Dark Matter constitutes 85% of the total matter in the universe

And yet we know very little about what it is or could be.

I personally think their is an undiscovered subatomic particle that could potentially explain some of its properties.

Top | Newest First | Oldest First

SomeMichGuy · M

@QueenOfZaun

Ummm...there's a reason it is called "dark" matter.

And this is wrong (sorry for putting it here, I can't reply to that thread):

Also it’s important to note that just because we can’t directly observe it doesn’t mean it does not exist. For example we actually discovered the existence of black holes simply using mathematical equations. We never physically observed a black hole until about a hundred years later.

There were four objects initially predicted through mathematical solutions to Einstein's field equations: black holes, white holes, wormholes, and tunnels through hyperspace. Astronomers went looking for them.

Only black holes were found, in 1971, 55 yrs after Schwarzschild's solution.

Analysis of the other three predicted solutions showed that they were unstable solutions. Only black holes (term invented by John Wheeler) were mathematically stable.

Mathematical "discovery" of a proposed real object isn't a true discovery until it is confirmed via observation.

QueenOfZaun · 26-30, F

@SomeMichGuy

That’s not quite right.

Black holes were predicted to exist by Robert Oppenheimer through the Oppenheimer-Synder model in 1939. As it turns out, Oppenheimer’s math was correct. 30 years later we would find observable evidence of black holes.

“Mathematical "discovery" of a proposed real object isn't a true discovery until it is confirmed via observation.”

Yes. That’s why theoretical physics is called “theoretical” physics. It’s considered theoretical until we find direct observable evidence to prove it. 🙄

johnbk97301 · 41-45, M

My My personal theory is the kind of like string theory you have all these other dimensions realms planes realities whatever word you want to use to describe but it's a place that we are in this dimension unable to see physically but it's there so if you have this endless amount of other dimensions just outside of our own that much physical matter no matter what dimension it's going to be in if it's still in a if it's still in our space that much matter it's going to have some sort of effect on our reality which would account for all this gravity from something that we cannot see

DownTheStreet · 56-60, M

There are other theories that do not require the presence of the never observed dark matter and dark energy - but because they are not entirely within the academic establishment, they get discredited … but give it time.

View 1 more replies »

DownTheStreet · 56-60, M

@QueenOfZaun well, I don’t have a PhD in physics but I do know support for the leading theory is not universal, and I know the power of the “institution” to crush dissenting voices. I mean, ask Galileo …

QueenOfZaun · 26-30, F

@DownTheStreet It’s interesting that you said dark matter has never been observed when we’ve seen it interact with the radiology of sub atomic particles.

Also it’s important to note that just because we can’t directly observe it doesn’t mean it does not exist. For example we actually discovered the existence of black holes simply using mathematical equations. We never physically observed a black hole until about a hundred years later.

ElwoodBlues · M

@DownTheStreet As far as I know, the big evidence for dark matter is
(1) the velocity profile for rotating galaxies

(2) gravitational lensing by galaxies.

https://blogs.ucl.ac.uk/science/2015/03/27/the-dark-matter-of-gravitational-lensing/

There's also an inference, (2a) which says that if dark matter particles were moving really fast, they wouldn't be able to clump around galaxies, so dark matter must be relatively "cold."

(1) is based on Newtonian mechanics which has served us pretty well for the past 350 years, while (2) depends on general relativity, which has fixed problems with Newtonian predictions around intense gravity fields.

You can say yeah, time to abandon Newton & Einstein, but if so you need a replacement theory that makes all their predictions on the scales where they've been verified. I don't know of any substitutes for general relativity.

sstronaut

Heck, we barely know what is in the water under a certain depth...

DeWayfarer · 61-69, M

Just to throw something wild into this discussion, I make a post regarding temperatures below absolute zero that referred to dark energy.

The postulate made in it is very interesting. Anything that gets to a certain extreme temperature behaves as it's below absolute zero.

Just a clip from my post, which includes a video about temperatures below absolute zero.

https://similarworlds.com/physics/4969222-physics-TL-DR-A-temperature-below-absolute-zero

The achievement of the Munich physicists could additionally be interesting for cosmology, since the thermodynamic behaviour of negative temperature exhibits parallels to so-called dark energy. Cosmologists postulate dark energy as the elusive force that accelerates the expansion of the universe, although the cosmos should in fact contract because of the gravitational attraction between all masses. There is a similar phenomenon in the atomic cloud in the Munich laboratory:

afreshstart77 · 61-69, M

Maybe some galaxies remember to turn their lights off when they go to bed?

shinyplasticlove · 51-55, M

Actually they are saying Dark Energy now.

Ferric67 · M

I agree

This comment is hidden. Show Comment

Add a comment...