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Is the Universe a Hall of Mirrors?
PhysicsWeb is running an article by one of the researchers who has developed the theory that the universe may be finite, rather small, and soccer-ball shaped. The question is still open; it's one theory that fits cosmic microwave data from the Wilkinson Microwave Anisotropy Probe (WMAP). Apparently testing the theory by looking in the indicated way through the WMAP data would so far be computationally prohibitive. From the article: "The Poincaré dodecahedral space can be described as the interior of a 'sphere' made from 12 slightly curved pentagons. However, there is one big difference between this shape and a football [soccer ball] because when one goes out from a pentagonal face, one immediately comes back inside the ball from the opposite face after a 36 degree rotation. Such a multiply connected space can therefore generate multiple images of the same object, such as a planet or a photon. Other such well-proportioned, spherical spaces that fit the WMAP data are the tetrahedron and the octahedron."
Everyone knows the universe is banana shaped.
Bable Fish translation: "You, the reader of this article, are not nearly as smart as you thought you were. Don't feel bad about not being able to grasp anything in this article other than the word "the". Go to bed and do not look up at the sky at night for a very long time."
Lawrence Person (lawrencepersonh@gmailh.com (remove all "h"s to mail)
http://www.lawrenceperson.com/
No, nothing has to be "containing" it. Think of it like walking on the surface of the Earth. If you look in either direction you can see pretty far and you might imagine that the Earth goes on forever. If you start walking, you will walk all the way around the Earth and end up exactly where you started. The Earth simply curves back on itself. You could walk around the Earth forever and never reach a boundary where Earth ends, but the Earth itself is still finite.
As to what this soccer ball universe could floating in, well, the question itself is probably the largest issue. We don't know the answer, but the it could very well be that there is no "outside of the soccer ball". The universe could be all that there is. There could be no "beyond" the universe or "outside" of the universe. It is hard concept to visualize, but that is pretty much true of any concept that outside of the traditional Newtonian world.
Once you leave the safe world of Newtonian physics you need to develop a superhuman ability to try and NOT visualize the universe on the grand scale of the quantum scale. Human intuition and visualizations is was built for Newtons world. Once you leave that world, it breaks down and fails to be much help.
Q: Does not a soccer ball require a soccer ball-sack?
A: Therefore, God exists.
If the universe has 12 faces what happens to you if you exactly hit a boundary between faces? Do different bits of you come out of different opposing faces? If so, where does the energy come from to break you into components?
Maybe not a big issue for a spacecraft but what happens if a neutron star hits a boundary?
http://michaelsmith.id.au
If you can infate a soccer ball and make it grow, certainly I would imagine the Universe can grow.
Maybe there is currently a finite amount of material. Who says that material can't get relatively further apart from itself? Either things can be moving away from each other occupying more space, OR the material itself, the "dots", are getting smaller and smaller making it appear we are gaining space.
Isn't there a multi-big bang theory that states that new material can enter our Universe in this fashion? Perhaps our current Universe had no single beginning, but new stuff is being added to it all the time. How many mutli-player online gamers have an ever-expanding world? New levels are constantly being added.
If anyone's looking to understand this, the book you need is "How the Universe Got Its Spots" by Janna Levine. It covers all the apparently valid but actually nonsensical questions that people have when they first hear about this (what's the universe inside then? what happens at a boundary? etc), and it explains it in such a way that you don't need a degree in topology to understand it.
World peace can be achieved by transferring to a carebear universe
D6 63 0D 70 89 81 BB 8E 7B 7C 5F 5D 54 EA AB 73
The article mentioned is well over a year old. The outstanding analysis of data due in 2004 has been completed. The validity of the information is being questioned Although it would be fun living inside a football.
Nope, ball with 12 slightly curved pentagons => 30 edges + 12 faces => 30 + 12 = 42
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
If our universe resembles a video game, could it actually be a video game?
:D
That logic is fallacious, even if the observable universe is a "simulation", then this simulation runs inside a real universe, and we're at the start again figuring out what the universe is.
Plus I subscribe to another logic: if the universe is similar to a video game, then it's because as video games increase in complexity they start to approach the model of a little universe
soccer-ball shaped
I think these cosmic topologists are going to have to kick this theory around for a while before they achieve their goals.
And the brethren went away edified.
This article is about 15 months old and discusses this in the context of 1 year of WMAP data. Since then, the WMAP 3-year data has been released. I would be curious to see how this affects the theory. I believe that the WMAP 3-year data gave something like Omega = 1.010 +/- 0.001. Thus this theory seems to balanced on the knife edge. It's an interesting idea, but I have my doubts.
God doesn't play dice, he plays soccer...
Soccor Balls are not dodecahedra. They're truncated icosahedra.
Actually, it's a spheroid, 705 meters in diameter.
It's actually just a series of tubes, and it's definitely not a dump truck.
Hmm.. just counted the edges on a d12. Maybe there are 30 after all.
Software patents delenda est.
Mmmmmmmmmmmmm..... universal donut....
*drool*
The shape of the universe is... (rolls dice) dice shaped! It's all one big boring D&D game
I do not know the details of this, but I strongly suspect that the universe is still continuous in this model. In that case things are set up so that if you hit a boundary between two faces, then the two corresponding faces that you come out of are also adjacent, meaning that you would not notice that you have hit a boundary. Possibly the faces are just a way to explain what is going on, and there would not need to be any actual boundaries that could be detected.
Bjarke Roune
http://www.simulation-argument.com/
it's in my head
Err... the edges are shared, so there are less than 30. I'm trying to figure out the exact number but my maths is too stale.
No, the exact number would in fact be 30. The edges are indeed shared, which is why there are less than 60 (5 * 12) edges.
"Convictions are more dangerous enemies of truth than lies."
The mistake is thinking of there being an actual boundary. You need to think of it more like the crotch on a pair of pants - imagine that each pentagon has a tube connected to it, and you run it to the other side and connect it up with the appropriate twist. Then imagine that you turned the whole thing into rubber. There is no longer a sharp edge, just a blobby series of tubes joined by a bunch of U-shaped pant crotch things. The fact that two particles that were very close to each other before they entered separate tubes has no bearing at all on how far they will be after they enter the tubes. It may have great bearing on the details of the force laws that they interact under (basically, every "mirror" particle has to be accounted for, including the infinite copies of the particle itself; this is an incredibly delicate self-action problem even for the simplest multiply connected spacetimes).
You trip because those bastards as OSHA didn't get a warning sign put up. Time to sue the universe, sight cases of previous soccer ball injuries as proof of negligent design by the creator/creator(s)/thing/fuji heavy industries/spagetti monster/who ever made this thing.
If you have noisy data and you keep analyzing it enough, you'll eventually find some bizarre model that fits it better than a more plausible model.
It's probably best not to have a firm opinion on the shape of the universe until a lot more data is in.
The freaky thing is that the dodecahedron has been associated since ancient times as representing "the Universe".
l
http://www.kheper.net/topics/cosmology/solids.htm
We know where leadership by an anti-intellectual "strongman" who scapegoats minorities and likes boisterous rallies goes
#1) Respect the privacy of others. #2) Think before you type.
I've always wondered if you raised a kid the right way if he would be able to have a quantum intuition. I mean, despite not being known directly to me, having been taught very early in my life about (the classical model of) atoms makes them seem intuitive, even though I would imagine they would not be to someone 500 years ago.
Of course, it might all be wasted if our final Theory of Everything has a new way of looking at quantum effects. Which I, personally, think it will. My personal candidates include Bohm's interpretation (which goes a lot deeper than Wikipedia will tell you; see Wholeness and the Implicate Order's later chapters for details), Heim theory, loop quantum gravity, and string theory. But I am fairly confident that at least the last of these, and probably all of them, will not survive in their current forms; they will have to merge and evolve first. (IANAP, but IAA Caltech undergrad planning on majoring in/doing research in physics for what that's worth.)
"May the days be aimless. Let the seasons drift. Do not advance the action according to a plan."
"Who's Moriarty?"
:P
That's probably what the person who modded my parent post down was asking themselves, too, I'd guess. Shame on those of you who missed the ST:TNG reference!
Please see the Wikipedia page for Professor Moriarty and on that page, scroll down to where it says "Moriarty in pop culture" where it includes the bit about the ST:TNG episode where "the three trapped crewmembers programmed the holodeck inside the holodeck to create a holographic simulation of the outside world, leaving Moriarty and the Countess safely stored in a databank aboard the Enterprise." At the end of the episode, Picard mentions something about how we all may simply be inside such a device sitting on someone's desk somewhere.
I knew it! The universe is shaped like a game of Pacman. I didn't waste the 80s on nonsense time-wasting after all.
... and then they built the supercollider.
Strangely the boundary between 2 faces is actually shared by 3 faces. Here's a figure of it. See for example how the edge "g" is a boundary between faces IV and V, faces V and VI, and faces VI and IV.
The answer is always 42, you can't argue with Douglas Adams.
BTW: Put down the slide rule, you just need to realise every edge has exactly two adjacent faces.
And did you exchange a walk on part in the war for a lead role in a cage? - Pink Floyd.
The human mind is the product of millions of years of evolution designed to think in a Newtonian way. You are hardwired to think Newtonian. This hardware does very deep and is a fundamental piece of your core persona. Consider for a moment that if you toss a ball, a dog can jump up in the air and snatch it. This gives you an idea of how hardwired we are to think in Newtonian terms. This is an an ancient way of thinking that goes back well before we were primates, much less full blown humans.
Anyone can tell you what happens when you hit one object against another or toss one object against gravity at a certain angle. Even small children know roughly where a baseball is going to end up the second you release it from a throw despite the fact that the real calculation would take someone a few minutes to make. With quantum mechanics, you are never going to have that child like grasp of what happens when two atoms start interacting.
While we do make visual models to understand quantum mechanics, they really are only a crude ways to give our poor mammalian brain some straws to grasp at. We can visualize orbitals to some extent, but anything deeper then that kicks human intuition which has been developed to deal with a Newtonian world in the balls. You really can only truly 'understand' quantum mechanics and general relativity with math. And not just simple math, but ugly math that kids go to college for years to understand.
Without the hardwired machinery to give us answers like what we have for Newtonian physics, there is no ability to develop and "intuition" for quantum mechanics. Quantum mechanics is ugly math combined with concepts that have no Newtonian world analogy. Let the kids know that this stuff exists, but keep them in their happy Newtonian world where their hardwired physics engines can pick up the slack. Save quantum mechanics for after they know calculus.
Hm. That's an interesting idea. One of the articles at that site includes the observation that such a simulation wouldn't have to simulate everything down to the greatest level of detail at all times, but could conserve computing power by just simulating things that are under direct observation.
Isn't that what actually happens in quantum-level experiments? If we are observing the double slits, the photons do one thing, but if we're not watching the slits, they do something else?
The issue of "what is the soocer ball contained in?" is answered by the fact that the soocer ball is the universe, ie. All of space and time. Space doesn't exist outside the universe, therefore there is no need for the universe to be contained in anything.
...and that is all I have to say about that.
http://jessta.id.au
Yes, they can, but that does not make them "hardwired" to do Newtonian physics; physics is the mathematical description of the real world, and so someone who lives in the real world and experiences it will have intuition into how physics works. If we lived and experienced in the quantum or the relativistic, we would have intuition into how that works as well. However, if you have never experienced something (even Newtonian physics), then you have no intuition about it because it is not something hardwired. Examples: on this very site a while back, there was a heated discussion about what would happen if there were a a tunnel bored completely through the Earth and you fell it in. What would happen? People disagreed. Also, Total Internal Reflection. I don't think that a dog, or a child, or anyone who hasn't taken a physics course or read about fiber optic cables would know about this. There is no intuition about it, but it is Newtonian physics. Physics is not hardwired into anybody's or anthing's brain. Our seemingly innate grasp is the ability to find patterns in the behavior of things, which is why the dog will know when to jump to catch a ball, or why the child knows where the ball will land (approximately). If we have no experience to find patterns in, we won't know our heads from our asses, metaphorically speaking.
As a consequence, you can grow intuition as you work with something. Which is why if you do enough quantum mechanical calculations, you will begin to have a sense of "what looks right," to have intuition about how quantum mechanics works. True, because we can only express quantum mechanics, our intuition in mathematical, but just like the physics student can translate the mathematical expressions of Newtonian physics into consequences in the real world (i.e. if the momentum of A is bigger than B, then they will both move mostly in the direction of A if they have an inelastic collision), the student of quantum mechanics can say "This Hamiltonian of an electron doesn't have any nodes. Then it must be in an s-orbital." Just because we are not as intimately familiar with quantum mechanics as we are with Newtonian physics because we live in the latter, not former, doesn't mean we can develop an intuition into how the former works.
It has been a nervous year, with people beginning to feel like Christian Scientists with appendicitis.
If we live inside a simulation, then, to us, that simulation *is* the universe. What lies "outside" of it can only be determined if the creators of such a simulation wanted us to do so. Is it possible for a video game character to leave a computer game and enter the real world (or at least what we consider to be the real world)? Only through the intervention of it's creators (i.e. us). The same would occur if we ourselves are constructs of a simulation.
Don't you just hate it when people reply to your signature?
I think the word I'm looking for is hypercube, but I mean to apply it to the number of sides a dodecahedron has.
Going through one side will result ending up coming through another side. (Anyone ever have dreams of being stuck in a room, you go through the door, only to end up in the same room as before?)
Picture yourself in an empty room like this. You can see through the sides, and you see yourself like in a hall of mirrors. You pass through the walls only to end up in the same room.
Imagine release millions of tiny superballs, which we will call photons, in the room. Now, imagine there is another object, a big round object in the room, that isn't moving to start with.
All these superballs going in every single direction start bouncing off you, pushing you around. However, since there were few, if any, superballs between you and the big round object to begin with, there is less "pressure" inbetween you and the object, so the superballs on the outside push you towards it.
The big round object is moving slower as the superballs bounce off of it because it has more mass, however, you are pushed towards it ever quicker. More and more, you fall faster and faster towards it.
I'd say it's more like asteroids, since it doesn't matter which side you leave from...
09F91102 no, 455FE104 nope, F190A1E8 uh-uh, 7A5F8A09 that's not it, C87294CE no. Ah! 452F6E403CDF10714E41DFAA257D313F.
So you are saying the Universe is nothing more than a series of tubes? Are you a senator? Alright, come out with it!
Okay, this is off topic, but it must be said. Your "spacetime is a bunch of rubber U-shaped pant crotch things connected by a blobby series of tubes" metaphor really deserves its own page on the uncyclopedia, http://uncyclopedia.org/wiki/Main_Page. I'm far too lazy to do it myself, so consider this a challenge.
Futurama depiction
It's less a fallacy and more "OMG I watched the Matirx, and like, it was deeeeeep, man!"
Amazing how many armchair philosophers come out of the woodwork when a movie has kung-fu and guns in it.
Endless arguments over trivial contradictions in books written by ignorant savages to explain thunder in the dark.
'The Road to Reality' (Roger Penrose) http://www.amazon.com/Road-Reality-Complete-Guide- Universe/dp/0679454438/
Great discussion about physics laws and math, one of the bests titles of Mr Penrose, and yes, the ' dodecahedral/tetrahedral/octahedral space' possibilities are also explained from the ground up.
What's in a sig?
You're essentially correct, under this model you end up with a continuous space. Perhaps the easier way to see how it works is with a simpler example like a torus: you can make a torus (donut shape) from a flat piece of paper by first rolling it up into a tube (identifying the top edge with the bottom edge) and then looping the tube around (identifying the two ends of the tube with each other). Thus you can think of the flat piece of paper as a torus by imagining that when you pass off the top edge you appear at the bottom edge, and when you pass off of one side you appear on the other. Now, what happens at the corner (the equivalent of an edge of the dodecahedron)? A quick check and you'll see it all works out: in some sense you might be "broken up" with half of yourself on one side of the paper, and half on the other, but remember those sides are connected together, so so are you.
The same trick works with the dodecahedron, you just have to get the identification of faces right. On passing out through a fae you'll appear on the opposite face, rotated. Take a quick look at a dodecahedron (here's an example that is translucent and rotatable so you can look around) and you'll get the idea. Looking through the dodecahedron from one face you can see the opposite face doesn't align: it's at an angle - hence the rotation. Visualsing where you'll come out as you approach an edge (and where the other face of that edge will result in you appearing) you'll see that the whole thing in indeed continuous; the edges present no problems.
Craft Beer Programming T-shirts
That is not quite true. Quantum mechanics technically still holds at the macroscopic level. However, Newtonian physics is an "approximation" that is incredibly good in intermediate scales (i.e. not relativistic or quantum).
Of course the universe isn't truly Newtonian. That said, Newtonian is how we perceive it in our day to day lives. Sure, there are electrons and atoms bouncing all around me, but the only thing I see is a flat desk with gravity pointed straight down.
I can guarantee you that the dog is not doing newtonian physics in his head; neither is he hardwired to do it that way. If you throw a ball at a puppy, he will not be able to catch it right away. Just like a little kid can't. We aren't hardwired to "think Newtonian." As it is, Newtonian physics are a representation of the world we live in, not the world itself.
Do you truly and honestly believe that in the millions of years of evolution in a world that looks like a teenagers physic books opening lessons that nothing has been hardwired to deal with a Newtonian outlook on the world?
Take a gazelle. Drop it out of its mothers womb, and watch as within an hour it is performing a balancing act in modern robots struggle to mimic. This stuff is hardwired in.
Take a baby. Try and teach it calculus. Spend every single day trying to teach it calculus, and see how successful you are. The baby is going to find this utterly impossible because calculus is something we have absolutely zero evolutionary adaptation for. When we learn calculus, we learn it through blood, sweat, and tears. Now take a baby and try and teach it English. Spend every single day talking to the baby and trying to teach it English. You will probably take the better part of year before you start to see any success. It will probably take the child until he is in high school before the child has mastered the language. Language comes quicker then math because we have entire centers of the brain that have been devoted to learning it. It is still a new evolutionary adaptation on the grand scheme of things, but there has been some time for it to get a foothold in our brains.
Now, try and teach a baby how a Newtonian world works. The baby is going to understand that something coming towards its face is going to hit, that objects are solid, and that things fall in parabolas long before it even has the beginnings of muscle control do anything about it. A baby will start making sense out of the photons bouncing around in a deeply intuitive way almost instantly.
A young child is significantly faster and more accurate then Ph.D. in physics can ever be without the aid of a computer when trying to predict a trajectory or what happens when an object is struck. This stuff is so hardwired into us that we don't even think about it. Hell, we CAN'T think about it because it is so hardwired into us. Acting in a Newtonian world comes easier then breathing.
However, if you have never experienced something (even Newtonian physics), then you have no intuition about it because it is not something hardwired. Examples: on this very site a while back, there was a heated discussion about what would happen if there were a a tunnel bored completely through the Earth and you fell it in. What would happen? People disagreed. Also, Total Internal Reflection.
Of course we don't have an intuitive understanding of what happens when gravity is doing anything other then pulling us down or any we are bouncing things through a fiber optic cable. Why in the hell would any species evolve to understand such things? When I say that we understand Newtonian physics, I don't mean every single rule and law that falls under "Newtonian physics". I mean that we perceive the world like the first few chapters of a high school physics book.
Further, the intuitive jump for understanding complex but still Newtonian things is a small jump compared to trying understand quantum mechanics or general relativity. After a
"Paging Mr. Dick, Paging Mr. Phillip K. Dick, you have a visitor at the front desk."
An individual with a quantum-intuitive understanding of the world might be very difficult for the rest of us to recognize. Such a person would have a lot of trouble perceiving cause and effect in the way we do, and would probably have no concept of determinism or even certainty. They would be able to see more dimensions than us (if such theories are physical), and would be unable to correlate these dimensional relations to objects within our understanding: if you are a sphere, you can describe yourself to a plane by saying "I'm a bunch of circles," but this really is incomplete and the plane really would be hopeless to have a complete understanding of you. Such a person may appear at times clairvoyant or at least extremely intelligent, but much of the time incoherent and simply apart from the human race.
In short, such a person would either be autistic or the Mua'Dhib. Read PKD's "Martian Time-Slip" or "Dune" for examples of people with quantum knoweldge or understanding, and how is basically makes them appear mad much of the time.
Don't blame me, I voted for Baltar.
Better yet, buy one.
Tom Swiss | the infamous tms | my blog
You cannot wash away blood with blood
Or maybe playing on a non-PvP server.
I seem to remember a speculative fiction novel in which the protagonists are on a ramscoop ship whose drive goes funky and won't shut down. (it's lurking on my shelves somewhere; but I cannot remember the title yet)
Long story short: they keep increasing in speed, ever nearer 'c' (the scoop field strengthening with the increasing speed so they don't collide or get fried), and eventually end-up 'wrapping around' the universe and seeing how things have changed each time they pass certain galaxies/clusters (time dilation helps here). As the wrapping progresses, they also notice all else 'cooling down' and regressing back to Origin where there is eventually another 'big bang', they get their drive fixed and start to slow down, and ultimately (conveniently) find an earth-type planet to land on.
Sound familiar to anyone?
"It's time to take life by the cans." ~ Bender ("Bendin' in the Wind", ep. 3-13)
"Asteroids" the video game takes place on a toroidal surface. You go in any one direction and eventually come back from the direction you were heading away from. The "torus", if considered as a 2D surface embedded in 3D space, can have its hole in the yz plane, the xz plane, or any plane really that contains the z axis, perpendicular to the screen. Within the 2D space defined by that donut surface, the orientation of the hole in the higher 3D space has no observable effect. Pac-Man, for its part, can be considered to have taken place on the surface of a cylindrical 2D surface embedded in a 3D space, not necessarily a toroidal one, since there was no magic tunnel connecting the top and bottom of the maze.
This is different: "an object that travels away from the Earth in a straight line will eventually return from the other side of the universe, having been rotated by 36 degrees in the process". So, it's just like Asteroids except the ship is pointing in a crooked direction when it reappears, off by some predictable angle. This would be a real problem for a game like Pac-Man, because of the way the controller works. Asteroids could accomodate the situation rather easily since left and right in that game control rotation instead of absolute direction, and applying continual thrust will keep the ship going straight even if it comes back with a cockeyed trajectory. Also, the maze and controller in Pac-Man, entirely based on NSEW directions, would present real headaches. Asteroids has no maze and the ship can point in any arbitrary direction, not just four.
The minimum radius of the soccer ball (according to this group) is 43 billion light years. The Big Bang was 13.7 billion years ago, but the actual horizon is 53 billion light years and not 13.7 billion since the universe wasn't always this big and the first few light years covered by the earliest photons have expanded to have a large contribution to that 53 billion. This little detail would present a challenging user interface problem for Asteroids. Now that I think about it, that might be less lame than the original Asteroids.
From any vantage point the furthest radiation visible is the microwave background. Beyond that, the light would have had to have been emitted earlier, at a time when the universe was more opaque. (Charged particles had yet to combine and emit background-radiation to form neutral, transparent matter less efficient at scattering light.) Past the microwave background, we "see" the early universe along all lines of sight as a completely opaque, black sheet, which emits no light of its own, absorbs all light, and which lines the boundary of what is for us the observable universe. It's like, how much more black could this be? and the answer is none. None more black. But these guys are saying that since 43 is less than 53, you can see the same patterns of microwave background radiation being emitted from various points in the sky, inside this opaque layer, in a pattern consistent with this dodecahedral symmetry. It's like God really does play dice, except he plays with those geeky 12-sided Dungeons and Dragons dice. Stuff like this has to make you wonder. Why 12? Who ordered that? What would have been wrong with a flat, spherical, tetrahedral, cubic, octahedral, or icosahedral universe? From a video game design perspective, a cubic symmetry would have been so much easier. In my humble opinion, God should have seriously considered creating a six-sided universe instead.
Even if you could reach the "edge", it's not like you would even notice anything, like a lot of these posts seem to be assuming. You wouldn't hit some sort of wall and go "splat". You'd just sort of relocate, rotate, and keep chomping away obliviously like Pac-Man does when he does his thing. We have no evidence that some anisotropy exists in the topology of the universe everywhere but here as if the universe really is centered on us and our galaxy, so that it changes somehow within a sphere that surrounds us. There's most l