Dark matter is bullshit right? I mean, there's obviously

Dark energy is bullshit. Dark matter is just matter which is not illuminated by light, although the exact amount is debatable.

>>8727086
You should read a bit about MOND, or about Erik Verlinde's emergent gravity theory. It totally ditches dark matter.

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>>8727109
this
erik verlinde btfo dark matter

>>8727086

What is more likely
1 OP is a brainlet that doesn't know what he's talking about
2 Thousands of top scientists are brainlet who don't know what they are talking about

People claim there is nothing between the atoms in space and that is is all empty.

There has to be some thing holding space apart.

Matter is merely a float in a sea of a yet to be identified medium.

>>8727096
Except it's not. Dark energy was bullshit but there was that one experiment which supported the existence of dark energy: that the universe is accelerating its expansion due to the presence of a cosmological constant and that this can only happen if dark energy has a repulsive gravity effect.

>>8727164
>that the universe is accelerating its expansion due to the presence of a cosmological constant and that this can only happen if dark energy has a repulsive gravity effect.

or
>diffusion
Matter is merely a float in a sea of a yet to be identified medium.

>>8727086
Non-astronomer here.

In what ways has dark matter been detected? From what little I know, it stems from the fact that the amount of mass in the galaxy/universe/etc is different from the amount of mass of objects which we can detect due to electromagnetic radiation. In fact, "dark matter" supposedly makes up the bulk of the mass in the universe. Have we detected dark matter within, say, our own solar system?

If not, then isn't it possible that the discrepancy which gives us "dark matter" is merely made up of regular stars and other objects that give off radiation, but which are wholly enclosed in Dyson Spheres or similar devices built by advanced alien civilizations? After all, a sufficiently advanced intelligence species could make structures complete enough that (almost) no waste radiation would escape that could be turned into energy.

>>8727170
>diffusion
You would be correct if galaxies and stars were spreading out to more empty spaces. Except they're not. There's a pattern. You should read the paper.

Dark matter is a mathematical canard!

There is evidence of the superfluid dark matter every time a double slit experiment is performed, it's what waves.

>>8727199
I think technically it could, but it seems highly improbable that even though we've never detected any real indication to other intelligent civilizations (not even radio signals or something), there's still enough of them out there to build Dyson spheres around so much matter.
Also, the manner in which dark matter seems to be distributed throughout the universe doesn't seem to match your hypothesis - wouldn't aliens rather have most of their Dyson spheres at about one place?

>>8728460
Personally I don't think we should make any assumptions as to how intelligent alien life would behave.

But my real question is: is there evidence of the existence of dark matter on a smaller scale than galactic?

I'm picturing it like this. Suppose you had a truckload of sand, and by weighing it you know that half of its volume is "heavy sand" that looks identical to normal sand, but which is much heavier. To measure the heavy sand up close, you'd need a small quantity that you could fit under a microscope.

Similarly, to learn more about dark matter, we'd need to find a fairly precise location of some which is close enough that we can observe the area with a probe or something. That is, we need to say "X star system contains dark matter" rather than "Y galaxy contains dark matter."

>>8728460
>it seems highly improbable that even though we've never detected any real indication to other intelligent civilizations (not even radio signals or something)
How many thousands or millions of years would it take those radio waves to reach us from the distant spokes of the galaxy? Or, what if they've been dead so long, the waves have come and gone from our system long before we had a means of detecting them? Before humans were even the top dogs on the planet?

>>8727152
Both

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>>8727199
>but which are wholly enclosed in Dyson Spheres or similar devices built by advanced alien civilizations?
dark matter only interacts via gravity. It does not interact with the electromagnetic force. This is why it's called dark. Pic related, the blue is mass based on gravitational lensing, the pink is mass based on light. When the two galaxies collided, the regular matter was affected by friction, the dark matter just passed right through.

>most of the mass of the universe is impermeable, invisible and immeasurable, OR gravity is much stranger than astrophysicists think?
Gravity just being stronger doesn't work. It does not explain the Bullet Cluster where most of the normal matter is between the peaks in the lensing. Any simply radial model also cannot explain it. No it is not simply a matter of making gravity stronger, any modified gravity has to be very ugly to explain observations and to date none of those attempts can go toe-to-toe with dark matter. Secondly no one is claiming dark matter is immeasurable, it is undetected not undetectable.

Just because you're completely ignorant of a topic doesn't mean everyone else is an idiot.

>>8727164
There are now multiple lines of evidence supporting dark energy from supernovae, baryon acoustic oscillations and the ISW effect. Dark energy wasn't really a term used before the first experiments were done. It wasn't bullshit either, it was supported by large scale clustering.

>>8727199
That's ruled out by microlensing, primordial nucleosythesis and the Cosmic Microwave Background powerspectrum. Microlensing was used to rule out MACHOs like black holes, waiting for the dark objects to gravitationally lens background stars. Big band nucleosynthesis uses the abundances of light elements that formed when the universe was minutes old to constrain how much matter was there, all dark matter as normal matter is not consistent. Lastly the CMB powerspectrum shows that when the universe was 300,000 years old dark matter was already dark, long before any stars or life formed.

>>8727109
MOND doesn't explain galaxy clusters and it doesn't explain cosmology, Verlinde hasn't done cosmology and his static models fail to explain situations like the Bullet Cluster. Until he actually produces a model that lives up to is claims dark matter is safe.

>>8727086
Who fucking cares. Physics is a model, so it doesn't matter as long as it makes accurate predictions.

>>8729223
Not necessarily. You're forgetting about the possibility of dark matter being MACHOs like primordial black holes.

>>8729199
Again, this is technically possible, but seems improbable in comparison to other explanations.

>>8729468
I have to say, it's nice to read such a well-educated comment (a rare sight on /sci/).