Talk:1758: Astrophysics

2016-11-12T10:19:10Z

Charleski:

"''Two days before the release of this comic the YouTube channel Space Time from PBS Digital Studios released a new video with the title [https://www.youtube.com/watch?v=7UNLgPIiWAg Did Dark Energy Just Disappear?]. This was based on the press coverage the paper [http://www.nature.com/articles/srep35596 Marginal evidence for cosmic acceleration from Type Ia supernovae] got, which relates to the one referenced in this comic for dark matter.''" This doesn't seem relevant. Dark energy is totally unrelated to dark matter. [[User:Schroduck|Schroduck]] ([[User talk:Schroduck|talk]]) 14:33, 11 November 2016 (UTC)
:I agree. I don't see any connection here either.[[Special:Contributions/108.162.237.37|108.162.237.37]] 16:02, 11 November 2016 (UTC)
::It is the idea that a paper seems to prove a theory wrong and then the press goes out presenting it like a proof instead of asking someone to explain to them why it doesn't fit the data. That is what this comic is about - not dark matter. See the title text. --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 18:06, 11 November 2016 (UTC)

"What is the flip the table over reference in title text. To make other do the same through mirror neruons? Still new explanation. Add more if you can" "The title text also uses Mirror neurons as a reference to a joke: it suggests to "flip this table", just as a mirror flips the image in front of it." I too want to think there is a joke here about mirror behavior or something but I just don't get it. Somebody's got to come up with a clearer, and funnier, example![[User:ExternalMonolog|ExternalMonolog]] ([[User talk:ExternalMonolog|talk]]) 16:31, 11 November 2016 (UTC)

Seems like awkward timing since https://arxiv.org/abs/1611.02269 was posted 3 days ago, a non-MOND non-dark matter theory coming from Prof. Erik Verlinde, and this particular theory starts from first principles yet matches behavior of galaxies. [[Anon]] 16:49, 11 November 2016 (UTC)
:The comic doesn't mention MOND that is only in the explanation here. It just say that all data fits with dark matter. The idea is that the department is tired of all the "proofs" that dark matter doesn't exist. Maybe Randall thinks that this new paper is just the next in line and note as explained above this paper has not been peer reviewed. So unless you're and expert and could peer review it then his theory may not fit the data and that is Randall's point. But I'm sure Randall [[955: Neutrinos|would get your]] dark matter is still on the table after this paper... --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 18:13, 11 November 2016 (UTC)

MOND is but one theory among [https://en.wikipedia.org/wiki/Category:Theories_of_gravitation many classical and quantum gravitational theories] with differing predictions for galactic rotation and lensing anomalies. There are [https://en.wikipedia.org/wiki/Dark_matter#Alternative_theories non-gravitation theories] as well. It might behoove some intrepid sole to make a table of theories and dark matter alternatives. [[User:Run, you clever boy|Run, you clever boy]] ([[User talk:Run, you clever boy|talk]])

Perhaps [[Randall]] is echoing his fellow cartoonist, {{w|Scott Adams}}, when he points out the [http://blog.dilbert.com/post/136818042136/trump-and-climate-science-master-persuader hypocrisy in science reporting]. Recently, [http://www.tau.ac.il/~kochin/ Michael S. Kochin] exposed government [http://amgreatness.com/2016/09/26/she-blinded-me-with-science/ meddling in science reportage] among other inconvenient truths. Anyone with an NSF, DoE or EPA grant knows the pressures, as [http://www.henrypayne.com/ Henry Payne], another cartoonist, [http://www.nationalreview.com/article/414359/global-warming-follow-money-henry-payne points out]. FWIW, I side with {{w|Bjorn Lomborg}}, who famously champions a [http://www.lomborg.com/ middle way] in climate science for the sake of [https://www.washingtonpost.com/news/in-theory/wp/2016/09/19/when-it-comes-to-climate-change-lets-get-our-priorities-straight/ downtrodden peoples around the world]. Additionally, [https://www.cato.org/ Cato] provides an [http://www.cgd.ucar.edu/cas/wigley/magicc/ IPCC MAGICC] [http://www.cgd.ucar.edu/cas/wigley/magicc/UserMan5.3.v2.pdf climate model] simulator for [https://www.cato.org/blog/current-wisdom-we-calculate-you-decide-handy-dandy-carbon-tax-temperature-savings-calculator anyone to examine]. Should we reconsider this explanation and the [http://www.explainxkcd.com/wiki/index.php/1732:_Earth_Temperature_Timeline#Explanation explanation] for Randall’s [https://www.xkcd.com/1732/ Earth Temperature Timeline] in this light? [[User:Run, you clever boy|Run, you clever boy]] ([[User talk:Run, you clever boy|talk]])

The current explanation doesn't cover the failure of previous experiments to detect dark matter, despite the investment of time, money and effort.  Absence of evidence may not be evidence of absence, but it's fair to say that dark matter as an explanation for observations does technically lack direct evidence/detection.  – [[Special:Contributions/141.101.98.215|141.101.98.215]] 20:44, 11 November 2016 (UTC)
:That's the rub, isn't it? Even [http://pos.sissa.it/archive/conferences/050/067/ACAT_067.pdf LHC] and [https://losc.ligo.org/tutorials/ LIGO] detections rely on theoretical templates to enhance event rates. [[User:Run, you clever boy|Run, you clever boy]] ([[User talk:Run, you clever boy|talk]])

"Of course phlogiston exists. We haven't any observational evidence for it but any idea that combustion works different doesn't fit the data."
"Of course Vulcan exists. We haven't any observational evidence for it but any idea that gravity works different doesn't fit the data."
And here we go again. [[Special:Contributions/198.41.239.32|198.41.239.32]] 23:46, 11 November 2016 (UTC)
:But this was the same way that led us to discover Neptune, Uranus, Pluto, and the Kuiper belt. [[User:Theme|Theme]] ([[User talk:Theme|talk]]) 06:49, 12 November 2016 (UTC)

Since the Bullet Cluster has been brought up again, it should be pointed out that it doesn't provide the iron-clad evidence for dark matter that some appear to think it does. Ask a MOND (or MOG)-sympathetic physicist about it and they'll direct you to [https://arxiv.org/abs/astro-ph/0702146 Brownstein & Moffat, 2007], which claims to provide a modified-gravity model that fits the data just as well (or perhaps even better) than λCDM (dark matter). I'm not going to pretend to be able to assess the model they present (or even really understand it), and I'm shamelessly parroting a recent blog-post and commentary by [https://backreaction.blogspot.co.uk/2016/10/modified-gravity-vs-particle-dark.html Sabine Hossenfelder] of the Frankfurt Institute of Advanced Study . But I think the idea that the controversy between λCDM and MOG has been settled is perhaps a distortion of the facts, and those who aren't intimately familiar with the field might be wise to avoid treating it as such. [[User:Charleski|Charleski]] ([[User talk:Charleski|talk]]) 10:19, 12 November 2016 (UTC)

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Talk:1758: Astrophysics