Slashdot Mirror
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.'"
Much like a dog staring at a shiny object, I'm fascinated by this but I don't understand it.
Jedi don't stand a chance.
HAD
Dark matter had better exist- otherwise, I've wasted a hell of a lot of money on that dark matter damage insurance I bought a couple years back...
Gentlemen, you can't fight in here! This is the War Room!
Well actually knowledge of its existence and how much of it exists will determine whether or not the Universe eventually implodes on itself in the "Big Crunch" or whether the universe will keep expanding at the speed of light forever. So technically speaking, "in the long run" it will matter quite a bit :)
Regards,
Steve
That's what I love about physics: it's so out there that you'd think the person who just said something like that was smoking crack, if he didn't have a PhD.
Gravity bleeding between universes...
Who needs science fiction?
Meep.
well, let's see here. 4% of postulated matter in the universe is known to exist. 96% of postulated matter in the universe is NOT known to exist. that's a fine fudge factor to have in a test, and might explain where budget figures come from in the government :-D
:-D
it certainly explains where a lot of my assignments come from at work, lol
if this is supposed to be a new economy, how come they still want my old fashioned money?
>> think about it - 1500 years wasted trying to make epicycles work.
Dang, their billable hours must have krunked the project.
Maybe if we wait another year the program will halt...?
Too bad they were so bent on epicycles, TRON has a much cooler cycle game and it works!
(-1, troll)
No its not, it just has a lot of "dark content" that you can't see but which weighs heavily against its moderation. ... really sorry, I couldn't resist.
This thread misses an important point. Even though Ptolemy's theory was wrong, it was a lot closer to the truth than previous ideas like "the lights in the sky are gods with flashlights." The point is that even theories that are wrong add to our knowledge by providing a starting place for deeper inquiries.