Talk:Bimetric gravity
This article was nominated for deletion on 15 January 2019. The result of the discussion was keep. |
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Older version of the article with content to be reused
[edit]This AfD discussion https://en.wikipedia.org/wiki/Wikipedia:Articles_for_deletion/Bimetric_gravity led to revert the article to a much lesser content. For those interested in the field, the improved content is https://en.wikipedia.org/w/index.php?title=Bimetric_gravity&oldid=879702243 Sooner or later, it will be reused here or there. --145.242.20.217 (talk) 09:27, 26 March 2019 (UTC)
- Not without a solid consensus that the "reused" content, which was removed for good reason, is actually compliant with Wikipedia's policies. And citation spamming with every paper, news story and blog post that mentions a tangentially relevant topic is not the foundation of a working editorial relationship. XOR'easter (talk) 17:56, 26 March 2019 (UTC)
- Votre action de tout supprimer sur le modèle Janus sous prétexte de "Refspam ,blog post that mentions a tangentially relevant topic" est indigne de Wikipedia et ne respecte pas le lecteur qui recherche une information objective, au lieu de faire un travail sérieux de filtration. Merci aux contributeurs qui ont réduit cet article à une simple référence unique! Alors que dans les autres pays l'information reste accessible et disponible pour le lecteur en veillant à un équilibre des deux opinions qui s'opposent (un des principes fondateurs de WP) surtout en France. Signé un contributeur français. --Adiabatique (talk) 20:35, 24 February 2020 (UTC)
- Automatic translation of the message above (I'm not Adiabatique).
- "Your action to delete everything on the Janus model under the pretext of "Refspam, blog post that mentions a tangentially relevant topic" is unworthy of Wikipedia and does not respect the reader who seeks objective information, instead of doing a serious job of filtration. Thank you to the contributors who reduced this article to a single unique reference! While in other countries the information remains accessible and available to the reader while ensuring a balance of the two opposing opinions (one of the founding principles of WP) especially in France. Signed by a French contributor. --Adiabatic (talk) 20:35, 24 February 2020 (UTC)". --82.126.55.46 (talk) 00:36, 9 July 2020 (UTC)
Special for XOR'easter
[edit]The following discussion is closed. Please do not modify it. Subsequent comments should be made on the appropriate discussion page. No further edits should be made to this discussion.
Describe below which "refs include unreliable, unreviewed, pop-science hype and WP:FRINGE material", and bring evidence with each of your asserts (your own sentiment about what your are naively considering unreliable, unreviewed, pop-science hype and WP:FRINGE material is not at all an evidence, of course). Try to convince us. Have a nice day. --91.169.1.118 (talk) 19:30, 26 March 2019 (UTC)
- Let's see. D'Agostini and Petit (2018) is a recent, unevaluated primary source, and the only citations to it have been by the authors themselves. For our purposes, that's worthless. Next is a bibliography hosted on Academia.edu, which counts for nothing, and it degenerates into a ramble at the end which makes enough claims about enough people that relying on it would violate WP:BLP as well as WP:RS. The sentence
Among them, the Janus cosmological model is the most advanced model
is completely unsupported by reliable sources and cannot be said in Wikipedia's voice. The archived web page by Riazuelo may be acceptable under WP:SPS, but it calls Petit's work garbage, and you might not want to include that one after all. Riazuelo concludes that "JPP" makesPlusieurs erreurs de base ... qui disqualifient irrémédiablement le modèle
. Farnes (2018) mentions Petit and d'Agostini only to dismiss their theory in a single sentence as "incompatible with observations". If this citation is supposed to support the claim that the Janus cosmological model has beendeeply ... discussed among cosmologists
, well, it doesn't. Next we have Damour (2019), who says thatle "modèle Janus" est physiquement (et mathématiquement) incohérent
. None of these amount to support for the idea that the Janus modelis the most advanced model
, to say the least. Next we have another primary source, not even formally published, by a collaborator of Petit. Then we have a primary source, published yet too new to have been evaluated by the wider community, which I removed already. - Yeah, not looking good so far. To put it bluntly, I don't have to convince you. On the contrary, you have the responsibility to convince the rest of the community. XOR'easter (talk) 20:06, 26 March 2019 (UTC)
- Note what WP:BRD says:
If your edit gets reverted, do not revert again.
You edited, with a misleading edit summary; I reverted; you went on to revert again. You're in the wrong here. XOR'easter (talk) 20:10, 26 March 2019 (UTC)- Let's see closer. Let's start by copying the content you vandalized because of your own personal war against Petit's works, to put it bluntly (May I guess they are so much better than yours? - Yes I know, you will try to deny it):
[1] Among them, the Janus cosmological model is the most advanced model.[2] It has then been evaluated by peers up to the point to be deeply and publicly discussed among cosmologists.[3][4][5][6][7][8]
These models, and others ones, have been introduced to develop an answer to the crisis in the current standard cosmological model.[9][10][11][12][13][14][15][16][17][18][19][20][21][22] [23][24][25][26][27][28]
References
- ^ D’Agostini, G.; Petit, J. P. (2018-06-06). "Constraints on Janus Cosmological model from recent observations of supernovae type Ia". Astrophysics and Space Science. 363 (7): 139. doi:10.1007/s10509-018-3365-3. ISSN 1572-946X.
- ^ Paul, Bruno (2019-03-21). "Bibliographie du modèle cosmologique "Janus" ~ Bibliography of the "Janus" cosmological model". Academia.edu.
- ^ O'Dowd, Matt (7 February 2019). "Sound Waves from the Beginning of Time". PBS Space Time. PBS. 16 minutes in. Retrieved 8 February 2019.
An alternate model that how negative mass might behave: in so-called 'bimetric gravity' you can have positive and negative masses, but each is described by its own set of Einstein field equations. That's kinda like having 'parallel spacetimes', one with positive and one with negative masses, which can still interact gravitationally. In these models, like masses attract and opposite masses repel… and you don't get the crazy 'runaway motion' that occurs if you put both positive and negative masses in the same spacetime. So no perpetual motion machines… It can also be used to explain dark energy and dark matter. An example is the Janus model of Jean-Pierre Petit. This is a much more sophisticated model than the one by Jamie Farnes. It is however just as speculative.
- ^ Riazuelo, Alain (2006-12-04). "Analyse d'un article de cosmologie de Jean-Pierre Petit". iap.fr. Retrieved 2019-03-26.
{{cite web}}
: Check|archive-url=
value (help); Cite has empty unknown parameter:|dead-url=
(help) - ^ Farnes, J. S. (2018-12-01). "A unifying theory of dark energy and dark matter: Negative masses and matter creation within a modified ΛCDM framework". Astronomy & Astrophysics. 620: A92. doi:10.1051/0004-6361/201832898. ISSN 0004-6361.
- ^ Thibault Damour, IHES, 01/04/2019, http://www.ihes.fr/~damour/publications/JanusJanvier2019-1.pdf
- ^ Frédéric Henry-Couannier, Consistency of JP. P and S.H Janus anti-gravity theories. darksideofgravity.com (17 June 2017). https://www.darksideofgravity.com/Consistency.pdf
- ^ J.P.Petit, G.D’Agostini, and N.Debergh, « Physical and mathematical consistency of the Janus Cosmological Model (JCM) », Progress in Physics, vol. 15, issue 1, http://www.ptep-online.com/2019/PP-56-09.PDF
- ^ Clifton, Timothy; Ferreira, Pedro G.; Padilla, Antonio; Skordis, Constantinos (March 2012). "Modified Gravity and Cosmology". Physics Reports. 513 (1–3): 1–189. doi:10.1016/j.physrep.2012.01.001.
- ^ "Du Big Bang à la mission Planck: Questions restées sans réponse". Techno-Science.net (in French). Retrieved 2019-03-26.
- ^ "Un Univers sans matière noire?". CNRS Le journal (in French). Retrieved 2019-03-26.
- ^ "JANUS-FACED COSMOLOGY". www3.amherst.edu. Retrieved 2019-03-26.
- ^ "Physique : faut-il abandonner l'hypothèse de la matière noire pour expliquer l'Univers ?". Sciences et Avenir (in French). Retrieved 2019-03-26.
- ^ "Is the search for dark energy a dead end?". Cosmos Magazine. Retrieved 2019-03-26.
- ^ "What is Dark Matter? Even the Best Theories Are Crumbling". The Crux. 2018-09-21. Retrieved 2019-03-26.
- ^ Monday, Tyler Krueger | Published:; May 07; 2018. "The case against dark matter". Astronomy.com. Retrieved 2019-03-26.
{{cite web}}
:|last3=
has numeric name (help)CS1 maint: extra punctuation (link) CS1 maint: numeric names: authors list (link) - ^ Bosma, A. (1998). "The Dark Matter problem". Celestial Mechanics and Dynamical Astronomy. 72 (1/2): 69–90. doi:10.1023/A:1008366614769.
- ^ Smirnov, Juri. "Dark matter may not actually exist – and our alternative theory can be put to the test". The Conversation. Retrieved 2019-03-26.
- ^ Siegel, Ethan. "There's A Debate Raging Over Whether Dark Matter Is Real, But One Side Is Cheating". Forbes. Retrieved 2019-03-26.
- ^ Moskvitch, Katia (2018-09-28). "What if everything we know about dark matter is totally wrong?". Wired UK. ISSN 1357-0978. Retrieved 2019-03-26.
- ^ Lopez-Corredoira, Martin (2018-08-28). "Problems with the dark matter and dark energy hypotheses, and alternative ideas".
{{cite journal}}
: Cite journal requires|journal=
(help) - ^ https://www.livescience.com/64724-hubble-constant-measured-precisely-with-quasars.html
- ^ http://adsabs.harvard.edu/abs/2018arXiv180200081M
- ^ http://adsabs.harvard.edu/abs/2014MNRAS.442.2362P
- ^ http://adsabs.harvard.edu/abs/2012arXiv1204.2546K
- ^ https://darkmattercrisis.wordpress.com/2012/04/17/german-tv-tip/
- ^ https://aeon.co/ideas/has-dogma-derailed-the-scientific-search-for-dark-matter
- ^ http://adsabs.harvard.edu/cgi-bin/bib_query?arXiv:1802.02579
- XOR'easter is right here, and the proposed 'expansion' is a not an improvement. Headbomb {t · c · p · b} 20:58, 26 March 2019 (UTC)
- I don't have a
personal war against Petit's works
. I haven'tvandalized
anything. And as far as the references you have provided, they don't make the case you want them to. They talk about the nature of dark matter still being unknown. Some of them are primary, like this fellow doing a pop-science presentation of his own research. Fine for him; irrelevant for our purposes here. The lengthy conference proceedings item doesn't seem to mention bimetric gravity at all. (The piece in Wired even makes the case that gravitational waves from neutron-star collisions have ruled out a number of modified-gravity theories, which is good for dark matter. And Ethan Siegel's column for Forbes comes down unambiguously in favor of dark matter. Open questions, yes; "crisis", no.) Basically, it looks like a heap of superfluous footnotes intended to create the impression that there is more support for the claim they're attached to than there really is. They don't all suggest there is a "crisis" with Lambda-CDM, and using them here is WP:SYNTH. XOR'easter (talk) 21:06, 26 March 2019 (UTC) - Oh, the JANUS-FACED COSMOLOGY link isn't about the "Janus cosmological model". It's a guy who thinks protons are black holes, complaining that cosmologists are dishonest and two-faced. XOR'easter (talk) 21:37, 26 March 2019 (UTC)
- I note that our IP-hopping colleague has fallen back into old habits and edited a post that has already been commented upon, thereby violating Talk-page etiquette and just generally making life more confusing for the rest of us. The extra source they added just makes the WP:SYNTH case worse. It does not claim that there is a "crisis" with the Lambda-CDM model. The headline says that
Something Is Not Quite Right
, and the text makes the modest suggestion thatnew physics may be needed
, quoting an outside expert as saying, "I think that our confidence is growing that there's something really interesting going on." Calling this a "crisis" is spin. Nor does the story make any connection between the research it describes and bimetric gravity. So: citation spamming, misrepresentation of sources, and synthesis. XOR'easter (talk) 22:17, 26 March 2019 (UTC)- Thanks to CEC0:1052:2832:4259:8326:B8E:44AE for your contribution :) I guess many contributors will continue to add sources to this list in the weeks/months/years to come. Oh, and thank you very much XOR'Easter to bring this page to the attention of everybody! It demonstrates perfectly what I strongly suspected: your censorship attitude. The test you failed is perfectly relevant. Very interesting reading for sure! The conclusion allows me to save my time and focus right now on contributing to WP elsewhere. You will learn about it one day perharps (too late of course).
- I note that our IP-hopping colleague has fallen back into old habits and edited a post that has already been commented upon, thereby violating Talk-page etiquette and just generally making life more confusing for the rest of us. The extra source they added just makes the WP:SYNTH case worse. It does not claim that there is a "crisis" with the Lambda-CDM model. The headline says that
- I don't have a
- XOR'easter is right here, and the proposed 'expansion' is a not an improvement. Headbomb {t · c · p · b} 20:58, 26 March 2019 (UTC)
Whatever you try to explain about your motives, you still rely on a feeling "about any conjecture that had survived the slightest bit of critical scrutiny", without precisely defining what is the "slightest bit of critical scrutiny" (cf questions in my test you don't even start to answer). You failed the test, and you just deny it. I can understand that, and believe me I just don't need to convince you. Ultimately, you can't stop the truth out. Nobody can. --145.242.20.217 (talk) 09:31, 23 January 2019 (UTC)
- Your arguments are so poor. I already know you know nothing about maths because you didn't understand papers like [1] and [8], which have destroyed once and for all the illusions of the Lambda-CDM model and of the reputation of Damour/Deruelle/Blanchet. Sure you know them because you're french-speaking.
- [1] and [8] : peer-reviewed primary sources are valid primary sources to be used in WP, whatever you sentiment. Peer-review means evaluation, if you know what peer-reviewed is. You're misleading. You wrote : "For my purposes, that's worthless", but who cares about your sentiment?
- The bibliography [2] hosted on Academia.edu is a pretty comprehensive one, with links for each paper. Very useful, and this kind of basic information does not need to be peer-reviewed (ok you ignore what is a peer-review but...). It can be considered as a secondary source. The "ramble" at the end is not cited in WP page, and the ref is only used for the bibliography. Here too you're misleading.
- The sentence "Among them, the Janus cosmological model is the most advanced model" is a basic fact, completely supported by ref [2]. You can rewrite it "Among them, the Janus cosmological model has the richest bibliography" if you prefer.
- Yes, I want the archived web page by Riazuelo to be referenced. Whatever you might think, I'm interested in true facts. Don't you? Surely not.
- Riazuelo and Farnes are some of the cosmologists who have been interested in Janus, up to the point to publish their views about it. It demonstrates that Janus is NOT ignored by the community. The papers by Henry-Jouannet and Damour/Deruelle/Blanchet are perfect known examples that the Janus cosmological model has been "deeply ... discussed among cosmologists". Here too, you're misleading. And by the way, guess what : the refs I used are linked to their own single sentence. You don't even know that, or you're misleading. Whatever the content of these papers, they demonstrate what I wrote and I want them to be referenced (true facts, you remember?). Read again : I never wrote they were fans of JCM. The fact that Henry-Couannier wrote a paper 15 years before with Petit is certainly not a problem, and is misleading. It is a valid primary source as a paper on cosmology published on his own professional web site. And secondary sources are NOT mandatory on WP (except when you're the only one to censor facts of course).
- The others refs are not simple "talk about the nature of dark matter still being unknown" : you're misleading. They say explicitly that this way of research is in crisis/a dead end. The fact that some of them doesn't seem to mention bimetric gravity at all is NOT relevant here : these refs support the sentence : "These [bimetric] models, **and others ones**, have been introduced to develop an answer to the crisis in the current standard cosmological model."
- If "the case that gravitational waves from neutron-star collisions have ruled out a number of modified-gravity theories, which is good for dark matter", it is good for Bimetric theories too. You're misleading. And read the title of the Wired article.
- "there's a debate raging about dark matter" obviously means 100% cosmologists except Petit are fully convinced about Lambda-CDM model. Of course. Repeat after me : C-R-I-S-I-S.
- REFSPAM attack : when your opponent has no ref, delete the sentence. When he has a few refs it's only a few, it's not convincing and delete them. When he has a lot and a lot, it's REFSPAM. Ridiculous. And when I list them only, you call that WP:SYNTH. Even more ridiculous.
- "Oh, the JANUS-FACED COSMOLOGY link isn't about the Janus cosmological model": yes, and you deleted it before, 3 times, without even reading it. Nice job. And about your sentiment relative to its content, nobody cares here. Irrelevant.
- Of course ref 22 is a perfect secondary source, highly visible. Quotations :
Something isn't quite right in the universe. At least based on everything physicists know so far. ... the universe is exploding outward faster than it was in the beginning. That shouldn't be the case, based on scientists' best descriptor of the universe. ...the current model is missing crucial new physics, Lambda-CDM...can't explain why the universe is expanding faster now than it did early on. That means that either the LCDM model is WRONG or the measurements of expansion rate are. ..."So when a group comes along like this and uses a completely different set of tools… and gets the same answer, then you can pretty quickly conclude that that answer is not a result of some serious effect in the techniques," said Adam Riess, a Nobel laureate ...As for explaining what possibly exotic physics might explain their mismatch in expansion-rate measurements, that's way down the line.
- Well OBVIOUSLY, there is not a crisis with Lambda-CDM. The only crisis lays in the head of XOR'Easter.--91.169.1.118 (talk) 21:52, 27 March 2019 (UTC)
Thank you for that wall of text. I note that you asserted, You wrote : "For my purposes, that's worthless", but who cares about your sentiment?
That is not what I wrote. I said For our purposes, that's worthless
(emphasis added), referring to the necessity of evaluating all sources in light of Wikipedia's policies. You misrepresent me, by outright misquotation. You misrepresent the sources you heap upon us. You try to pull them together to reach a conclusion that none of them do. Finally, you resort to personal attacks. Plainly, you are not here to build an encyclopedia. XOR'easter (talk) 22:02, 27 March 2019 (UTC)
- I think 91.169.1.118 has correctly asserted that when you use "our purposes" it only means your own opinion. Nothing could be used to say you represent something more than you when you wrote your "worthless" sentiment. For instance I consider the ref [2] as valid and useful. Then writing "For my purposes, that's worthless" is not misrepresenting you at all. And saying that following this hypothetical misrepresentation implies 91.169.1.118 misrepresented any of the other sources is a vastly misleading argument, once again. With this new case, you demonstrated **you** are not here to build an encyclopedia, but only to censor useful contributions **you** do not agree with the described ideas (your personal war against some ideas, as already said), in a blatant violation of NPOV. --194.206.71.161 (talk) 12:31, 28 March 2019 (UTC) — 194.206.71.161 (talk) has made few or no other edits outside this topic.
- How's the weather in Fresnes? Is it comfortable for socks?
- I stand by my assessment of every source that I evaluated. For example, reference 2 is a self-published source, and merely listing a litany of papers by the creators of a model does nothing to establish that the model in question is "the most advanced". Nor did I say that this misrepresentation
implies 91.169.1.118 misrepresented any of the other sources
; I evaluated those sources on their own merits, and found them to include clickbait, a crackpot website, self-promotion, a humdrum paper from two decades ago called "the dark matter problem" that doesn't actually argue there's a problem with dark matter, and a few that say there's an interesting puzzle but not a "crisis". I'm not the one with a "personal war" here. At the most, I'm vaguely exasperated that I have to spend the limited time I have for Wikipedia editing each day on this instead of anything actually fun. XOR'easter (talk) 14:00, 28 March 2019 (UTC)- Added more primary and secondary refs : [23] to [28] --91.169.1.118 (talk) 18:49, 28 March 2019 (UTC)
- Yet another secondary source for the Dummies : "Best-Yet Measurements Deepen Cosmological Crisis" [1]
- Added more primary and secondary refs : [23] to [28] --91.169.1.118 (talk) 18:49, 28 March 2019 (UTC)
[Nobel price winner] Riess also thinks that the discrepancy is pointing fingers at cosmologists’ standard model. “At some point, you have to start saying the universe has another wrinkle in it, in the cosmological model—in the composition of the universe or in some feature of dark matter or dark energy—[that] could also potentially explain this,” he says. “You have to give that some serious consideration.”
Is there a crisis in cosmology ?
[edit]After Smolin and Woit, is this yet another "worthless" reference according to you XOR'easter? Hossenfelder : "Lost in Maths"[2]
"In her new book, Lost In Math, Sabine Hossenfelder adroitly confronts this crisis head on.... The book is a wild, deep, thought-provoking read that would make any reasonable person in the field who's still capable of introspection doubt themselves." ―Forbes "Lost in Math is self-aware and dosed with acerbic wit, and it asks bold questions." ―Nature "Hossenfelder's jaunt through the world of theoretical physics explicitly raises the question of whether the activities of thousands of physicists should actually count as 'science.' And if not, then what in tarnation are they doing?" ―Weekly Standard
XOR'easter, do you think we should create a new page on WP using all these refs (more to come) and write that according to them there is NOT a crisis in cosmology? This could be very useful because so much well-known people and secondary sources are "misunderstanding" the situation... --91.169.1.118 (talk) 20:01, 28 March 2019 (UTC)
- Congratulations! You've discovered that people sell books using sensationalist flap copy! Also, the brunt of Hossenfelder's critique is about the elevation of criteria like "naturalness" beyond their deserved status (a complaint with which I have some sympathy), which is barely relevant to the topic of this page at all. And the arguments of Smolin and Woit are even further afield. You can continue to Google "crisis" and "cosmology" all you like, I suppose, but I don't think you're doing yourself any favors. XOR'easter (talk) 20:15, 28 March 2019 (UTC)
- XOR'easter, why a crisis in cosmology can only exist when you, alone, decide there is indeed a crisis in cosmology ? Why have you failed to pass the test you bring to our attention and why are you constantly failing ? Why are you censoring and vandalizing sourced valid contributions in WP? Why every single person who is not sharing your so limited view is obviously wrong according to you alone?
You say the proposed sources are not enough. Please answer these questions : 1) where is written that the present article should be considered with different rules than others WP articles ? 2) to clarify Notability, give us a precise list of the minimum mandatory criteria (qualitatively and quantitatively) to add the proposed sentences in the article, according to yourself (for instance: the authors must received Nobel Price, one of them has to be named Time's magazine Man of the Year). 3) map each criteria with a WP rule (not a guideline) If you fail to provide 3) in a few days, then this would mean your approach is arbitrary. Such approach, a.k.a censorship, has no place in WP. --80.215.195.0 (talk) 09:05, 20 January 2019 (UTC)
References
I see no reason to reply to questions clearly asked in bad faith whose premises themselves deny reality (for example, I am not considering this article with different rules than others [sic] WP articles
). XOR'easter (talk) 21:05, 28 March 2019 (UTC)
- Free advice, honestly given and well meant: Read the critical reviews of Hossenfelder's book, go back and read the responses to Smolin and Woit from the heyday of the String Wars, read the journal articles that cite the ones you put in your list and which suggest mundane explanations for the various dark-matter-related anomalies. You needn't agree with them all, but it might help you appreciate the diversity of issues in play, how many different puzzles one encounters at the knowledge frontier, and why we cannot simply declare in Wikipedia's voice that there is "a crisis". At the very least, the exercise may give you a better understanding of your adversaries. XOR'easter (talk) 23:34, 28 March 2019 (UTC)
- We have all understood that you're a fake contributor to WP, and a real censor. Whatever can be said, you have already decided to censor anything you want, and you play the game to divert attention on whatever rule your opponent has violated, agreeing to you only. With people like you, only one thing can be done : ignore you, until some other admins will ban you when they will be tired of your censorship and the bad reputation of your "work" here. Why don't you write yourself this SYNTH you kindly recommend, and source each sentence like your opponent has always done? Why won't you consider this a original work, which then cannot be published on wp? You're full of contradictions in your poor way to argue, and I don't even speak about the way you relate things in the admin pages to try to ban "bad IPs" using an expected consensus you would have deeply influenced when your opponent cannot. You even recognized the 3RR procedure was begun by YOU, and not by your opponent. Like with any censor, the fault according to you is always on the writer, never on you. And you smile : "oh you don't want to debate with me, that's personnal attack". Who do you think you are deceiving, except yourself?
- --194.206.71.161 (talk) 13:20, 29 March 2019 (UTC)
- I offered you honest advice, well after someone else told you to stop beating a dead horse, and yet I'm the one you're upset with. Interesting. XOR'easter (talk) 14:22, 29 March 2019 (UTC)
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