Dark Matter and Dark Energy

Supposedly there is Dark Matter which bends light with its own gravity and is the reason galaxies don't fly apart and is also the reason for the superstructures we see.

Supposedly there is Dark Energy which is causing space itself to expand and the rate of this expansion to be accelerating.

But what if there is only one of these two, and it is an antigravitational force? What if it is pushing light instead of pulling light? That is, the inverse of what Dark Matter is thought to be? Has anyone done the math and shown that no, Dark Matter is definitely causing pulling-gravity and not pushing-gravity? Maybe it's in the spaces we think it's not and not in the spaces we think it is - that is, that our dark matter map is inverted.
Last edited on
Dark energy is a term that comes out of the derivation of Einstein's general relativity equations. You can see if you spend some (a lot of) time going through L. Susskind's wonderful lectures on Youtube of general relativity to see how this comes about. It is an energy inherent of space itself. Gravity describes the curvature of space-time. Dark energy does not describe its opposite. Also, dark energy is totally unrelated to dark matter. Dark matter does not appear anywhere in these field equations.

In fact, dark matter looks to be no different that ordinary matter. A great deal of heavier particles are allowed (generally required actually) for any version of the standard model of physics to be complete. Everyone is assuming that when the LHC ramps up high enough, we have a good chance of seeing creation of some of these dark matter particles. They are probably no different from ordinary matter, other than the fact that they do not interact electromagnetically. If dark matter is indeed just ordinary matter, which nearly all theoretical physicists believe it to be, there is no reason to suspect it to be anti-gravitational magic coming from an unknown material filling all voids.

Has anyone done the math and shown that no, Dark Matter is definitely causing pulling-gravity and not pushing-gravity?


So in short I think the answer is probably that no-one has done a bullet proof mathematical disproving of your conjecture, but, there is nothing in the maths at the moment to suggest such a theory to be true and plenty of maths suggesting (but not proving) it would not be true.



closed account (oGbjE3v7)
Wasn't there an observation a while ago that disproved dark matters existence where it was theorized to be ?
just to add, all dark matter really means is matter that doesn't emit light, and isn't readily detectable. it *could* just be huge gas clouds, but that theory has fallen out of favor. right now, scientists think it could be a WIMP (weakly interacting massive particle) or neutrinos.
The mass of the universe is big. And when you take every thing from planets to black holes and add up their mass it is not equivilent to the mass of the universe. So scientists came up of a theory of dark matter. Matter that sums up the rest of the mass. and Dark energy.... You know that the universe is expanding. It is sopposed to be compressing because of the planets and galaxies mass pulling them together. But scientists belive that there is a force that is pulling them apart expanding the universe.
my house mate is physicist I will get him to comment here some time this week
No one an argue that it wouldn't be irrefutable proof, one way or the other, if someone just went out there and gathered some of the stuff...

Of course, we can't, so why would we make assumptions?

Anyone got some irrefutable proof?

Yes, the conclusion of dark energy/matter was derived by logical conclusion, but somtimes logic can be flawed. For instance, what if there is no dark energy? What if the univers is expanding simply because the big bang sent all this matter flying outward?

How can we be so sure that dark matter exists? What if they are just a cluster of black holes that are no where near any source of matter (making them appear invisible, but showing the gravitational force)?

What if There is no dark matter, but just a bunch of dust blocking all the light, and making it appear dark as pitch? Certainly a cloud big enough to be a 'nebula' would take billions of years to coalesce.

My point is how do we know for sure that it is, in fact, dark matter, and absolutely can't be anything else?
Last edited on
What if the universe is expanding simply because the big bang sent all this matter flying outward?


You realize that would energy right? Besides, I've never seen a quantum or relativistic model of the universe without a prediction of dark energy.

How can we be so sure that dark matter exists? What if they are just a cluster of black holes that are no where near any source of matter (making them appear invisible, but showing the gravitational force)?


Well in that case, the dark matter would be the black holes. We know dark matter exists because we can measure its gravity. Something must cause that gravity and whatever is causing it is dark matter, whatever that dark matter turns out to be. It's only named dark matter because we are not yet sure what it is, so it gets the 'dark' (since it emits no light) name for now.


What if There is no dark matter, but just a bunch of dust blocking all the light, and making it appear dark as pitch?


What you are conjecturing here is dust that emits no light i.e. Dark matter. Your question should read, what if dark matter is just a bunch of dust that emits no light?


My point is how do we know for sure that it is, in fact, dark matter, and absolutely can't be anything else?


The reason it's called dark matter is because we don't know what it is. It's like, if there is a room with an item in it, and I've not seen in the room and someone asks me what is the room, I will say there is a thing in the room. They would not then turn around and ask me "how can you be sure it is a thing and not something else?"

In short dark matter:
-Has gravity
-Emits no light
-Is all over the place

That's all we know for sure.
For me, dark matter and dark energy (for what I've learnt) are from Eistein's theory of relativity. Dark energy and matter are in everywhere. See Hubble statistics. It's from news web site: http://hubblesite.org/newscenter/archive/releases/2012/10/full/
Mats' comments will explain you everything. See wikipedia page: http://en.wikipedia.org/wiki/Dark_matter. I have a two/tree years "wiki" of particles that I made, but I never considered to sell it (and I've cryptographed it, so nobody (except me) can read it). If I have time, I'll post some info.
Last edited on
The reason it's called dark matter is because we don't know what it is. It's like, if there is a room with an item in it, and I've not seen in the room and someone asks me what is the room, I will say there is a thing in the room. They would not then turn around and ask me "how can you be sure it is a thing and not something else?"

THANK YOU Mats! I have this discussion with so many people that can't even comprehend what you summed up perfectly in the first sentence here. The only change I would make to your analogy is that it is more like this: There is a room that may or may not have one or multiple things in it. We cannot look inside of this room yet. There is a noise coming from the room. We can identify specific attributes of the noise like it's volume, frequency, bass etc but we don't know if this noise is an attribute of the room or if it is being emitted from something(s) inside of the room. We don't know if the frequency we observe is from one object or if it is multiple object emitting the noise one after the other. We don't know if the bass we observe is due to the noise being emitted interacting with the geometry of the room. Heck, if you want to start introducing quantum theories into this analogy we can't tell if the noise is coming up from a heating vent inside of the room either.
Last edited on
My problem is that many science shows seem to be confidently pushing the idea that dark matter is a certain way.
THANK YOU Mats!


Thanks. :)

There is a room that may or may not have one or multiple things in it. We cannot look inside of this room yet. There is a noise coming from the room. We can identify specific attributes of the noise like it's volume, frequency, bass etc but we don't know if this noise is an attribute of the room or if it is being emitted from something(s) inside of the room. We don't know if the frequency we observe is from one object or if it is multiple object emitting the noise one after the other. We don't know if the bass we observe is due to the noise being emitted interacting with the geometry of the room. Heck, if you want to start introducing quantum theories into this analogy we can't tell if the noise is coming up from a heating vent inside of the room either.


Yeah pretty much man. These bizarre analogies are as close as you can get if you don't do the maths. I'd have to recommend if you're mathematically inclined to take a look at it some day too. It's truly mindblowing.

My problem is that many science shows seem to be confidently pushing the idea that dark matter is a certain way.


In all honesty, most leading physicists are confidently pushing the idea that dark matter is that certain way and it's filtering down, though in a simplified way. The physicists have their models, mathematics and experiments all backing them up so far. When the LHC switches back on in 2015, no-one would be surprised if dark matter was found, although, what every scientist is secretly hoping is as we keep racking the energy up, it will not be like all the evidence points towards. In that case, we would literally be almost back to zero on the entire dark matter front.
Last edited on
Topic archived. No new replies allowed.