I was watching a show on the Hubble Telescope in which several NASA scientists commented on one mission of the Hubble is to determine how old the universe is. (Universe meaning everything out there… A pretty big area to be sure)
If I understand the show correctly, they calculated, over a period of five years, how fast everything they could see was expanding. With this information they figured the entire universe was 12 billion years old.
So, that works on one scale. We can figure this by everything we can see all moving away from one point -the area we just happen to be in. But does standard science thought figure there is nothing else outside of that bubble of what we can see? I always figured the universe has no edge, it just kept going and going and going. Like a massive pool with no sides. Our regional universe (for the lack of a better term) covers all we can see expanding from a big bang. But in relation to the very big, extremely huge picture, that regional universe is only the size of a very tiny leaf in the shallow end of a swimming pool. There are other regional universes -say way over in the deep end- that have also undergone a Big Bang and are expanding as well.
Just like our galaxy is just one of millions, our “regional universe” created from our big bang is just one of millions more.
Does popular science really limit the entire universe, meaning EVERYTHING out there, to just what we can see, and the one Big Bang covers it all -the entire EVERYTHING? Or does the popular understanding say yes, there is more out there outside of what we can spot -so far away we will never be able to see it with any telescope?
(I’m just going to put this in GD in case people want to bring religion or other fun stuff into the thread)
I’ll take our “universe” is 12 billion… I’m fine with that I suppose. I just find it hard to fathom nothing is outside of our field of vision. It seems so flat earth to me.
If those other regional universes are so far out that they can’t possibly be detected by us, that’s roughly the same thing as there not being other regional universes. What science can’t measure, science can’t describe. The regional universe theory has all the evidence of religion.
Like religion, that doesn’t mean that regional universes can’t exist. It only means that science can’t say anything about them.
You are just addressing what we can SEE through a telescope. If you look at the entire electromagnetic spectrum, you’ll find that what we can SEE is a tiny fraction of the whole spectrum. What you can hear is even a smaller portion of the spectrum. There is a vast area out there beyond our visual and aural senses that we are incapable of perceiving as humanoids.
And then there are people who believe in God, not realizing that what they read in the Bible, Qoran and Torah is only limited by what they can see or hear-- which was inculcated into them by their parents or environment. They have this strange idea of “The Creator”, while they are so limited in their senses to even perceive what is out there in the vast electromagnetic spectrum of which what we see or hear is a very tiny part.
How do you educate this masses of 6 billion people who blindly “perceive” and follow a bunch of witchcraft, superstitious, fairy-tale promoters such as Popes, Ayatollahs and Rabies.
I say let’s get rid of the concept of GOD and all religions. Let us start eradicating ignorance. Let us start admitting that we have such miniscule sensing and processing capabilities in this stage of our brain evolution that we have no business in creating “GOD” to be “The Answer” to our unanswered questions.
We humanoids probably need another 12 billion years to go before we evolve into a totally different species that can possibly perceive “The Answer”, if any.
OK. Reality check. We are back in 2004. Let the Jews and Arabs kill each other. Let the Hindus of India and the Muslims of Pakistan unleash the nuclear weapons upon each other. Let the Catholics and Protestants in Ireland kill each other. Let the Capitalist Right-wing Religious Rights in the US bring about the Armageddon – all under the name of GOD, Allah, or whatever BS fairy tales their belief systems based on their limited senses at this stage of human evolution. And SDMB is trying to eradicate that kind of ignorance? I say GOOD LUCK.
Well, leaving aside the anti-religion rant of rather poor quality preceeding this post I’ll give the OP my best shot.
Until you have evidence of these other regional universes (and that will be a major scientific breakthrough) they remain unnecessary complications to cosmological theory, which works pretty well as it is.
Firstly, the very definition of “Universe” includes ALL of space and time. Your kind of objections apply well to galaxies and even the larger galactic clusters, but not to the universe.
Also remember that the Big Bang was not an isolated event in one spot of space; it was the appearance of space and matter simultaneously everywhere. What we call space, everything we see in the universe, was at one time contained in a point. The only “edge” you will find in the Universe is the Big Bang.
Said that, I suppose for speculative purposes it may be dimly possible (hey everything is possible) there were other Big Bangs “elsewhere”, but presently we think that all matter in the observable universe originated in the Big Bang. Since a/the Big Bang is considered a rather high energy event, the only conceivable reason for not detecting other Big Bangs thus far is that they lie far away, and the electromagnetic radiation bearing information from those events has not had enough time to reach us yet.
Effectively, that means these universes don’t exist. But this and the above paragraph are simplistic pre-Relativity (intuitive) speculation not compatible with modern cosmology, and we know that on the scale of the very small (quantum) or the very large, common intuition is practically useless.
Additionally, there are some interesting dicsussions on the nature of space, and whether space as a concept would exist at all if there is nothing to occupy it/curve it/create it/etc.
Remember, General Relativity tells us that gravity is merely a distortion of space and time; one of three models of this distortion defines the curvature as positive and therefore finite, like the surface of a planet. The other two models, negative and flat, postulate an infinite universe, and from what you say I think you intuitively assume that the applicable model must necessarily be the flat one, but intuition does not always serve one well in physics. Matter, and the average density of matter, have an effect on the very geometry of the universe. It is unclear how “other” universes would (or even could) exist when you consider these data. Even assuming they did, we would be extremely unlikely to ever learn about them. Ergo, they become unknowable entities and events, and constitute unfalsifiable hypotheses, so they might as well not exist.
An unfalsifiable hypothesis is one that cannot be proved wrong by any means; it is always correct; this is of course useless to science because the hypothesis cannot be tested for veracity and accuracy, and has zero epistemic value.
“Popular science”? What is that supposed to be? The Universe is indeed the observable universe, with the farthest we can see termed the “horizon” and there are a number of ways we can observe it.
Here is the kind of work astronomers have been engaged in:
Basically it discusses three dating methods: analyzing the age of the chemical elements, the oldest star clusters, and the oldest white dwarves. As you can see the results of the various methods are not precisely identical, but they are all roughly within range.
Here is NASA’s Wilkinson Microwave Anisotropy Probe’s (WMAP) take on the problem:
One of their most significant achievements was forming an image map of the oldest electromagnetic radiation available, effectively taking a snapshot of the universe when it was only 379,000 years old., so these guys know a thing or two about cosmological dating. They estimate the age of the observable universe at 13.7 billion years (error: +/- 1%)
They’ve detected the ignition of the very first stars when the Universe was about 200 million years old. Fascinating stuff.
Just a bit of advice. I’m sure you have some valid points to make, but this style of rhetoric is likely to raise the hackles of both members and TPTB. It’s just not board style. Not that I’m perfect myself…
would AFAIK contradict Big Bang Theory (which is fine, but such things would have to be proven). As another poster indicated, according to BBT, the BB brought space and time themselves into being. In other words, there was not a pre-existing void into which the BB singularity expanded; the singularity was ALL that existed.
Hence, again according to the theory, there was not a great big void into which two or more singularities could have expanded. On the contrary, if two singularties had gone bang, there is no reason why they should have had any connection at all. The other singularity might have formed a universe completely disconnected from our own–which, as another poster indicated, would mean that this universe does, as far as we are concerned, not even exist.
Still, I read an article last year (tried to find the cite but couldn’t–help?) in which a theory was proposed very similar to that of the OP: to wit, that bubble universes exist (in the same space) quite far from each other, each of which represents a possible quantum universe such that every possible combination exists (i.e., in one of these universes you are now reading a book with a blue cover, blah blah). I think the theory is on crack and have several arguments against it, but it’s out there.
If these “other universes” (strictly, as you say, other “regions” of the combined whole) are not observable, indirectly detectable or indeed falsifiable in any wayb then they may be mathematically appealing but I’m afraid they can no longer be considered “science”. Science deals only with what can be measured, observed and falsified.
As for some of the misleading phrases flying around, such as that the Big Bang “happened” or a universe “undergoes” a Big Bang or that the Big Bang “created” the universe, I’ll refer you to this thread:
I would like to mention that there is a growing number of scientist around the world who claim that the current paradigm that we’re living in an expanding universe caused by a Big Bang is incorrect. They have pointed to observations where “areas” of the known universe is older than what the universe could possibly be if it was a Big Bang universe.
I don’t know whether that number is “growing”, Alien. The number of Staedy State advocates has certainly shrunk to near zero since the galactic redshift was observed!
That some stars were apparently older than the 13.7 (not 12) Bn years of the universe has dogged modern cosmology for decades, but this is thought to be due to some misunderstood aspect of star detection/age estimation rarther than a serious hole in the Standard Model.
I’m no expert on space, but it’s a fascinating subject, one which I would like to get into at some point. I’m not saying the BB theory is incorrect, but it does leave a lot to be explained.
Erm, I would be careful about appealling to the authority of The Watchtower or a science-fiction fanzine, Alien. Nevetheless, there are some stars which appear “too old”. I believe there are many competing hypotheses which seek to explain this, but they don’t necessarily impugn the entire premise of the Big Bang.
Our understanding of the early universe has changed a lot since then. We now believe that the universe has up to 5 times as much “dark matter” as normal matter. This makes galaxy formation proceed faster. Still, galaxy formation in the early universe is a hot topic of research and by no means have all questions been answered.
I think most astrophysicists would not agree that the small and large redshift objects are directly connected. They just happen to appear near each other in the sky from where we’re looking.
Much larger regions have now been surveyed, and on these larger scales the universe is very uniform. The large structures mentioned are not unexpected in early universe scenarios that include dark matter.
No quasars are “reliably dated”. Quasar formation is still poorly understood. Some globular clusters can be dated to about 14 billion years old. But including dark matter and dark energy in the models of the expansion of the universe seems to resolve the difficulties in timing.
Actually, it is completely correct in that it is observed to be true. That is to say, the Big Bang is still going on! It’s simply the result of the fact that the universe is expanding, there is a CMBR, and there is a primordial abundance of nucleons that we observe to be in accordance with an expanding universe model.
As to the details: you’re right, there’s a lot of 'splaining left to do. However, what do know is the following:
The universe from the time of inflation is roughly 13.7 billion years old.
The universe is made 96% out of stuff that we have never seen or observed except by means of this stuff’s effect on astronomical bodies. ~30% is dark matter (stuff with mass but no cross-section for the other three fundamental forces of the universe: electromagnetic, strong, and weak), and ~70% is dark energy (energy that is intrinsic to spacetime itself and has the peculiar property that as the universe expands it increases thus exhibbiting a negative pressure).
The universe’s atoms are 90% hydrogen by number and 10% helium with a small, small fraction of the other elements.
These are all observed facts, plain and simple. There is no “disproving” this theory as it is solely observation.
Here’s some issues with your first article:
Freedman’s numbers didn’t hold up. It turned out that she had a systematic problem with her estimate. Correcting for it gives a universe of the correct age. By the way, the 14 billion year estimate for stars comes with a rather hefty 1-2 billion year error bar making them consistent with the measured age of the universe I quoted above.
Not a problem at all. Current numerical models reproduce the filaments and voids very well.
This question is resolved by the fact that Dark Matter doesn’t interact with light. That is to say that while the light is uniform, the dark matter is not because it hasn’t been kept in collisional equilibrium with the rest of the universe. Instead it has been steadily clumping since the beginning of time. From this seed of Dark Matter, galaxies come to rest and give us the amazing structure we see.
The so-called “End of Greatness” has been observed: that is to say that we now see where the end of structure lies and it means that on the largest scales the universe is as homogeneous as it needs to be for the big bang to be correct.
Linde’s model of eternal inflation is a certainly one way the existence of the universe and the Big Bang is resolved. There are others and there is no way to really tell which is right.
One thing I have to say is that some people take the “Big Bang” for more than it is. It is not the last word in science on The Question (you know, the one about the life, the universe, and everything): it is simply the most general description that we have available that fits observations. This is not to say that the Big Bang is “incomplete”. On the contrary, it’s the MOST complete thing we’ve got or can hope to get with current observations. Will future observations change things around? Absolutely: but realize that the fact that the universe is expanding, was really dense and hot at one time, and has a predictable fraction of stuff that came from this soup of primordial particles is here to stay. AFAIAC, that is the Big Bang.
From your second cite:
Inflation is the answer to this problem. We have evidence for inflation now not only from the flatness, smoothness, issue but also from evidence directly from the WMAP satellite that confirms our universe had to go through a certain type of expansion that “inflated” the universe from a factor of 1 to a factor of 10^10^30. We don’t know the details of inflation, but it is a natural consequence of a scalar field at a high potential universe: it that way we’ve got an answer to the complexity problem too because no matter what kind of field you start with inflation give us the universe we see. This isn’t just a convenient fudge factor, either. One can come up with one’s own inflationary model and the results are extremely unsensitive to the initial conditions you choose!
This is resolved with Cold Dark Matter.
This is a glurge about the work of Halton Arp and other observational astronomers who think that they can determine whether things are connected simply by looking at them. The sky is an interesting phenomenon: we can see in only two dimensions, the third needs to be arrived at through other means. It turns out that Halton Arp thinks distant quasars and galaxies are connected. They are almost certainly not, but people don’t like to be told that their inferences from what they see are incorrect. Arp persists, but he’s getting old and frankly that stuff isn’t taken so seriously.
If you actually test the idea that quasars are associated with nearby galaxies using statistics you find that it is not held up by systematic survey observations. Anybody can go “treasure hunting” and find weird coincidences (the sky is a big place). It happens that Arp enjoys doing this, but his findings are simply peculiarities and not indicative of problems.
I explained how this problem is resolved above. It just happens that our universe is clumpy because of dark matter.
That’s why you need dark matter that’s cold and collisionless.
Superclusters are well-modeled. We understand how these things form. And since we now have the “end of greatness”, it looks to me like we’re pretty much on the right track.
This has been recalibrated and found to be an incorrect measurement.
As I said before, the error bars on these dates extend well down into the age of the universe as observed by WMAP. There is no “quasar dating” that was placed at 16 billion years old that I’m aware of.
I hope this resolves some of the “issues” which really were more of “outstanding problems”.
We are entering an era of precision cosmology where the question isn’t so much “what caused this contradiction”? As much as “what are the details of the way things set up”? Or universe is weird, as I outlined above, but it’s home.
Woops! Yes, I agree, I didn’t know the nature of the publication. However, the short summary I referred to corresponds with those questions raised by scientists.
The biggest problem I have with the BB theory is that it seems we humans are determined to belive that everything has to have an beginning and an end. The BB theory fits right into this: There was a gigantic explosion which created the universe, and then we got planets, stars and galaxies. But if all the matter in the universe was once in on place, where did it come from (energy cannot be created out of nothing) and why did it “conjugate”? And why did it explode?
The problem with inflation and dark matter is, as I understand it, that it is a flawed theory introduced to explain another flawed theory. It might be true, and I could be entirely wrong, but from the link above:
*"A major problem developed with inflation: inflation predicted that the rapid expansion would have occurred in a number of separate spatial bubbles which should be observable today. Bubbles were a major problem for inflation because they are not observable.
Notwithstanding the bubble wall problem, the cosmology world was galvanized by the novel concept of inflation since it solved such difficult problems. One possible solution to the bubble problem was worked out which predicted that the observable universe would occupy but one billion-trillionth of a single bubble domain. This theory eliminated bubble walls as a major worry: the walls would be so far beyond our observational reach of about 15 billion light-years that they could never possibly become visible.
…
Another major problem with inflation is that it required that omega (W) equal 1 exactly and thus required the universe’s mass to be 10 times the amount we can account for. To solve this problem, theorists, adopting inflation to cure observational problems with the Big Bang, proposed that 90% of the mass of the universe was missing; they proposed a “missing mass” to represent 90% of the universe. They called this missing mass “cold dark matter,” which also has never been observed. Moreover, the cold dark matter was required by the theory to consist of non-baryonic material, unlike any of the matter in the rest of the universe."*
In other words, inflation and dark matter is based on something that cannot be observed nor accurately measured (at least not yet). It’s like introducing a theory saying apples taste great because of an unknown element that nobody can see, feel or prove is there. It goes against anything science is about.
I disagree. Recent images of spiral galaxies with different redshifts, does indicate that these objects are part of the same galaxy. Undoubtly, there are instances of images were this is caused by overlapping, but there seems to be plenty of examples of the opposite. However, I would need some help or time to dig to identify such galaxies by name.
I have no objection to the rest of your points, I’m still learning.
On preview I notice JS Princeton has posted a lengthy post.
Please explain their flaws. Dark matter is observed as is inflation. As to the details: yet they are left to be looked out.
No, “entirely” wrong discounts the observational fact of inflation and dark matter.
No, the “bubble” problem is actually resolved by the horizon problem. It happens that inflation occurs everywhere, but an individual bubble becomes too large for you to see outside it: you spend the rest of your existence inside ONE inflationary bubble. Therefore there is no discrepancy at all.
In part, but it was also “galvanized” because inflation was general: that it seemed no matter how you started you were BOUND to get inflation. In fact it is very difficult to come up with a theoretical model that doesn’t end up in an inflationary epoch.
This is exactly right: especially because we know that inflation has to produce anisotropies on the order of 10^-5 (as observed from the CMBR). If you work back to what kind of scales are needed for a quantum fluctuation to grow to a supercluster it gives bubble walls which are so far away from our horizon limit as to be utterly and totally unimportant to the present universe.
Actually it’s the other way around. Omega was required to be one because we observed an isotropic CMB as well as minimal observed curvature. That’s the so-called “flatness” problem. Inflation is a RESOLUTION to the flatness problem and as such to claim that a problem is that it requires Omega to be 1 is ludicrous. That’s the whole point of inflation!
This last point is an absolute lie. Cold Dark Matter is observed in our own galaxy as well as everywhere we look in the universe. Dark Matter wasn’t proposed simply because of inflation: we had EVIDENCE that dark matter existed well before this. People knew about Dark Matter well before the CMB was even discovered!
Why is this a problem? Explain.
Wrong on both accounts: dark matter is observed AND measured. See above.
It would if that was the only evidence we have for dark matter: but the fact remains that we see dark matter in the universe by means of its gravitational effects.
I disagree. Recent images of spiral galaxies with different redshifts, does indicate that these objects are part of the same galaxy. Undoubtly, there are instances of images were this is caused by overlapping, but there seems to be plenty of examples of the opposite. However, I would need some help or time to dig to identify such galaxies by name.
I have no objection to the rest of your points, I’m still learning.
On preview I notice JS Princeton has posted a lengthy post.
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