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Our future, our universe, and other weighty topics


Monday, August 11, 2014

Ornate Wacky Cosmic Speculations Sold as Science

I remember long ago when I was a teenager hungry for knowledge about the universe that fascinated me even then. Back in those days there was no internet, nor were there any of the great science cable TV shows that we now have. So to quench my thirst for knowledge about science and the universe, I would almost always use the public library. There were two great magazines I would read: a thin little weekly called Science News, and a monthly called Scientific American. Science News seems to have undergone almost no change in the past 40 years, and when I see a copy now in the library I get a kind of time-warp sensation.

But the Scientific American magazine seems to have changed. Perhaps the editors have felt a need to resort to sensationalism in order to keep up their readership. We have an example in the latest edition. The cover is dominated by a huge headline: The Black Hole at the Beginning of Time. When we go to a page on their online site, the headline says: The Black Hole That Birthed the Big Bang.

Wow, so I guess with this breathless headline, scientists must have finally figured out that “origin of the universe” thing, right? Wrong. The article in question is a discussion of a purely speculative theory, a theory that is one of the wackiest and most ornate pieces of baseless speculation since the Maori story that all of creation stems from the six sons of a primordial couple named Rangi and Papa.

I would link to the Scientific American story directly, but it is blocked by a pay wall. But the same theory advanced by the same authors is found at this link.

Here is how the authors describe their theory:

We describe a braneworld description of cosmology with both 4d induced and 5d bulk gravity (otherwise known as Dvali-Gabadadze-Porati, or DGP model), which exhibits this feature: The universe emerges as a spherical 3-brane out of the formation of a 5d Schwarzschild black hole.

Here the 4d and 5d refer to dimensions. The authors are speculating about dimensions other than the known three dimensions of width, height, and depth. This should immediately alert us that they are engaging in a baroque flight of fancy, rather like someone speculating about vast galactic empires.

What does this phrase “braneworld description of cosmology” mean? Braneworld cosmology might be described as an ornate speculation built on top of a baroque speculation built on top of an intricate speculation. Let's sort out the tower of speculations.

At the bottom of the tower of speculations is supersymmetry, an ornate theory for which there is no evidence (some say it is on “life support” after Large Hadron Collider observations have failed to back it up). Built on top of supersymmetry is string theory, an even more ornate theory which also is not supported by observations. Then built on top of string theory is brane cosmology. As wikipedia notes in its article on brane cosmology, “There is no experimental evidence for this hypothesis, nor is there any definite need for the brane multiverse in M-theory or string theory.” Then built on top of brane cosmology is the new theory of Afshordi, Mann and Pourhasan.

So their theory is an ornate speculation built on top of an ornate speculation (brane cosmology) built on top of an ornate speculation (string theory) built on top of an ornate speculation (supersymmetry). What is hilarious is that some people must be seeing Afshordi, Mann and Pourhasan's theory featured on the cover of the venerable old magazine Scientific American, and many such people must be confusing the theory with science, which it is not. It is actually a super-speculative theory very distantly related to scientific observations, which is an entirely different thing.

The following visual illustrates the point. We see a yellow circle representing science. To its left we see a blue circle representing speculations based on science. There is a big arrow pointing from the blue circle to a trashcan. This is because most speculations based on science end up being discarded. There is a much smaller arrow pointing from the blue circle of speculation to the yellow circle of science. This represents the small number of speculations derived from science which end up becoming established science.


science speculation

Afshordi, Mann and Pourhasan's speculations are very much in the blue circle, not the yellow one. Their speculations have an overwhelming likelihood of ending up in the trashcan. Sadly, magazines such as Scientific American cause people to confuse something in the blue circle as something in the yellow circle.

According to a Science Daily article, part of the inspiration for Afshordi, Mann and Pourhasan's theory is a dissatisfaction with the standard cosmological theory that our entire universe arose from a point of infinite density called a singularity.

Science Daily says, “The problem, as the authors see it, is that the big bang hypothesis has our relatively comprehensible, uniform, and predictable universe arising from the physics-destroying insanity of a singularity. It seems unlikely.”

Yes, quite a mystery; but that mystery persists.

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