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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."
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.
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.
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.
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...
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".
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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
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.
Isn't there a multi-big bang theory
Ahh, you are referring to the Gang Bang theory?
Seven puppies were harmed during the making of this post.
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?
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.