supersymmetrical
I’ve been listening to a new podcast: StarStuff by Stuart Gary. He reports and comments on the latest goings-on in the world of astronomy, physics and space exploration with his heavy Australian brogue. He talks in-depth about a wide variety of stuff, from the progress of the Mars rovers to the fledgling Indian space program to the latest discoveries beyond the Kuiper belt. I’ve been eating it up.
In a podcast from a few weeks ago, he discussed dark matter and dark energy, two substances that the physics community has postulated exist based on astronomical inferences. Physicists and astronomers noticed that, based on then-current models, there was far too little observable mass in galaxies to generate the gravity needed to keep the centrifugal force of their spinning from flinging them apart. So dark matter, as a concept, was proposed, a substance that doesn’t interact with normal matter in any way except gravitationally. Concurrently, the concept of dark energy was put forth to explain the observation that the rate of expansion of the universe is increasing. That acceleration requires an energy source, and unable to account for it observationally, enter dark energy. Together dark matter and dark energy supposedly make up 96% of the energy density in the universe, the remaining 4% being “normal,” observable, baryonic matter.
As mentioned, dark matter doesn’t interact with any fundamental force except gravity, which makes it exceedingly difficult to observe, and thus confirm its existence. However, scientists are trying various ways of observing it more directly, like the Large Hadron Collider that was in the news recently. And the Starstuff podcast a few weeks ago discussed another possible indirect observation of dark matter, this time from cosmic rays detected emanating from a (relatively) nearby galaxy.
The podcast also made a passing reference to Kaluza-Klein theory, a theory first published in 1921 and intended to unify two of the four fundamental forces using higher dimensions. Shortly after it was published quantum mechanics became the main focus of research in the physics community primary because of its ability to be confirmed experimentally, something higher dimensions cannot do, and Kaluza-Klein fell into obscurity.
But ever since I read Hyperspace, and even before then, I’ve been convinced that pursuing quantum mechanics in order to unify the four fundamental forces is barking up the wrong tree. Kaluza-Klein theory and higher dimensions, in spite of the fact that (in their present state) they can’t be experimentally confirmed, are a much more elegant way to quest for a TOE. Our last great breakthrough in physics, general relativity was accomplished by tinkering with fundamental assumptions about space and time and by extension, dimensions. Quantum mechanics, in additional to being supremely inelegant (something the artist in me and in most theoretical physicists have a strong aversion to), just seems utterly bound by the constraints of three spatial and one temporal dimension. If we’re ever going to unify gravity with the other fundamental forces we’re going to have to look at the big picture, think theoretically, and not try to derive the whole from the sum of the parts, little piecemeal observations here and there.
Dark matter and dark energy are an outgrowth of that manner of thinking. Clinging to four dimensions so tenaciously that you have to make allowances for imaginary substances like that starts to sound like theories people were clinging to a little over a century ago having to do with luminiferous aether, the imaginary medium by which light propagated, and rendered obsolete with the arrival of special relativity.
It’s time to apply effort to theoretical physics as opposed to empirical physics. We need to start leaning more of the deductive side of the scientific method, and not just the inductive. That’s where the next big breakthrough is needed, I’m convinced.