Submitted by taracus t3_ygfptx in askscience
exscape t1_iu9n8nz wrote
Reply to comment by andreasbeer1981 in Is dark matter orbiting galaxies with the same speed as normal matter? by taracus
Not true; if it were, why would so many different teams of scientists spend a ton of money and effort on building dark matter detectors (that aren't based on gravitational detection)?
Dark means it rarely or weakly (not necessarily never, how could we prove such a negative definitely?) interacts electromagnetically.
Nieshtze t1_iua3g98 wrote
And they haven't found a single piece of direct evidence for a massive particle yet, only neutrinos. Are there good reasons to believe that they have a non-zero interaction with electromagnetic field?
Aseyhe t1_iua4hmd wrote
Not necessarily electromagnetic, but we think dark matter should have some nongravitational interaction with ordinary matter in order to be created in the first place. Although, purely gravitational production is also possible...
andreasbeer1981 t1_iu9upff wrote
"Dark matter is called "dark" because it does not appear to interact with the electromagnetic field, which means it does not absorb, reflect, or emit electromagnetic radiation and is, therefore, difficult to detect."
exscape t1_iu9vyka wrote
> does not appear
That matches what I said.
And regardless, EM and gravity aren't the only forces in existence. There's no proof it ONLY interacts gravitationally as you said.
andreasbeer1981 t1_iuadk1d wrote
well, there is no proof that dark matter even exists. this is why it makes sense to make all kinds of experiments to find out more.
CrashCalamity t1_iuc7p4y wrote
Consider: Dark matter is something of a "placeholder name" as it pertains to a theory to explain certain anomalous (yet repeatably measureable) results in astrophysics. Something is causing it, but we need to figure out what and how.
Viewing a single comment thread. View all comments