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::::::::::At ''[[frequency|f]]'' = 1 [[Hertz|Hz]], a quantum's energy (''[[Energy|E]] = [[frequency|f]][[Planck constant|h]]'') is equal to ''[[Planck constant|h]]'' (the breakeven point between [[Wave–particle duality|wave-likeness]] and [[Wave–particle duality|particle-likeness]]), while the quantum's [[Compton wavelength]] (the radius of [[nonlocality]], instantaneous propagation) is 1 [[light-second]] (300 thousand kilometres). According to the theory of relativity, superluminal propagation is propagation into the past. Therefore:
::::::::::At ''[[frequency|f]]'' = 1 [[Hertz|Hz]], a quantum's energy (''[[Energy|E]] = [[frequency|f]][[Planck constant|h]]'') is equal to ''[[Planck constant|h]]'' (the breakeven point between [[Wave–particle duality|wave-likeness]] and [[Wave–particle duality|particle-likeness]]), while the quantum's [[Compton wavelength]] (the radius of [[nonlocality]], instantaneous propagation) is 1 [[light-second]] (300 thousand kilometres). According to the theory of relativity, superluminal propagation is propagation into the past. Therefore:
::::::::::*A relativistic wave, whose frequency is above 1 [[Hertz|Hz]], begins its second [[Period (physics)#Frequency of waves|period]] in the future; the third [[Period (physics)#Frequency of waves|period]], still further in the future, and so on. Such a wave is an [[electromagnetic wave]]; in its quantum—the [[photon]]—the [[Wave–particle duality|particle-like]] magnetic phase dominates over the [[Wave–particle duality|wave-like]] electric phase.
::::::::::*A relativistic wave, whose frequency is above 1 [[Hertz|Hz]], begins its second [[Period (physics)#Frequency of waves|period]] in the future; the third [[Period (physics)#Frequency of waves|period]], still further in the future, and so on. Such a wave is an [[electromagnetic wave]]; in its quantum—the [[photon]]—the [[Wave–particle duality|particle-like]] magnetic phase dominates over the [[Wave–particle duality|wave-like]] electric phase.
::::::::::*A relativistic wave, whose frequency is below 1 [[Hertz|Hz]], begins its second [[Period (physics)#Frequency of waves|period]] in the past; the third [[Period (physics)#Frequency of waves|period]], still further in the past, and so on.<ref>Corning, Peter A. ♦ [http://books.google.com/books?id=V9Dkpby09t8C&pg=PA340&lpg=PA340&dq=%22gravitation+carries+no+entropy%22&source=bl&ots=aVLXkBqoFq&sig=bdup46_MU9lDF3k0tEjt5o7hLKk&hl=en&ei=Vdo2Ta7UCYSUOr-iiOwD&sa=X&oi=book_result&ct=result&resnum=1&ved=0CBIQ6AEwAA#v=onepage Holistic Darwinism: synergy, cybernetics, and the bioeconomics of evolution] University of Chicago Press, 2005, p. 340 ''(Since the gravitational field propagates into the past, its entropy decreases with time.)''</ref> Such a wave is a [[Gravitomagnetism|gravitoelectromagnetic wave]]; in its quantum—the [[graviton]]—the [[Wave–particle duality|wave-like]] electric phase dominates over the [[Wave–particle duality|particle-like]] magnetic phase.
::::::::::*A relativistic wave, whose frequency is below 1 [[Hertz|Hz]], begins its second [[Period (physics)#Frequency of waves|period]] in the past; the third [[Period (physics)#Frequency of waves|period]], still further in the past, and so on.<ref>Corning, Peter A. ♦ [http://books.google.com/books?id=V9Dkpby09t8C&pg=PA340&lpg=PA340&dq=%22gravitation+carries+no+entropy%22&source=bl&ots=aVLXkBqoFq&sig=bdup46_MU9lDF3k0tEjt5o7hLKk&hl=en&ei=Vdo2Ta7UCYSUOr-iiOwD&sa=X&oi=book_result&ct=result&resnum=1&ved=0CBIQ6AEwAA#v=onepage Holistic Darwinism: synergy, cybernetics, and the bioeconomics of evolution] University of Chicago Press, 2005, p. 340 ''(Since the gravitational field propagates into the past, its entropy decreases with time.)''</ref> Such a wave is a [[Gravitomagnetism|gravitoelectromagnetic wave]]; in its quantum—the [[graviton]]—the [[Wave–particle duality|wave-like]] electric phase dominates over the [[Wave–particle duality|particle-like]] magnetic phase.<ref>{{cite web| url=http://www.answers.com/topic/gravitoelectric-field |title=McGraw-Hill Dictionary of Scientific and Technical Terms |accessdate=2 Dec 2010}}</ref>
::::::::::Conclusion:
::::::::::Conclusion:
::::::::::#[[Gravitomagnetism|Gravitoelectromagnetic wave]]s, whose frequencies are below 1 [[Hertz|Hz]], are undetectable.<ref>[[Paul_Davies|Davies, P. C. W.]] ♦ [http://www.google.com/search?tbs=bks%3A1&tbo=1&q=%22The+weakness+of+gravity+means+that+experiments+with+gravitons%2C+unlike+those+involving+photons%2C+are+out+of+the+question%22&btnG=Search+Books The search for gravity waves] CUP Archive, 1980, p. 129</ref><ref>When the average [[Compton wavelength]] of the gravitons is 300 thousand kilometres, it does not matter whether one detects the velocity of a single graviton or the [[group velocity]] of a myriad of gravitons—in both cases, the signal will arrive to both arms of the interferometer simultaneously.</ref>
::::::::::#[[Gravitomagnetism|Gravitoelectromagnetic wave]]s, whose frequencies are below 1 [[Hertz|Hz]], are undetectable.<ref>[[Paul_Davies|Davies, P. C. W.]] ♦ [http://www.google.com/search?tbs=bks%3A1&tbo=1&q=%22The+weakness+of+gravity+means+that+experiments+with+gravitons%2C+unlike+those+involving+photons%2C+are+out+of+the+question%22&btnG=Search+Books The search for gravity waves] CUP Archive, 1980, p. 129</ref><ref>When the average [[Compton wavelength]] of the gravitons is 300 thousand kilometres, it does not matter whether one detects the velocity of a single graviton or the [[group velocity]] of a myriad of gravitons—in both cases, the signal will arrive to both arms of the interferometer simultaneously.</ref>

Revision as of 16:02, 19 January 2011

WikiProject Physics
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Physics portal for 2011

I just wanted to let everybody know that I set up the page for Selected articles and Selected pictures for the Physics Portal in 2011 (January to December), in case anyone wants to take a look for any discrepancies. ---- Steve Quinn (talk) 05:31, 27 December 2010 (UTC)[reply]

Hi, I just wanted to alert you all that the Laplace–Runge–Lenz vector will be appearing on the Main Page tomorrow, that is, on December 30th. I was hoping to make a lead animation for the occasion, similar to the ones I made for Newton's theorem of revolving orbits, but alas, I won't manage to finish it in time. Tomorrow I'll be doing my best to watch over the article; but since I'll also be busy in real life, I'd appreciate any extra help from my friends and colleagues here. Thank you very much! :) Willow (talk) 18:34, 29 December 2010 (UTC)[reply]

I was thinking that this article could use an image in the introduction. I was going to place it there, until I noticed it is on the Main Page at this time. So being a sane person at times, I have not done so. However, if no one has a problem with this image in the introduction, I will place it there in about two hours. ---- Steve Quinn (talk) 01:16, 30 December 2010 (UTC)[reply]
That image cannot be used under a free license, so it will not show up on the main page BTW. I also do not see how one would justify the rationale for the LRL vector article, it's just a copyrighted image of the solar system, and not a very good one at that. There's no link between the image and the vector, so its inclusion would be more puzzling than anything else regardless of the copyright status. Headbomb {talk / contribs / physics / books} 01:23, 30 December 2010 (UTC)[reply]

Hi, thank you both for giving this serious consideration. I agree that it would be too difficult to add an image into the lead now. My plan had been to add a glowing LRL vector to the planet in one of my earlier animations (e.g., this one), but I simply ran out of time. Oh well, maybe in the next universe... ;) Willow (talk) 01:39, 30 December 2010 (UTC)[reply]

OK thanks for the feedback. As time passed, after my last response, I began to think this image was not a good idea also. And I agree this is an inferior image of the solar system. So, I won't be attempting to add the image to this article. I guess it was a hasty decision, on my part. ---- Steve Quinn (talk) 03:08, 30 December 2010 (UTC)[reply]

February theme of the month

Selected articles, February 2011

There are scientific journals that focus on physics research. For example, Annalen der Physik is the oldest physics journal. It appears to cover all topics in the physics discipline by reporting original work in the areas of experimental, theoretical, applied and mathematical physics. Advances in Physics focuses on interdisciplinary, critical reviews with topics ranging over condensed matter physics, statistical mechanics, quantum information, cold atoms, soft matter physics, and biophysics. Space Science Reviews only synthesizes current results in space science research, which can impact the various related fields and related insturmentation.

Below is a list of general interest articles pertaining to physics related scientific journals:

The theme of the month (February) for the selected article at the Physics portal is "physics related scientific journals". I am looking for recommendations for such journals here. Maybe from experience, the physics community is aware of the most read or consulted journals in their field, or at their work place. I think related engineering journals are also acceptable for this theme. What is recommended for positioning some of the most the cited journals? ---- Steve Quinn (talk) 18:26, 2 January 2011 (UTC)[reply]

Furthermore, I could even add a couple of sentences stating that these are journals suggested by the Wikipedia physics community or WikiProject Physics members (or something like that). ---- Steve Quinn (talk) 18:32, 2 January 2011 (UTC)[reply]
This could help: Wikipedia:WikiProject Physics/Taskforces/BPH/Publications/Popular_pages. Headbomb {talk / contribs / physics / books} 22:00, 2 January 2011 (UTC)[reply]
Headbomb, yes, this will help a lot. Thanks. In fact I will do this theme based on this page. Also, I was thinking if I state that a set of publications is "suggested" by WikiProject Physics members that may not work. I mean, the community can make suggestions. However, making an explicit statement may contradict neutrality, or a neutral point of view. ---- Steve Quinn (talk) 17:42, 3 January 2011 (UTC)[reply]
I took a shot at selecting the most widely known journals of physics, as well as all the national journals I could think of, plus a few journal of high historical value. I might have missed a few. Headbomb {talk / contribs / physics / books} 02:27, 4 January 2011 (UTC)[reply]
Headbomb, this is worth starting a new section on this page entitled "WOW!". But the members here would probably eshew such titles as pure POV :>)
Really, excellent work. This is what I was looking for. Your knowledge and experience has helped a lot with this topic. I appreciate it very much. I'll work on fleshing it out into some sort of prose version. Of course, input for developing the prose is welcome - if you have time. I know we editors are all busy here at Wikipedia. So, also, thanks for taking the time to do this. ---- Steve Quinn (talk) 06:51, 4 January 2011 (UTC)[reply]

Atmospheric reentry

Atmospheric reentry naming is under discussion, see talk:Atmospheric reentry, where the definition, usage, and relation to natural phenomena, and balance is noted. As this is a physics of air-solid interaction topic, I thought I'd let you know. 184.144.161.173 (talk) 20:17, 2 January 2011 (UTC)[reply]

I removed a mention of a supersymmetry representation called "Adinkras" from the article on the West African Adinkra symbols, but the removal was reverted. From my searching these physics "adinkras" have gained little outside attention, but people here might know better. I don't think this physics concept belongs at all in an article on a protoscript - can anyone suggest a better article for that content, to which a hatnote or other short note could point? Fences&Windows 21:44, 3 January 2011 (UTC)[reply]

Can perhaps be moved to one of the articles on supersymmetry. Count Iblis (talk) 01:00, 4 January 2011 (UTC)[reply]

United States gravity control propulsion research

I don't really have much of a horse in this race, but there seems to be an edit war over in United States gravity control propulsion research, entering and removing the page from the General Relativity category. The page is supported by the Relativity Task Force. It seems to me that you guys should be making the call here. Thanks! xod (talk) 18:33, 7 January 2011 (UTC)[reply]

The Fringe noticeboard made notice that this category had been removed some times in the past. Several editors removing it over a time period of months, and one editor restoring it repeatedly is not an edit war, but a showing of consensus by multiple editors that it does not belong. SchmuckyTheCat (talk)
Apparently Tcisco (talk · contribs) (not a member of the taskforce) put this article into Category:General relativity inappropriately which started all this. AnomieBOT then added it to the Physics project and Relativity taskforce on that mistaken basis. I removed it. JRSpriggs (talk) 10:30, 8 January 2011 (UTC)[reply]

Kerr metric

An IP editor has made a substantial addition to Kerr metric (edit | talk | history | protect | delete | links | watch | logs | views), amounting to a claim of independent discovery by someone else. This could definitely stand vetting. --Christopher Thomas (talk) 04:02, 10 January 2011 (UTC)[reply]

The abstract of the second of his three references, "On the Nutku-Halil solution for colliding impulsive gravitational waves" by Chandrasekhar and Ferrari, says that the Nutku-Halil solution is similar to the Kerr solution in a very abstract way, not that they are the same. So perhaps we should create an article on the Nutku-Halil solution. But this new section in the Kerr article should be removed or rewritten. JRSpriggs (talk) 04:41, 10 January 2011 (UTC)[reply]
Tracking link: Nutku-Halil solution -- Chronulator (talk) 17:06, 16 January 2011 (UTC)[reply]

Broken rewrite of Neodymium magnet

I cam across Neodymium magnet today, and noticed that it wasn't tagged for the Physics project. It needs an assessment. Additionally, there's a problem concerning an excessivey bold rewrite in 2009 which seems to have negatively affected the article: see talk:Neodymium magnet#Broken rewrite for details. Chris Cunningham (user:thumperward: not at work) - talk 08:45, 14 January 2011 (UTC)[reply]

β-disintegration

I've added β-disintegration, and several other spellings of the same, as redirects to beta decay, based on my ancient undergraduate physics memories. (See my recent edits for all of these) Can anyone more current than me confirm that these are indeed synonyms? -- Gigacephalus (talk) 14:27, 16 January 2011 (UTC)[reply]

Per WP:NOTPAPER, as long as these are plausible and you can state with reasonable confidence that you saw them in literature or teaching material somewhere, I don't see any problem. --Christopher Thomas (talk) 05:39, 19 January 2011 (UTC)[reply]

I have a question about the notability of a biography of a physicist (Samo Stanič) and some project members here may have valuable input. Please respond at Wikipedia talk:WikiProject Biography/Science and academia#Samo Stanič. Thanks. --Crusio (talk) 16:38, 18 January 2011 (UTC)[reply]

Speed of gravity

Could someone have a close look at what has been happening recently at article Speed of gravity (edit | talk | history | protect | delete | links | watch | logs | views), specially in this addition to the lead by user Antichristos (talk · contribs)? I have added a cn-tag and removed the bolding ([1]), but I think this could need an eye or two. DVdm (talk) 08:09, 19 January 2011 (UTC)[reply]

I don't know if that was a reaction to this, but I notice that Xhanthippe already removed the paragraph, which was then immediately restored with 3 refs. Anyway, I'm also wondering about whether the next paragraph ("In relativistic quantum theory...") is at its place in the lead. It looks a bit overwhelming to me. I had removed it previously and had a question about it on the talk page. Some work was done on it by Antichristos, but I'm still not sure whether that thing should be there... - DVdm (talk) 08:49, 19 January 2011 (UTC)[reply]
Here is the article in October, before a string of intense editing by Antichristos (and anonymous editors that are probably Antichristos). The old version, though not perfect, seems a lot better to me. Antichristos seems to subscribe to fringe ideas, for example he/she apparently thinks that gravitational radiation is nonsense. I suggest restoring the October version...and carefully double-checking Antichristos's contributions to any other articles... --Steve (talk) 09:05, 19 January 2011 (UTC)[reply]
At least it looks better. By the way, something similar might be happening in article Action at a distance (physics) (edit | talk | history | protect | delete | links | watch | logs | views). It contained (or still contains) a copy of what was added here (See Talk:Speed of gravity#Word-for-word copy of another article) - DVdm (talk) 09:34, 19 January 2011 (UTC)[reply]
Gravitational radiation is not nonsence. But the idea of its detectability is indeed nonsence. See this: The search for gravity waves (Paul Davies is one of the world's top cosmologists) - Antichristos (talk) 10:04, 19 January 2011 (UTC)[reply]
I've removed the second paragraph, as being unnecessarily confusing and constituting original research (I also think that it is misleading and irrelevant to the article, since Antichristos seems to confuse detecting "classical" gravity waves with detecting individual gravitons, e.g. misunderstanding Davies' point). In the course of this it occurred to me that the last section of the article, on the speed of of gravity in general relativity, needs some attention too, preferably from someone who knows more about it than I do (I am a mathematical condensed matter physics type). Rafaelgr (talk) 10:44, 19 January 2011 (UTC)[reply]
If the average Compton wavelength of the gravitons is 1 billion light years, it does not matter whether you detect a single graviton or a billion of gravitons—in both cases, the signal will arrive instantaneously. Antichristos (talk) 11:28, 19 January 2011 (UTC)[reply]
1) Wavelength has nothing to do with propagation speed.
2) Even if the average wavelength of gravitons was 1 billion lightyears (which seems to be a novel conclusion of the Antichristos) you would still be able to detect gravitational waves of shorter wavelengths.
The Compton wavelength of any quantum, be it a proton, an electron, a photon or a graviton,[1] is expressed as λ = hc/E and depends only on the quantum's energy (E). The universe's average photon is bluish-green,[2] which means that its energy (E = fh) is about 7×1014 h,[3] while its Compton wavelength is on the order of 10−15 light-seconds. Since the graviton is, on average, 1040 times weaker than the photon,[4] the Compton wavelength of the average graviton is 1040 times larger than the Compton wavelength of the average photon. Thus, the Compton wavelength (the radius of nonlocality) of the average graviton is about 1025 light-seconds, whereas the radius of the observable universe is only about 4.32×1017 light-seconds (13.7×109 light years). Since the Compton wavelength of the average graviton is about 2×107 times larger than the radius of the visible universe, any claims of having detected gravitational radiation or measured the "speed of gravity" are false.[5][6]
The Compton Wavelength of the "average graviton" is irrelevant as long as there are enough higher-energy gravitons around. If we accepted your argument, we'd also have to conclude that gamma ray telescopes are impossible because the average photon is blue-green. Rafaelgr (talk) 13:19, 19 January 2011 (UTC)[reply]
In relativistic quantum theory, a system cannot be localized to a precision better than its Compton wavelength,[7] expressed as λ = hc/E = c/f.
At f = 1 Hz, a quantum's energy (E = fh) is equal to h (the breakeven point between wave-likeness and particle-likeness), while the quantum's Compton wavelength (the radius of nonlocality, instantaneous propagation) is 1 light-second (300 thousand kilometres). According to the theory of relativity, superluminal propagation is propagation into the past. Therefore:
Conclusion:
  1. Gravitoelectromagnetic waves, whose frequencies are below 1 Hz, are undetectable.[10][11]
  2. Gravitoelectromagnetic waves, whose frequencies are above 1 Hz, do not exist. - Antichristos (talk) 13:35, 19 January 2011 (UTC)[reply]
This argument is (a) unclear and (b) apparently unrelated to your previous argument. I would ask where it is spelled out in more detail, except that it also does not address my main contention, which has consistently been that your main edits are WP:OR. Are you familiar with the Wikipedia policy on original research?Rafaelgr (talk) 13:43, 19 January 2011 (UTC)[reply]
When the average Compton wavelength of the gravitons is 300 thousand kilometres, it does not matter whether one detects the velocity of a single graviton or the group velocity of a myriad of gravitons—in both cases, the signal will arrive to both arms of the interferometer simultaneously. - Antichristos (talk) 14:08, 19 January 2011 (UTC)[reply]
The current version is full of synthesis. I'm reverting to the vastly superior version of August.TimothyRias (talk) 12:54, 19 January 2011 (UTC)[reply]
Note: user:Antichristos has broken WP:3RR by reverting me again. I've restored my revert. (Which places me at 3 reverts, so I'm done for today, could somebody else watch the situation?TimothyRias (talk) 13:29, 19 January 2011 (UTC)[reply]
Afaics the last paragraph is definitely severely wp:overlinked, and I suspect that the closing words of the last paragraph ("not even false") are inappropriate as in wp:synt. DVdm (talk) 10:57, 19 January 2011 (UTC)[reply]
OK, I will amend it. Antichristos (talk) 11:05, 19 January 2011 (UTC)[reply]

Note. An internal search reveals that we now have 5 articles with recently duplicated content: "In relativistic quantum theory, a system cannot be localized..."

  1. Article Gravitational wave (edit | talk | history | protect | delete | links | watch | logs | views) (see this string of edits )
  2. Article Speed of gravity (edit | talk | history | protect | delete | links | watch | logs | views)
  3. Article Action at a distance (physics)# (edit | talk | history | protect | delete | links | watch | logs | views)
  4. Article Negentropy (edit | talk | history | protect | delete | links | watch | logs | views)
  5. Article Nonlocality (edit | talk | history | protect | delete | links | watch | logs | views)

All content was added by user Antichristos (talk · contribs). Is this appropriate? DVdm (talk) 14:28, 19 January 2011 (UTC)[reply]

References

  1. ^ Davies, P. C. W. (1979). The forces of nature. Cambridge University Press. p. 116. Retrieved 2 Dec 2010.
  2. ^ The Universe is turquoise, say astronomers New Scientist, 10 January 2002
  3. ^ Aksoy, Pelin; DeNardis, Laura ♦ Information technology in theory Cengage Learning, 2007, p. 184
  4. ^ Daintith, John; Rennie, Richard (2005). The facts on file dictionary of physics. Market House Books. p. 124. Retrieved 2 Dec 2010.{{cite book}}: CS1 maint: multiple names: authors list (link)
  5. ^ Davies, P. C. W.The search for gravity waves CUP Archive, 1980, p. 129
  6. ^ When the average Compton wavelength of the gravitons is 1 billion light years, it does not matter whether one detects the velocity of a single graviton or the group velocity a myriad of gravitons—in both cases, the signal will arrive instantaneously.
  7. ^ Ji, Xiangdong (2004). "Viewing the proton through "color" filters". In Boffi, S.; Ciofi degli Atti, C.; Giannini, M. M. (ed.). Perspectives in hadronic physics: 4th international conference held at ICTP, Trieste, Italy, 12-16 May 2003. p. 24. {{cite book}}: |access-date= requires |url= (help); External link in |chapterurl= (help); Unknown parameter |chapterurl= ignored (|chapter-url= suggested) (help)CS1 maint: multiple names: editors list (link)
  8. ^ Corning, Peter A. ♦ Holistic Darwinism: synergy, cybernetics, and the bioeconomics of evolution University of Chicago Press, 2005, p. 340 (Since the gravitational field propagates into the past, its entropy decreases with time.)
  9. ^ "McGraw-Hill Dictionary of Scientific and Technical Terms". Retrieved 2 Dec 2010.
  10. ^ Davies, P. C. W.The search for gravity waves CUP Archive, 1980, p. 129
  11. ^ When the average Compton wavelength of the gravitons is 300 thousand kilometres, it does not matter whether one detects the velocity of a single graviton or the group velocity of a myriad of gravitons—in both cases, the signal will arrive to both arms of the interferometer simultaneously.