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New Estimates for Universe's Age

Makarand writes "In a study published recently in the journal Science, a team of researchers say that they are 95% sure the universe is between 11.2 billion and 20 billion years old according to this article on Space.com. The new calculations from cosmologists at Case Western Reserve University and Dartmouth College involved new information about old star clusters in our galaxy and a better understanding of how stars evolve." Which blows my theory that the Universe is predated by Zsa Zsa Gabor, but oh well.

34 of 281 comments (clear)

  1. new estimates?!! by ideonode · · Score: 3, Interesting

    Last year, data supplied by the Hubble Space Telescope led to an apparently refined estimate of 13 billion to 14 billion years

    So, last year, they had an estimate of 13-14 billion. This year, it's 11-20 billion. Yeah to scientific progress!

    1. Re:new estimates?!! by Citi+Tech · · Score: 3, Funny

      Only 11 to 20 billion years and I'm somewhere between 4 to 693,000 years old

    2. Re:new estimates?!! by whimdot · · Score: 4, Informative

      Religions will try to tell you on what day the earth was created. National newspapers will tell you the age of the universe, plus or minus a billion years. A scientist will give another scientist an estimate and a confidence level.

    3. Re:new estimates?!! by tconnors · · Score: 5, Informative

      So, last year, they had an estimate of 13-14 billion. This year, it's 11-20 billion. Yeah to scientific progress!

      Science is not exactly a reputable astrophysical journal. I would tend to go with the estimate of 13-14 billion years. See this ppaper - the figure of H0=73+/-2(r)+/-7(s) km s-1 Mpc-1 (hmm, /. does not allow sup tags) combined with standard cosmological models (omega m = 0.3, lambda = 0.7) implies an age of 13+/-2 Gyr. I tend to believe this one more. The errors quotes are probably 1 sigma errors (ie, 68 precent confidence - double the errors for 95%).

      However, I am possibly biased, the author is my supevisor :)

    4. Re:new estimates?!! by SEWilco · · Score: 3, Funny
      the universe is between 11.2 billion and 20 billion years old

      I have to take their word for it. I can't remember anything before 8 billion years ago. Maybe my memory isn't what it used to be a couple of billion years ago.

    5. Re:new estimates?!! by CraigParticle · · Score: 5, Informative
      No, it's how the error estimates are reported. The HST key project that estimates an age around 13 billion years also stipulates +/- 10%, corresponding at most to ONE standard deviation, i.e. the 68% confidence level. This study is reporting their error bars at the 95% confidence level, which corresponds to two standard deviations, so the errors appear twice as large. The "13-14 billion year" age you report would have uncertainties of almost 3 billion years in either direction at the 95% confidence level. We have to compare apples to apples here!

      There is another very important point to recognize here. The HST Key project results (based upon Cepheid variable stars) is independent of the measurement/modeling of the ages of the oldest stars of Milky Way halo stars and clusters. Sure, both measurements each have significant systematic errors, but their uncertainties come from entirely different things! So the fact that they agree is quite reassuring. It also means that the measurements can be combined, at least to some degree.

      With the newest generation of instruments and telescopes observing the Universe from radio waves to gamma rays, there will be new, independent methods of measuring the age and fate of the Universe. Already measurements from Type 1a supernovae are narrowing the uncertainties in some cosmological parameters. Other methods that currently yield very large error bars, but will be pivotal in the next few years are gravitational lensing (a detailed description here) and the Senyaev-Zeldovich effect (some details here).

      When and if we get to the point where all methods yield the same result, we'll have our answer. In the meantime, if you just quote the formal results from just a single group, from a single type of argument/measurement, the systematic errors are going to be large, particularly when you're dealing with anything on cosmological scales!

  2. In related news... by selderrr · · Score: 3, Funny

    a team of researchers say that they are 95% sure Zsa Zsa Gabor is between 86 and 172 years old

  3. I remember this one!! by gurnb · · Score: 3, Funny

    42!
    . . . no, wait, that's the answer to a different question.

    --
    "This must be a Thursday, I never could get the hang of Thursdays."
  4. I can do better than that by Anonymous Coward · · Score: 3, Funny

    They're only 95% sure. I'm 100% sure the universe is over 1000 years old. I'm only 5% away from the top scientists! Woot!

    1. Re:I can do better than that by Skyshadow · · Score: 3, Interesting
      They're only 95% sure. I'm 100% sure the universe is over 1000 years old. I'm only 5% away from the top scientists!

      That raises a good point. When the hell did scientists start spouting off about how sure they were of anything? What ever happened to "Data heavily suggests" or "according to our new theory"? This is the second time in the last couple of days I've seen something like this -- a couple days ago there was a Cal professor on the radio saying her new study "proved" global warming was affecting animals and she was "100% sure" or her results.

      Hell, even the first class which introduced the scientific process in grade school was rather adamant about it -- the best you can "know" anything is to have a really well-tested theory about it (while accepting that you might still be wrong). This, OTOH, seems like a bad direction to be headed in, mindset-wise. My high school physics teacher would not have approved.

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    2. Re:I can do better than that by rknop · · Score: 5, Informative

      They're only 95% sure. I'm 100% sure the universe is over 1000 years old. I'm only 5% away from the top scientists!

      That raises a good point. When the hell did scientists start spouting off about how sure they were of anything?...

      ...My high school physics teacher would not have approved.

      Your dissapproval is based on misunderstanding To be fair, almost certainly the misunderstanding is not yours, but in the space.com article.

      "95% sure" doesn't mean that they're really 95% sure that they have absolute revealed truth. What it means is that, given the data and an understanding of the uncertainties in the data, and given the models and the uncertainties in the models, if we reproduced the experiment many times (i.e. we had many universes each of which produced stars that we could make the same measurements on), 95% of the time our data would give an age between 11.2 and 20 billion years old.

      That's what a confidence interval means. That's what 95% sure means. Unfortunately, the Space.com article makes it sound the way you've interpreted it. Obviously, yes, it means that this is under the assumption that our theories are correct-- of course, some of the theories in question are pretty well tested and well believed. But you are right that you can't prove anything, you can only disprove them.

      If you've ever heard Lawrence Krauss (the physicist quoted in the article) give a popular science lecture (he lectures a lot on the conflict between science and pseudoscience), he does emphasize this point. We do *know* some things from science. Even if it's a theory, we are pretty sure that some theories are right.

      But "sure" is not really "we have revealed truth". It is a misunderstanding of the term "confidence" used in scientific papers, which really means "the data are consistent with...", and quantifies how consistent the data are.

      -Rob

  5. a bit shocked by the figure... by haggar · · Score: 3, Insightful

    I am a bit surprised. Granted, I am no astrophysicist, but I knew that the Earth is estimated to be 4.5 billion years old. So I expected the universe to be much, much older than that.

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    1. Re:a bit shocked by the figure... by Rhubarb+Crumble · · Score: 3, Informative
      how quick do large stars explode?

      think more like 100,000 years or less, for anything above 5 solar masses. (1/lifetime) vs mass isn't a linear relation, far from it.

    2. Re:a bit shocked by the figure... by tconnors · · Score: 5, Informative

      Hmm... That does seem a bit small.


      Really? This figure has been known for at least ~30 years.

      1: there must have been a few big stars go bang to make all the elements of the earth.

      Yeah, I think one SN in your environment will bring the content of metals in your environment up to about 1/10^5 of the value found near the sun. Stars born in these regions are called population 3 stars, and roughly represent the first stars to be born. All they had at birth was hydrogen (75% by mass) and helium (25%). Then came pop 2 stars, then pop 1 stars (like the sun). ie, there have been roughly 2 generations before us. The first stars to be born were probably very massive, and these died very very quickly (lifetime goes down as a factor of hmmm, maybe mass squared - I can't back this up by data, and my memory is dead after all those ginger martini's, and I want to go home), subsequent generations were probably biased more towards low mass, but this is still very much subject to speculation and simulations (we know virtually nothing about star formation, and the initial mass function (the number of stars formed as a function of their birth mass - more massive stars are increasingly rare), even whether it varies with time)

      If the Earth is 4.5billion years old, then the solar system must be say 5 billion years old, how quick do large stars explode? must be say 1 billion - 3 billion years tops

      Far shorter. 1 billion years is the lifetime of a very low mass star - only say 2 solar masses (I can't be bothered running my program to find out the proper number). Normal SN happen about 10^6 years after birth, but depending on mass.

  6. Is the age of the universe definable? by Mr2cents · · Score: 5, Interesting

    I am no physics guru, but I've been asking myself this question for some time now. Since time was created with the big bang, and considering the theory of relativity, is it sensible to define the age of the universe? Did time behave as we are used to at the very beginning? If I'm right (feel free to correct me) when using the relativity theory you have to define a clock first and then you can measure time according to that clock. So what clock are they using?

    --
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    1. Re:Is the age of the universe definable? by BabyDave · · Score: 5, Interesting

      The "classic" way (due to Hubble) to guess at the "age of the Universe" was as follows:

      1. If we observe galaxies outside the Local Group, we see their light as being red-shifted. This indicates that they're moving away from us with some speed.
      2. There is a simple relation (called Hubble's law) between the recession speed v, and the distance r between us and the galaxy. This is v = Hr where H is a constant.
      3. Nothing can travel faster than the speed of light. So stick v = c into the above equation, and see what r is. Call this "the radius of the Universe".
      4. The "age of the Universe" is the time that a photon would take to travel a distance r

      Stick all that together, and you get t = 1/H. The problem being that finding H is fairly difficult - we can't accurately find distances to far-away galaxies. Estimates range from 50 km/s/Megaparsec to 100 km/s/Mpc

      So how else could we measure the "age of the Universe"? Well, we could work out the age of the oldest stars we can see, make some guesses at how long they would take to form from hot matter, and take that as our "age". After quickly RTFA-ing, I think this is what they've done, with a revised method to obtain the age of a star.

  7. Come on now by SubtleNuance · · Score: 3, Funny

    The universe is 4003 years old. Everyone knows that, details of the universe's creation can be found in the Bible.

    I mean really, when are these so-called scientists going to stop with this ploy to undermine The Truth.

    Jeeze.

    1. Re:Come on now by glh · · Score: 3, Interesting

      Although this is an obvious troll, I'll bite only because the date is wrong. The Bible would actually put the age of the beginning somewhere around 6,000 years.

      Good article, also trying to explain why current aging methods (such as carbon dating) are not accurate: http://www.answersingenesis.org/home/area/magazine s/docs/v23n1_earth_how_old.asp


      Main page for other articles: http://www.answersingenesis.org/home/area/faq/youn g.asp

  8. next year... by muyuubyou · · Score: 4, Interesting

    ...will be 9~26 billion.

    So they know they weren't accurate last year, and I have to "believe" them now.
    What happened to science? Do the word "proof" mean something anymore?

    At least, they should explain more in what are those estimates based instead of going for headlines with fancy numbers.

    1. Re:next year... by Rhubarb+Crumble · · Score: 5, Informative
      What happened to science? Do the word "proof" mean something anymore?

      This IS science. The only thing you can "prove" is that the universe exists NOW, and many people would doubt even that (that you can prove it, not that it exists). If you want absolute yes/no statements, try religion.

      All you can say in science is "given that assumption X is true, and our model is valid in these conditions, Y +/- Z will happen."

      One of the basic rules of proper science is that any measurement without errors or confidence limits is meaningless.

      At least, they should explain more in what are those estimates based

      I'm sure they do in the actual article. Although I agree with you that the headline sucks.

    2. Re:next year... by Vellmont · · Score: 3, Interesting

      When did proof mean anything in science? Proof has meaning in mathematics, but has very little meaning in science.

      With regards to believing "them", there is no "them" to believe. There's one guy with one method of estimating an answer, and another guy with a different way of estimating an answer. Supposedly the 13-14 billion year estimate produces a smaller range, and the 12-20 billion year estimate produces a higher degree of confidence.

      Your error is in expecting one simple answer to the question when we just don't know enough to give you that answer. The only answer that can be given is a more complex one describing the most likely answer, how confident we are of that answer, and how much we could be wrong by. (Ok, not literally we, since I'm no Astrophysicist, just someone who likes to think he knows something about what science is).

      --
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  9. Accuracy...? by altgrr · · Score: 4, Interesting

    "The universe is between 11.2 and 20 billion years old" could be interpreted as meaning "The universe is 15.6bn years old +/- 4.4 billion", which is +/-28% accuracy. To be 95% sure at this accuracy level isn't actually all that bad, when you think about the normal distribution, bell curves and the like. However, it does imply that there's some considerable discrepancy between each estimate, as you may well expect for something we don't really know much about.

    --


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  10. such accuracy... not by digitect · · Score: 3, Insightful

    Not trying to troll here (and speaking as a creationist), but I fail to see how a range this wide is helpful to anybody, let alone intriguing. This has always been my biggest fault with the theory of evolution: it will always remain indeterminate. Questions abound:

    • How can a range nearly equal to that of one of the factors itself be considered scientific?
    • What is "95" percent level of confidence" based on?
    • How do we know we're looking at "old" star clusters?
    • Couldn't they have been reformed once or twice in the expanding and collapsing process?
    • How will we ever guarantee that we can see enough of the picture to know we have a statistically representative sample?

    The article even states:

    Cosmologists, who speculate about the origin and operation of the universe as a whole, know they have their work cut out for them even as their understanding grows.

    I'm not trying to pessimistic, but it's always hard for me to believe any of these theories given that they seem to change on the decade. (And yes, I've been around a few decades.) If evolutionists could step back for a second and see the ridiculousness posed by articles like these, they might see that it comes off as not much better than science fiction or some 1960's Popular Mechanics dream concept of the future. The "evolution" of the theory of evolution itself should be evidence of its failure. (BTW, has anybody ever written about this?)

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    1. Re:such accuracy... not by Planesdragon · · Score: 3, Insightful

      # Couldn't they have been reformed once or twice in the expanding and collapsing process?

      Yes, although since they're no evidence of that or a mechanism that wouldn't create a "new universe", they can ignore it.

      If evolutionists could step back for a second and see the ridiculousness posed by articles like these, they might see that it comes off as not much better than science fiction or some 1960's Popular Mechanics dream concept of the future.

      The problem with evolution isn't that it contradicts creationism (pick your conciliation: God created the animals through evolution, God has a fast-forward button, God left the fossils so we'd understand how His creation will work, etc.). The problem is that it's taught as more true than religion, and the atheism aspect of evolution ("man evolved from apes") isn't seperated from the observable theory ("life evolves to the survival of the fittest.")

    2. Re:such accuracy... not by brian0918 · · Score: 3, Insightful

      The problem is that it's taught as more true than religion

      Rightly so. The theory of evolution better explains the course of events of living beings, and has evidence to back it up.


      and the atheism aspect of evolution ("man evolved from apes")

      How is this an "atheism aspect" of evolution? The Theory of Evolution says nothing about how life originated, just how it has changed over time.

    3. Re:such accuracy... not by griblik · · Score: 3, Informative
      • How can a range nearly equal to that of one of the factors itself be considered scientific?
      It's called error analysis. You essentially add up all the error factors in all the things you measured and it gives you a measure of how accurate your result is. Having margins this big isn't really that uncommon - last I looked, the hubble constant range was between 50 and 100 km s-1/Mpc.
      • What is "95" percent level of confidence" based on?

      A 95% confidence interval is a standard statistical test to see if a set of data could be part of another, larger set of data. Again, it's a measure of the accuracy of their answer.
      • How do we know we're looking at "old" star clusters?

      They're a long way away. The light from them has to have taken a long time to get here (speed of light being constant) so the picture we see of them is the one made up of light that left a long time ago. You can also tell they're old because of their composition, which brings us to your next question...
      • Couldn't they have been reformed once or twice in the expanding and collapsing process?

      They might have been, but it's a simple thing to check. The early universe was composed almost entirely of hydrogen, which they converted to helium. When they died, their helium was scattered and helped form younger stars, which started converting the helium into heavier stuff. If you check the light coming from a star, and it has heavy (ie heavier than helium) element absorption lines, it's formed at least from the matter of an older, dead star, and so has to be a second or later generation star. If it doesn't, it's an original.
      • How will we ever guarantee that we can see enough of the picture to know we have a statistically representative sample?

      We can't. It's the basis of science. You make your best guess based on what you've got, and you defend it until someone proves it wrong. Then you take their best guess and try to come up with something better...

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    4. Re:such accuracy... not by revscat · · Score: 3, Flamebait

      Not trying to troll here (and speaking as a creationist), but I fail to see how a range this wide is helpful to anybody, let alone intriguing. This has always been my biggest fault with the theory of evolution: it will always remain indeterminate. Questions abound:

      Which have answers. Read a book. And no, by "book " I do not mean "currently fashionable creationist diatribe."

      I'm not trying to pessimistic, but it's always hard for me to believe any of these theories given that they seem to change on the decade. (And yes, I've been around a few decades.)

      Which is more desirable: Theories that change based upon newly available evidence, or theories that insist upon changing the data to fit the theory? I tend to prefer the former, thanks.

      The "evolution" of the theory of evolution itself should be evidence of its failure. (BTW, has anybody ever written about this?)

      Probably, but fools abound. One of the primary reasons that science is so much better able to ascertain truth, such as it can, is because it is not married to dogma. (Dogmatists tend to claim the opposite, of course. I'll take it as given that you do as well.) The evolution of theories is a feature, not a bug. However, the underlying premise of evolution -- that species change over time in response to competitive pressures in their environment -- has not changed since Darwin proposed it. Tweaks have occured on the edges; however you may wish these changes to show its invalidity, they only serve to strengthen the underlying theory.

      And while we're talking about ridiculousness, let's talk about moody Babylonian sky-gods creating the entire universe in 6 days a few thousand years ago... Hmm... You think your religion hasn't evolved over time? That the things you believe were believed by Christians 1500 years ago? 500 years ago? 50?

      Read a book.

    5. Re:such accuracy... not by cje · · Score: 5, Insightful

      The problem is that it's taught as more true than religion, and the atheism aspect of evolution ("man evolved from apes") isn't seperated from the observable theory ("life evolves to the survival of the fittest.")

      If you believe that biological evolution predicts that "man evolved from apes", then it is perhaps unsurprising that you have problems with the theory. Let us cut the creationist hyperbole and consider what it really predicts: that mankind and modern apes have a distant, common ancestor. How is this the "atheism aspect" of evolution? What does this say about the existence or nonexistence of God? Be specific. Accuracy counts.

      Come on, now. Be brave and say what you really mean: twin-nested common descent is not the "atheism aspect", it is the "anti-Protestant-fundamentalist aspect" of evolution. That would be an accurate statement. If you believe that the entire universe is only 6,000 years old and that the book of Genesis is the literal truth, then you're obviously going to have problems with biological evolution (and most of the rest of the natural sciences, as well.) However, you should know that you are in the minority; the vast majority of Christians have no problems reconciling their faith with obvious scientific fact.

      Science education is about the presentation of the current state of the art of various fields of study. This includes chemistry, physics, and yes .. biology. Evolutionary common descent happens to be part of the state of the art in biology (and has been for some time.) That's why it's taught in schools. There are millions of biologists, botanists, zoologists, etc. around the world. If biological evolution is as flawed as some people claim it is, then you would think that there would be massive scientific outcry against the theory. Instead, what we have is a small but vocal handful of "creation scientists", the majority of which are located in the U.S. and just happen to be (surprise!) Protestant fundamentalists.

      What does this tell you?

      Finally, to get this more on-topic, it should be noted that evolution has absolutely nothing to do with the formation or the age of the universe, the formation or the age of the Earth, the validity of the Koran, or the score of yesterday's Giants-49ers game. It is a biological theory that discusses changes in the gene pool of a population over time. That's all it is.

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    6. Re: such accuracy... not by Black+Parrot · · Score: 3, Insightful


      > Not trying to troll here (and speaking as a creationist), but I fail to see how a range this wide is helpful to anybody, let alone intriguing. This has always been my biggest fault with the theory of evolution: it will always remain indeterminate.

      You can get started on your education by learing the difference between cosmology and the theory of evolution.

      > How can a range nearly equal to that of one of the factors itself be considered scientific?

      Would you prefer that they gave a narrower range that they couldn't justify?

      > I'm not trying to pessimistic, but it's always hard for me to believe any of these theories given that they seem to change on the decade.

      Unlike creationists, who cling to their ideas even though we had the evidence to refute them 180 years ago?

      You should learn to understand theories as models that explain what we see. Scientists are obligated to revise their theories as more information becomes available.

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  11. Re:Age of the Universe or of Matter? by Oddly_Drac · · Score: 3, Interesting

    "Well, with all of this new revelation that the universe is made up of 95% of "dark matter","

    I.e. 'cold' matter that you can't pick up easy by looking for it.

    "do we really know that dark matter didn't create the hydrogen atoms?"

    It did. It's protons, neutrons, electrons, WIMPs, MACHOs and other exotica that it's really hard to construct in a lab less than several light years in size with easy access to a stable fusion furnace and near zero-g with ample parking. One of the newer ideas is strange matter, lumps of superdense collections of strange quarks.

    The 'big bang' is simply a method of delineating the 'before' and 'after' of a single event...before...nobody knows...after, there's a fairly tight sequence of events that hang together quite well given the constants that can be tested on earth and our basic assumptions about the universe. That's not to say it's correct, but it's probably darned close.

    --
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  12. Re:Hype by reitoei1971 · · Score: 4, Insightful
    That way, instead of the general public just believing the "almighty scientists," they can look over the research themselves and come to their own conclusion pertaining to the accuracy of the conclusions.
    I would doubt that very many people of the general public would care much less take the time to *read* and understand a scientific paper. Such is the tragic nature of our world. People love hype and hate substance!
  13. Its always nice to know... by lobsterGun · · Score: 3, Funny

    ...the upper limit on the age of the the fuzzy leftovers in the back of my fridge.

  14. Contradictions by Dusabre · · Score: 5, Interesting

    Yes you can have it both ways. Otherwise:

    The Bible states that the world is flat. Can you accept its round or are you suggesting that you can either be a Christian or a heathen 'round-worldist'.

    Oh and since Adam and Eve are key to religion... then what about those people who weren't descended from them, those people that Cane was worried would smite him after he killed his brother. And those people whose daughter he married and lived with in the land of Nod.

    Etc, etc, ad nauseam (see (Bible Contradictions))

    The Bible contradicts itself constantly. You have to be able to rationally treat those contradictions. I can call myself a Christian without treating the Bible as literal truth. Can you?

  15. Re:Age of the Universe by reverseengineer · · Score: 3, Interesting

    This ties in with a /. article that was posted a few days ago about a possible modification to the Special Theory of Relativity to include the Planck energy, which can be found here . When you start to talk about the very beginnings of the universe, the various Planck dimensions come into play, and set an upper limit to what can actually ever be known about the conditions at the start. These dimensions are described by combinations of Planck's constant h, the speed of light c, and the universal gravitational constant G- for instance, Planck length is (Gh/c^3)^1/2, which equals roughly 10^-33 cm. This was roughly the size of the entire universe at the Planck time, Gh/c^5)^1/2, which is about 10^-43 seconds. From these arise other scales such as the Planck energy, 1.2 x 10^19 GeV and the Planck temperature, 1.4 x 10^32 K. At these conditions, the laws of physics as we know them did not apply. There are a variety of ways to explain why this should be the case. In many Grand Unified Theories, the four fundamental forces (gravity, electromagnetic, strong, weak) are considered to be aspects of a unified superforce. There is evidence to back this up- at energies that can be achieved in particle acclerators, the weak and electromagnetic forces merge to form an electroweak force. The strong force is expected to join in at about 10^14 GeV, well beyond our present reach, unfortunately. Gravity, oddly enough the weakest of the forces (but with infinite range) holds out until the Planck energy. A universe at these conditions cannot be described by known physical laws- it is pure chaos. The universe is too hot, too dense for particles as we understand them to exist.

    Another way of looking at the universe at Planck time arises from the equations for the dimensions themselves. The relationships among the equations are no accident- there are Heisenberg Uncertainty relations that exist between many of the quantities involved. As such, you can imagine the universe at Planck time to have the interesting property that completely random quantum fluctuations will occur, and will occur on the order of the Planck length. The thing is, the Planck length is also the size of the universe at this instant. So in essence, we're talking about a period where the universe is completely undefined, and it becomes meaningless to talk of things like particles and forces and even space and time itself. Now, clearly, the universe exited this phase somehow- else the universe as we know it could not exist. Why did this occur? Well, since an experiment at such energies is not likely to be possible, this question is perhaps best relegated to the realm of metaphysics. As to what happened prior to this period, there really was no "prior." The four dimensions (3 space, 1 time) that we know and love are a part of the whole universe package- the universe is not just expanding its space, but its spacetime. In fact, there are some theories (like supersymmetry) which predict the existence of many more dimensions, like 10 or 26 (they make the math work out nicely). As to why we cannot see them now, the idea is that extremely early in the history of our universe, the rest (meaning those other than the 4 we notice) folded up on themselves, and are currently sized (which brings us back to) on the order of the Planck length.

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