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What If Dark Matter Really Doesn't Exist?
sonar67 writes "According to The Economist: 'It was beautiful, complex and wrong. In 150AD, Ptolemy of Alexandria published his theory of epicycles--the idea that the moon, the sun and the planets moved in circles which were moving in circles which were moving in circles around the Earth. This theory explained the motion of celestial objects to an astonishing degree of precision. It was, however, what computer programmers call a kludge: a dirty, inelegant solution. Some 1,500 years later, Johannes Kepler, a German astronomer, replaced the whole complex edifice with three simple laws. Some people think modern astronomy is based on a kludge similar to Ptolemy's. At the moment, the received wisdom is that the obvious stuff in the universe--stars, planets, gas clouds and so on--is actually only 4% of its total content. About another quarter is so-called cold, dark matter, which is made of different particles from the familiar sort of matter, and can interact with the latter only via gravity. The remaining 70% is even stranger. It is known as dark energy, and acts to push the universe apart. However, the existence of cold, dark matter and dark energy has to be inferred from their effects on the visible, familiar stuff. If something else is actually causing those effects, the whole theoretical edifice would come crashing down.'"
There seem to be growing "hints" that something is wrong with current theories about the very nature and behavior of gravity. This includes alleged dark matter that cannot be identitied, planetary space probes with slight deviations from expected sun "pull" [1], and the fact that there is no identifiable "negative" gravity while the other forces do have negative values or particles.
[1] It was originally thought that heat generated from nuclear fuel cells was "pushing" the probes, but this was mostly ruled out because the heat lessens over time, but the pull was constant.
Table-ized A.I.
Sure, in the long run it doesn't matter.
That is, of course, if we keep testing it and trying to see if it is true. (Or the closest approximation of 'true' we have been able to come up with.)
It matters now if it is not true because then we know we need a better theory. And that means we either didn't understand something we thought we understood, or that we hadn't explored our understanding fully. Either way, there is likely something else that will be affected...
'Sensible' is a curse word.
"Do you really have to prove God exists before you'll believe?"
;)
As a matter of fact, yes.
Some people get by fine on faith and that works for them. I've known many happy faithful people and I sometimes even envy that quality in them.
But that just isn't how I work. I look at the world with an innate need to figure it out. This makes it impossible for me to take any religion literally.
I suspect this is common with many geeks.
I always thought this was an interesting an odd part of modern science and cosmology. Why should we assume occam's razor, that simpler explanations are better? Why should the universe be simple and elegant?
You have misunderstood Occam's razor. It doesn't say that at all.
Occam's razor, in its original form, translates to "Do not multiply entities unnecessarily". That has been modernized to "The simplest explanation is usually correct", which is close, but not exactly the same.
What Occam's razor really means is: given two (or more) possible explanations of a phenomenon, with no evidence favoring one over the other, assume that the simplest one is correct.
For instance, if I find a pinecone lying on the ground under a pine tree, the simplest explanation is that it fell off of the pine tree. Sure, it might have been planted there by invisible space aliens in conjunction with the Illuminati acting in strict accordance with the Masonic doctrine of the Coming of the Pine Cone King, but since there is no evidence to favor one explanation over the other, I should assume that it fell off of the pine tree.
That doesn't mean that it did fall off the pine tree, and it doesn't mean that I might not change my mind as more evidence is found. It also doesn't mean that I shouldn't look for more evidence and try to determine the origin of the pine cone with greater accuracy. That isn't what it says at all. It just means that until such evidence arises which would cause me to revise my view of things, I should assume the simplest explanation that fits the facts. The explanation should only change when the known facts do, or a better explanation is found.
ZFS: because love is never having to say fsck