Seeking Evidence of Cosmological Inflation:

Discussion in 'Astronomy, Exobiology, & Cosmology' started by paddoboy, Apr 26, 2016.

  1. Write4U Valued Senior Member

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    Thanks for the link, I shall watch it.
     
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  3. Xelasnave.1947 Valued Senior Member

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    Thank you for going over that.

    I think I now understand what you are considering.
    Upon my understanding of mainstream cosmology, which I point out is minimal, all we can say is the Universe is all there is and so we do not expand into "nothingness" as you suggest.

    It may be the way you suggest but that is not what mainstream cosmology has covered in the Big Bang Theory.

    Lets take your idea as a hypothisis, even if we start with nothing more than we all think the idea sounds pretty darn good. To take it further we need some observation or even an extention of some existing math which can offer some support.

    It would seem that within the current Big Bang Theory we have no support at all because put very simply there is no outside hence by extention no outside nothingness.
    The idea sounds as good as many others but I think it has little prospect of growing up to become a theory.

    The other problem is simply if there be an edge of the Universe where it meets "nothingness" I suggest as there is nothing there it is inescapable that there must be something, so what could that be? I dont know and have no idea how we could make an observation.

    I have spent years considering nothing and conclude it is nonexistent.

    Think about what I have said about nothing. My conclusion is that nothing is perhaps the closest we can come as opposite to infinite. If nothing exists between two bodies it means they will be as close as possible to each other for if there is any gap between them it will indeed be something.

    So lets climb back inside our Universe and consider what is causing expansion using only mechanisms that are within the Universe.

    Now we can say we do not have an answer at this point.

    The implication is energy is required so we ask what is this energy. We answer mmmm we dont know what it is but it must be there.

    We are in the dark... Mmmm while we continue to work on the problem we shall call this mysterious energy Dark Energy so folk know the term is a place holder.

    And I add I dont have the answers nor am I defending cosmology but our current model is where we are at the moment.

    Alex
     
    Last edited: May 3, 2016
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  5. Xelasnave.1947 Valued Senior Member

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  7. Schmelzer Valued Senior Member

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    An excuse for ignoring arguments. And, of course, a rather cheap one, given that you have not a single argument (your prejudice is none) against my ether theories.
    Yes, but what you expect if somebody tries to sell factually false statements by adding a "that in simple language means". (Some completely confused nonsense disposed)
    So , we see:
    [1] A repetition of a triviality which nobody has questioned.
    [2] A wrong statement, shown to be wrong, preceded by "that in simple language means". No. It doesn't mean. And using simple language is not a justification for making wrong statements.

    And to claim that "most professionals put it" is a lie too. Feel free to quote some professional. I mean quote. And I mean professionals, not journalists. I do not mean interpret in your fantasy some version of the triviality [1] as meaning this. But I mean quote your particular wrong sentence "spacetime can expand at FTL". Ok? I do not think it is impossible, I would suggest to search among string theorists (scnr). But these are certainly not "most".
     
  8. Write4U Valued Senior Member

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    Thank you (and Paddo) for taking the time to consider my tentative proposition.

    It was intended as probative, to see if there is any reliable information available. I have not had time yet to see the Krauss clip, so I better start with that. At least it will give me an idea of current thinking by *knowledgeable fellows*, before even attempting to discuss the subject.

    To admin. Thanks for allowing me the freedom to present such speculative thoughts.
    It is what makes SciForums my favorite science forum.
     
  9. Write4U Valued Senior Member

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  10. paddoboy Valued Senior Member

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    No just fact, sorry about that.
    I'm selling nothing other than your rather pedantic prima donna approach to this subject and your refusal to accept that what I claim is fact.
    No, both can be said to be correct despite your squirming and denigration of simple language...again a prima donna approach.

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    I'm not claiming anything is wrong: You are doing the claiming and other than Professor Carroll, no one appears to accept your rather rigid "no room to move" stance, and the obvious reason why you chose to take it.
    And I'm certainly not going to waste my time to "quote" the professionals that also say exactly what I have........Other than of course from the professional that does agree with your take on the situation and hard line stance, and who you claim as a supporter...the respectable and reputable Professor Carroll.
    But perhaps your attitude and prima donna stance has prevented you from reading his link, which by the way I supplied.
    He mentions the other professionals himself, so you go call him a liar my friend, in another rather less than professional emotional outburst
    here........
    http://www.preposterousuniverse.com...never-expands-faster-than-the-speed-of-light/
    "Experts get this one wrong all the time. “Inflation was a period of superluminal expansion” is repeated, for example, in these texts by by Tai-Peng Cheng, by Joel Primack, and by Lawrence Krauss, all of whom should certainly know better".
    end of quote! [just in case you want to highlight your unprofessionalism again and accuse me of plaegerism]
    So there you are, from your own supporter, and again despite your "liar" nonsense, there have been plenty more...just as Professor Krauss even admits to.

    Now Schmelzer I realise that your "professional" nature will dictate that you try and squirm around what I have said and supported by Carroll, and I have seen you in action in the political forum and how you refuse to accept logic and reasonability in those threads, so that's it for me with regards to yourself and this question at hand.
    We are now probably starting to annoy other reasonable members, so I'll leave the last unprofessional rant to yourself.

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    Go for it!

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    My claim stands none the less that the following can both be seen as correct and further more, both used by other professionals
    ,[1]Take two objects far enough apart, and the recessional velocity, due to spacetime expansion will be in excess of "c"
    [2] That in simple language means just as most professionals put it, that spacetime can expand at FTL.
     
  11. paddoboy Valued Senior Member

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    Correction of an error on my part: The Professor highlighted "red"should be Professor Carroll.
     
  12. Schmelzer Valued Senior Member

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    Fine. Why should I accuse you of unprofessionalism if you follow professional rules? Correct quotation, and you have even a quote similar to what I have requested. More of this and I will have to stop my "uneducable". It remains the minor quibble that this does not prove that "as most professionals put it". But, of course, you have no way to organize a poll to support this. But wait:
    No need to call him a liar. What I have named a lie is your "most", and this remains your own invention. And, no, just to clarify, even if he would have said "most", I would have named this an exaggeration only. Because there would have been no interest in falsifying this issue - all he needs to make his point are some examples.

    Not nice. I will do this for you. Here is your beloved Krauss, from https://physics.aps.org/articles/v7/64
    This is indeed simply wrong. For the reasons explained. But, maybe this was simply an example of sloppy speaking. Here is the quote from Cheng, and it is not that bad:
    Here he has used the "superluminal expansion", but here it is clear that this is simply sloppy speech, because he has added a formula ($\dot{a}R_0 > c$) to explain what he means. And, quite typical for the use of sloppy speech by scientists, this formula is fine, it makes sense. Here the expansion rate $\dot{a}(t)$ (unit 1/s) is multiplied by a radius $R_0$ (looks like the curvature radius of the universe or so) which gives, indeed, a velocity (unit m/s) which one compare with c.

    Primack is some short, two page summary of inflation in an article about something different, namely dark matter and structure formation. Reading this summary, one can conclude that he has not a very high opinion about inflation theory. This may explain inaccuracies.

    And, then, again:
    Which "no room to move"??????????? So, again, I have to ask you: If you make a claim about what I think, then quote me. I mean quote me about this.
    That spacetime can expand as FTL is nonsense. Nonsense in simple language is nonsense too. That some professionals sometimes write nonsense is an unfortunate fact. That most do this is Paddoboy's invention. As least up to now we have only three explicit examples of professionals who have made this claim, one of them in sloppy speech (explaining in a formula what was meant), and no poll.
     
  13. paddoboy Valued Senior Member

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    Ignoring our unprofessional Mr "I don't care" and his pedant

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    As I have said many times, there is nothing wrong in speculation......As long as one accepts it as speculative.
    Did you read the speculative scenario of the universe from nothing I also linked to?
    The hard part with cosmology and cosmological theories, is that a lot of them seem to be counter intuitive.eg: Time dilation and length contraction, yet we have the observational and experimental evidence of both.
    Hubble measured the cosmological redshifts of distant galaxies and Einstein being the great and humble man he is, exclaimed he had made the biggest blunder in his life: From the observational evidence of a expanding universe, we deduced the BB....Since that deduction, other evidence such as the CMBR at 2.7K has re-enforced the BB so that it is now mostly accepted.
    The further we look into the universe, the faster it appears to be expanding, so much so, that the most distant galaxies are expanding at FTL, due to spacetime expansion......
    In my opinion, the greatest bit of evidence to support current cosmological picture is how our most important theories such as SR, GR the BB and how from the simplest most fundamental particles such as quarks and electrons, we can reasonably logically arrive at the universe we see today: In effect, they all fit together snugly like a hand in a glove.
    That says a lot about the validity of what we see.
    The why's though, as you seem to be asking is another question/s

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    Why does gravity manifest itself when spacetime is curved in the presence of mass?
    Why is the speed of light what it is?
    Is the universe infinite or just immeasurably big?
    [Personally the part I always have difficulty wrapping my head around....how could anything be infinite....mind you, I'm not doubting that possibility, just my limited scope in understanding it.

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    ]
    Great questions! But as yet not entirely answerable.
     
  14. Xelasnave.1947 Valued Senior Member

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    It is a wise man who can imagine a rod with out ends.

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    Alex
     
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  15. Schmelzer Valued Senior Member

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    A purely rhetorical move. Because even if you would produce such papers, Paddoboy would completely ignore the content.

    The content of the Hamilton rebuttal at http://ilja-schmelzer.de/papers/river.pdf you have ignored. Despite the fact that Hamilton himself has given a quite positive review, see http://ilja-schmelzer.de/papers/river.php
    where he wrote
    And the content of my published papers you also ignore completely, and restrict yourself to the observation that they are yet ignored by the mainstream.
     
  16. paddoboy Valued Senior Member

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    No, I ignore no content, but I do reject the fabricated nonsense by cranks, anti mainstream frauds and the alternative brigade, and lay people with a bee in their bonnet, as generally agenda inspired. [the god and Schmezer...nice double!

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    ]
    And again thanks for the nice adhom, which of course you will deny with some unreal semantic nonsense you have become well known for

    Firstly at your site [

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    ] you say "WE" WHO IS WE?
    "We have criticized a proposal by Hamilton and Lisle"

    Secondly you quote Professor Hamilton a saying, " I accept those criticisms; that is to say, I agree that our "river model" for black holes does not generalize to all possible spacetimes in GR, and in that sense is not fundamental"but ignore the rest of the reply thus,
    " However, I think that our "river model" remains the best way to teach a valid conceptual picture of black holes that students and the general public can understand. It is certainly much better than the "rubber-sheet" analogy. In my view, the most important thing to understand about black holes is the horizon (next being the singularity). Our "river model" does a great job with respect to these priorities. As this paper puts it, "these theories allow the students to develop reasonable intuitions about what happens. This is possibly even more important than teaching the mathematics of these theories itself."

    Thirdly and most importantly, it still remains that your ether paper languishing in oblivion, unnoticed and ignored.....at least the last time I looked quite a while ago.
    Professor Hamilton's paper is cited, many times.

    PS: Schmelzer, Not sure if you realise what an analogy is, but all that do not have an agenda in this debate do realise that the river/waterfall model is just that....an analogy, and just as I had to tell your Ally the god earlier in the piece.
     
    Last edited: May 4, 2016
  17. paddoboy Valued Senior Member

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    A reply from Professor Hamilton via E-Mail that I requested......


    Barry,

    Curiously enough, it was precisely this issue that first brought my
    attention to the river model. Jason Lisle, at that time a brand new
    graduate student of astrophysics at the University of Colorado, Boulder,
    came to my office to explain that he had written a little program that
    pretended that a Schwarzschild black hole was a river of space falling
    in at the Newtonian escape velocity. He found that the program yielded
    the correct radial positions of the horizon and the photon sphere. At
    that time I dismissed his idea, since surely I would have heard such a
    simple thing before. Some while later, while teaching graduate general
    relativity, I revisited Jason's idea, and realized that he was right.
    Later, a professor at Columbia pointed out to me that the metric behind
    the idea was discovered by Allvar Gullstrand, and independently by Paul
    Painleve, both in 1921.

    In the river model, to follow the trajectory of a particle, as you step
    from one time to the next, you have to Lorentz boost the particle
    4-velocity by the change in the river velocity from one point to the next.

    Andrew
     
  18. paddoboy Valued Senior Member

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    double post
     
  19. Schmelzer Valued Senior Member

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    This is a style used in many scientific papers. Classical old German style, I think. In modern american style one can find the "I" more often. The meaning is "the readers together with me".
    The point being? I have given the link with the full answer, and I see no reason for a full quote.
    What is the point of this remark? What indication do you have that I do not realize what an analogy is? Do you think analogies cannot be criticized, in particular for being misleading, by giving wrong associations?
     
  20. paddoboy Valued Senior Member

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    The readers together with me?
    As I predictably said, more semantical nonsense.
    The point being that as many agenda laden detractors often do, taking a sentence out of context.
    The analogy was not misleading, as the additional information I showed above, and you decided to ignore showed. Limited maybe as all analogies are.
     
  21. Schmelzer Valued Senior Member

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    Whatever, simply traditional German style.

    I have made a small check, looking at some accidental Einstein papers, http://einsteinpapers.press.princeton.edu/vol2-doc/114?ajax Remarkably, it shows an "ich" (I) on the first page - in a reference to a former Einstein paper. But, then, on the second page it continues with "wir". And in http://einsteinpapers.press.princeton.edu/vol2-trans/63?ajax also translated as "we" .

    Tradition does not have to make much sense.
    An "out of context" accusation is justified when in the context the quoted text obtains a different meaning. This is not the case. Of course, what is not quoted can be supposed to contain meaningful information too - else, the author would have better omitted it. So, that the context simply contains other information does not justify an "out of context" accusation.
    One point is that an "analogy", which works only for a small amount of solutions, is not a good analogy. (An alternative analogy, which works for a greater class of solutions, is preferable.) Is this some point you could agree with?

    Another point is that a "river"-analogy, where the "water" disappears into nothing , is worse than a "river"-analogy where the "water" is conserved. Would you agree with this? And I think one can say that a "river"-analogy where the "water" analogon is not conserved is misleading.
     
  22. Xelasnave.1947 Valued Senior Member

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    Hi Schmelzer would an ether river work for you. I would have thought an ether model would be very happy with such a flow notion.
    I am sincerely curious and not looking to make any point or present an arguement.
    Alex
     
  23. paddoboy Valued Senior Member

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    I'm not arguing anymore with your smart arse semantics and usual side stepping......The river/waterfall analogy has been cited many times and is held in good regard.
     

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