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August 7

AMOC and NAC

What is the relation between the Atlantic Meridional Overturning Circulation and the North Atlantic Current? Neither article refers to the other, but they seem to be closely related phenomena.  --Lambiam 20:03, 7 August 2021 (UTC)

Those articles don't even have a mutual "see also" entry. It looks to me as though there would be a case for merging the articles, but I know nothing about the subject and suggest you raise it on the respective talk pages.--Shantavira|^{feed me} 11:02, 8 August 2021 (UTC)

I have left a request for assistance at Wikipedia talk:WikiProject Meteorology. Alansplodge (talk) 11:48, 8 August 2021 (UTC)

August 9

Why does a laptop attracts red ants not black ants?

From here, why does a laptop attracts red ants not black ants? I didn't find any useful information here I too faced same problem with that red ants. Rizosome (talk) 14:46, 9 August 2021 (UTC)

That link does not say that red ants are particularly attracted to laptops NOR does it say that black ants are not attracted to them. It is just one person saying that their one laptop had been infested by red ants. It should be noted that there are thousands of different ant species, and some are red and some are black and without knowing which we are talking about, it would be difficult to make any useful statements about why one particular species might infest one particular lap top. --Jayron32 15:16, 9 August 2021 (UTC)

I studied ants at one point. I found that the red ants ate more than the black ants. I could never determine why for sure, but I hypothesized that my experiment had more red ants than black ants. ←Baseball Bugs ^{What's up, Doc?} carrots→ 16:03, 9 August 2021 (UTC)

If the laptop owner is from Britain, there are only two species of ant that are widely encountered; the black garden ant (Lasius niger), and the common red ant Myrmica rubra. The 50 or so other species all require specialised habitats and are much less likely to be found - see list of ants of Great Britain. But who knows in this case? Alansplodge (talk) 12:09, 10 August 2021 (UTC)

A strict experimental rubric seems somewhat lacking here. So I suspect the result of this single trial has been hideously inflated! So were these ants in the laptop or in the case!? (could be worse). Martinevans123 (talk) 12:17, 10 August 2021 (UTC)

Reduced Risk of Reinfection with SARS-CoV-2 After COVID-19 Vaccination — Kentucky, May–June 2021

Can someone please help me to understand this article in layman's terms?[1] It says that unvaccinated COVID survivors are twice as likely to get reinfected than COVID survivors who get vaccinated. But what does "twice as likely" actually mean? If, for example, the reinfection rate of the former is 93% and 96% for the latter, isn't that "twice as likely"? Is it possible to sus out the actual reinfection rates from this article? A Quest For Knowledge (talk) 20:04, 9 August 2021 (UTC)

This is called odds_ratio. Ruslik_Zero 20:34, 10 August 2021 (UTC)

August 10

Proving the relativistic formulas (that use Gamma factor), of momentum, or of mass:

I wonder if it's possible to prove the well known relativistic formulas: m=γmo, p=γmoV, without relying on the concept of energy as used in Relativity theory, and mainly without relying - on the equivalence of energy and mass - nor on the assumption about the four-vector of energy and momentum.

I do allow, though, to use Newton's laws, along with the two basic assumptions of Special Relativity about the invariance - of light speed - and of laws of Physics. I may permit additional assumptions as well, provided that they are really "intuitive" or at least not as "heavy" as the assumptions mentioned above about energy. 185.120.124.50 (talk) 08:17, 10 August 2021 (UTC)

The only real alternative to energy as a concept is action, and if you thought energy was non-intuitive and "heavy", oh boy. But you asked for it... The equivalent of "conservation of energy" using action is the principle of least action and general relativity can be derived using the concept of Einstein–Hilbert action. --Jayron32 10:51, 10 August 2021 (UTC)

I suspect we don't understand each other. I haven't rejected the idea of using principles about energy, nor of using the conservation of energy - as it's acknowledged in Newton's Mechanics as well. I have only rejected the idea of using the concept of energy as used in Relativity theory, like the equivalence of energy and mass, and like the four-vector of energy and momentum, and like the energy- momentum relation. 185.120.124.50 (talk) 11:12, 10 August 2021 (UTC)

I'm not sure why you've rejected those ideas. It's not like you get to pick and choose which parts of well-established scientific principles you get to "accept" and then expect everything that depends on them to work. --Jayron32 12:08, 10 August 2021 (UTC)

Oh. I don't reject anything on an ideological basis. It's only a logical game: I'm only asking if it's possible to logically prove the well known relativistic formulas (that use Gamma factor) of momentum or of mass, while only using - both Newton's laws (including the conservation of energy/momentum as used in Newton's Mechanics) and the two basic assumptions of Special Relativity about the invariance - of light speed - and of laws of Physics. It's also fine to use other intuitive assumptions, as long as they may be considered to be sufficiently "intuitive" by Newton. 84.228.238.42 (talk) 16:58, 10 August 2021 (UTC)

It seems like you're asking if General Relativity could be established as long as one never considers Special Relativity; for various reasons, I'm not sure that's possible. General Relativity starts with Special Relativity, and it generalizes it from inertial frames to accelerating frames. Mass-energy equivalence and the four vector are inextricable parts of SR. The important part of GR for our purposes is the Equivalence principle between gravitational and inertial mass; another key point is that while pre-Special Relativity physics had established that the speed of light was invariant, GR establishes that the spacetime path of light is also invariant (it follows a geodesic in curved space time.) In order to start to get at what much of General Relativity concludes, you really need those parts of Special Relativity you are discarding as a thought exercise. I'm not as strong in the mathematical end of this as most other people here, so it may be possible to do what you are asking, it just may require some really complicated work-arounds. But I doubt even that. --Jayron32 17:28, 10 August 2021 (UTC)

I'm quite amazed at what you ascribe to my question: Actually, it has nothing to do with General relativity: By "mass" I'm only referring to inertial mass. Further, as opposed to what you claim, I did (and still do) allow to use - at least the two basic assumptions of Special relativity, i.e. the invariance - of light speed - and of laws of Physics. 84.228.238.42 (talk) 18:49, 10 August 2021 (UTC)

But mass-energy equivalence is both an inseparable part of Special Relativity and a law of physics. You can't just pull at threads and not expect the entire blanket to not just unravel like that. --Jayron32 12:43, 11 August 2021 (UTC)

The Lorentz factor $\gamma$ was derived independently by FitzGerald and Lorentz in a conceptually Newtonian setting, as part of a theoretical explanation of the observed invariance of the speed of light. It appears in the formulas for momentum in special relativity, which extend the Lorentz transformations consistently to other physical quantities than just length and velocity. Presumably it is the simplest consistent extension, but perhaps it is even the only one.  --Lambiam 18:00, 10 August 2021 (UTC)

Yes, but the Lorentz factor itself comes after the Lorentz transformation, which deals with the four vector, one of the verboten concepts the OP wants to avoid invoking. No four-vector, no Lorentz transform, no Lorentz factor. --Jayron32 18:05, 10 August 2021 (UTC)

The original Lorentz transformations concerned only length and time. It all began with the length contraction formula, first formulated by FitzGerald in 1889, which already involved $\gamma$ (although FitzGerald did not use the symbol). The four vector came later, when it was realized that extensions were required for physical quantities involving other dimensions than length and time to have a consistent body of physical laws beyond the kinematics of bodies in free fall. What I do not know if there was a choice, or if all such extensions result in isomorphic sets of transformations. I suspect, though, that the choice was forced.  --Lambiam 08:41, 11 August 2021 (UTC)

You should be able to get there by considering a collision at low (nonrelativistic) velocities in the lab frame, boosting to a reference frame moving at relativistic velocity relative to the lab frame, and requiring momentum to be conserved in the moving frame. Any consideration of energy will only be in the lab frame, so you're not making assumptions about relativistic energy or mass, you're only requiring that they have the correct Newtonian limit at low velocity. You can find papers like [2] that do something along these lines. --Amble (talk) 20:54, 11 August 2021 (UTC)

August 11

Does hassocene or any super heavy molecule exist now that its been a few years?

And is ittime to update the page? — Preceding unsigned comment added by Blacephalon (talk • contribs)

I can't find anything, all publications I can find on it are proposals that it should have the same structure as other group 8 metal analogues, like ferrocene and osmocene, but near as I can tell it has never been synthesized. It is also very unlikely to be, as Hassium has, at BEST, a half-life of about 10-15 seconds, making the isolation of stable organometallic compounds of it difficult. Some compounds have been isolated, but they don't last long. --Jayron32 12:38, 11 August 2021 (UTC)

August 13

Sea level rise due to melting of all the ice on Antarctica

The sea level rise assuming that all the water gets distributed evenly over the oceans is about 58 meters. However, if the Antarctic ice were to completely melt, then the gravitational pull of the ice sheet on the water that currently causes a very large increase in sea levels near Antarctica, will also vanish. The question is then what the effect on the sea level will be if the Antarctic ice sheet were to completely melt on the sea level in Northern Europe and on the sea level near Antarctica. Count Iblis (talk) 00:18, 13 August 2021 (UTC)

There is a lot of doubt about how much the rise will be. See post-glacial rebound.41.165.67.114 (talk) 06:23, 13 August 2021 (UTC)

See here: https://www.whoi.edu/press-room/news-release/why-is-sea-level-rising-higher-in-some-places-along-u-s--east-coast-than-others 41.165.67.114 (talk) 06:38, 13 August 2021 (UTC)