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Study Hints At Time Before Big Bang
canadian_right informs us that scientists from Caltech have found hints of a time before the Big Bang while studying the cosmic microwave background. Not only does the study hint at something pre-existing our universe, the researchers also postulate that everything we see was created as a bubble pinched off from a previously existing universe. This conjecture turns out to shed light on the mystery of the arrow of time. Quoting the BBC's account: "Their model suggests that new universes could be created spontaneously from apparently empty space. From inside the parent universe, the event would be surprisingly unspectacular. Describing the team's work at a meeting of the American Astronomical Society (AAS) in St Louis, Missouri, co-author Professor Sean Carroll explained that 'a universe could form inside this room and we'd never know.'"
new universe.
Their they're doing there hair.
Didn't string theory already predict something like this?
Really though, what (in the background radiation) would point to no time before the big bang? A Kotch curve? A Hilbert curve? Complete order and continuity? I fail to see how 'blips' in the cosmic background radiation proves anything about time before the big bang.
that once we fully understand the universe it will be replaced with something even more complicated.
Others argue that this has already happened...
thhgttg
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Alan Guth described this sort of thing, and many other possible origins of the universe, in his book written in 1998. I think I even remember him hypothesizing that a universe could possibly be its own parent. Definitely old news.
Seriously, I read about this idea years ago in Alan Guth's book, The Inflationary Universe. Chapter Fifteen.
When I first read this, it sounded so strange that I was unable to conceive it in any meaningful way. Then I got really high. Now it seems self-evident. It may not be genuinely insightful, but it sure is fun.
Property is theft.
By the way, just to avoid confusion, what I meant by the above is this: consider an experiment where you are blowing up a balloon and you measure time by something traveling in the balloon or by the rate that the balloon expands. How do you measure time before you started inflating the balloon (where it had a volume of zero) when your experiment can only be done inside the balloon? It only makes sense to define time as far as the balloon (or universe) is concerned after the inflation has begun and the volume enclosed by the balloon is greater than zero. There is no you can infer by any characteristic in the balloon how time worked before. From an abstract reference point, this could be the first time the balloon inflated, or maybe you pinched off a zero volume part of another balloon and started inflating, or maybe this balloon inflated from zero and then deflated to zero over many cycles. Your measure of time has no meaning in any case and none of them are related. The expansion could have been different or you could have used a different gas which would affect each potential measure of time in the balloon.
...String hypothesis.
Sounds like you are insane in the membrane.
AFAIK, it didn't predict anything (experimentally measurable) yet that isn't already predicted by other, simpler theories. I.e., it still fails Occam's Razor. Miserably.
Plus, AFAIK a lot of it has a lot of possible solutions, and for some they don't even have the equations (yet), so there's not much of a prediction you can do with it. So far the majority of it isn't even as much a theory, as in something where you plug your values in a clear formula and get a prediction, but more of a theory that a theory might exist.
Or to put it otherwise, it's more of a mathematical construct than physics. Don't get me wrong, maths is a very very useful tool. Essential, even. But if I'm allowed a bad analogy, it's a bit like a painter's brush: it can be used to paint anything, regardless of whether it's real or outright impossible in the real world. You can use it to paint Mona Lisa or Escher's impossible pictures. So is maths. You can describe an infinity of possible universes with it, most of which have nothing to do with ours. You can use it to describe light propagation through ether, or the raisin pie atom model, or the ancient geocentric model, or even the counter-Earth ideas from waay back, all of which by now we know to be false. It becomes physics (or generally science) when you can test that formula against the real universe and see if it fits or not.
A polar bear is a cartesian bear after a coordinate transform.
i don't see why the universe can't be endless in time and space, and the expansion and contraction we see is local, while somewhere else they are having a pinch. kind of like the choppy surface of the ocean on a windy day: troughs and peaks
once we thought the earth was the center of the universe. we threw that centrism out the window. can't people see that the big bang theory is the same kind of centrism?: "this is all we know, therefore, that's all there is"
if there is anything science teaches us, it is that we are not the center of everything
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
What we are doing is conjecturing. We know there is no experimental way to find out about meta-universes a posteriori, so we theorize a priori. One of my favorite a priori meta-universes that is completely consistent with our own universe is a computer simulation. In the same way that a computer on Earth can simulate the Universe in the game Pong without the physical laws being even remotely similar, our Universe could be simulated with the physical laws different from the simulator. That is, of course, if a simulator exists, which I don't know nor do I think we can ever know (unless the programmers put in Matrix-like quirks).
I like the Pong example because you have a definite way to measure time (via position and velocity in the game, where velocity is the position increment per for loop). You can even pause the game in our Universe and it won't affect the time measurement in the game. If you paused the game for 1 second, let it continue for 5 s, and the paused it for 10 years, and then let it continue, the in game time would only be due to the position and velocity of the ball in the game. This is a great illustration of how even time isn't connected in the Pong Universe and our own.
Why do we think that our concept of time in our balloon-like universe necessarily has to be the same as that of some conjectured universe that we might have come from?
More like :
Universe newUniverse = new Universe(oldUniverse);
Slipping shoelaces ?
1. Engage in baseless conjecture about alternative, unproveable universes.
2. Define new branch of mathematics that can support a complex multi-dimensional model reinforcing your baseless conjecture.
3. Publish in academic journals and popular media.
4. Lecture to gullible masses.
5. Profit!
6. Avoid performing any work beneficial to mankind. ~
Invenio via vel creo
Although the word "nazi" is now accepted to mean "a person who is fanatically dedicated to, or seeks to control, some activity, practice, etc." this is etymologically inaccurate. Outside of playful uses (such as "grammar nazi" or a TV serial's "soup nazi") the word "nazi" should be synonymous with "a member of the National Socialist German Workers Party," and we ought to come up with some intermediary term (like "asshole" if you feel like you require a more abusive term) to refer to this kind of pedantic overbearing we've found ourselves saddled with.
Word definitions and connotations have a tendency to move around quite a bit. The word "stink" for example, was once a neutral term to describe something giving off a scent, and now has decidedly negative connotation, if not being outright denotative of giving off a bad odor. Similarly, nazi once meant the members of the political party that established a murderous and expansionist totalitarian regime in Germany. Now it used to describe someone who likes to pick on people's misuse of its vs. it's.
The article the slashdot summary links to is basically a drastically shortened version of this recent article in Scientific American, plus a nutshell presentation of this paper.
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Indeed, but that's not what Occam's Razor is about. You may predict or explain any event or thing, no matter how complicated. Occam's Razor is only about _how_ you explain it.
Basically, imagine that you walk through an apple orchard on a windy day, and an apple falls on your head. Let's pick two possible explanations:
1. Probably the wind shook a branch and an apple fell.
2. The Illuminati hired a secret Ninja clan from Japan, to follow you around and drop an apple on your head when a good opportunity presents itself. And they picked a windy day so the rustle of leaves would hide their noises.
Basically Occam's Razor just says that if explanation #1 explains it well enough, go with explanation #1. There is no need to complicate it with unneeded extra elements.
Incidentally, from a science point of view, #1 also has _some_ predictive power. You can, for example, calculate what the probability is to get hit by an apple, or in what season it's more likely, or whether you need to wear a hard hat or it'll likely be just a minor bruise. Explanation #2 is pretty worthless, since there's no way to predict who the Illuminati want to drop an apple on and on what date. You don't even know whether to wear a hard hat, since they might drop an apple made of lead if they want to. (Ninjas can do stuff like that;)
On the other hand, if explanation #1 doesn't explain it, _then_ you can look for a more complex explanation. E.g., if you were walking through a banana plantation and an apple fell on your head, maybe it wasn't the wind after all.
But again, this all has to do with the explanation, not with the thing you explain or predict.
A polar bear is a cartesian bear after a coordinate transform.