/sci/ - Science & Math

>>6700993

I think dark matter is just a word for that which is not really well understood but poses a problem to cosmological theories. I could be out of my ass here, took cosmology 1 time, got a B.

>>6700993
>except apparently anywhere near us?
this is false. Only /sci/ believes this. Dark matter is abundant, also in the solar system.

Also
> hurr durr DM is illogical we must go back to the roots of science
is officially a stale meme. If you care so much, get a degree and publish about it.

>>6701027
I didn't say go back to the roots of science, maybe just quit blowing funding money on a goose chase until other subfields start to illuminate what's going on

>>6701027
This. At this point science isn't to be debated or questioned, it is to be followed by the non-scholarly. Even the scholarly need to toe the line, dark matter is the truth. Accept it. If you question it you just don't know what you're talking about.

>>6701037
It's not science unless you have experimental evidence

>>6701040
You shouldn't be allowed to question science unless you have a degree and publish about a topic. That maligns science more than this "hurr durr you have to have evidence". Quit trying to disprove DM and just accept it on faith. Scientists that have studied this know more than you.

>>6701046
I have a degree and publish about a topic. Just not this topic. After all the seminars and all the classes nobody presented jack shit for evidence of dark matter other than the speed of galaxies spinning. I'm asking for an explanation, not for you to keep smelling your own farts.

>>6701046
how come this thread is finally good? God, yes. We have a minimum of three threads per day on this DM shit.

>>6701057
The evidence is theoretical. Cosmologists know what the fuck they are doing, but almost nobody else does.

Theoretical evidence is what it is. It's not crazy at all. In the past, theories have been thought insane for years until proven correct, so what can you say?

A shit load of people agree on a bunch of stuff regarding dark matter. I, a physicists in nothing to do with dark matter, have to simply concede that they may have a point. Then I go on my marry way, doing my shit, fully respecting their position. What else can I/we do?

>>6701057
well, with our current scientific method, if a theory introduces some unobservable phenomena (dark matter) it must predict some novel phenomena (expansion rates, or whatever, i`m not a real scientist)
because the theory accounted for more than the previous while explaining something, it is best to take it as truth until something explains it better... or take an instrumentalist approach and just use the model without accepting its truth or whatever, who cares

>>6701061
Admit they haven't found it, take their funding, use it for something likely to give results and not reshuffle the bullshit theory.

There's no such thing as "theoretical evidence"

>>6701065
I do not think that dark matter is known to be unobservable. There are some candidates (i guess) being looked at.

>>6701057
you haven't asked for clarification, you stated disbelief.

/sci/ is not the place to discuss science. Publications are. /sci/ is a place for sharing information. The information by the experts of the field is correct. The information by popsci and edgy teens is mostly pure fantasy.

You don't see evolution vs creation threads, do you? It's because there is no debate in the scientific community, only consensus. The same should happen with dark matter.

>>6701068
Likely to give results though...I have no idea what that means. I do solid state physics - very "tangible" stuff. But likely to give results doesn't exists. Tons of ideas fall on their face.

It is a totally different field. But as far as I can tell and have seen, cosmologists have worked up a hell of a case for DM, so DM research IS likely to give results, according to experts.

>>6701071
Publications aren't discussions.

>Sci is a place for sharing information
>sharing information does not equate to a discussion
>the supposed information you haven't presented at all even in a passive way is correct
>anything i've said is popsci or edgy

you're a retard

>>6701076
I'm pretty sure you're the retard here. The guy's pretty much stating that anyone that disagrees with him is a retard, and he seems to be a a pretty big expert, probably has a whole DEGREE and PUBLICATIONS about retardation. You shouldn't question his diagnosis of your retardation.

>>6700993
Here's a good example of a piece of the puzzle. I work in the same room as people looking for these things. Not sure what they are, but they are.

http://en.wikipedia.org/wiki/Axion

>>6700993

paper: http://arxiv.org/pdf/1403.5676.pdf

None of this is nilly willy, waste funding bla bla. That's crazy talk. Physics is a weird jigsaw puzzle that fits together kind crappily, but there is nothing "guesswork" about DM. Case clizzled.

>believe in dark matter
There is no belief, it's there. Now, what exactly it is is a whole different matter.

>>6701083
It's never clizzled.

Even if they match the signal from the Galactic Halo to axions, that wouldn't follow to a more general scale. The paper you cited extrapolates beyond the identification to provide models for calculations, it makes no effort to even highlight the possibility that dark matter is composed of axions.

Meanwhile several WIMP experiments have eaten billions of dollars while barely even putting limits on the rest mass.


It's not that PhDs or tenure make these people brilliant and hence automatically correct, they're taking leaps of faith. But so far their leaps of faith have been fruitless to make the critical junction and in some cases unnecessarily costly.

>>6700993
It's just that no other hypothesis better fits the data at this time, especially after the Bullet Cluster observations. If somebody can come up with a modification of gravity that works better, all the power to them.

>>6701105
>It's never clizzled.
Lol true.

>>6701108
cataclyzzled?

>>6701105
There is unseen mass in space. There are many theories regarding what this unseen mass is. Experiments and observation with the intention of finding a possible candidate is not a waste, even if it takes years and years to exhaust all the possibilities you're still learning SOMETHING.

>>6700993
if it didn't exist- how could it post a comment?

>>6701107

>>6701107

Exactly, so why don't they quit funding all these multibillion dollar experiments and put them into other unanswered physical questions that are more likely to produce results. They had their chance and it didn't pan out. The whole attitude pervading this thread that IT MUST BE and the inflated number of faculty and popsci surrounding "dark matter" keeps feeding research that can't even put a better limit on its mass.

>>6701113
maybe, though that's not guaranteed if you come up with nothing and can't put a limit on the mass. The amount you learn for the amount you spend isn't work re appropriating funds and waiting for a more plausible theoretical development or experimental approach that's widely applauded.

>>6700993
Photons are their own anti-particle?
-source http://en.wikipedia.org/wiki/Particle_physics

Particle-antiparticle pairs can annihilate each other, producing photons;
- http://en.wikipedia.org/wiki/Antiparticle

>>6701046

>you shouldn't be allowed to question science unless ...

I can't believe somebody this stupid could figure out how to turn on a computer and read the words on the screen.

>>6701061

>the evidence is theoretical

What the fuck does this even mean? Holy shit is what darkmatterfaggots actually believe? No wonder nobody takes you fucks seriously.

Face it, dark matter a shit. MOND a best.

Since all particles Annihilate to photons, everything is made of photons? ^^

I think i'm going to give up teaching /sci/ though... it's easier to figure out how things work xD

>>6701140

General relativity was theoretical for a while. Until we saw mercury's precession. Relax cowboy.

>>6701130

kay?

Except bosons don't have antiparticles

>>6701152
it says own on the chart, not none?

>>6700993
It's an effort to explain why observations don't match theory. The biggest issue is there is that nobody knows what the fuck it is and it hasn't been observed.

The best we have to go off of is the fact that it makes simulations work well, but cop-out explanations that are shoehorned in to make models fit observations without any real evidence tend to be wrong in astronomy. See 'epicycles'.

>>6701163

that's a meaningless misnomer. But it's all irrelevant anyways

http://en.wikipedia.org/wiki/Dark_matter#Observational_evidence
Jesus fuck

>>6701152
That's false. For example, W^+- are antiparticles of eachother, but they're vector bosons. The discriminating quality is not spin, it's charge. Electrically charged particles correspond to complex fields (because C is the fundamental representation space of U(1)) and complex fields have antiparticles.

An example of a spin-0 boson with antiparticle is the Higgs multiplet before electroweak breaking; it is weak-hypercharged and thus is complex which means it has antiparticles.

>>6701201
>Nah man dark matter is bullshit faith religion lizard people conspiracy
>trust me I post on /sci

>>6701238

The argument is that it doesn't imply the mass is the source of the discrepancy, it's just a candidate theory

>>6700993
I wish this thread would make like dark matter and fucking. Not be...visible.

>>6701118
>Exactly, so why don't they quit funding all these multibillion dollar experiments and put them into other unanswered physical questions that are more likely to produce results.

Because who the fuck died and made you the president of science grants?

>>6701105
>several WIMP experiments have eaten billions of dollars
That's simply not true.

Dark matter is more or less known to exist. There exists a galaxy, NGC 4254, which was part of a cosmic collision with something of GIGANTIC mass (the size of a galaxy), but there is nothing nearby for it to have impacted. This is observational evidence of masses of dark matter in the universe.

>>6701140
>MOND a best.
You say that as someone completely ignorant of the field. MOND cannot explain the dynamics of galaxy clusters, not without dark matter anyway.

>Some shit spins around faster than you expected

No much more than that. It's clear you didn't do your reserch before starting this crusade. There is evidence in light element abundance, galaxy clusters, gravitational lensing and structure formation.

>so this implies that there's a bunch of heavy, invisible, non-interacting shit everywhere in every galaxy except apparently anywhere near us?
No. There is evidence for dark matter in the local stellar neighborhood and the evidence pointing to non-interacting (expect gravity) particles is extensive. It was not the first hypothesis

Nice strawman.