Slashdot Mirror
Doughnut-Shaped Universe Back In the Race
SpaceAdmiral writes "The once-popular idea that the universe could be small and finite is making a comeback. Many researchers thought that a 'wraparound' universe would mean that distant objects would be seen multiple times in the sky, but new research suggests that a '3-torus' (or 'doughnut universe'), as well as other shapes, could fit our actual observations, particularly the WMAP data."
Though it's possible, how many other things in the universe are naturally doughnut shaped?
"Your theory of a donut-shaped universe is intriguing, Homer. I may have to steal it."
God spoke to me.
I guess it depends on your perspective. It looks like a goatse universe to me!
mmm ... donut universe <drool>
Ob: Simpsons
More music, fewer hits
I'd love to read it, but... what's with all these pay-to-read links lately?
$8 for an article? Most magazines cost less.
I have not lost my mind... it's backed up on disk somewhere!
"...new research suggests that a '3-torus' (or 'doughnut universe'), as well as other shapes, could fit our actual observations..."
Great...it all ends when we wind up being eaten by some fat-ass cop from the other side of a black hole.
I've calculated my velocity with such exquisite precision that I have no idea where I am.
Right in the very middle.
So what's the point in running this if we have to pay to RTFA? Supposedly anyone already paying is likely to read it anyway, so the only ones this posting is for is for those who do not already subscribe to the site. In a world where information wants to be free, I hardly see it as appropriate for Slashdot to hype up a pay site. Were there no interesting articles on any free sites today? Or did Slashdot get a payment for posting this advertisement for this pay site? Did paid subscribers to /. also see this ad sneakily disguised as an article (if so I bet they resent it even more than I do).
I'm an American. I love this country and the freedoms that we used to have.
TUBULAR!
Previously: "Linux... Toward the Sunrise..." Now: "Linux... Toward the-- No, now, part of Every Sunrise"
Apparently we'd all be much happier of we had our minimum of 17.3 glazed per day!
http://www.sfgate.com/cgi-bin/article.cgi?file=/comics/Zippy_the_Pinhead_Color.dtl
-WtC
Creator of RPerl, Scouter, Juggler, Mormon, Perl Monger, Serial Entrepreneur, Aspiring Astrophysicist, Community Organiz
Mmm, doughnuts...
Now cue new prophets going on about the impending arrival of the Great Homer, whereupon our entire universe will be rendered into bite-size chunks and slowly masticated into elementary particles of deep-fried pastry goodness.
Cheers,
"What in the name of Fats Waller is that?"
"A four-foot prune."
I have some questions for the cosmologists among us.
When talking about a closed (positive curvature) geometry like the one described here physicists say that the universe will have enough mass to eventually stop expanding and then begin to collapse on itself. However, when I imagine a 2D version of this I see a circle expanding on a sphere (or donut) until it wraps around, at which point the mass will recollect on the opposite side. In that model, the universe isn't so much stopping expansion, but continuing it until the universe turns inside out and the edges of the (matter within the) universe become the center, and the center becomes edges. Is this is how it would occur, or would the current edges remain edges, and it would just stop expanding and start collapsing?
Or is the idea of an edge just not valid? In my example the universe only took up a partial amount of the geometry, and then expanded and moved within it. Is it instead the case that the universe has occupied the entire geometry from the very beginning, and the donut itself is expanding, and will latter collapse? (umm raisin bunt cake)
All the discussions of universal geometry are explained as depending on the mass of the universe bending it as per General Relativity. Wouldn't that then mean that we don't have a static geometry, but one that is changing as the universe expands?
And how does time fit into all this - when the geometry wraps around, is it only the spacial dimensions that wrap around and time still extends to infinity in both directions, or is time also closed? (Thinking about that hurts my brain).
The problem with curvature is that it imples continuity (infinite divisibility), which leads to an infinite regress. Therefore curvature is an unacceptable concept in physics. That continuity should continue to be used by physicists as a fait accompli is sad commentary on the status and credibility of the physics establishment. It's time to abandon the Star-Trek physics and move on.
I think it is completely reasonable for slashdot to assume a base level of resources available to its user base. In this case, the presumed user base is everyone who knows ANYBODY attending ANY college. Pretty much every university provides off-site journal access to their students (whether the students know about the service or not). I think that covers most everyone here.
Additionally, when a college subscribes to journals, it usually subscribes to hundreds or thousands. It seems a bit naive to say:
How are the sure it's a donut and not a bagel?
FWIW, here's the preprint.
Haha, I can't believe this kooky bullshit got modded up. Note to mods: the link is to a crackpot site where the author, who is not a physicist or a mathematician, provides "proofs" showing Einstein was wrong, modern physics is wrong, etc.
I think that covers most everyone here.
Not even close. I for example am post college, as probably a large percentage of /. readers are, and it annoys me no end when college subscriptions are assumed. Not to mention being equated with "free" when they're not.
That site may indeed be kooky, but I was recently reading an article in a science mag indicating that this idea may be true. It might have been in an article about time at SciAm.com, not positive though.
My point must not have been made clearly enough in my post. I am six years out of college myself, and I'm fortunate enough that my institution provides access to journal subscriptions. However, if I had no other way to obtain access to the literature, I could easily ask any number of college students or recent graduates that I work with who still have subscription privileges. I find it hard to believe that a significant portion of the /. readership is not on friendly terms with a recent college graduate through work or otherwise.
That was written in 1896, putting it 12 years after Flatland which I think was the first treatment of the theme of the consequences of differing numbers of dimensions. Nothing new under the sun, eh?
- None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
Yeah, because 100% of nerds (the target audience of slashdot) are in college. I like how your moronic prejudice rules out anyone who is a) still in high school b) out of college It's not like it's unusual to be so long out of college that one's entire peer group is also out of college. In fact, this typically happens with a few years of graduating. Which leaves an entire decade of nerd-life before one would have free access to journals, and five or six decades of nerd-life after the period in which one would have free access to journals. Are you really so enormously stupid that you believe that all Slashdot readers are in college or have just recently graduated? Or are hanging out with college students right now when they want to read the article? I hate to toss around insults, but that's really some circus-grade idiocy. I mean, WOW.
Haha, I can't believe this kooky bullshit got modded up. Note to mods: the link is to a crackpot site where the author, who is not a physicist or a mathematician, provides "proofs" showing Einstein was wrong, modern physics is wrong, etc.
And what if they are? The last I heard, neither Einstein nor modern physics is infallible. What's with the chicken shit personality cult, eh? Besides, there is nothing like a little ad hominem to cast doubt on an argument in the minds of idiots. The fact is that continuity does lead to an infinite regress, something that even children can grasp. So why does the physics community insist on perpetuating this crackpottery? The only reason that I can think of is psychological and political. It is easier to kiss ass and safeguard one's career than it is to bravely step up to plate and tell the emperor that he's buck naked and stupid.
Don't mistake the map for the territory.
More than a decade has passed since I was in school and I live in the sticks; so no, I don't know _any_ current students or recent graduates.
Additionally _every_ slashdot reader I know in person, all five of them, are either in the same position as myself, or are pre-collegiate children.
If I was _really_ interested I could pay the eight bucks, or find some student online to give me a proxy or something. I'm not however, but your post annoys me.
Not everyone here fits in your little world, sorry.
I find it hard to believe that you think that the fact that an article is accessible by someone I know makes it accessible to me.
In the context of the World Wide Web, something is accessible if and only if it shows up in my browser.
And no, I don't know any recent college graduates, at least not on terms where I would comfortablely bug them to go download an article for me.
Tom Swiss | the infamous tms | my blog
You cannot wash away blood with blood
You're a glass half empty kinda guy aren't you? I see this as an opportunity to have a legitimate excuse not to RTFA. I'm a cheap bastard.
These posts express my own personal views, not those of my employer
I'm a "some fool used the wrong glass" kinda guy.
I'm an American. I love this country and the freedoms that we used to have.
Comment removed based on user account deletion
Without a doubt, all our current models are "wrong" in the sense that they are not perfect. However, they are less imperfect than their ancestors. Science is iterative, and only a philosopher claims to find "absolute truth."
It's insulting to humanity to fail to recognize the amazing accomplishments of the present theories. Not every chap can dream up something that predicts reality so accurately as Einsteinian relativity.
I have some faint recollection from the early 90's that, during WW I or II (or both?), their was some research into the building of a telescope powerful enough that, when pointed straight up, would look right out the 'end' of the universe and in the other in order to spy directly on the exact opposite side of the planet. Now, to search for any links to back that strange memory up...
Leela: "Is all the work done by children?" Alien: "No, not the whipping."
1) Many scientist recognize open access is the right way to do science.
2) Open access journals tend to have higher impact factors. The impact factor is a measure of how important the journal is, and is mostly measured from number of citations from the journal. Open access journals gets more citations, because they are easier to find with a web search.
3) Many funding agencies have started requiring articles to be published in open access journals. Recently, the Danish equivalent to the NSF did that. (Moreover, I don't think the screen they provide is particularly useful - in fact, I think it's even harmful because it imposes a socially constructed restriction on one's exposure to new ideas - but that's just my own opinion). If you knew how much crap was submitted, you'd value the screening. In the case of Nature, I think most people pay to have their work in it because of the prestige of having an article published in Nature rather than the journal's audience. If they just wanted others to read it, they could find other journals to accomplish this goal. Yes, an article in Nature can basically secure your position in a University. The whole thing is a pretty nasty scheme: the authors sometimes pay, the readers always pay, and the reviewers don't cost anything, so where is the money going? Editors. It is true that the scientific part is done by unpaid reviewers, but the part of being unpaid is that the reviewing get low priority. Which leaves lots of work for the editor. The more prestigious, the more work. You can look at the prices for submitting at PLoS, a non-profit open access publisher, to get an idea of the cost associated.
Remember a cruller is a donut too. Does this mean that parallel universes may be donut holes?
Invenio via vel creo
Doughnut-shaped Universe bites back
Astronomers say Universe is small and finite.
Zeeya Merali
The doughnut is making a comeback - at least as a possible shape for our Universe.
The idea that the universe is finite and relatively small, rather than infinitely large, first became popular in 2003, when cosmologists noticed unexpected patterns in the cosmic microwave background (CMB) - the relic radiation left behind by the Big Bang.
The CMB is made up of hot and cold spots that represent ripples in the density of the infant Universe, like waves in the sea. An infinite Universe should contain waves of all sizes, but cosmologists were surprised to find that longer wavelengths were missing from measurements of the CMB made by NASA's Wilkinson Microwave Anisotropy Probe.
One explanation for the missing waves was that the universe is finite (see 'Universe could be football-shaped').
A mirror ball
"You can think of the Universe as a musical instrument - it cannot sustain vibrations that have a wavelength that is bigger than the length of the instrument itself," explains Frank Steiner, a physicist at Ulm University in Germany.
Cosmologists have suggested various 'wrap-around' shapes for the Universe: it might be shaped like a football or even a weird 'doughnut'. In each case, the Universe would appear to be infinite, because you would never physically reach its edge - if you travelled far enough in any direction you would end up back where you started, just as if you were circumnavigating the globe.
But the notion soon suffered a setback. Cosmologists predicted that a wrap-around Universe would act like a hall of mirrors, with images from distant objects being repeated multiple times across the sky. Glenn Starkman at Case Western Reserve University in Cleveland, Ohio, and his colleagues searched for the predicted patterns, but found nothing.
Undeterred, Steiner and his colleagues have re-analysed the 2003 data from NASA's Wilkinson Microwave Anisotropy Probe, looking for different shapes, including the so-called '3-torus', also dubbed the 'doughnut universe'.
Despite its catchy nickname, this shape is tough to visualize, says Steiner. The 3-torus is an extension of the familiar doughnut shape and can be formed from a rectangular piece of paper. You can imagine gluing together first one set of opposite edges to make a cylinder, and then the second set of opposing edges to make a doughnut shape, explains Steiner.
The 3-torus is formed in a similar way, but you begin with a cube and glue together each of the opposite faces. So if you were to attempt to exit one of the cube's faces, you would immediately find yourself entering again through the opposite one.
Other shapes are possible
Steiner's team used three separate techniques to compare predictions of how the temperature fluctuations in different areas of the sky should match up in both an infinite Universe and a doughnut one. In each case, the doughnut gave the best match to the Wilkinson Microwave Anisotropy Probe data. The team has even been able to pin point the probable size of the Universe, which would take around 56 billion light years to cross.
Jean-Pierre Luminet at the Paris Observatory in France, who proposed the football-shaped universe in 2003, likes Steiner's work. He agrees that the analysis shows that the doughnut is still a likely candidate, but adds that other shapes are also possible. "One must remember that the (football universe) is still alive and well," says Luminet.
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Starkman, however, is not convinced that Steiner's team has done enough to win people over. "It could be true that the Universe is small," he says, "but this doesn't provide an answer one way or the other."
Steiner believes that new and more precise measurements of the cosmic microwave background to be made by Europe's Planck satellite, which is due to be launched later this year, will help answer the question.
"Philosophically, I like the idea that th
Since the article is available on pay only, could someone please explain why the universe may not be a hall of mirrors, even if it wraps around?
Bollocks, mate.
Something bad is coming when people are suddenly anxious to tell the truth.
Continuity doesn't lead to an infinite regress. Attempting to get to the fundamentals of anything does. The crackpot on the site references Aristotle and then proceeds to make a claim that would cause infinite regress in the exploration of the properties of the subject. This is done even as he claims to refute the other evidence on the basis of infinite regress. Aristotle disapproves of your reasoning.
"Little is much when little you need."
Is that you, Zeno?
The fact is that continuity does lead to an infinite regress, something that even children can grasp.
Children may struggle with this perceived problem, but there are no mathematical problems with the model to anyone who has studied analysis.
PS - just because the theory of relativity or whatever may ultimately turn out to not be a 100% accurate description of reality doesn't mean that it is completely wrong, nor does it mean that any pet "theory" is right.
Many particle accelerators are doughnut shaped; indeed, it is speculated that God used a particle accelerator to create the universe.
While scientists disagree over exactly what the universe's origins are, religion has provided a consistent answer since the Earth's beginnings, over 6,000 years ago.
Also naturally doughnut shaped:
Anii
Cheerios
Red blood cells
This.
This too.
Can't forget this.
There is also an argument to be made that earthworms are doughnut-shaped when viewed end-on, and further that most life forms incorporate the same underlying architecture.
That was one idea, but apparently the gods decided that the costs of polishing the mirrors, even if just once every Kalpa, would be astoundingly prohibitive !
And what if they are? The last I heard, neither Einstein nor modern physics is infallible.
Oh sure, that's entirely possible. One big problem in proving it, though, is the fact that these theories have undergone and passed extensive experimental verification. They make predictions, predictions we can verify in reality. While we haven't tested every aspect or prediction, we know that things like time dilation and space dilation do in fact exist, in the exact amounts predicted by Einstein to our limits of being able to measure it. Could further measurement show Einstein to be inaccurate, and another theory prove superior? Sure, but that theory would have to at least account for what we have measured of Relativity.
And that's where all these "alternative" theories fail. Because they are 1) founded in scientific ignorance and 2) founded entirely in the egotistical notion that you can "up-end" all of science and prove all the scientists (that call you a loony) wrong, they always and consistently fail to explain the results of these theories that have been well proven. Usually by ignoring them, because they don't understand them to begin with.
It is easier to kiss ass and safeguard one's career than it is to bravely step up to plate and tell the emperor that he's buck naked and stupid.
Pfft, how much "bravery" does it take to stand up and tell a spectacled geek that they are naked? What wrath will be visited upon you? No, it's easier to come up with some stupid idea pulled out of ones backside that "proves" all modern physics is wrong, than to actually prove that all modern physics is wrong by coming up with an experiment that contradicts it. And remember, you can't ignore those experiments that have already been done.
Oh, and a continuous universe and infinite regress are not significant problems. There is no reason the universe cannot be continuous. It just would make it harder for us to prove certain things about it. Big whoop, we got over that long ago. On the other hand, quantum mechanics suggests the universe may not be continuous. So there you go. Which emperor is naked again?
The enemies of Democracy are
The problem with curvature is that it imples continuity (infinite divisibility), which leads to an infinite regress. Therefore curvature is an unacceptable concept in physic
So are you denying that space-time can be bent by mass/energy? Well guess what, you're provably wrong, because we've measured the curvature of space. You can call it "unacceptable" all you want. It exists. So, given a hypothesis that curvature can't exist, and a experiment that says it does, which must be wrong? That's right, the hypothesis. No matter how strongly you believe in it. Ask Michelson and Morley.
Oh, and give it up with this "infinite regress" BS. Infinite regress is a problem for formal proofs, nothing more. Godel already handled that, proving that there are true statements which cannot be formally proven. They can still be experimentally verified, and in physics that's what counts.
Besides, even accepting that the universe can't be continuous (QM suggests it is quantized), that says nothing about the overall shape of the universe. If the universe is quantized and there is no curvature, then you are simply moving in discreet quanta along a plane. What is so hard to grasp about moving in discreet quanta, but along a more complicated function? It's no different. Quantized curvature is no more impossible than quantized flatness.
The enemies of Democracy are
Is there anything they can't do?
Continuity doesn't lead to an infinite regress.
The only thing that is infinite is your stupidity.
So not only has Quantum Physics repeatedly proven that the computer running the universe in which we live works on integers for speed, that the universe simulator only refreshes things on screen,
but now we've also proven that it doesn't check for integer overflows ?
Man, our universe is just such a buggy piece of code. Probably hacked together in Perl.
"Sufficiently advanced satire is indistinguishable from reality." - [Tips: 1DrYakQDKCQ6y52z6QbnkxHXAocMZJE61o ]
I sure hope "Fuk Li", the JPL manager in charge of the program, grew up outside the U.S. Can you imagine growing up with that name! Yikes!