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Time dilation and the big bang

  1. Jan 12, 2004 #1
    I'm new to this forum and need to throw out a question:

    I'd like to know what the difference in the time that I might record if I were standing at the beginning of the Big Bang looking forward and if I were here now looking back.

    In other words how old would the universe look if I were God sitting at the beginning?

    This is inspired by the book "Big Bang and Genesis" by Gerald Schroeder.

    Someone told me his math was wrong, but I don't know the math so hopefully someone can explain it.

    Here are some relationships he gives that may be wrong:

    Day 1: 24 hrs = 8billion yrs = CBR blueshift from beginning (z+1) is 1

    Day 2: 24hrs = 4billion yrs = (z+1) is 2x10^12

    Day 3: 24hrs = 2billion yrs = (z+1) is 3x10^12

    Day 4: 24hrs = 1billion yrs = (z+1) is 3.5x10^12

    Day 5: 24hrs = 0.5billion yrs = (z+1) is 3.7x10^12

    Day 6: 24hrs = 0.25billion yrs = (z+1) is 3.9x10^12

    Someone pointed out that he should have used base e, not 2, and that the epochs of billions of years would actually increase in length gradually according to the CBR redshift/blueshift.

    Can you help???
  2. jcsd
  3. Jan 13, 2004 #2
    Personally, my opinion on this is that he took the number 16 billion, and attempted to figure out how to create a pattern to split it into seven days, so as to have approximately 16 billion years taken up, and each passing day have it split in half...It seems that he has been able to do this by the points you have put down there:

    Day seven would become:

    Day 7: 24hrs = 0.125billion yrs = (z+1) is 3.9-4.0x10^12

    If he wanted, we could somehow create a limit out of this that makes such as Day 8 would turn into 0.0625billion years.

    The lim as x->16, then you would somehow have to corollate that to the scale of days to yrs with the blueshift method.

    Since I am in school right now, i don't have enough time to figure out an exact limit for you, but I will try it out whenever I get home, unless someone else wishes to do it for me/you. Then by using his method, we can see how all he was doing was making it run as close as possible to 16 billion yrs, without ever touching it.
    -Bob Smith
  4. Jan 13, 2004 #3
    yea, i thought he was just trying to figure a way to reconcile cosmology and genesis, even if it's artificial.

    I mean, can anyone arbitrarily pick a power law that will spell out any old relationship between our reference frame and another?

    I hope not.
  5. Jan 13, 2004 #4


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    Hello shrumeo and hello Bob Scionpunk,

    whatever else you read it is a good idea to also
    read the mainstream consensus view of cosmology
    and the best up-to-date short paper I know of is
    http://arxiv.org/astro-ph/0305179 [Broken]

    There's also Ned Wright Cosmology Tutorial, Eric Linder, Michael Turner, Wendy Freedman, and a bunch of others but recent (2003) mainstream academic cosmologists are basically in agreement for the moment.

    The answer to your question (from a mainstream consensus viewpoint, which, remember, may be proven wrong!) is that there IS a preferred
    frame in cosmology
    there is an idea of an observer being at rest---stationary with respect to the CMB and to the expansionprocess going on (called "the Hubble flow" in jargon language.)
    These stationary observers are also called "comoving" with the Hubble flow, or "comoving" with the expansion of the universe.

    Stationary observers can agree on time (approximately at least) and simultaneity of events and the age of the universe.

    The current estimate is not 16 billion but around 13.8 billion, call it 14.

    The point is that all stationary observers can agree at the present moment the age is 14 (or whatever)

    Someone who lived, say, back at 1 billion from BB and watched matter begin to condense into galaxies might have watched the Milkyway begin to nucleate and stars begin to form and might have PREDICTED that in 13 more billion years there would be a spiral galaxy with us in it. And that person would (if he also was at rest with respect to the CMB) be using an idea of time roughly commensurate with ours.

    So if he predicted "at 14 billion from the beginning, in this galaxy I see forming here which I will tentatively call Milky, there will exist a restless shifty-eyed being named Bob Smith"
    then that prediction would be using essentially the same time parameter as we do.

    Not perfectly exactly the same, because gravity effects the rate time passes, but good enough for government work.

    the fact that cosmology has a preferred frame, at least approximately, and likewise an idea of being at rest and a notion of simultaneity sometimes confuses and disturbs
    people, because the the 1905 peanuts version of relativity called "special" relativity does NOT have these things. ( 1905 "special" does not have a preferred frame and does not have a useful notion of simultaneity or being at rest) Einstein's real contribution (in his own estimation) was not the 1905 theory but instead 1915 general relativity----which is the basis of cosmology and different.

    The space of 1905 "special" does not even expand!!!
    So you have to take it with a grain of salt
    its complicated and I couldnt give you the whole picture
    so Im just rocking the boat a little

    that idea of someone in the past looking forwards and imagining us looking back at him, is....I dont know...strange, eery almost.
    Last edited by a moderator: May 1, 2017
  6. Jan 13, 2004 #5
    I like the argument, and all of the information that you used to support you. It is alot to take in, and I definitely enjoyed reading it. Helps me learn more about our universe.

    The only reason I had said 16 billion, was because i was refering to all of the years added up:8billion yrs+4billion yrs+2billion yrs+1billion yrs+.5billion yrs+.25billion yrs. It adds up to about 15.75 billion years total, then of course i added in the .125, which made it 15.875 years.

    Just out of curiosity, do you think you could explain to me how gravity effects the rate time passes? I have always wondered about this, but never thought of asking about it until i read your response.
    -Bob Smith
  7. Jan 13, 2004 #6
    Have you noticed that the ancient patriarchs in Geneses lived longer the longer back in time we go in the Bible?

    I made a list of them and their ages one time, and as the Bible progresses forward in the Old Testament, the ages the old men lived gradually became shorter and shorter over the centuries.

    Also, notice in Genesis 1, the life-form creation sequence matches the fossil record and there is even a long gap between the creation of plants and animal life.
  8. Jan 13, 2004 #7
    I am not to sure about this part...I mean, it was only days...not any significant time period...more like hours actually...and where does it give the list of creatures in order from first created to last created? I am not seeing this as some people may be seeing it...
    -Bob Smith
  9. Jan 13, 2004 #8
    It’s very fundamental. No details. Just an outline. Days = “eras” or “epochs”.

    Sequence of events:

    1) earth with no life, 2) plant life, 3) gap of one era (one “day”), 4) animal life in sea; 5) birds, 6) land mammals, 7) humans. This matches the fossil record.

    Today in biology and paleontology, this is known as the “punctuated equilibrium” theory of sudden appearances of new life forms.
  10. Jan 14, 2004 #9


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    Thankyou for asking, Bob.

    I can repeat for you the FORMULA according to which gravity effects the rate of time passage
    but I can not explain to you the mechanism by which clocks run faster at the top of a high building and slower down at street level.

    The dependence on altitude of the rate that time passes is an observed fact and the GPS would not work unless it was constantly taking into account the altitude of each satellite and adjusting for this effect. Each GPS satellite has a highly accurate clock in it and is sending a timesignal to the locator units on the ground. Because of their higher altitude the seconds and hours pass quicker for the clocks up in the satellites. It must be allowed for. Time is different at the top of a mountain. This is just an empirical fact and I can tell you the formula the GPS system uses to allow for it.
    But that is not the same as explaining the mechanism of it.

    Let M be the mass of the earth and R be the distance from center.
    Let c be the speed of light and G be Newton's gravity constant.

    Compared with time told by a clock far enough from earth so its effect can be neglected, time at distance R from earth center goes SLOWER by a certain factor and that factor is

    [tex]\frac{1}{\sqrt{1 - 2GM/c^2R}}[/tex]

    In the case of the earth [tex]2GM/c^2[/tex]is about 1 centimeter.

    Therefore [tex]2GM/c^2R[/tex] is about equal to

    [tex]\frac{1 centimeter}{clocks distance from earth center}[/tex]

    For a clock at the earth's surface that is obviously a small number, close to zero. One minus that number is close to one.
    The square root is even closer to one.
    One over the square root is just a tad bigger than one.
    Last edited: Jan 14, 2004
  11. Jan 14, 2004 #10
    Re: Re: time dilation

    I have my thoughts about that. I tend to disagree with that assumption. I think that the term "year" meant something else back then. Consider a more detailed look at the Bible in this respect. Those people who were supposed to have lived so long didn't have children until they were old. Why? Perhaps some had problems but surely not all of them since when they have that list of so-n-so begat so-n-so etc all of them had children at what we'd call "old" (I forget the actual numbers). Surely men didn't waite until they were old to have sex? Sounds fishy to me.
  12. Jan 14, 2004 #11
    My personal opinion to this is that i agree with you. The sexual drive of a human male is at it's top performance at the age of 19. This basically means...without protection back then...they should have been having sex, and babies for a long period of time...meaning more babies, meaning more humans...I tend to disagree with the thought that they wouldn't have had their babies at the ages of seven hundred and such...even them calling months, years, would still be stretching it a little. I mean, how is it that a man an save himself up all the way until he is seven hundred years old, and not have sex with a woman so as to create babies and such. Certainly without protection you would see the entire thing blowing out of proportion, and them having over two hundred little children, which that can't happen...how would they be able to raise them all?

    I tend to see the equation correctly...but could you give me an example maybe of how the equation works? I mean...i am sort of understanding the basics...but what i would like to know is how it operates in the real world....it is very confusing seeing an equation and not knowing how to make it work...
  13. Jan 14, 2004 #12


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    Tell me about it!
    I know how frustrating it is to have an equation that works (fits realworld experience like the GPS locator system etc)
    and yet not know of a MECHANISM behind it.

    I told you that I could not supply a mechanism, only the formula.

    We are just humans. We dont know everything. what can I say?

    There should be some kind of picture of a mechanism where
    gravity reaches out with little hooks and slows down the
    cogwheels of the ticking clock so that it runs slower.

    But dammitall I dont know of any such mechanistic picture.

    Einstein produced arguments for why it has to be like that,
    but that is still no satisfactory mechanism.

    Maybe some other PF poster can explain in a way that will satisfy you Bob Smith and quench your burning thirst for knowledge but I will take my leave from this thread, wishing you all the best.

    Waite is an interesting name. In past centuries in England, Waites
    were children that went around singing Christmas Carols. It was considered proper to feed them something or give them presents when they came around to sing at your door. In his prophetic song called "Future" the musical poet Leonard Cohen says something vaguely like love is the only insurance against total mayhem and disaster.
    Let us be charitable to one another and not talk too much sillystuff.
  14. Jan 14, 2004 #13


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    Regarding Gravitational Time Dilation

    Don't know if this will help, but I'm gonna throw it out there anyways.

    You are familliar, perhaps, with those diagrams of how gravity works. You know, the ones that show space being curved by a massive object like this? Well, you might notice that wherever space gets curved, it gets stretched as well. You've probably also heard that space and time are intimately linked, or even that they are, at some basic level, one and the same thing; "spacetime".

    Just combine those two ideas, that gravity stretches space and that space is time, and you get the revelation that gravity stretches time. So the distance from one second to the next is greater within a gravity well than outside it where spacetime is flatter.
  15. Jan 16, 2004 #14


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    mentor note...
    Arcon, DW - your sidebar argument has been deleted from this topic. Please stop hijacking topics with it.

    ok, my turn to hijack...
    (1) The fossil record shows that land mammals came before birds...by like something on the order of 30 million years.
    (2) That is not punctuated equilibrium. P.E. describes how the rate of evolution often is marked by long periods of statis punctuated by relatively shorter periods (geologically speaking) of rapid change.
  16. Jan 16, 2004 #15


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    It is amazing to me how so many people will try so hard to force fit biblical fables to the facts. It is true that you could find a frame according to which a person on Earth lives for hundereds of that frame's years and one could find a frame according to which the earth has only existed a matter of that frame's days, but even so the sequence of the genisis account is way wrong. And rather than those who wrote what they professed to be the the word of God(s) speaking in riddles of time travel and time dilation, it is obvious to anyone with an open mind that these were mere fables and that even the majority of the "self" inconsistencies in the stories are explained by the word of mouth grapevine effect prior to their being written down.
  17. Jan 16, 2004 #16
    i know i know

    i think Schroeder was just trying to pacify the real hard core bible bangers who want to challenge current cosmological theory

    i don't know if enough of them read the book to deflate any of the Creation "Science" or Intellegent Design folk's will to impede the progress of knowledge
  18. Jan 16, 2004 #17


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    You think so? Seems to me more like he was trying to change the interpretation of the Bible to fit the theory than vise versa. At any rate, I hope nobody minds if I try hijacking this thread to talk about "time dilation"!

    I was wondering about frame dragging. If frame dragging proves real (and I think this likely), will time be slower in one direction and faster in the opposite direction around a rotating gravity source? I tend to think it must be, since space is being dragged and space is time. What do the rest fo you think, and do any of you know of any theoreticall work on this question?
  19. Jan 16, 2004 #18
    Why would you think that space is time? That certainly isn't true. And it sure isn't something Einstein held to be true.
  20. Jan 18, 2004 #19
    So the “dinosaurs” were early “birds” theory is now out? I wish you guys would make up your mind.
  21. Jan 18, 2004 #20
    Is the Piltdown Man still “out” or is he back “in” again? Is the Catastrophism theory still “in” or is it “out” again? What about Galtonian eugenics? Is that “out” or “in” now? What about Darwin’s claim that women are less intelligent than men? Is that “out” or “in”?

    What about Pangaea? Since that term appears in many of the old Greek New Testament versions as “pan ge” or something similar, meaning the dry land above the waters, is the Pangaea term “out” or “in” today? You need to keep us all informed as to what the latest “politically correct” science concepts are today, since they tend to change so often, and I want to know what I’m officially supposed to believe in science theory.
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