Katie MackMar 3, 2023

‘The most common response I get when I talk about dark matter is: “isn’t this just something physicists made up to make the math work out?”
The answer to that might surprise you: yes! In fact, everything in physics is made up to make the math work out.’

My latest for BBC Science Focus:

https://www.sciencefocus.com/news/everything-physics-made-up/

Yes, everything in physics is completely made up – that’s the whole point

A physicist's task is to constantly create equations that keep up with our observations of physical phenomena.

BBC Science Focus Magazine
Show threadTony Fisk
@AstroKatie it just gets a little frustrating when there's nothing (yet) to back the math up.
Mar 3, 2023 at 11:43pmWeb
Show threadKatie MackMar 3, 2023
@arfisk Not sure what you mean. Back it up with what?
Show threadTony FiskMar 4, 2023
@AstroKatie In relation to 'dark matter', corroborative evidence that distinguishes WIMPS from MACHOS. However neat the maths that describes them is, I'm unaware of any direct evidence for axions etc.
Sure, they explain what we observe, but can anything else? (eg normal unseen matter, or MOND)
Show threadclacke: exhausted pixie dream boy 🇸🇪🇭🇰💙💛Mar 4, 2023
@arfisk I think you are making the point of @AstroKatie 's article.

The label "dark matter" might be a bad name because it evokes the idea of something like WIMPs. But all dark matter is is a bunch of equations that fit with observations.

There isn't enough detail yet to allow philosophers, much less the general public, to say what dark matter "really is".
Show threadF.U. 🅭…Mar 8, 2023
@arfisk @AstroKatie
MACHOs and MOND are nearly ruled out, but BTW physicists don't like to mention that the W in WIMPs might be wrong too.
Baryons interact with 4 known forces.
Leptons: 3 (no strong).
Neutrinos: 2 (no EM).
It's entirely possible dark matter has NO weak interaction, which would make them literally undetectable except in the way we already have (observing their gravitational effect on "regular" matter).
Show threadBigsmiffyMar 3, 2023

@arfisk @AstroKatie

Apart from observation?

Just like Newtonian gravity