Universe Race

Actually, I have the same question. Probably naively I would think that each Planck volume (is there such a thing? - in any case, I'm trying to refer to the smallest unit of space) could only contain a single fundamental "something", whatever that might be, whether quarks or superstrings or whatever. Once all Planck volumes in the universe contain a "something", then isn't that the greatest possible density? And is this at all related to why current models have difficulty describing what happened before T=10^-43?--Percy

It's easy to become confused when you participate with so many short messages. Taz was responding to your Message 28, which is not the one that asked about black holes. It asked how all the mass and energy of the universe could have been compressed into something the size of a pea. Taz even quoted this above his response, and the message links associated with his reply clearly showed that he was replying to your Message 28. Why don't you give Taz's Message 32 another read with this in mind - you might find it makes more sense when you keep your contexts straight.--Percy

I think you're mixing two different analogies together. I haven't heard of the cake analogy, but I have heard of the bread analogy, useful because bread rises (expands fairly uniformly) as it bakes. But maybe cakes do the same thing, shows what I know about baking.Anyway, in the bread analogy the bread dough is usually filled with raisins (or something similar) which separate from one other at a velocity that increases with increasing distance as the bread rises during baking.The cone analogy is different. It matches the cone's apex to T=0 with T increasing as you advance away from the apex. Typically the cone is described as increasing in diameter with distance from the apex in a manner analogous to the rate of expansion of the universe. Expansion is indicated by increasing cone diameter.The balloon analogy is merely a 2-dimensional example that is fairly equivalent to the 3-dimensional bread analogy.--Percy

But as we go back in time our pea becomes smaller and smaller. Going by your figures, the observable universe would still fit easily in something the size of a proton, but as we continue back in time we eventually progress to where each point in Planck space has the Planck energy. What then? Is this where current theory breaks down? Or is something else responsible?--Percy

--Percy

Saying, "We don't know how the universe originated," is not the same as saying, "The universe had no origination."Saying, "We don't know what happened before T=10^-43," is not the same as saying, "Nothing happened before T=10^-43." It is also not the same as saying, "Nothing existed before T=10^-43."I stand as amazed as I think everyone else is at your ability to derive erroneous conclusions from "We don't know." Once again, just in case it wasn't clear, "We don't know what happened before T=10^-43," does not mean, "The universe wasn't there before T=10^-43." For some strange reason known only to you, and perhaps even you don't know, you keep saying this over and over again despite everyone telling you it is wrong. Some parts of our universe are retreating from each other at the speed of light and faster, but only because they are so far apart that there is much space between them, and a great deal of space expanding at a relatively slow rate adds up across the distance. But space is not expanding at the speed of light.There was a theorized period during the early universe when space did expand at a huge rate often described in popularizations as being faster than the speed of light, but I'm guessing that Son Goku and Cavediver would tell us that it's not really meaningful to describe it that way. Only if during inflation two adjacent points in space became separated by more than 186,282 miles just a second later would this seem to be true in my view. Suffice to say that space was expanding then at a much greater rate than it is expanding today. Maybe Cavediver and Son Goku will comment on this. Everything you find about matter and energy says they can't travel faster than the speed of light. Space/time, the very backdrop upon which matter and energy play out their dance, has no such restriction. Once again, space is not expanding at light speed. In fact, space is expanding so slowly now that gravitational attraction has no problem keeping matter in close proximity. It is only distantly separated objects where the gravity between them is weak that the slow expansion of space creates increasing distance between them.--Percy

Hi ICANT,If you're saying that all the kinks in the theories explaining the Big Bang haven't been ironed out yet, I think cosmologists everywhere would agree with you. That's why it's an incredibly active area of research.Discussion in this thread has recently shifted from the topic to your approach to discussion, and I'm finding it very difficult to avoid doing the same thing. The common theme running throughout this thread isn't any cosmological issue, but your inability to put into proper context anything that you read about cosmological issues, and your resistance to having your misconceptions corrected.Let me provide an example. In your last post you confused the scale at which the universe should appear "homogeneous and isotropic", which is very large, with the much tinier scale of clumps of galaxies and the dark matter which influences their structure. Dark matter wasn't proposed to explain the large scale structure of the universe, but to explain why on a much, much smaller scale that spinning galaxies don't fly apart. Where dark matter fits into the large scale structure of the universe isn't something that we understand much about at this time. But no one's sticking their heads in the sand. The shortcomings of current theory are written about all the time. Popularization after cosmological popularization appear in the bookstores because laypeople are fascinated by the issues and problems. A number of them sit next to me on my bookshelf.It may be that your unfamiliarity with science combined with discovering that science doesn't know everything and that there are significant unanswered scientific questions is causing you conclude that something's rotten in Denmark. Well, good luck finding the rotten core of an effort that is only asking the question, "How do we explain what we find in the cosmos?"You're taking a shotgun approach where you raise a few questions, then you ignore the answers and raise a few different questions, and you never stay focused long enough on any one issue to understand it. I suggest you slow down and attempt to understand each issue before moving on. For example, you could spend more time on the "homogeneous/isotropic at large scales" issue and learn why it isn't directly related to dark matter.To everyone: If I could slip briefly into admin mode, it raises the concerns of moderators when threads turn from discussing a topic to discussing the participants. If people could, please articulately express any complaints you might have in the Windsor castle thread and leave the discussion threads for discussing their topics. This advice goes to me, too, which I was unfortunately unable to follow in much of this post.--PercyEdited by Percy, : Typo.

First, note that Son Goku wasn't talking about the multi-verse scale. This thread is about the universe, our universe, just the one universe.Second, homogeneity and isotropism are expected only at the largest scales. The webpage you linked to earlier, Wikipedia on the Cosmological Principle, was very explicit about this: I think you need to spend more time studying and less time concluding. The structures you mention are also far from a large scale, as people have been telling you. Your certainty is an artifact of your lack of knowledge. It was an open letter published in New Scientist, not an article. It concluded with an appeal for funding for non-mainstream cosmology theories. It's leading signatory was Halton Arp, known for his rejection of the red shift's correlation with distance. He thinks quasars are local objects ejected from galactic cores. Time and again he has identified rapidly receding objects (which accepted theory says must be distant) that appear to be in front of nearby objects, and which time and again improving telescopes have shown to be behind the nearby object. Arp has trouble getting funding because of his well-established habit of being wrong. If you were working at gaining familiarity with the subject matter you would have discovered this. The observational evidence says that it's there. That we don't happen to know what it is doesn't mean that it isn't there. Just like an Unidentified Flying Object, where the fact that we can't identify it doesn't mean there was no flying object at all, the fact that we do not at present know the nature of dark matter doesn't mean it doesn't exist. This is obvious, basic stuff that anyone should understand.About dark matter dictating the structure of the universe on the grandest scales, the hypothesis mentioned in the Wikipedia Great Wall article that you cited, that seems like stepping pretty far out on a limb given the current state of knowledge, but I'll wait to hear what Cavediver and Son Goku have to say.--Percy

Except for the fact that dark matter isn't postulated to hold the universe together, and that the scale of the large-scale structures you mention is relatively small, your list is okay. Three things are apparent from your list:

1. There is much that science doesn't know. Of course, we knew this already. If this weren't true there would be nothing for scientists to do. The job of scientists isn't to come to message boards to lord it over laypeople. Their job is to conduct research into those areas we don't yet understand. To indict science for there being things we don't yet understand makes no sense at all. It would be like calling a 1st grader stupid because he can't yet do calculus.
   ​
2. You think the list contains contradictions. It doesn't.
   ​
3. It's easy for those first approaching the subject to make mistakes, often the same ones over and over again.

The most significant thing you say is this: This contains the most fundamental misunderstanding of all. The Big Bang isn't science because it's what scientists want to believe. It's science because it's what scientists have uncovered about the universe through observation, analysis, prediction verification and replication. Whether or not we ever figure anything out about the how of the Big Bang, we still know it happened because when we look out into the universe that's what we "see", where "see" is only in quotes because our eyes on the heavens are all technology these days.So if tomorrow it is discovered observationally that the universe really isn't homogeneous and isotropic on large scales, then we'll just have to accept that and adjust our theories accordingly. It would be difficult to reconcile with what we already know of the Big Bang, but facts is facts.You, of course, would draw from such a discovery the conclusion that something's rotten in the Denmark of science. You've examined the processes of science and discovered (gasp!) that science is tentative and doesn't know everything.You seem to think we're claiming that we already know everything. We're not. We're just pointing out that not knowing everything is not the same thing as not knowing anything. If it did, then the fact that you don't understand cosmology when it comes to dark matter and galaxies must mean that you don't understand anything at all about cosmology. But you don't buy that, right? Well, we don't either. So why are you pointing to things science doesn't know, indeed acknowledges freely it doesn't know, as if it calls into question things science has strong evidence for.We have a pretty good idea of what happened back to about T=10^-43 seconds, and we have some good theories about how it happened, but of the time before that our knowledge and understanding is extremely limited. Them's the facts.--Percy

Imagine this grid represents all of space, note the two stationary objects "x" and "y" in opposite corners: Now space grows by a factor of two and looks like this: "x" and "y" haven't moved, but space has expanded between them and they are now more distant.This is the way in which Cavediver meant that nothing is moving. Space is expanding and carrying the objects along for the ride. The objects themselves are not moving with respect to space.--Percy

Hi ICANT,Let me just address the end of your post, where you say: I already explained. I said in the very message you replied to, Message 292, "The structures you mention are also far from a large scale, as people have been telling you."Rather than replying with yet more news excerpts about the Botes void and the hole in the universe and asking, "Please explain," why don't you engage the discussion and ask meaningful questions.Perhaps you could ask, "If the scale of these structures isn't large enough to affect the large scale homogeneity and isotropism of the universe, how large would a structure have to be then?"Good question. Cavediver? Son Goku?--Percy

Let me rephrase your question: Is it possible that our data can be explained by the explosion of matter and energy into preexisting space instead of by the expansion of space itself?The answer is no, it cannot. The most obvious evidence against it is the Cosmic Microwave Background Radiation (see CMBR at Wikipedia) which would not have its unique characteristics if our current universe where the result of matter and energy exploding into preexisting space.--Percy

Before I take a quick look at these, let me ask you a question. Did you understand the responses to your previous "pieces of evidence?" And your "pieces of evidence" before that? And the ones before that? And those before them?In other words, what is the point of anyone responding to your "pieces of evidence" if instead of spending the time to understand the responses you just go off and find more "pieces of evidence" that just raise pretty much the same issues?By "study and learn" we don't mean go off and find more excerpts that you don't understand. We mean work to understand the ones you've already provided. All you're doing is lengthening the list of extremely similar excerpts about things you don't understand. You're quoting an article from the University of Michigan school newspaper from May of 1995. That issue also included the news that Gary Moeller had resigned as head football coach as well as advice about what to do in the event of a tornado.You should be seeking recent, well informed technical articles. This is none of these. Don't cast your net too far. There are probably billions of words on the Internet about the Big Bang. Every kind of weird belief is represented out there somewhere, and if you're not discriminating you're just going to waste a lot of time. Stick with mainstream technical journals, magazines and websites, and don't go too far back in time.I have no idea why this article says that dark matter could be "the glue that holds the universe together." It was an obviously very speculative hypothesis 13 years ago, and it just as obviously hasn't panned out, not in the form of supporting evidence, anyway.But what would it mean if it turned out that dark matter *is* the "glue that holds the universe together?" Are you thinking that such a discovery would somehow invalidate the evidence that supports current theories of cosmological origins?Anyway, the bottom line is that there is very little we understand with any degree of confidence about dark matter at the current time. We know it exists because we can see the effect its mass has upon the structure of galaxies, but beyond that we know very little. In this case the article's author obviously does not mean to imply that gravity holds the universe together. He's merely stating that gravity is the attractive force within the universe.Like I said before, there are literally billions of words about cosmology on the Internet. Not everyone is going to express themselves perfectly clearly every time. If you're going to scour the Internet looking for sentences here and there that reinforce your misinterpretations, you will have no trouble finding them. But finding people who actually have detailed and accurate knowledge of cosmology has got to be a rare event, but you're for the most part rejecting this blessing. The above appears wholly accurate. You said, "I don't believe like you do." For scientists it isn't a matter of belief but of what the evidence and replicated experiments/observations indicate. Reaching conclusions from evidence is one thing, believing something without being able to offer any evidence is another. Now you're missing the entire point of this website.No one's trying to talk you out of your religious beliefs. No one is lobbying for equal time before your congregation to preach the Big Bang, an ancient earth, and evolution. If you want to believe Genesis is how it happened, that's fine by all of us here.Problems only arise when creationists claim their religious beliefs are actually scientifically valid principles that should be taught in public school science classrooms, but when lobbying school boards they can't admit that the principles they advocate are religious in nature, so they drop references to God and Bible in such venues.So if you want to believe that Genesis is how it happened, fine, no argument from me. And I have absolutely no worries about creationists who go to schools boards and argue that Genesis is what should be taught in science class about cosmological origins, because not a school board in the country would ever think they could get away with such a blatant violation of the First Amendment, no matter how sympathetic they might be to such a proposal.EvC Forum exists to examine creationisms claims to be legitimate science. Once you start citing Genesis you've lost that debate outright, so go ahead and cite Genesis all you like. But not here in the science forums, okay?--Percy

This isn't a semantic game. My conclusions are supported by the evidence, yours are not. Your conclusions are simple unsupported beliefs inspired by Genesis. If you don't want your religious beliefs examined then in the future I suggest not introducing them into the discussion, which is a good rule of thumb for the science forums anyway. Science has no direct evidence for what happened at T=0 and shortly after, and what theory we have tends to break down at that early time, so in the absence of both evidence and theory, science says we don't know.You, on the other hand, though also having no evidence or theory to guide you, claim to know. Whether right or wrong, such conclusions are inherently unscientific because they have no empirical base, and the phrasing and terminology reveal an unfamiliarity with basic physics. I see no point in being picky, so I'll just say that this seems consistent with currently accepted views within cosmology. This is contradicted by the available evidence, which indicates that the universe is flying apart.You said this to Dr Adequate: I see little hint of a desire for information. You're repeating the same mistakes now as when you first began participating. If you want to construct your own cosmological theories you might want to at least make sure they're consistent with the evidence already in our possession, which means, in case you weren't sure, learning about it.Guth Bless,--Percy

Just in the interest of correcting misinformation, a couple cosmologists have been participating in this thread, and a couple other people seem to have a high degree of familiarity with the field.--Percy