Wikipedia talk:WikiProject Physics/Archive January 2011

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)

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:

• Advances in Physics
• American Journal of Physics
• Annalen der Physik
• Applied Physics (A, B)
• Applied Physics Letters
• Astronomy and Astrophysics
• Astrophysical Journal (Letters)
• Australian Journal of Physics
• Canadian Journal of Physics
• Classical and Quantum Gravity
• Earth and Planetary Science Letters
• EPL
• European Journal of Physics
• European Physical Journal (A, B, C, D, E, H, ST, AP, Conferences)
• Faraday Discussions
• Faraday Transactions
• Japanese Journal of Applied Physics
• Journal of Experimental and Theoretical Physics
• Journal of Fluid Mechanics
• Journal of High Energy Physics
• Journal of Mathematical Physics
• Journal of Optics
• Journal of the Optical Society of America (A, B)
• Journal of Physics (A, B, C, D, E, F, G, CM, CS)
• International Journal of Modern Physics (A, B, C, D, E)
• Iranian Journal of Physics Research
• Iraqi Journal of Physics
• Monthly Notices of the Royal Astronomical Society
• Nature (Materials, Photonics, Physics)
• Nuclear Instruments and Methods in Physics Research
• Nuclear Physics (A, B, Proceedings Supplements)
• Nuovo Cimento (A, B, C, D, Supplemento, Lettere, Rivista)
• Optics Letters
• Philosophical Magazine
• Physica (A, B, C, D, E)
• Physica Status Solidi (A, B, C, RRL)
• Physical Review (A, B, C, D, E, Focus, ST AB, ST PER, Letters)
• Physics Reports
• Physics Today
• Planetary and Space Science
• Proceedings of the National Academy of Sciences
• Proceedings of SPIE
• Progress of Theoretical Physics
• Reports on Progress in Physics
• Review of Scientific Instruments
• Reviews of Modern Physics
• Science
• Space Science Reviews
• Ukrainian Journal of Physics
• Uspekhi Fizicheskikh Nauk

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)

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)

This could help: Wikipedia:WikiProject Physics/Taskforces/BPH/Publications/Popular_pages. Headbomb {talk / contribs / physics / books} 22:00, 2 January 2011 (UTC)

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)

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)

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)

Adinkras

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)

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

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)

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)

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)

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)

Tracking link: Nutku-Halil solution -- Chronulator (talk) 17:06, 16 January 2011 (UTC)

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)

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)

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)

Wikipedia talk:WikiProject Biography/Science and academia#Samo Stanič

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)

Speed of gravity

Being bold and archiving this. SPI and cleanup are already being handled, and this page is not the place to teach a problem-editor about QM, especially if they don't want to learn.
The following discussion has been closed. Please do not modify it.
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) 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) 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) 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) 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) 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) 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) 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, is expressed as λ = hc/E and depends only on the quantum's energy (E). The universe's average photon is bluish-green, which means that its energy (E = fh) is about 7×1014 h, 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, 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. 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) In relativistic quantum theory, a system cannot be localized to a precision better than its Compton wavelength, 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: A relativistic wave, whose frequency is above 1 Hz, begins its second period in the future; the third period, still further in the future, and so on. Such a wave is an electromagnetic wave; in its quantum—the photon—the particle-like magnetic phase dominates over the wave-like electric phase. A relativistic wave, whose frequency is below 1 Hz, begins its second period in the past; the third period, still further in the past, and so on. Such a wave is a gravitoelectromagnetic wave; in its quantum—the graviton—the wave-like electric phase dominates over the particle-like magnetic phase. Conclusion: Gravitoelectromagnetic waves, whose frequencies are below 1 Hz, are undetectable. Gravitoelectromagnetic waves, whose frequencies are above 1 Hz, do not exist. - Antichristos (talk) 13:35, 19 January 2011 (UTC) 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) 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) 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) 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) 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) OK, I will amend it. Antichristos (talk) 11:05, 19 January 2011 (UTC) I do not see why you-all are going on about the Compton wavelength. What matters for detection of classical waves is the actual wavelength $\lambda ={c \over \nu }\,$ which for a close binary star would be shorter than a light-year, not longer than the diameter of the observable universe. JRSpriggs (talk) 11:07, 20 January 2011 (UTC) But the formula for the Compton wavelength is the same: $\lambda ={c \over \nu }\,$. See for yourself: Compton_length#Relationship_between_the_reduced_and_non-reduced_Compton_wavelength So, what is the difference? (LOL. Are you really so clueless?) According to you, the wavelength for a close binary star would be "shorter than a light-year." It means that the frequency of such a field would be much lower than 1 Hz. But the energy of a quantum (E = fh) cannot be lower than h, which is measured as energy per second. A field, whose f is less than 1 Hz, is not quantized, because its quantum's energy per second would be less than h. Such a field is a purely wave-like nonlocal entity known as the quantum gravitational potential, the quantum potential, or the wavefunction. Since it is nonlocal, it does not even need to propagate. So, what speed are you going to measure? LOL. - 91.122.1.73 (talk) 07:49, 21 January 2011 (UTC) You should not talk about cluelessness. The frequency ν in my formula is the reciprocal of the orbital period (less than one year for a close binary star) since it is the relative positions of the stars which determines the phase of the wave. (The frequency might have to be doubled for the quadrupole moment of gravitons as opposed to the dipole moment of photons.) Multiplying that period by the speed of light gives a distance less than one light-year. The closer two black holes or neutron stars are to each other the stronger the signal would be, so it is the close binaries which would be the main source of radiation which we might hope to detect someday. Quantum mechanics does not invalidate this kind of classical reasoning. Indeed in such cases, the fact that a classical gravity wave may be composed of gravitons can safely be ignored. JRSpriggs (talk) 06:54, 22 January 2011 (UTC) The concept of a radiation, whose frequency is less than 1 Hz, defies the main tenet of quantum mechanics—the Planck postulate—according to which, a quantum's energy per second cannot be less than the Planck constant. A field, whose f is less than 1 Hz, is not quantized, because its quantum's energy per second (E = hf) would be less than h (which too is measured as energy per second). Such a field is a purely wave-like nonlocal entity known as the gravitoelectric field, the quantum gravitational potential, the quantum potential, or the wavefunction: The vacuum is really an expression of the continuous or noncountable nature of mass-energy (‘mass’, as the source of gravity). Continuity, as we will see, automatically makes mass-energy unidimensional and unipolar. <...> It is also responsible for quantum mechanical nonlocality and the instantaneous transmission of the static gravitational force—though not the acceleration-dependent inertial or GTR component, or the inertial reaction force that we actually measure in systems with localised mass (and with which gravity is often confused). —Rowlands, Peter ♦ The Nilpotent Dirac Equation and its Applications in Particle Physics p. 10 Any field, whose frequency is below 1 Hz, is a gravitoelectric field. Any field, whose frequency is above 1 Hz, is an electromagnetic field. Thus, a hypothetical binary, making more than 1 revolution per second, would emit low-frequency electromagnetic radiation, also known as gravitoelectromagnetic radiation. One final thought, Spriggs. In the Revision History, your reply is tagged as "ignore quantum mechanics," despite the fact that we are talking about gravitomagnetism. This is very telling. - 95.55.112.204 (talk) 11:02, 22 January 2011 (UTC) Status Note. An internal search reveals that we now have 5 articles with recently duplicated content: "In relativistic quantum theory, a system cannot be localized..." Article Gravitational wave (edit | talk | history | protect | delete | links | watch | logs | views) (see this string of edits ) Article Speed of gravity (edit | talk | history | protect | delete | links | watch | logs | views) Article Action at a distance (physics) (edit | talk | history | protect | delete | links | watch | logs | views) Article Negentropy (edit | talk | history | protect | delete | links | watch | logs | views) 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) For obvious reasons—see edit summary— I have reverted this most recent string of edits on Speed of gravity and left a third level warning on user talk page. DVdm (talk) 18:36, 19 January 2011 (UTC) After this edit was reverted once more, I have opened an edit warring report here. DVdm (talk) 20:14, 19 January 2011 (UTC) Antichristos (talk · contribs) says: At f = 1 Hz, a quantum's energy (E = fh) is equal to h (the breakeven point between wave-likeness and particle-likeness). Right there he's into complete balderdash, as it predicts that the point where particle and wave characteristics predominate, depends on what length of time we have chosen for our "second." He says it's one cycle per second. Why not one cycle per minute? In any case 100 cycle per second radiowaves really do not have much particle-like character. Antichristos is obviously a perveyor of crank physics. I urge treatment of his contributions as such. SBHarris 23:22, 19 January 2011 (UTC) Antichristos is absolutely right. The energy of a quantum (E = fh) cannot be lower than h, which is measured as energy per second. A field, whose f is less than 1 Hz, is not quantized, because its quantum's energy per second would be less than h. Such a field is a purely wave-like nonlocal entity known as the quantum gravitational potential, the quantum potential, or the wavefunction. - 91.122.1.73 (talk) 07:39, 21 January 2011 (UTC) Hey-- Antichristos doesn't even appear to know that h isn't in units of energy, but rather action (E*t or p*x). Saying that the energy of a quantum cannot be lower than h, is nonsense on the face of it. E can even be lower than hf in bound systems, as in the zero point energy of vibration, which is hf/2. In unbound systems, there are no quantum restrictions, and the energy of free particles can be anything you like-- as little or as large as you like, and without any quantum restrictions. In bound systems these come from E*t restrictions (measurement time is limited) or p*x restrictions (confinement length x is limited). Not from h. SBHarris 07:34, 22 January 2011 (UTC) The energy of a quantum (E = fh) is the energy per second. Also, bound systems are completely irrelevant here—the talk is about gravitational radiation. You are a waste of Time. - 95.55.112.204 (talk) 10:47, 22 January 2011 (UTC) Don't call me a waste of time when you screw up your simple units. Ef and h have units of energy TIMES time = energy-sec, not energy/sec. There is no "PER". Energy PER second is a unit of power. Planck's constant does not have units of power-- again it has units of action. How do you expect to be taken seriously when you cannot even come to grips with freshman physics 101? SBHarris 16:37, 22 January 2011 (UTC) In the English language, per means "for each; for every," but not "divided by" or "multiplied by." Accordingly, the Planck constant is expressed in joules per second or ergs per second (i.e., as energy per second): The Structure and Properties of Matter Astronomy: a textbook Illuminating engineering A comprehensive treatise on inorganic and theoretical chemistry Foundations of short wave therapy Molecular radiations Atomic Medicine Philips Technical Review Restricting the use of per to the meaning "divided by" is a relatively recent recommendation of the International System of Units (SI): "In both English and in French, however, when the name of a derived unit is formed from the names of individual units by multiplication, then either a space or a hyphen is used to separate the names of the individual units: pascal second, or pascal-second." This rule is artificially created, but since all school textbooks have adopted it, it should be followed. — 91.122.87.244 (talk) 19:09, 22 January 2011 (UTC) Give me a break. You can't do anything better than texts from 1935-1969? English and physics are perfectly clear: miles per hour means miles/hour. In any case, for h is in joule*sec (6.626...×10−34 J*sec), and frequency of 0.1 Hz, your energy is merely 6.626 x 10-35 joule. The Heisenberg principle says that for measurement times of 10 seconds like this, the energy uncertainty must be (on the order of) this large. SBHarris 23:04, 22 January 2011 (UTC) Antichristos is on a 72 hr block. Doubtless he'll be back. -- cheers, Michael C. Price talk 15:00, 20 January 2011 (UTC) There are more articles with problems due to edits by Antichristos: One-electron universe does not even mention its subject any more. -- Crowsnest (talk) 15:30, 20 January 2011 (UTC) How many ips did they edit under as well? I'm pretty sure some ip edits to those articles were by Antichristos too. It would make it easier to figure out what to look at and very probably revert. Dmcq (talk) 15:46, 20 January 2011 (UTC) Note that everything written by IP 89.110.4.94 (talk · contribs) in One-electron universe, by 89.110.20.164 (talk · contribs) in Speed of gravity, and by 89.110.9.221 (talk · contribs) in Action at a distance (physics), and no doubt many more IPs elsewhere, was written by the same author before they signed up for a user name. In this comment Antichristos was referring to himself in the third person ("its author"). DVdm (talk) 15:49, 20 January 2011 (UTC) It looked like Thesis, antithesis, synthesis was original research so I've reverted it to a much earlier version.--Physics is all gnomes (talk) 16:42, 20 January 2011 (UTC) Antichristos just made an not-logged edit as 89.110.14.26 (talk · contribs) and removed part of Action at a distance (physics). Technically, this is wp:block evasion. Can anyone have a look at whether this was indeed "his" content and whether it should be removed? DVdm (talk) 19:12, 20 January 2011 (UTC) The IP edit does appear to be in the style of Antichristos. The IP range is too large to block (it's a /18). I'm thinking that Antichristos's current block should be extended to a month, and all the articles named above should be semiprotected. Anyone who has knowledge about these topics should consider reverting his edits, I believe. EdJohnston (talk) 19:30, 20 January 2011 (UTC) I have left short messages on both talk pages. I think that a large part of the edits have already been reverted, including perhaps (?) the part he just removed—see my previous cmt. DVdm (talk) 19:40, 20 January 2011 (UTC) It may be Antichristos is a sock of indef blocked Systemizer (talk): They have similar interests (given the small number of their contributions). After the indef blocking of Systemizer and before Antichristos appeared the same IP-range as mentioned by EdJohnston was active on these pages. -- Crowsnest (talk) 22:22, 20 January 2011 (UTC) I'll add a request for a sockpuppet investigation to Wikipedia:Sockpuppet investigations/Systemizer, I'm pretty sure they're all the same person. Dmcq (talk) 22:47, 20 January 2011 (UTC) References

Holographic principle

There's a slow-motion edit war in progress at Holographic principle (edit | talk | history | protect | delete | links | watch | logs | views), focusing around who came up with the concept, if I understand correctly. More eyes would be helpful, as both editors appear to be in "I'm right" mode. --Christopher Thomas (talk) 16:37, 22 January 2011 (UTC)

This edit war is still going on. Could a third or fourth party please take a look at the dispute? This should have gone to the talk page long ago, but it's stayed in revert-boomerang mode for close to a week now. --Christopher Thomas (talk) 19:09, 24 January 2011 (UTC)

Action dimensions

There is one thing Antichristos has brought up which I think is interesting - he produced a load of references saying Plancks constant is in terms of ergs per second whereas it is actually erg seconds. The article here is correct but have people come across this sort of mistake afflicting other units and what do they do when a contributor sticks in a citation with a mistake like that? Dmcq (talk) 21:18, 22 January 2011 (UTC)

Did you look at the dates? Two are from 1935, a couple from the 40's and 50's, and the latest one is a medical text from 1969. Through the magic of Google-books Antichristos has managed to "do" some electronic copy-editing on a few texts which are from the era where electronic copy-editing didn't exist! So these errors slipped through. Big deal.They are all wrong. The meaning of "per" in English, and specifically in physics, is "divided by." As in miles per hour = miles/hr. This was true even in 1935 and it is certainly not true that the language has changed since then.

The problem with thinking that h is a unit of energy/time is that it gives us just the sort of problem Antichristos is stuggling with. That would imply that power can be only so small, and no smaller. Instead, Planck (actually Heisenberg, working with the implications of both Planck and de Broglie) postulates that action changes can be no smaller than (equal to or larger than) h/4π. But action is the product of energy and time, or energy and 1/frequency. If 1/frequency is larger than 1 in your units (1/0.1 Hz = 10 seconds) then that means E is merely h/(10 seconds). That's a very small energy, but it's a perfectly possible energy. There is no lower limit on energy. SBHarris 22:53, 22 January 2011 (UTC)

I tried duplicating what he did by doing a google with '"ergs per second" planck', I got a few examples of the mistake but most even with this search gave the correct units and were using ergs per second for something reasonable like how much energy the sun radiated. I think he must have gone to some trouble to ignore the correct versions. Dmcq (talk) 23:22, 22 January 2011 (UTC)

Flavour (particle physics)

The box in the top right corner lists several quantum numbers as "flavour quantum numbers". Whereas I agree with isospin, charm, strangeness, topness and bottomness being flavour quantum numbers, I am wondering whether baryon/lepton number, weak isospin, electric charge and X charge should indeed be listed as flavour quantum numbers. On the other hand, the leptonic e, μ, τ flavours are missing. Is there any reference stating that the baryon number, ... are indeed "flavour" quantum numbers? --Dogbert66 (talk) 17:05, 23 January 2011 (UTC)

As a note, the leptonic numbers are covered in the lepton number article. I don't have a particularly strong opinion on how to organize that flavour quantum number (FQN) navbox, but I think all links currently present in the FQN navbox should remain there. A re-organization may be warranted, but I don't have any specific suggestions myself. Headbomb {talk / contribs / physics / books} 21:03, 23 January 2011 (UTC)

Perhaps put ones that aren't directly related to flavour into a separate heading in the sidebar? The logical place for an extended discussion of this would be at Template talk:Flavour quantum numbers. --Christopher Thomas (talk) 21:20, 23 January 2011 (UTC)

Thanks for the responses. I corrected the template in the way suggested by Christopher Thomas. This topic can be closed. --Dogbert66 (talk) 09:23, 24 January 2011 (UTC)

Unfortunately there is no consistence definition of what a flavor quantum number is in the literature. One definition I find particularly useful is to use the word flavor to refer to quantum numbers associated with global symmetries only (sometimes also called accidental symmetries). That criteria has the merit of associating the term with something that is actually physically meaningful. According with that criteria Baryon number and Lepton number are indeed flavor numbers while weak isospin, weak hypercharge and electric charge are not. Dauto (talk) 18:47, 30 January 2011 (UTC)

SIMPLE

A new user, Esdacosta (talk · contribs), has recently attempted to make an addition to Dark matter (edit | talk | history | protect | delete | links | watch | logs | views) to mention a detector he's writing a page about (presently at User:Esdacosta/SIMPLE (dark matter)). From what I can find online, this is a legitimate dark matter detection experiment, and the user in question may actually be one of the researches involved in the project. I've suggested that they come here for advice and assistance for creating a properly-sourced article (at SIMPLE (dark matter)) and for adding links to it on appropriate pages. They appear to be acting in good faith; let's help them with this if possible. --Christopher Thomas (talk) 00:45, 29 January 2011 (UTC)

I see that we have changed our policy on OR and COI. ;) JRSpriggs (talk) 07:34, 29 January 2011 (UTC)

Conflict of interest does not prevent a participant in the experiment from helping with an article on it. They just have to be open and careful. It will not be original research if the experiment has been published, which it seems it has been, and preferably then mentioned in a review article. Editors like this need to be encouraged, not driven away by mention of OR and COI. --Bduke (Discussion) 07:52, 29 January 2011 (UTC)

I'll second what Bduke said. WP:OR says that they can't be trying to publish their results on Wikipedia. They are not doing so. They are trying to document material that has been published in reputable venues elsewhere. WP:COI says that they should seek external opinions to confirm that what they're writing is neutral, and that's exactly what I've suggested they do here. In what way do you feel that either of these policies is being violated? --Christopher Thomas (talk) 08:06, 29 January 2011 (UTC)

I'll third it. People involved with experiments aren't usually evil when it comes to creating articles on them. It's a problem when they're saying stuff like This experiment is the most awesome experiment in the world and will crush all other experiments on the subject, muahahahah! Especially that other one whos data is utterly useless compared to ours. Also look at my abs! Aren't they sexy? This is obviously not what is happening here, it's just a basic description of the experiment. Headbomb {talk / contribs / physics / books} 12:02, 29 January 2011 (UTC)

Just because it has been published does not mean that it is notable. Xxanthippe (talk) 21:31, 29 January 2011 (UTC).

The SIMPLE experiment is notable, otherwise I wouldn't have heard of it before :). This experiment has become a lot more prominent recently, because it has just reported new limits on WIMPS, see here. It won't be long before new theory papers will appear that include the limits from SIMPLE. Count Iblis (talk) 00:28, 30 January 2011 (UTC)

Publication in serious journals has been the yardstick for notability for most of the scientific articles I've seen here. Per WP:NOTPAPER, the barrier for inclusion in Wikipedia is pretty low. The policy to watch out for is WP:UNDUE - giving less noteworthy research the appearance of undue weight in the scientific community. That does not seem to be what is going on here, so I fail to see the problem with creating an article about this detector. --Christopher Thomas (talk) 06:58, 30 January 2011 (UTC)

Hello everyone. Yes I am new to this and am just updating the dark matter problem. In fact, the SIMPLE dark matter experiment has been around since 1998. It is a small group (based from Portugal). It has many publications on dark matter, superheated droplet detectors, etc. Although small, this direct detection experiment has presently the best limit on the Spin-dependent sector. This is not stated in my talk! The talk serves to inform the global community, since the dark matter obviously knows about SIMPLE, I hope! thank you! I will update the most I can. esdacosta —Preceding undated comment added 20:40, 30 January 2011 (UTC).

Relativity criticism...

I'm not sure, if it's a good idea to move the article User:D.H/test (translated by me from German) to Criticism of relativity theory. Maybe it would cause some trouble by anti-relativity cranks... Opinions? --D.H (talk) 21:46, 30 January 2011 (UTC)

Perhaps your article could be merged into History of special relativity.

It probably would attract cranks, but if it has accurate and notable content (which it does), then that should not deter us from adding it to Wikipedia. JRSpriggs (talk) 09:11, 31 January 2011 (UTC)

I also thought about merging it into the History article. However (except the section on electromagnetic worldview), most of those criticism played no essential role in the development of relativity, so I think it would give Undue Weight to some of them, if they were put into the history article. (Anyway, I now created Criticism of relativity theory). Let's see what will happen... --D.H (talk) 09:42, 31 January 2011 (UTC)

Looks like an excellent article. I had a look at the original before, and wondered why we didn't have its counterpart here. Well done on the translation. I think it deserves its own article—i.m.o. merging it into the history article would produce overload. And yes, it most probably will attract, but the article is solidly sourced, so that should not be a major problem (touching wood). - DVdm (talk) 09:51, 31 January 2011 (UTC)