/sci/ - Science & Math

>>12690334
Just watch the video you cunt. Why does it matter if she's a woman?

>>12690349
When women make videos, it's just their face.
When men make videos, it's usually a voice over with information.

If she wants to make money, she should make an OnlyFans.

>>12690334
I wonder what kind of dark matter she likes.

The paper absolutely does not disprove dark matter, because they don't even test dark matter models at all. The paper is testing MOND with an external field effect again MOND without an EFE.

https://arxiv.org/abs/2101.11644

This is just yet another MOND paper. MOND still has all the same problems that it always has. It failed to match the statistics of the cosmic microwave background, while dark matter models predicted the data nicely. MOND also falls apart in galaxy clusters, where it requires much more matter than is current known. MOND essentially needs dark matter, even before one tries to fix all the cosmological problems of MOND.

>>12690334
It's mommy Becky. She's our queen.

>>12690372
>peddles blatant clickbait bullshit
you should probably find a better queen then

>>12690355
>When women make videos, it's just their face.
>When men make videos, it's usually a voice over with information.
Source?

>>12690355
She was already on TV in the UK. The TY channel came later. I've no idea what channels you watch but all the guys show their face too.

>>12690334
tl;dr This observation isn't currently explained but it doesn't suddenly override the 99 others that agree with the existence of dark matter.

>>12690379
Never.

>>12690334
>Did she really disprove dark matter?
No

>>12690405
> This observation isn't currently explained
The paper doesn't actually demonstrate the effect cannot be explained by dark matter. The result in the paper is that their MOND fits to galaxy rotation curves are better with an extra parameter, than without. They claim this is evidence of an external field effect. All of this is entirely within the MOND framework, there is no clear prediction from dark matter models, dark matter fits are entirely different. You would have to look at dark matter simulations and fit MOND profiles to them, but the authors don't do that.

>>12690357
big black matter? is that what you're trying to pull off? retard?

>>12690446
What are you so upset about?

>>12690499
your shit humor

>>12690349
Sadly, majority of women in media are just stupid liberals trying to push agendas. Every time I play a video with a woman in front of the camera then end up talking about diversity and equality and all that stupidity.

>>12690371
So, they just used an inaccurate model to disprove predictions from more accurate models?

>>12690446
If she disproved dark matter, maybe she wants to be milky way bleached?

>>12690334
>Can someone summarize this video for me?
no tits

>>12690647
>So, they just used an inaccurate model to disprove predictions from more accurate models?
I don't know what you mean. When you test a model it doesn't necessarily tell you anything about other models. In this case there are no predictions from dark matter models which have been disproven by this.

>>12690380
How about those PBS videos though? Its that hand wavy guy who is constantly exaggerating his facial expressions and twitching his head around like a spastic. Irritating fuck. Unwatchable.

>>12690349
women are physically unable to not treat everything like a popularity contest, all information coming from them is false by default

>disprove dark matter
it would need to be proven first
all she did was point out how an equally made up idea can work just as well

>>12691507
MOND doesn't work equally well, far from it.

>>12691570
dont worry, im sure someone can invent some dark things to make it all fit. maybe some 'virtual dark things' that are defined by 'doing exactly what is required to make it fit'.

>>12691570
And dark matter doesn't exist. Just constantly pushing the same theory over and over and over and over again might as well be the same as religion.

Dark matter as a theory doesn't work because there is no proof or even glimmer of proof for dark matter. The only thing we actually know is that deep space objects like galaxies and galactic clusters act as though they have way more mass than we can actually observe.

There is a missing link, and its not fucking dark matter, cause if that shit was real we would 100% have observed it already considering how much of it "must exist" to make our current theories work.

Knock knock, truth is something like MOND or something totally different than dark matter is going to solve the problems for us.

>Why galaxies do not appear to obey the currently understood laws of physics.

Gentlemen. I present the "Naughty Galaxy" theory.

>>12691574
>maybe some 'virtual dark things' that are defined by 'doing exactly what is required to make it fit'.
Dark matter isn't defined like that. The models of dark matter are not infinitely flexible, they cannot fit any data. Cold Dark Matter is the standard model, which adds only a single extra parameter to standard cosmology (the mean density of it). From that single parameter simulations show all the emergent properties of dark matter, like NFW profiles and flat rotation curves.

>>12691580
>And dark matter doesn't exist.
It's funny you harp about religion while spouting this baseless assertion.
>Dark matter as a theory doesn't work because there is no proof or even glimmer of proof for dark matter.
Science doesn't deal in proof, only evidence. Dark matter models have made numerous successful predictions, such as the shape of the CMB powerspectrum.
> if that shit was real we would 100% have observed it already
Based on what assumed particle model? With what cross-section? You're talking bullshit.

>>12691667
That theory has been substantiated by the Theory of Smacky Bottom, which itself is backed by ample empirical evidence.. Why do you think so many Galaxies are red shifted? Yeah. Because they got a smacky bottom for being naughty Galaxies. The more naughty they are the more smacky bottom they get. Only our own Galaxy, being pure and virginal, has never been disciplined.

>>12690355
fucking hell man do you talk to people hahahahahahaha.

she could also just make money from her YouTube channel like what

>>12691680
>Dark matter models have made numerous successful predictions, such as the shape of the CMB powerspectrum.
First off they haven't predicted the CMBs spectrum, rather the model has fit all the measurements of it we have taken. Key point, we started measuring the CMB well before dark matter theories started (let alone CDM getting traction).

Yes there are measurements we can take, and we can see which models they fit into and which they don't. Evidence is not the same thing as fine tuning your theories to fit measured data.

Theres a reason why were even debating this in the first place, there are some pretty big holes in the various dark matter theories and none of them can actually seal the deal. Just like many of the predicted dark matter structures aren't observed, gravitation lensing does still happen in places where it shouldn't. Just because some things line up with dark matter, like measuring the CMB, that doesn't mean dark matter *has* to exist.

IMO dark matter is probably something that we already know about, be it some kind of cold dense plasma, neutrinos, or something else gay like gravitation wave constructive interference on a galactic scale. I think its really really really unlikely that theres some magic conditions of the vacuum state that allow special forms of matter to exist, let alone special forms of energy. And I think its way more likely that the big bang theory isn't 100% when it comes to the expansion of space.

>>12690334
I don't see why you guys hate her she's just explaining stuff.

>>12691818
>Key point, we started measuring the CMB well before dark matter theories started (let alone CDM getting traction).
Not the powerspectrum. There were no precise measurements of the powerspectrum until WMAP year 1 in 2003. This is well after CDM was established. Here is a figure of the state-of-the-art measurements in 1995. As you can see the prediction predates the measurements.
>gravitation lensing does still happen in places where it shouldn't
Lensing in the Bullet Cluster does not follow the distribution of normal matter. Most of the baryons are in the intra-cluster medium, which has been stripped out. CDM does not predict huge halos without galaxies, if that's what you're implying.
>IMO dark matter is probably something that we already know about, be it some kind of cold dense plasma, neutrinos, or something else gay like gravitation wave constructive interference on a galactic scale.
It being plasma would violate primordial nucleosynthesis and CMB constraints. Not to mention the fact that baryon only cosmology predicts a totally wrong distribution of matter in the modern universe. https://arxiv.org/abs/1112.1320
Cold plasma is also detectable through absorption against quasars.
Neutrinos aren't massive enough, and they're constrained by the CMB and matter power spectrum.
Gravitational waves also wouldn't work because it would be diluted too quickly with the expansion of the universe.
None of these would work without rewriting cosmology completely. It's totally illogical dismiss dark matter as "unlikely" while requiring a massive hand-wave for any of these to be remotely salvageable.

>>12690334
If a video, article, paper, etc is framed in the form 'does such and such disprove such and such?' 9 times in 10 the answer is no. As is the case here.

That said, there has been *some* progress towards developing alternatives to dark matter that actually work (the most recent that comes to mind is that a group managed to match the rotation curve of the Milky Way using estimates for visible matter only and a more complex GR metric that uses a more dust-like treatment of visible matter in the disk than the usual thick disk model). However, they have yet to be tested against some of the other predictions made by dark matter.

DM is still the king for now. If/when an alternative theory comes forth which satisfactorily matches all the same predictions, without the need for DM, then we can start treating it as a real debate.

>>12691941
>the most recent that comes to mind is that a group managed to match the rotation curve of the Milky Way using estimates for visible matter only and a more complex GR metric
In the paper they don't attempt to select the metric based on the observed matter distribution, at all. The parameters they fit in their metric are in terms of the rotation curve, not physical variables like the total mass. So they do not bother to test whether or not the mass distribution implied by their imposed metric is even remotely plausible.
And their model is obviously oversimplified, there's no bulge. They're only really fitting a tiny bit of the rotation curve where it's flat.

>>12691979
I'm not sure we're thinking of the same paper, what's that figure from?

>>12692038
It's the rotation curve of the Milky Way. The paper you're referring to only fits a small section probed by GAIA data.

>>12691979
>those error bars for the region where dark matter is needed
jesus they might as well say 'we have no fucking idea what's going on out there'

>>12692157
That wasn't the only data which existed at the time, there were also measurements using stars.

>>12691818
Is it really that far fetched that there's types of matter that exists that doesn't interact electromagnetically?

I'm wondering if there is an type of particle that doesn't interact gravitationally. Is there any theory that predicts that existing?

>>12690334
>Don't want to actually watch the video because she's a woman.
Are you jealous, sweetie, because you know you'll never be a real woman, no matter how much surgery you get, pills you take, or clothes you buy?