Saturday, 25 May 2013

The Discrepancy

Ladies, gents, bots, potentially sentient networks, a guest post.

This is brought to you by Richard Tee (@RichardTheGeek) after a Twitter discussion on the subject of Dark Matter and Dark Energy and whether or not they're a whole big ugly cheating fudge.  The post below is Richard's take on the matter, the long rambling bit of fiction in the menu on the right entitled "The Discrepancy" is my attempt, I thought I'd give "making it all up" a go seeing as a clear and coherent argument was in such good (single malt loving) hands.


The internet. For a computer scientist with a hankering for physics, the internet can be a fun (and scary place).
The other day, I was involved in a very good Twitter Chat with two online friends, the subject of which was the concept of dark matter and dark energy.
As one of my personal heroes Dr. Richard Feynman once said “It doesn't matter how beautiful your theory is, it doesn't matter how smart you are. If it doesn't agree with experiment, it's wrong.” – well Dr. Feynman I couldn’t agree more – sadly many people in modern cosmology think otherwise.

Why do you ask? Simple – we are wrong.

Before you hang me out to dry, kindly let me explain.

In the study of the universe, we have come across a slight problem – it seems that given our current equations and theories, we cannot account for roughly 96% of the matter that we think SHOULD be in the universe. In other words, the more we find out, the more it seems we don’t know … all the visible matter in the universe only adds up to 4% or so of the total amount of matter that should be out there!

If you haven’t guessed this is a problem.

So, what was the solution to this problem? Simple: Say that the remaining 96% of the “stuff” out there is simply, “dark” and thus not visible nor detectable by conventional means.

Simple right? … not quite.

A recent study from the AMS (Alpha Magnetic Spectrometer) was searching for positrons – which it found … that wasn’t the problem, the problem was that an expected results showing a “drop off” for dark matter was not present. Furthermore, given the nature of how we think dark matter behaves, we would expect it to be non-isotropic, meaning concentrated towards the direction of the galactic center. This was not the case: In fact it was nice and uniform.
So what does this mean? Nothing really. That in itself is a bad thing for the dark matter/energy group.
Of course, I am not saying that dark matter and dark energy doesn’t exist, but having it represent 90+% of the universe is a bit … far fetched.
Why am I so against dark matter/dark energy as the solution to our cosmological problems? It seems that it is just bad science.
Basically, as Feynman said, if the theory APPEARS correct, it can be assumed as long as the data supports it – at which point we need to re-write our theory to support the new data. This doesn’t seem to be the case of dark matter/energy. The observations seem to contradict our theory, and thus to “fix” the theory we happen to mention that it only accounts for 4% of what we can see.

The analogy I can make is spending. It is like a teenager saying they manage all their money very well … out of every $100 they keenly save $4, and the other $96 is unaccounted for… Would you let them manage your finances?

We may find out that one day, dark matter and dark energy are in fact present in very high quantities in our universe. However my gripe is that the fact that few people seem to be demanding a simpler and less exotic solution to the problem.
Ladies and Gentlemen, it is time to erase the blackboard and start from scratch on this one.


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