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January 9

Element 172

Extended periodic table: "Element 172 (unseptbium) is expected to be a noble gas with chemical behaviour similar to that of xenon, as their ionization energies should be very similar (Xe, 1170.4 kJ/mol; element 172, 1090 kJ/mol). The only main difference between them is that element 172, unlike xenon, is expected to be a liquid or a solid at standard temperature and pressure due to its much higher atomic weight." However, due to the periodic trends, Uub is the 8th noble gas, and it should be more reactive than Og (the 7th noble gas), and it should have higher melting point and higher boiling point than Og, but Og is reactive and it is excepted to be a solid at standard temperature. 2402:7500:918:A8FE:A474:8A0A:804A:9C97 (talk) 06:58, 9 January 2024 (UTC)

Energy eigenvalues in the superheavy elements

You're not really comparing like with like, because relativistic effects mean that the late 8th period is a different situation from the late 7th period in terms of orbital energies and the order of filling. To oversimplify it: down the table, noble gases increasingly don't think they have a full shell because np_3/2-(n+1)s_1/2 gap gets smaller. (Ng⁺ monocations in excited states with energies under the first ionisation energy of the noble gas can populate (n+1)s for Kr, Xe, and probably Rn and Og, but not for Ne and Ar.) But by the time you hit element 172, this gap becomes negative, so it's really the np_3/2-(n+2)s_1/2 gap that now matters, and that's huge. You can kind of see what's going on in the figure to the right (although it doesn't have 10s there yet).

In the late 7th period, due to the spin-orbit interaction, the 7p subshell is split into one more stabilised p-orbital (7p_1/2) and one less stabilised p-orbital (7p_3/2). The split is so much that by the time 7p_3/2 fills, it's not actually that far from 8s in energy. 7s_1/2 is also quite stabilised by relativistic effects. So what happens is that Cn (6d¹⁰7s²) acts like a closed shell (more so than Hg), that Fl (7s²7p_1/2²) also acts like a closed shell (also more so than Hg), and finally Og (7s²7p_1/2²7p_3/2⁴) "thinks" it is a tetravalent element with four valence electrons and should be able to involve 8s in hybridisation.

Whereas in the 8th period, this happens to such an extent that by the time you get to elements in the 160s or so, 8s is already in the core, and so is 8p_1/2. Instead, 8p_3/2 is so destabilised that it ends up very close in energy to 9s and 9p_1/2. Consequently, the situation from elements 157–172 is that 7d_3/2, 7d_5/2, 9s_1/2, 9p_1/2, and 8p_3/2 are quite similar in terms of energy differences to the way 4d_3/2, 4d_5/2, 5s_1/2, 5p_1/2, and 5p_3/2 behave in the fifth period. On the other hand 10s_1/2 is much higher in energy, and in essence that's the next valence shell just like 6s_1/2 is for xenon. That makes 172 resemble a super-xenon.

(Obligatory caveat that we don't really know if elements that heavy will be stable enough to even call chemical elements.) Double sharp (talk) 09:04, 9 January 2024 (UTC)

If the reciprocal of the fine-structure constant is 299792458 rather than 137, then the physical properties and the chemical properties of the elements in the period 8 will be completely different? 2402:7500:918:A8FE:A474:8A0A:804A:9C97 (talk) 09:39, 9 January 2024 (UTC)

The higher the reciprocal of α, the weaker the electromagnetic interaction is between particles. So atoms would, to put it bluntly, instantly fly apart due to electromagnetism being very weak.

I do wonder how long a hydrogen atom would last if α = 1/c instead of around 1/137. Stoplookin9 (talk) 02:55, 10 January 2024 (UTC)

The fine-structure constant, being dimensionless, cannot be equal to 1/c, as that would have a dimenion of inverse velocity. By choosing different units of measurement, I could make the numerical value of c anything I like, including 1/α. PiusImpavidus (talk) 09:10, 10 January 2024 (UTC)

In the Hartree atomic units, the value of $c$ is $1/\alpha$. 2402:7500:901:720D:FC88:A133:EB79:3B45 (talk) 14:05, 12 January 2024 (UTC)

Denis Walsh on Evolution?

What is the current view of evolution biologies about the ideas of the university of Toronto professor Denis M. Walsh?
Is his view werth to consider it? 2A02:8071:60A0:92E0:D059:5B33:4DE5:1E8 (talk) 22:21, 9 January 2024 (UTC)

He is a philosopher of science or historian of science rather than a biologist. tgeorgescu (talk) 22:51, 9 January 2024 (UTC)

January 10

Neurotransmitters

Is there a neurotransmitter which has the opposite effect of dopamine and/or suppresses the release of dopamine? Also, is oxytocin synergetic with or antagonistic to dopamine, or neither? 2601:646:8080:FC40:3982:CA81:D9FD:A932 (talk) 03:41, 10 January 2024 (UTC)

Monoamine oxidase (MOA) break down dopamine and therefore has sort of the opposite effect by reducing dopamine levels. --CometVolcano (talk) 14:59, 13 January 2024 (UTC)

Thinking in that same direction, there are a bunch of factors that can upregulate the dopamine transporter, which would increase dopamine reuptake (clearing it from the synapse). DMacks (talk) 22:40, 13 January 2024 (UTC)

Thanks, but I was asking specifically about neurotransmitters, not enzymes. 2601:646:8080:FC40:B181:27B1:C710:220B (talk) 00:45, 16 January 2024 (UTC)

Sterile Surgery

Joseph Lister (and others) had pretty much proven that sterile techniques during surgery and childbirth saved lives. But he and the others met fierce resistance. In 1873 The Lancet, the leading medical journal, disparaged Lister and recommended his procedures not be followed. Who edited The Lancet at that time? Any ideas of his/its motivation--after all, rich people and their babies died of infections too. 24.72.82.173 (talk) 22:58, 10 January 2024 (UTC)

I saw the name Richard Beverly Cole listed at a few places online, which lead me to R. Beverly Cole. Sure enough, the article states: "In 1890, Cole registered his opposition to antiseptic injections in obstetrics before the obstetric committee of the Medical Society of the State of California, reasoning that deliveries had long been accomplished before the introduction of antisepsis." This was 17 years later, in 1890. Guy sounds pretty stubborn! Beach drifter (talk) 00:56, 11 January 2024 (UTC)

Cole never edited The Lancet. DuncanHill (talk) 01:25, 11 January 2024 (UTC)

I see now that the picture I was looking at was of The Western Lancet - https://www.flipkart.com/western-lancet-1873-vol-2-monthly-journal-devoted-medicine-surgery-collateral-sciences-classic-reprint/p/itm39c65d42bf025 Beach drifter (talk) 01:45, 11 January 2024 (UTC)

The Lancet in 1873 was edited by T. H. Wakley and James G. Wakley. DuncanHill (talk) 01:23, 11 January 2024 (UTC)

Slightly unrelated, I remember reading about how the innovation of anesthesia was spread to faraway continents in, say, two years, while disinfection took decades. According to this source, the reason was that anesthesia has a very visible benefit for both the surgeon and the patient, but disinfection does not. --Error (talk) 09:46, 12 January 2024 (UTC)

Resistance to Lister's methods seems to fall into two camps; one being those who saw nothing wrong with traditional techniques:

At the 1869 meeting of the British Medical Association in Leeds, the local senior surgeon Thomas Nunneley (1809–1870) launched a violent attack upon antisepsis. He outed himself as ultra-conservative, not just by denying the germ-theory of wound infections but also by misquoting the experience of local colleagues who had had some success with Lister’s methods. As Lister pointed out in his reply in the BMJ, Nunneley ‘dogmatically oppose[s] a treatment which he so little understands and which, by his own admission, he has not tried’.

The other group, such as Lawson Tait, were more enlightened and had acheived considerable improvements by means of other chemicals or simple hygene with soap and water; These approaches were also much less cumbersome, expensive and time-consuming than antisepsis using carbolic acid sprays, and thus better suited to busy practitioners and in emergency cases... Statistics were used to suggest that cleanliness was more successful than Listerism in preventing death.

See Statistics and the British controversy about the effects of Joseph Lister’s system of antisepsis for surgery, 1867–1890. Alansplodge (talk) 12:12, 12 January 2024 (UTC)

In Europe the dispute turned ugly Ignaz Semmelweis. 2A02:C7B:11B:9000:102:E620:5DF:9CB1 (talk) 15:42, 12 January 2024 (UTC)

January 11

Planck's Law and Kirchhoff-Clausius law

In § 7 Chapter II of "On the Law of the Energy Distribution in the Normal Spectrum; by Max Planck."[1], one reads:

"According to Kirchhoff-Clausius law, the energy of a temperature ϑ and the number of vibrations ν, when emitted by a black surface per unit of time into a diathermic medium, is inversely proportional to the square c² of the propagation speed."

I did not find this law in this form anywhere . Can anyone help me understand this sentence? Malypaet (talk) 22:59, 11 January 2024 (UTC)

Finaly I found it in "eight lecture at colombia" from Gutemberg project p35:

G. Kirchhoff, Gesammelte Abhandlungen, Leipzig, J. A. Earth, 1882, p. 594.[2] Malypaet (talk) 22:12, 13 January 2024 (UTC)

January 13

To what large is height hereditary?

To what extent is hereditary of height of a human body? 2A02:8071:60A0:92E0:1DF0:3298:75EF:4F08 (talk) 23:43, 13 January 2024 (UTC)

60-80%, according to molecular biologist Chao-Qiang Lai, "up to 80%", according to a "landmark" study. Clarityfiend (talk) 23:47, 13 January 2024 (UTC)

This is disputed, as these GWASes are inherently flawed, and with height there is maternal effects and even grandmaternal effects, which are nutrition-history-related. A better guess is 0%. Abductive (reasoning) 14:55, 14 January 2024 (UTC)

0% to 80% is a large ranche 2A02:8071:60A0:92E0:8F6:F3C6:49F3:5A10 (talk) 17:27, 14 January 2024 (UTC)

Personal observations: Other than abnormalities, like giantism or dwarfism, for example, height seems often to be a function of when youngsters experience their "growth spurt" or achieve physical maturity. The later it comes, the taller the individual tends to be. I would think that could be a function of genetics. But as Abductive points out, nutrition could figure into it too. ←Baseball Bugs ^{What's up, Doc?} carrots→ 20:15, 14 January 2024 (UTC)

But how could it be that some persons get some investigation on their bones and get called how hight they will growth? I've heared about this from persons who are actually quite hight and they get call it before puberty. 2A02:8071:60A0:92E0:90D:EB9E:AAEF:6E30 (talk) 21:45, 14 January 2024 (UTC)

Geneticists who estimate heritability are really not so naive as to be unaware of confounds such as maternal effects and of the effect of nutrition. One way to factor them out is to compare monozygotic and dizygotic twins: both sorts share the same environment if they grow up together, but monozygotic twins are 100% identical genetically, whereas dizygotic twins share only 50% of their genes. This and this are a couple of studies utilising this methodology. Another approach of disentangling genetics and environment relies on adoptions. The studies use large sample sizes and yield consistent results. Nobody should be claiming here that the heritability of human height is 0. JMCHutchinson (talk) 21:09, 14 January 2024 (UTC)

One of the main maternal effects is the size of the mother's uterus, which is affected by their height, their previous pregnancies, and their nutritional status at age 12 or so. One cannot use twins without thinking, as they share a uterus. Abductive (reasoning) 22:50, 14 January 2024 (UTC)

You can compare monzypotic and dizygotic twins. 2A02:8071:60A0:92E0:90D:EB9E:AAEF:6E30 (talk) 00:21, 15 January 2024 (UTC)

Yes, the shared uterus, like the shared socio-economic status, nutrition, etc., of twins is an advantage inherent in twin studies, not a problem with them. Twins largely share their environment, so what is left to explain inter-twin differences is noise (in the case of monozygotic twins) and noise + half their genes (in the case of dizygotic twins). JMCHutchinson (talk) 08:09, 15 January 2024 (UTC)

The articles Twin study, Heritability, and GWAS set out a number of very serious concerns. Anyway, it really depends on what the IP is trying to do with their question. Do they want the current estimate to tell people at parties? Or are they going to write a paper on it? Are they going to breed cows and need a number? Abductive (reasoning) 13:50, 15 January 2024 (UTC)

Agree completely. You should follow what the scientific papers say instead of someone who is wrong on the internet unless you have a very good reason to know otherwise. NadVolum (talk) 21:36, 14 January 2024 (UTC)

Basically, the 0% answer is what a graduate student's committee members will say to them if they propose relying on somebody else's GWAS for their thesis or for their career advancement. Abductive (reasoning) 22:50, 14 January 2024 (UTC)

There are other ways than just GWAS, right? 2A02:8071:60A0:92E0:90D:EB9E:AAEF:6E30 (talk) 00:20, 15 January 2024 (UTC)

I am not understanding Abductive's arguments, but GWAS (Genome-wide association study) is a side issue. GWAS articles, such as the one cited above by Clarityfiend, treat the heritability estimates from twin studies as a gold-standard value. They are hoping that their own independent estimates of heritability, based on statistical comparison between gene sequences (from whole genome sequencing) and height, reach the same ball-park figures. So far these estimates tend to be lower. Hypotheses to explain the discrepancy are many genes having small effects, rare genes having big effects, and interactions between different genes (all of which are difficult to detect statistically). Indeed with larger sample sizes and more sophisticated analyses the gap is closing. This is a general issue with GWAS of other traits also, so raw GWAS estimates of heritabilities are not yet considered reliable. JMCHutchinson (talk) 08:29, 15 January 2024 (UTC)

We're supposed to try and refer people to an appropriate Wikipedia aricle for questions like this, and there is one Human height. Not go in for pushing ones interpretation of how genetics works. Saying 0% is like saying anyone could have run as fast as Usain Bolt with the appropriate upbringing and training. Or at least coming towards that to except for some epigenetic, mitochondrial and prenatal effects. It's always the mothers fault they can't run that fast :-) NadVolum (talk) 14:43, 15 January 2024 (UTC)

A glance at this thread will reveal that I have shaded my meaning correctly throughout, and nobody is misled. Abductive (reasoning) 17:57, 15 January 2024 (UTC)

Shaded your meaning correctly? Pull the other one. NadVolum (talk) 18:17, 15 January 2024 (UTC)

Height is 100% hereditary. If your parents are three-dimensional, you will be too. AndyTheGrump (talk) 18:21, 15 January 2024 (UTC)

January 14

Could graphene ever replace macroscopic metal conductors in any home or car application?

It'd have to be stacked without increasing the ohm-meters too much, and I don't know if there's anything a middle-class person might own that could be improved by replacing some or all the macroscopic conductor with stacked graphene. Nanotech would have to get cheap enough to compete with "make the copper thicker". Could graphene ever replace wires that are thicker aluminum instead of copper for mass reasons?

Sagittarian Milky Way (talk) 16:32, 14 January 2024 (UTC)

One presumes you are referring to Ohm metres, not Ohmmeters. Mitch Ames (talk) 05:28, 15 January 2024 (UTC)

I don't know that you'd see a 1--1 substitute for simple loose copper wire, since that has important metallic properties that something mostly-graphene won't replicate, even if cheap and light. (Like, you couldn't just replace phone and electric catenary lines with some graphene material because it won't stretch. But there's an awful lot of electric and telecoms infrastructure that isn't dangling copper cable, including all the new big stuff.) But see a 2022-10-11 Caltech Weekly article on some of the flexible graphene structures they're making, including a graphene coating for copper traces on silicon. A more detailed technical review of stacking graphene is in Han et al 2021 if you want to try finding something of interest. SamuelRiv (talk) 06:43, 15 January 2024 (UTC)

Also an interesting 2014-09-02 StackX discussion on graphene conductivity notes that the practical gains aren't anywhere as huge as the hype (1.4 times more conductive, or 5.8 times compared by weight), even assuming you can make or engineer around the issue of needing near-perfect sheets. This as opposed to the possibility of using superconductive lines for either long-range transmission (EETimes 2022-07-07) or metro-area grids (Yang et al 2020) (also not as good as the hype at present). SamuelRiv (talk) 07:20, 15 January 2024 (UTC)

Oh -- airplanes! That'd probably be the case where everything from high-performance jets to home-built hobby kits would replace any metal wiring with some mostly-graphene substitute, even if it cost 100x more per meter, since the weight savings is so much, and it's all enclosed. (You can already just use powdered graphite as a conductor (there's an Instructable for making a weak conductive glue with it), but that's altogether not great.) So I'll instead guess sooner rather than later, anything that flies would have graphene wiring if some viable product is invented, even if it's much more expensive. SamuelRiv (talk) 02:18, 16 January 2024 (UTC)

January 15

Human body 5G emission

Using black body radiation, what is the power of what the human body emits in 5G frequencies, compared to a phone? Also, a 100W incandescent lightbulb? Zarnivop (talk) 10:04, 15 January 2024 (UTC)

This sounds potentially like a homework question.

The solution method is to integrate Planck's law over all space, but just for the frequency range of interest. You'll need to specify a surface temperature for a human being and the lightbulb, although the latter is easy to calculate from the power, given the Stefan-Boltzmann law. PianoDan (talk) 15:29, 15 January 2024 (UTC)

I am a bit old for homework. My children are, too. The surface temperature probably is ok with 34 Celsius. I have no idea about the lightbulb. Zarnivop (talk) 17:43, 15 January 2024 (UTC)!

It is much simpler to use Rayleigh–Jeans law for such low frequencies. So, we have for power $P$:

$P={\frac {2\pi k_{B}TS}{3c^{2}}}(\nu _{2}^{3}-\nu _{1}^{3})$

where $S$ is surface area of a human body (or bulb filament), $\nu _{2}$ and $\nu _{1}$ are upper and lower frequencies of the 5G band, $T\approx 300$ K (or 2500 K) and other parameter explained in the article. Ruslik_Zero 21:03, 15 January 2024 (UTC)

so 2×pi×1.38exp(−23)×(273+34)×1.9÷(3×(3 exp(8)^2))×(71 exp(6)-24.25 exp(6))

I got 8.76. 8.76 what?Zarnivop (talk) 01:27, 16 January 2024 (UTC)

Well everything would have to be in SI base units, power in watts but 8.76 watts from a human seems too big. Frequency would have to be in seconds^-1 AKA inverse seconds AKA hertz but 24.25 million hertz and 24.25^6 hertz both seem too low. There seems to be a typo in the formula, they both say v2 or nu2, and they're both cubed I think? Sagittarian Milky Way (talk) 02:11, 16 January 2024 (UTC)

My calculator failed me - it had exp(-27) outside the window. But again, 8.76 exp (-27) What? Watts? Is it even true? Sounds very low to me.Zarnivop (talk) 02:19, 16 January 2024 (UTC)

I fixed an error in index (2->1). So the result for human body is (with $T_{B}=1.380649*10^{-23}$ J⋅K⁻¹, S=1.9 m², $\nu _{1}=10^{9}$ Hz and $\nu _{2}=3*10^{10}$ Hz): P=4.9×10⁻⁶ W. Ruslik_Zero 10:35, 16 January 2024 (UTC)

"Vario speed"??

Siemens claims to have a technology, "Vario speed", that speeds up washing machines cycles without hurting the results. Nowhere did I find what it actually do. Zarnivop (talk) 12:09, 15 January 2024 (UTC)

This technology seems widely used across Siemens products [3]. 78.146.96.26 (talk) 12:30, 15 January 2024 (UTC)

Yes, - or at least they all reduce cycle time and were given the same name. But there is no telling what it is.Zarnivop (talk) 12:49, 15 January 2024 (UTC)

Maybe it's a trade secret. Apparently this company invents 21 things every day [4]. You can check applications at [5]. 78.146.96.26 (talk) 14:03, 15 January 2024 (UTC)

according to 825553 , Reply# 18 it is using higher drum speed (650rpm??) during wash. Zarnivop (talk) 17:49, 15 January 2024 (UTC)

I was hoping they used a bit of intelligence looking at what needed to be done. But no as you say it is running faster - and using more energy. NadVolum (talk) 18:52, 15 January 2024 (UTC)

But for shorter time span. Zarnivop (talk) 01:19, 16 January 2024 (UTC)

More energy overall. NadVolum (talk) 10:17, 16 January 2024 (UTC)

I have seen such a setting on a 'Bosch' (apparently a Bosch/Siemens collaboration) dishwasher. It provided a cycle time approximately 60% of the default 'Eco' cycle time. The dishes came out equally clean, but not so dry. -- Verbarson  ^talk_edits 11:42, 16 January 2024 (UTC)

January 16

Total arable land

Does arable land exclude forests? As land where trees can grow, can also be cultivated by farmers?

https://en.wikipedia.org/wiki/Land_use_statistics_by_country

If USA has so much cultivated land(1,681,826 km sq), then how most Americans are urban citizens?

And Canada has less arable land. Then they have excluded forest area in this list. 2409:40E1:1061:5E7A:99F:C56B:E37A:8102 (talk) 13:12, 16 January 2024 (UTC)

Arable land is land that is plowable and can be used for crops. Trees are not considered a crop in this sense.

There is ebb and flow, but most people in the United States live in urban and suburban areas. They do not live in rural areas. In urban areas, there is high density housing. In suburban, it is dense with apartments and townhomes, but you will also find a lot of subdivisions with single family homes on small lots.

They do exclude forests from arable land. It is not plowed and not available for crops. 12.116.29.106 (talk) 16:52, 16 January 2024 (UTC)

Oxford English Dictionary: Arable...L. arabilis, f. ara-re to plough...Capable of being ploughed, fit for tillage; opposed to pasture- or wood-land. — Preceding unsigned comment added by 78.146.96.26 (talk) 17:06, 16 January 2024 (UTC)

How do you say land that can grow crop(s) in the soil without importing any of soil, water, light, CO2 or fertilizer but not necessarily without first cutting down trees? Would olive trees count as crops? What about olive trees in non-native places like California? What about Christmas tree farms? At some point it becomes so close to forests virgin and left alone except for being lumberjacked every few decades or so that it doesn't seem like crop anymore. Sagittarian Milky Way (talk) 19:15, 16 January 2024 (UTC)

The terminology is used for census and taxes. If the administration in charge of the census and/or taxes wants to consider an olive orchard to be arable, it will be arable. If they don't, it won't. Overall, arable is a subset of agricultural used to designate land prepared for crops. It isn't covered in forest. It isn't all gravel. It isn't under water. It is agricultural land that is ready for crops. My experience is in state census and taxes in Hawaii. There are a lot of rules and waivers for declaring your land to be arable and get a tax discount, which is important because land is very limited in Hawaii, so it is highly taxed, so you want as much of it as possible to be legally arable for a tax discount. 12.116.29.106 (talk) 19:31, 16 January 2024 (UTC)

At what point would a faraday cage stop working?

If you hang a small AM/FM receiver in the middle of a meter-radius sphere and wrap the sphere it wouldn't work anymore, at least if the string's non-conductive and wrap is enough layers of aluminum foil (I don't know if 1 is always enough). If the wave's big enough like 540 AM then if you cut a circular hole in the sphere the hole is much smaller than the wave no matter how big it is but I can't possibly believe a shield with a 180° hole in it would block the signal except possibly if the wave would have to diffract or reflect off the room or something to reach the antenna and probably not even that. So how many degrees wide would the hole have to be before the cage would stop working if the hole was pointed upstream?Sagittarian Milky Way (talk) 18:47, 16 January 2024 (UTC)