Dark matter is sort of the opposite of light, name aside. It has mass, and cannot be observed aside from the side effects of its mass and gravity. It comprises roughly a quarter of all mass in the universe, 27%. That's a little more than all helium in the universe at about 23%
We know that nuclear reactions turn matter into light waves. Light has no mass, so where the hell do those particles with mass go? If dark matter and light are true opposites of each other...
electromagnetic waves - light without mass
dark matter - mass without light
... then I predict dark matter is created at the same time light is created in nuclear reactions. That could explain why the amount of dark matter is about the same as all non-hydrogen matter in the universe. What do you nerds think?
>I thought of this this morning in my phys 100 class, kek
>>8045422
>dark matter is sort of the opposite of light
No
And the rest of your argument falls apart from there
>>8045422
>> Dark Matter
>> Only 2% more than helium
>>8045442
It's called percentage points, you retard
>>8046055
>> Baryonic matter (inclusive of helium) accounts for about 4% of the energy density in the universe
>> dark matter is something like 25%
>> dark energy is around 71%
>>8046068
He specified his percentages with respect to different absolute quantities. So don't be a cunt if you have no frame of reference.
25% is the abundance of helium with respect to (I believe but may be wrong) total baryonic matter as predicted by big bang models and observed.
His dark matter percentage is with respect to the overall energy density of the universe as observed by (I think) the Wilkinson Microwave Anisotropy probe
>>8046366
Someone can correct me if I'm wrong but Im studying for an undergrad cosmology exam atm.
>>8045422
Dark matter is literally just matter that doesnt produce light. Dark energy is totally unrelated
>>8046373
Yeh. Completely different.
Dark matter is just a requirement for galaxies to have the rotation curves they display which can't be explained by solely considering the mass due to visible objects. Also used to explain certain gravitational lensing events.
Dark energy is responsible for the acceleration of the expansion of the universe. We really dunno what it is. Einstein kinda threw it into his GR equations on a whim because they allowed him to provide solutions, called it his biggest blunder and the launch of (i believe) WMAP confirmed it actually exists
>>8046382
>WMAP confirmed it actually exists
There was evidence for Lambda previously with clustering and supernovae results.
>>8046392
Wasn't aware. My cosmology professor makes it seem like he wants WMAP to give him a pearl necklace.
>>8046382
>Einstein kinda threw it into his GR equations on a whim because they allowed him to provide solutions
More specifically, because a static universe was aesthetically pleasing, so a repulsive term had to be included to balance out the attraction of gravity from eventually collapsing the universe.
But it turned out the Universe wasn't static (since it was expanding) and that he'd had no reason to assume it was, he took it back out in embarrassment.
And now it turns out the expansion is actually accelerating, so we've had to put it back in again.
(Note that dark energy isn't "negative energy"; it's a specific combination of energy and pressure.)
>>8046411
It was the shit (other than the beam problems and lack of polarisation). Unlike supernovae or just about any other test the CMB power spectrum is very clear cut, there are no monstrous systematics lurking. A re-calibration probably won't change all of your parameters. The data is also fantastically easy to use.
Planck is way better though.
