much to ask. Billy T's 'Dark Visitor' (not the current title) evidently sold for less, but that one is just fiction anyway.

    Arrgh! you actually included the word 'geometry' in it's title. Euclidean mapped space really doesn't behave anything like the predictions of relativity. We have just discussed this. Minkowski's take on space-time geometry certainly works, up to a point, but some crucial element is missing. I can't quite decide what that is, but one critical problem is that he describes continuous time and space as though it were discrete. It's only discrete when energy becomes bound.

    Ah! a list of references at the end of the book appears in the preview. That's good.

    I can't even stomach reading anything by Brian Greene, for instance. I tried really hard last time, but you know what? If you can't actually observe multiverse or block universe stuff from this universe, I don't want to even hear, much less read anything about it. Sean Carroll's 'Particle at the End of the Universe' was very good. His other stuff, not so much.

    The same goes for any long nose hair yarns about the Big Bang. The math we would need to get a handle on predicting anything like what actually happened is literally all smoke and mirrors. Some of it is so bad, it shouldn't even be a part of any state's Common Core science curriculum. Unfortunately, it is. I did complain to one of the authors of the CC science curriculum for our state. Like John Dewey, they seem intent on teaching a consensus view of science, even in fields where the dust has not even begun to settle. It is a practical approach to education, but I for one don't like it.

    While I was going to school at the UofMD in the 1970's, our Thermodynamics professor handed out copies of Jearl Walker's 'Flying Circus of Physics' early manuscript to all of his physics students. Even the manuscript was solid gold. I will treasure it forever.

    Going out dancing with my wife tonight for New Years. Happy New Year, all.
     
    Last edited: Jan 1, 2015
  22. Farsight Valued Senior Member

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    3,475
    Those negative reviews are vindictive, not honest, and it's essentially self-published, and no longer officially on sale. Amazon however are a law unto themselves and are selling some secondhand copies at collectors-item prices. The cover price is £9.99. And there is a "look inside" feature, but I'm not sure it's available if you haven't bought from Amazon.co.uk.

    You betchya. A gravitational field is curved spacetime, but that isn't curved space. It's inhomogeneous space. The electromagnetic field is curved space.

    Minkowski's problem is that he died. He didn't have time to appreciate that what we're really dealing with is space and motion rather than space and time.

    I ended up with a whole cupboard full of papers, many of which you've never heard of. But they're good stuff.

    Me too. I'm afraid there's a lot of people out there peddling woo.

    I kind of like Sean Carroll. He's droll, I reckon he'd be good company in a bar. But I'm a bit concerned that he's going all loopy-multiverse on us, and turning from a bit of a quack into a total crackpot. The trouble is that he doesn't listen to the comments on his blog, he talks at people, not too them. I fear it will end badly.

    Honest injun, when you understand relativity like I do, you know space just has to expand. It can't not expand. And it can't be infinite. There has to be some kind of big bang. But not inflation.

    Nor I. I don't think it's practical, I think it's dangerous. And all too often if you challenge what quack is teaching, he will accuse you of poisoning young minds, when in truth he wants the monopoly on that.

    Happy New year. Now I have to vacuum the carpets, because we have a "do" tomorrow.
     
  23. quantum_wave Contemplating the "as yet" unknown Valued Senior Member

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    As an obscure layman science enthusiast who is focused on cosmology, I greatly appreciate both of you. I see you both as seekers of the truth, and I trust you for that and like you for being that way. Sometimes you both seem to imply that you have found the truth, and I don't trust that, but I believe you are like me in that respect. You both know of my hobby-model, and it is nothing more that my evolving understanding. It changes as my understanding improves, and unless I'm wrong, you would both agree that your views change over time as you put more of it together for yourselves.

    I spent New Years Eve home with a cold and cough; its going around. Good luck with your personal searches, and have a truly happy year!
     
    Last edited: Jan 1, 2015

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