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Dark matter matters by Clyde Tombaugh - Wed, 09 Nov 2016 03:09:08 EST ID:zHoQtF+M No.56645 Ignore Report Quick Reply
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There's 10 times more matter in the universe than we thought:
http://blogs.discovermagazine.com/d-brief/2016/10/13/the-universe-is-20-times-more-vast-than-we-thought/#.WCLTmjU2thE

A natural law for rotating galaxies:
http://www.physicscentral.com/buzz/blog/index.cfm?postid=5308541299875990673

And finally, matter causes entropy displacement which accounts for the dark matter effect:
https://arxiv.org/abs/1611.02269

TL;DR, we found our missing mass, we can see that rotation speed varies with the amount of visible matter, and with a better understanding of gravity, the whole concept and purpose of dark matter is bunk.
>>
Fred Whipple - Wed, 09 Nov 2016 18:43:00 EST ID:rszf0FN0 No.56647 Ignore Report Quick Reply
Thank god finally people with a sense of reason. Dark matter was the biggest crock of shit to ever come out of modern physics. I remember arguing these points hypothetically on this board and being laughed down because it wasn't LCDM which of course is the only truth. Maybe now people will listen.
>>
Riccardo Giacconi - Thu, 10 Nov 2016 23:36:41 EST ID:OXINl/7g No.56648 Ignore Report Quick Reply
>>56645
>>56647
Except that extra matter they found doesn't necessarily reside within galaxies we've already detected, because the universe is actually BIGGER than we thought, not just stuffed with more stuff. Dark Matter has been indirectly observed through gravitational lensing, and within theorized parameters.
http://arstechnica.com/science/2012/07/dark-matter-is-the-thread-connecting-galaxy-clusters/
>>
George Gamow - Fri, 11 Nov 2016 03:10:29 EST ID:M/g1akbS No.56649 Ignore Report Quick Reply
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>>56645
First link you posted..lets go to the source and read the abstract, rather than the media filter version.
https://arxiv.org/pdf/1607.03909v2.pdf
Which makes me agree with Riccardo Giacconi here.

Second article, lets go to the source again:
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.117.201101
they state:
>We report a correlation between the radial acceleration traced by rotation curves and that predicted by the observed distribution of baryons.
Neat, what do they conclude?
>The correlation persists even when dark matter dominates.
>Consequently, the dark matter contribution is fully specified by that of the baryons.
Meaning that dark matter contributions are associated with baryonic matter, which could prove a correlation between the two.
Doesn't discount DM. Theyre actually comparing mapped distrobutons with that of baryonic matter.


Third article, we read, towards the end of their abstract:
>The emergent laws of gravity contain an additional `dark' gravitational force describing the `elastic' response due to the entropy displacement. We derive an estimate of the strength of this extra force in terms of the baryonic mass,
>Newton's constant and the Hubble acceleration scale a_0 =cH_0, and provide evidence for the fact that this additional `dark gravity~force' explains the observed phenomena in galaxies and clusters currently attributed to dark matter.
Their conclusions seem to support additional 'dark' forces, not a lack of dark matter via entropy displacement.

I dunno mate, its real late - I just got off work. It seems to me that these articles are not discounting DM, but finding interesting ways its contributing to recently observed cosmological phenomenon
>>
William Hartmann - Fri, 11 Nov 2016 03:56:29 EST ID:rszf0FN0 No.56650 Ignore Report Quick Reply
>>56649
You're equating a 'dark force' with 'dark matter' as concepts and their totally different. A 'dark force' would simply be any parameter about physical mechanics which we are only able to infer from it's effect and not directly. It supposes that there is a subtle law of physics which is lacking from our theory. LCDM is totally the opposite. It assumes that our laws of physics must be correct, so the only way to account for the difference is to assume that what is lacking is actually a real substance out there in the world, hence 'dark matter & energy.' So the one is saying that we are lacking a complete theory, while the other is saying that there is definitely something out there even though we can't see it and have no other evidence of its existence than that if we didn't have it we would have to assume our laws of physics are wrong. I think any reasonable person can see which one of those two approaches is koo-koo.
>>
Hannes Alven - Sat, 12 Nov 2016 00:48:41 EST ID:M/g1akbS No.56651 Ignore Report Quick Reply
>>56650
>I think any reasonable person can see which one of those two approaches is koo-koo.
Well, here is your faltering. Both approaches are subject to a whole range of mathematical analysis and correlation between seemingly unrelated data-points. It is a testament to science that both theories can equate to similar conclusions. Neither is 'koo-koo'; both have proven formulae that are well above our collective level of knowledge. It is merely the conclusions of said data we argue.

>A 'dark force' would simply be any parameter about physical mechanics which we are only able to infer from it's effect and not directly.
So, dark forces. Yes, they exist, you agree. Dark matter is included - which also helps explain dark energy.

However, as OP states:
>the whole concept and purpose of dark matter is bunk
This is a dramatization - it isnt bunk - it is a well measured effect that has a plethora more papers written about it than any other plausible theory. Certainly, the only theory with more papers written about it trying to disprove it is likely General Relativity.

>It assumes that our laws of physics must be correct
Generally, yes, our theories have matched up pretty well with observational phenomenon.

Moreover - And I hate quoting from wikipedia's LCDM page- there is this:
>It is frequently referred to as the standard model of Big Bang cosmology because it is the simplest model that provides a reasonably good account of the following properties of the cosmos:
>-the existence and structure of the cosmic microwave background
>-the large-scale structure in the distribution of galaxies
>-the abundances of hydrogen (including deuterium), helium, and lithium
>-the accelerating expansion of the universe observed in the light from distant galaxies and supernovae

The OP's articles nitpick what holes they find, and assume that these holes mean DM is bunk. Yes, the scientific articles behind them are neat, but we're untrained [for the most part] observers, trying to draw conclusions off of incomplete sci-media articles.

Moreover, I am not assuming anything, I am merely re-stating what these source articles stated without a media filter on it....
>>
Henrietta Levitt - Sat, 12 Nov 2016 02:51:19 EST ID:rszf0FN0 No.56652 Ignore Report Quick Reply
>>56651
Ugh I'm too drunk for this right now but I can't ignore your post.
Your argument is based on the assumption that both of us neither know what they're really talking about or understand the theoretical underpinnings of why the theory is the way it is or what this new data reflects. That's incorrect, because I do, this stuff is not 'above [my] collective level of knowledge.'
>>dark forces. Yes, they exist, you agree.
Uh, no? If a dark force exists, it is an aspect of fundamental mechanics that can only be observed in the very large scale motion of galaxies (that propogation of inertia they talk about in the papers) whereas a dark force would be an actual physical tangible thing that exists. That's what I said in the last post. Matter and energy aren't forces, they're substances. Forces aren't tangible things, they are (or are expressed) mathematical relationships between fundamental principles. Dark substances exist 'in a place' whereas a dark force exists everywhere.

>>everything else you said is just an appeal to authority
What else do I need to say? Appeals to authority have no place in science. There have been tons of phenomena that have had reams of papers written about them to turn out to be pure bunk. And indeed what these papers are proposing is that the discrepancy between our model and our reality should be found exactly where we do find it, in the motion of very large structures. So I don't see where you get off denying the argument these papers are putting forth, especially when you openly admit you don't really know what they're talking about.
>>
Henrietta Levitt - Sat, 12 Nov 2016 02:52:58 EST ID:rszf0FN0 No.56653 Ignore Report Quick Reply
>>56652
Argh, I meant to say 'a dark substance would be an actual tangible thing that exists' instead of saying dark force twice. I'm too drunk.
>>
Cecelia Payne-Gaposchkin - Sat, 26 Nov 2016 21:28:21 EST ID:by9sGz0i No.56684 Ignore Report Quick Reply
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>>56645
>There's 10 times more matter in the universe than we though
That's not what the paper says. If you read it what they conclude in the paper is that if you extrapolate galaxy luminosity functions you get 10 times more galaxies than would be detected in a full sky Hubble Ultra Deep Field. This was widely misreported as calming there were 10 times more galaxies than previously thought, however no one thought the HUDF was all galaxies. Lastly this all has nothing to do with the matter content of the universe, that is determined from cosmological tests not counting galaxies.

>A natural law for rotating galaxies
Which dark matter simulations match despite the fact these simulations were run before the paper was published.

https://arxiv.org/abs/1610.07663

>And finally, matter causes entropy displacement which accounts for the dark matter effect

Some dark matter effects, not many important ones. Verlinde's presented model has had a lot of media coverage but the paper doesn't hold up to the hype. In the paper only static solutions are derived, the two solutions are a disk galaxy and a relaxed galaxy cluster. What about dynamic situations like the formation of cosmic structure of colliding galaxy clusters like the Bullet Cluster? Not explained, his static solution would fail to explain observations if applied to the Bullet Clusterl. The model presented in the paper doesn't explain the observations that we have today, it doesn't really go further than previous modified gravities. Verlinde's model is an untested hypothesis and it cannot replace dark matter as it is now. Until it can match observations of the Cosmic Microwave Background and Bullet Cluster and BAO results it's not fit to replace standard cosmology.

>>56650
>I think any reasonable person can see which one of those two approaches is koo-koo.
And yet when it came down to the problem of momentum conservation in Beta decay it turned out that there was a new particle and the laws of physics were just fine. If we followed your logic neutrinos never would have been discovered. What you describe here is personal bias, there is no sound logic to discarding an entire avenue of hypotheses.

>>56652
>>everything else you said is just an appeal to authority
What total and complete bullshit. Pointing to the observational expedience is not an appeal to authority, that is an appeal to empirical science.

>There have been tons of phenomena that have had reams of papers written about them to turn out to be pure bunk.
That doesn't give you the right to ignore evidence that doesn't suit your ideas. If you believe some observations are flawed prove it, until then any cosmology will have to meet those tests.
>>
Thomas Gold - Sat, 03 Dec 2016 04:55:56 EST ID:HIn7gwXH No.56706 Ignore Report Quick Reply
https://www.quantamagazine.org/20161129-verlinde-gravity-dark-matter/
>>
Johann Bode - Wed, 21 Dec 2016 19:42:19 EST ID:SD/dK0pb No.56733 Ignore Report Quick Reply
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i happen to be an expert on Dark Forces
>>
Schepperschop - Fri, 23 Dec 2016 12:59:12 EST ID:q7dt2mlj No.56735 Ignore Report Quick Reply
Doesnt matter2me.
>>
James Elliott - Mon, 26 Dec 2016 23:00:11 EST ID:d7Fd77VL No.56738 Ignore Report Quick Reply
>>56735
th3nYdidUpost?
>>
Edwin Salpeter - Thu, 29 Dec 2016 01:29:49 EST ID:10QI3ruX No.56740 Ignore Report Quick Reply
>>56733
Its kind of funny how the problems with science in most of the star wars universe can be waved off with the resounding explanation of the force.
>not sure how this works
>the force makes it work
Its like the ultimate writters tool to get out of things not making sense science wise ever.
>>
Heinrich Olbers - Thu, 29 Dec 2016 06:32:40 EST ID:YHjXylC8 No.56741 Ignore Report Quick Reply
>>56740
Every age of pop sci-fi had some kind of magic that made the things work, first it was lightning, then it was radiation, then it was biology, today it's nanobots, tomorrow it will be terrible understandings of quantum phenomena.
>>
William Huggins - Thu, 29 Dec 2016 17:51:00 EST ID:xbVB8ilz No.56742 Ignore Report Quick Reply
>>56741
This electro neutrino drive will allow us entangle entire planets!
>>
Cecelia Payne-Gaposchkin - Tue, 03 Jan 2017 11:49:28 EST ID:lAm+gnu+ No.56746 Ignore Report Quick Reply
>>56738

Doesn't matterm8
>>
Maximilian Wolf - Sat, 07 Jan 2017 15:09:35 EST ID:S3Ee8l28 No.56748 Ignore Report Quick Reply
>>56647
Yeah people always shut down when I suggest that 'laws' may be fundamentally flawed because we've been observing the universe from an infinitesimally tiny window of time/space.
Me: What if gravity is growing stronger and big crunch?
Everyone: kys faggit wut a plebian fukwit hurr durr what if u wasnt born??!
The only axiom I accept 100% is Descartes - Cogito ergo sum.
>>
Jacob Kapteyn - Sun, 08 Jan 2017 01:48:53 EST ID:M/g1akbS No.56749 Ignore Report Quick Reply
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>>56748
Except we can point out to you several cohesive, well thought out arguments with several referenced publications; namely:
>>56649
>>56652
>>56684

Sounds like you're just mad that someone actually took time to read the arXiv abstracts and refute things.
>Everyone: kys faggit wut a plebian fukwit hurr durr what if u wasnt born??!
Did you even read the thread?

Long story short...Calling dark matter "a crock of shit" with no evidence is bound to get great responses on this board. I mean, really? Get off your high horse.

And another thing:
>we've been observing the universe from an infinitesimally tiny window of time/space.
Redshift and CMB would like to talk with you.
>>
Anders Angstrom - Wed, 11 Jan 2017 11:04:37 EST ID:ZZZCwSAu No.56752 Ignore Report Quick Reply
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>>56749
The very idea that anyone could question so unshakeable a truth as the phlogiston theory is unthinkable! These knaves best read the latest paper by Johann Becher and check thyself before ye wreck thyself.
The very temerity to suggest that a physical phenomena could have a cause beyond the scope and verity of our instruments and the mighty dint of our mathematical understanding! It's nigh unto BLASPHEMOUS!
>>
Tadashi Nakajima - Sat, 11 Feb 2017 12:30:19 EST ID:+G8ef2Iy No.56783 Ignore Report Quick Reply
>>56749
Yo, I agree with most of what you've said man but
>we've been observing the universe from an infinitesimally tiny window of time/space.
>Redshift and CMB would like to talk with you.

We still only see snapshots of those moments. Even if we're seeing snapshots from locations all over the observable universe, each of those is only set of moments that appear to be occurring now to us. Considering they've all been doing they're own thing relative to us over the massive distances they have, we're necessarily only seeing a very small window of what's actually been going on locally in each location. Even if we can see energy readings from close to the beginning of the universe like with the CMB, it's still only a tiny part of that. I don't even get what redshift has to do with us seeing more than small fraction of what's been going on. I know what it is as a phenomenon and how it affects what we can see, but it doesn't even make sense as part of your argument.

So, the dude at least had a point there. Not in the larger scheme of his arguments about dark matter, but the statement is factual is what I'm saying. It seems like you're trying to make a point because he's proven himself not to know what he's talking about to such a degree that you just wanted to disagree with everything he said whether it had merit or not.
>>
Giovanni Cassini - Sun, 12 Feb 2017 19:32:09 EST ID:e0oA2mYt No.56784 Ignore Report Quick Reply
>>56748
>Yeah people always shut down when I suggest that 'laws' may be fundamentally flawed because we've been observing the universe from an infinitesimally tiny window of time/space.

You've obviously never spoken to an actual scientist about this then. If some change is so subtle that it cannot possibly be tested in observation then it probably didn't have much impact on the formation of the universe up until this point. Yes the standard cosmological model would be incomplete but it doesn't mean it's description of the the universe today and it's history would be wrong. If it's not flawed in any way we can test it can hardly be called "fundamentally flawed".

It is always true that new evidence tomorrow could unseat any theory in empirical science, that isn't criticism of any particular theory. You're literally criticising theory because it is scientific.
>>
Daniel Kirkwood - Tue, 14 Feb 2017 03:27:41 EST ID:M/g1akbS No.56785 Ignore Report Quick Reply
>>56783
>Yo, I agree with most of what you've said man but...
Yeah, I was mad in that last part, excuse the flippancy. You raise a valid point about the snapshots-in-time. The only caveat is that we can observe [usually] the same type of effect in several locations in the sky. This can give us a good correlation to the observed effect being distributed evenly in the universe.


It is my sincere wish, however, that we stop poking logic holes in each others' theories [see >>56645 and >>56748 ], and start referencing actual science articles to back up assertions. OP did a good job supplying articles to chew on, followed by good counterpoints by others. Lets get more of that.
>>
Johann Bode - Fri, 17 Feb 2017 23:29:59 EST ID:yzfSDg8q No.56789 Ignore Report Quick Reply
>>56785
Well I wouldn't call it a snapshot in time, but rather a snapshot in perception. Our view of the universe is always changing, so the picture we have right now is only a snapshot, regardless of how much time it represents. You can say the current laws of physics are immutable and timeless, but these laws have only been accepted as a general concept of the universe for a couple hundred years. Previous theories of the universe such as Platonic Idealism were also based on observation, and were of course supposed to be immutable. They lasted for thousands of years.
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Bruon Rossi - Mon, 27 Feb 2017 13:16:01 EST ID:FoZr+PSB No.56843 Ignore Report Quick Reply
http://cosmos.nautil.us/short/144/the-physicist-who-denies-that-dark-matter-exists
>Dark matter is our generation's ether
>>
George Herbig - Tue, 28 Feb 2017 21:08:22 EST ID:7jcVAyVz No.56845 Ignore Report Quick Reply
>>56843
If a0 is equal to the speed of light divided by the radius of the universe, since the radius of the universe is equivalent to the time since the big bang and thus always increasing, presumably this also means the acceleration constant decreases overtime, which means the same amount of force creates more acceleration, right? (thus accelerating expansion) is this an intentional aspect of MOND? Why didn't they predict an accelerating universe beforehand if so?
>>
John Bahcall - Wed, 01 Mar 2017 19:11:28 EST ID:e0oA2mYt No.56846 Ignore Report Quick Reply
>>56843
Wrote a big response but the board swallowed it twice. Milgrom is talking shit, MOND doesn't bridge anything with the largest scales. It fails if you look at anything beyond galaxies. Galaxy clusters, Milgrom admits you need dark matter. Standard cosmology needs dark matter for structure formation but MOND doesn't do structure formation correctly at all, the extra gravity fucks things up. Lastly there is no MOND cosmology, previous attempts to predict the cosmic microwave background were abandoned after they became incompatible with the observations. The only thing MOND does well is galaxies which it was designed to do, it was a model to fit the data, not derived.

Lastly the radius of the universe is a number derived from cosmology, if you change the cosmology to MOND it's not the same. The point about a_0 makes no sense.

>>56845
MOND makes gravity stronger on large scales so that would increase the pull of gravity between galaxies, increasing the deceleration. MOND doesn't have a cosmology so it can't really make these predictions.


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