As far as I understand it, the way stars, planets, gas clouds and galaxies move wouldn't make sense with just the gravity of the visible objects. There needs to be so-far-undetectable (directly, at least) dark matter in the otherwise empty space? I don't really remember if it was understood to be a universally equal distribution, or if it is understood to be concentrated in blobs/clouds/noodles or whatever.

I don't really have a lot at stake riding on it, while it's interesting physics and to an extent I care about it, I don't really care enough to either ridicule, push for solid answers "NOW", hunt down frauds, etc.. Some people really care about that, I don't really take it that seriously. I don't think life should be a rat race where you're either immediately useful and correct, or cut off and dead. The scientific consensus seems to be that there isn't really a good alternative to dark matter. Was it string theory that tried? I might be misremembering, but as far as I've heard, that's basically dismissed and disproven regardless of whether it had anything to do with dark matter.

On a final note, is there any reason to expect that the giant deep Antarctic ice-telescope will be able to observe dark matter? Apparently it's supposed to be able to pick up on wavelenghts that we so far haven't had the chance to observe, iirc by triangulating rare flashes of light from neutrino collisions with particles in the extraordinarily clear ice.

[–] ThoughtGoblin@lemm.ee 2 points 1 year ago (2 children)

The scientific consensus seems to be that there isn’t really a good alternative to dark matter. Was it string theory that tried?

The alternative to dark matter is modified gravity/modified Newtonian dynamics. Neither of which have held up to scrutiny and have major flaws that would need to be worked out before being a legitimate competitor to dark matter. In every single permutation thought of today, these theories directly conflict with the reality we observe, while dark matter has been in happy agreement with new data.

that’s basically dismissed and disproven regardless of whether it had anything to do with dark matter.

String theory is not disproven and still remains the leading train of thought. It's just a very niche field and progress is hard/underfunded! But so far we've seen things like AdS/CFT correspondence and it's a more "elegant" solution than its competitors.

is there any reason to expect that the giant deep Antarctic ice-telescope will be able to observe dark matter?

Are you talking about the IceCube? If so, no, that's a neutrino telescope. Although, in general, the answer would also be no; dark matter does not interact with itself or with regular mass in any way other than through gravity. It's simply impossible to measure it directly - it must be done by measuring it's gravitational effect on other things.

And because of that very property dark matter's smallest observable structures are galactic in scale, so it's also rather hopeless to try to observe them locally with current technology.

[–] Comment105@lemm.ee 2 points 1 year ago

Thank you

[–] niflhiem@lemm.ee 0 points 1 year ago (1 children)

String theory in all it's permutations is still fundamentally untestable and had been since it's inception. I can't speak for academia (though I did watch a YouTube video that claimed to, and it ended up with this same conclusion, fwtw) but in scientific media string theory is more or less absent now. Early 2000s it was everywhere but the standard model kept plugging along without string theory, and now I only see it if I look for it specifically. It's not the leading train of thought and I doubt it ever really was - it was just popular in media. The standard model for quantum stuff and special relativity/general relativity for macro stuff is still the generally accepted view

[–] ThoughtGoblin@lemm.ee 1 points 1 year ago

If your view of string theory is through the lens of media, you aren't going to be up-to-date. String theory was and is the leading theory for quantum gravity, is actively worked on, and has only been supported in recent findings through quantum field theory.

But you're talking about a field with little funding, that requires some of the most brilliant mathematical minds who have specializations, and in which experimentation requires super technology to build particle accelerators the size of the moon. It's not a glamorous field and once the buzz of "theory of everything" wording died off, it was forgotten in media. Just like so many other topics before it.

The standard model for quantum stuff

The standard model doesn't handle quantum gravity, which is kind of important. Nor does it address a slew of other very real phenomenon (dark matter, for instance). It's not a theory of everything, just a good model. It's also something that can be derived from string theory. The two are not competing ideas.