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Is the Universe Shaped Like a Funnel?
DrMorpheus writes "A new theory of the shape of the Cosmos posits that the Universe may be shaped like a medieval horn, according to Frank Steiner at the University of Ulm. This theory, if true, could explain several strange observations about the microwave background radiation. The Universe would be stretched out at one end into a long tube and flared out into a bell at the opposite end. The technical name for this shape is a 'Picard topology'. To quote the article, '...our Universe is curved like a Pringle, shaped like a horn, and named after a Star Trek character. You could not make it up.'"
For enlightenment, please read Flatland by Edwin A. Abbott. A very interesting way to conceptualize life in one, two and four-dimensional worlds.
This has been a test. If this had been an actual Sig, you would have been amused.
What do we mean by the topology of the Universe?
We sort of mean the 'shape'. It is easy to talk about 2 dimensional surfaces in a three dimensional universe - planes, spheres, funnels, etc. But the Universe has 3 (large) dimensions, not 2, so it is much harder. Normally, we think of the universe as a 3 dimensional equivalent to a plane - that is, in space, straight lines are straight, never curve back on themselves, and go on forever. Another common topologies which arise naturally from gravity theory are 'spherical' - where parallel lines eventually cross, and you can see the back of your head. The group in questions is proposing that the Universe is a 3d analog to the surface of a horn. Others have proposed 3d analogs to the surface of a doughnut....
How can one possibly determine what this shape is?
If the Universe is actually curved in some way, then light coming from distant objects will be bent on its way to us, distorting the images. For the global topology of the Universe, one wants to use the largest, most distant thing you can look at. The Universe is expanding and cooling. Light takes time to travel, so if you look far enought away, you can look far enough back in time to when the whole Universe was filled with a hot H-He plasma. This is called the Cosmic Microwave Background (CMB). Most recent topology studies have looked at the statistics of the fluctuations of this distant plasma for distortion in the image from what is predicted.
So, is this true?
Could be.... but the evidence is not compelling. The anomalies they are looking at are of rather low statistical significance, and the idea that the universe is just 'straight/flat' and boring still fits pretty well. And unfortunately, for the large scale stuff, the data isn't going to get any better. The problem is, we only have one Universe, and COBE and WMAP have measured the large scales as well as can be measured. The small scale distortions have more potential given upcoming experiments like Planck, and the WMAP year2 data.
actually, (61.74/60) is less than (60/58.27), not the other way round, but you are right to say that this makes 1.74 a smaller percentage of 60 than 1.73 is of 58.27.</nitpick>
frequency is a continuous property of a wave... whether you choose to select linearly or logaritmically spaced points is up to you. over large scales (i.e. multiple octaves or decades), it is generally more useful to choose logarithmically spaced points, because you want to treat low octaves with the same number of points as high octaves. over small ranges (here only 3.47 Hz or about 5.78% of the nominal 60 Hz), it makes sense to deal with linearly spaced points, because the imbalance between octaves cannot come into play. in this case, if you played the B-natural against 60 Hz and then played the B-flat against 60 Hz, the resulting beat frequency signals would sound essentially the same, as the difference between them would be only 0.01 Hz.