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It's Official: You're Lost In a Directionless Universe (sciencemag.org)
Reader sciencehabit writes: Ever peer into the night sky and wonder whether space is really the same in all directions or if the cosmos might be whirling about like a vast top? Now, one team of cosmologists has used the oldest radiation there is, the afterglow of the big bang, or the cosmic microwave background (CMB), to show that the universe is 'isotropic,' or the same no matter which way you look: There is no spin axis or any other special direction in space. In fact, they estimate that there is only a one-in-121,000 chance of a preferred direction -- the best evidence yet for an isotropic universe. That finding should provide some comfort for cosmologists, whose standard model of the evolution of the universe rests on an assumption of such uniformity.
I guess my purpose is to lead a meaningless, directionless life.
120 characters ought to be enough for anyone
...God is everywhere. Well at least there is a 1 in 121,000 chance He is. That is good enough for me!
What happened to the CMB Dipole? Did it vanish?
Neither "lost" nor seeing how the topology of the universe is pertinent in any sense to that.
Rather a long stretch from the science to a populist click-bait philosophical "conclusion"...
~ Whence do you come, slayer of men, or where are you going, conqueror of space?
This is what happens when you use Apple Maps for directions...
So, does this mean there is no Axis of Evil in the CMB radiation?
This seemed to be a thorny problem that wasn't going away as per many expert opinions not long ago, but now everything's fine again?
What if the observable universe (whose boundary is the CMB or maybe the cosmic neutrino background) is only a small tiny fraction of the actual universe, and it does have a direction, but that direction is so small on our scale that it isn't measureable and lost in the noise?
The final frontier.
This doesn't convince me that the universe isn't just a bunch of left over particulates from the power stroke of an ICE. A few hundred billion more years and we're probably going to start getting pushed out the exhaust valve.
When physicists talk about the universe, they usually talk about the observable universe, and we are right in the center of it, even more so now that we know it is directionless.
You are in a universe full of twisty little galaxies, all alike.
Mod me down with all of your hatred and your journey towards the dark side will be complete!
One in a million chances come up nine times out of ten.
I know exactly where we are alright? The Phanerozoic Eon was just the first agnathan fishes, then after we did that I made a left turn near the Earliest salamanders, newts, cryptoclidids, elasmosaurid plesiosaurs, and cladotherian mammals...I stopped once to ask homo habilis for directions and the key to the bathroom but ill be damned if we stop again for homo sapiens to turn us back around another direction when weve got the muon detectors telling us the universe is infinitely expanding. Anatomically modern man my ass, that thing worships the higgs boson and launches garbage into its planetary orbit.
Good people go to bed earlier.
Wouldn't this discount the possibility of a (multi-)toroidal-shaped universe?
Never tell me the odds.
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
We're as lost as a biddy in tall grass.
Feel free to add your own . . .
2 directions. Inwards and outwards.
Hey, you're not lost. Look on the bright side. You're always at the center of the universe. ;^)
If there were two counter-rotating ring-style space stations, but there was no other matter/energy anywhere else in the universe, would there be any way (assuming you have no knowledge of the past) of telling which was rotating and which was not, or whether both were to some degree?
Where are we going and why are we in a handbasket?
The Big Bang wasn't an explosion. There was no center because all space began expanding.
The world's burning. Moped Jesus spotted on I50. Details at 11.
...isn't this obvious?
I thought it was clear that the further you look, you're ultimately looking back in time.
Look far enough, and you could see the beginning point of the universe, no matter which direction you look.
Carl Sagan seemed pretty clear about that in the science shows of the 1970s.
-Styopa
You sound way too rational to be an AC here at Slashdot.
Have you considered signing up for an account? Or, alternatively, commenting on sites that are much more serious than this one? Reading your post, I have the feeling your rational thoughts are going to waste here. You might actually help people think if you keep doing posting well reasoned statements here.
While the CMB may be without spin, there are giant voids that appear to only exist in one direction. Saying "the universe is isotopic" implies that it's the same in all directions, and if there are giant voids in only one direction, then that's clearly false.
Now to state that the CMB is without direction inherent in it may well be a true statement, and it sounds much closer to what they actually showed. That, itself, is an interesting statement, and may well be true. The step from there to "the universe is without direction" appears false. Which is an interesting result, and may be significant. Somehow if cosmic inflation happened it allowed minor variations to be expanded into significant variations. (This has been proposed before as one of the reasons for believing in inflation.) But this would appear to imply that the CMB was set at a time before inflation. (I don't know whether this is standard theory or a new result.)
I think we've pushed this "anyone can grow up to be president" thing too far.
No. Yes. Do google when you are more alert, if you are to tired to search you are probably to tired to understand the explanation. :)
Hint: The Big Bang created everything, it didn't distribute material in an existing space.
They have measured x - and x show no indication of a preferred direction.
They also have estimated that with the error marginals of x, with the known factors that can influence it there is a 1:121000 chance the measurement is sufficiently wrong that there may be a preferred direction after all.
Pretty simple really.
According to Kurt Gödel, a rotating universe allows for time travel. Not sure if a directionless universe implies non-rotating, but I'd think so (otherwise the axis of rotation would be a privileged direction). So history is stuck with Hitler. Also no way to have a sex change and go fuck yourself.
Non-Linux Penguins ?
That the Earth "hangs upon nothing", and now we have rehabilitation of geocentrism (in the sense that the reference frame is arbitary, but then that's been established since Einstein)...
To name two.
I'm guessing that the above are being attributed to those in ancient times who actually dared to think for themselves and question what their elders decreed, and it does not include the "Earth is unmovable on its foundation" crowd?
This space unintentionally left blank.
So the mainstream cosmologists' viewpoint is based on the assumption of isotropy, and this result shows support for that. But what assumptions does this result rely upon, and what do you do with the 'intellectual ponzi scheme' problem of needing to rely on progressively more and more, deeper and deeper assumptions to back up your reasoning?
(I did my doctoral studies in the foundations of mathematics, and take a perverse interest in such intellectually subterranean stuff.)
John_Chalisque
The earth is at the center of the universe - the origin, the point of the original Big Bang! That would explain the universe expanding out in all directions from here...
Are you so tired that you don't know the different usage of "to" and "too"?
"Eve of Destruction", it's not just for old hippies anymore...
Hmmm, how do you determine the direction of the universe of where a void is?
To my understanding, voids appear to correlate with the observed temperature of the CMB because of the Sachs–Wolfe effect. Colder regions correlate with voids and hotter regions correlate with filaments because of gravitational redshifting. What if galaxies and matter follow a gravitational path much like a meandering river follows the easiest path (in this case, the warmer path of sorts)? I'm no cosmologist or astrophysicist, just a curious mind.
Tired of my customary (Score:1)
No. But too tired to not making input errors - while I'm not too (!) bad at the keyboard I don't use normal touch-typing and so typing errors sneak in from time to (!) time. In most cases I try to catch them before posting however you found an example post where I didn't .
--
Why did you bother making such an idiotic post? Does it make you feel powerful in some way? Are you the AC I replied to and felt insulted by my post causing this immature kind of retaliation? The intention of my post was to state my opinion and provide some hint, nothing more - nothing less.. Searching for good explanations is a better way to actually begin to understand this complex topic IF one actually want to try to.
If you are just a common asshole then please FUAD
Not that there can't be both, what with one point not being enough to establish a coordinate system, but it's a good starting point for an otherwise arbitrary system.
"Based on what we currently think about inflation, this means that the Universe is at least 10^(30) times the size of our observable Universe! "
http://scienceblogs.com/starts...
I remember the number being 10^28, but these are just guesses... but still, that puts the relative size of the "actual" and observable universe at almost the relative size between YOU and a PLANCK LENGTH. (well, 10^35, but close!)
I've got a bad attitude and karma to burn. Go ahead. Mod me down.
You look. In the directions where you don't see stars, you say there's a void. (It's a bit more complicated, but that's the general approach.)
I think we've pushed this "anyone can grow up to be president" thing too far.
I RTF-Abstract a couple of days ago, but decided against submitting it as bing probably a bit too esoteric for Slashdot. But most of the questions I've seen posted up-thread are covered in the actual paper - at least to the level that I can handle cosmology, which is not very deep.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
What does this mean for Big Bang and Steady State?
There is an obvious direction. We call it "time".
Does it really matter - practicality-wise?
My guess is that we will all be looooong gone before we get -- there?!
Self-importance and self-indulgence is the root of ALL evil.