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Stars Could Shine In Many Universes
A commonplace of cosmologists who argue the anthropic principle is the assumption that if any or a few of the constants of nature took on an even slightly different value, life could not have evolved — perhaps even stars and galaxies would not form. Science News reports on a new calculation showing that, to the contrary, star formation could happen in up to one-quarter of universes with different values of three important constants. "In fact, all universes can support the existence of stars, provided that the definition of star is interpreted broadly," said the researcher, Fred Adams. "...calculations suggest that, contrary to some previous claims, stars are not only common in our cosmos but are also ablaze in myriad other universes, where the laws of physics may be drastically different... Had Adams found that the range of parameters that allowed for stars was very small, that would have suggested that the laws of physics in our universe have been 'fine-tuned' to allow for star formation... Instead, Adams' study shows that our universe doesn't seem particularly special in that regard."
I dont read slashdot for 2 days and I missed the fact that there are more than 1 universes... shit!
This hypothesis, if true, shows that the universe is actually a rather robust structure.
I like that a lot more then the 'one tiny bit off and you get nothing' thing. It sounds more plausible to me.
A learning experience is one of those things that say, 'You know that thing you just did? Don't do that.' - D. Adams
Even if we are rare, why does that make is so special? It's rare to win the lottery, but it's got to happen to someone doesn't it? If we hadn't won the lottery, we wouldn't be here to talk about it, would we?
A-Bomb
I can't wait to meet the evil me and see how I look with a pointy beard.
I'm sorry, but it's the "mathematical phantasy" thing.
Or more correctly: It's a tought experiment, to find out if the universe has some special fine-tuned constants, because this would pose some interesting questions on why they are exactly like this.
Of course, as far as our knowledge goes, the universe could be a 4d sphere (with a 3d surface). So there is still the question "is there an 'outside' to the universe"? If so, what is there? Other universes?
A completely different, and more realistic POV is to see our universe as the cone or our event horizon. So there could be space outside that we'll never see, but that is perfectly normal "space". Of course this would pose the question, that if the constants are different in "another universe" (= another place outside our event horizon), then why is there no visible gradient when you get near the border of that horizon?
Any sufficiently advanced intelligence is indistinguishable from stupidity.
Oh stop it. In a parallel universe, this makes perfect sense.
No folly is more costly than the folly of intolerant idealism. - Winston Churchill
I think you mean to say anything outside the light-cone of the big bang is a different universe.
That is fairly defensible, I'd go with it.
"A universe without weak interactions is constructed that undergoes big-bang nucleosynthesis, matter domination, structure formation, and star formation. The stars in this universe are able to burn for billions of years, synthesize elements up to iron, and undergo supernova explosions, dispersing heavy elements into the interstellar medium.
There's no evidence such universes exist. But it is still a good exercise to help keep some perspective on what is possible, even in principle, given what we know about physical law. It also highlights that people who make "anthropic principle-like" claims based on fine-tuning haven't bothered to go back to the underlying laws of physics and actually look for other stable configurations, even in theory.
i\hbar\dot{\psi}=\hat{H}\psi
I continue to be bothered by the use of the word "universe" to mean something other than "everything". Having to substitute "multiverse" to replace the word that didn't need to be replaced (rather a new word should have been invented for the new concept) bugs the crap out of me so much so that I hope all these new theories are proved wrong so we can maintain continuity of the language.
i thought "uni" meant one and only.
doesn't "uni" mean one and only?
Which is why I find your double post so delightfully ironic!
Well, back to rejecting software patent applications.
Proponents of the Anthropic Principle do not claim that universes which cannot support life are rare, or commonplace, or anything of the sort.
The Anthropic Principle merely says that we should not be surprised to find the universe conductive to our existence, even if such conditions are highly improbable, because the fact of our existence logically necessitates that we exist in a universe conductive to it.
-Forrest Cameranesi, Geek of all Trades
"I am Sam. Sam I am. I do not like trolls, flames, or spam."
This research is great because it points out that the constants and such that the universe exhibits aren't so special, however the way it's presented is quite ridiculous.
Firstly, these "universes" are purely theoretical, and they're function of the modification of a few constants, that doesn't mean they're actually out there.
Secondly, I just hate it when people say "myriads/an infinity of other universes". What you really mean by "infinity" in that case is not a large number of discrete universes, but continuous variations of a universe. Presenting something continuous as an infinite amount of discrete things is stupid and misleading, although somehow correct. Sure you can iterate some constant by the smallest increments you want, so you can cut the whole thing into an infinity of possibilities, but just because you're sampling something continuous discretely doesn't make it cease from being continuous and not discrete. That's exactly like saying the 3D space universe is actually made of an infinity of stacked up 2D universes that communicate between each other. A completely arbitrary way to look at things that misleads you on the real nature of things.
You just got troll'd!
This hypothesis, if true...
The Standard Model has 19 free parameters (not including G) and even more if you include the new neutrino mixing results. This guy varies TWO of them plus G and then claims that 25% of possible universes would form stars? I remain completely unconvinced. While the strength of gravity, EM and the strong interactions may be important for stars the other parameters control some other vaguely important things like whether there is any matter in the universe.
In addition these parameters also have major effects directly on the functioning of stars. For example if the electron mass were larger the orbit of the electron in the atom shrinks and fusion becomes a lot easier. One would presume that this would greatly affect star formation. In addition there are other effects caused by varying the parameters: tweaking with these may well change the type of matter in the universe such as less hydrogen and more helium etc. He does at one point mention this and then states that he would not expect it to vary much from our universe without giving a reference. To me this seems completely non-obvious but I'm not a cosmologist so perhaps it is obvious to them?
So as I said I remain totally unconvinced that this paper really shows anything meaningful at all.
As I said above, I think the multiverse theories are a pantload of stink.
The interesting thing about a way of describing the universe is that it doesn't have to be true to be userful, provided it produces useful results.
Think for a moment of Copernicus.
His model wasn't accurate at all, not even slightly, it was nowhere near as useful in real terms then the Ptolemaic model, but it allowed the universe to be viewed in a different way, eventually leading to our current, vastly more accurate description.
Ours too may be wrong, but you need ways of describing reality which produce useful results. They don't have to be 'real' to be useful.
A learning experience is one of those things that say, 'You know that thing you just did? Don't do that.' - D. Adams
Considering Paris Hilton is famous for being basically nothing more than a rich party girl, and given the popularity of Youtube these days, I bet even a feces throwing monkey could become a star in OUR universe.
WWJD.... for a Klondike bar?
Would you all screw off about Popper. No one has ever done science the way Popper said they do, and even he backed off on is ridiculous claims in later years.
The world's burning. Moped Jesus spotted on I50. Details at 11.
I didn't know that astrologers used telescopes.
At the visitor information station on Mauna Kea, I am routinely approached by followers of astronomy (henceforth "gullibles") during the evening stargazing sessions. It usually goes something like this:
Gullible: It's my birthday, can you point out my sign?
Me: (points at the ground)
Anyone who subscribes to pseudoscientific nonsense but doesn't even read enough of it to know that their sign is the one the Sun is in when they're born, should be duct-taped in place and forced to listen to Weird Al's "Your Horoscope for Today."
To their credit, no Christians have asked me to point out the star from when Jesus was born. Yet.
Village idiot in some extremely smart villages.
Other religious writings place their god as part of or within this physical time-space-matter-energy universe.
I'll post this yet again, because this wrong assertion just keeps getting made:
No. You obviously lack the familiarity you claim to have with other religions, even very closely related ones, and with religion in general. Islam and Judaism make this same claim, and even about roughly the same God! Hinduism and Daoism have very different spins on this idea. Zoroastrianism has exactly the same theological concept (Ahura Mazda, the uncreated creator) that you just claimed was true only of Christianity. Only one of the few, major counterexamples I just gave is younger than Christianity, and most are *much* older. It is either naive or arrogant of you to think that your religion (in this case, Christianity) is the lone bastion in all human history of people being in some way "reasonable" about their religion, above and beyond how poor that reason actually is.
The record tells us that those who came to arrest Jesus fell down backwards at the sound of the name of God.
"The" record? There are many books, and many holy books, but they do not constitute historical "record". The Bible claims a lot of unlikely events happened. So does the Koran, so do the Vedas, and so does the New York Times. Not every claim that gets made or reported is true.
The Bible tells us that God just is.
But it is just as easy for the universe itself "just to exist". Religious claims of special creation don't solve any mystery at all, and they are worse because they require belief without evidence.