May 30

What is the average volume of honey in a bee nest in the wild? I was able to find information on the average volume of a bee nest, but I know that not all of that volume is honey, of course. Thank you! HeyArtemis (talk) 07:49, 30 May 2024 (UTC)[reply]

It varies alot. Honey#Production has a number for Apis mellifera. Sean.hoyland (talk) 08:39, 30 May 2024 (UTC)[reply]

Let's say that an object, such as a star, emits a beam of light and it moves across the space. It goes at the speed of light and, unless it reaches an opaque object, it would keep going... for how much time? Forever? Or is there a point when light would simply dimish and disappear? Cambalachero (talk) 19:53, 30 May 2024 (UTC)[reply]

No.

It may react with matter, if it encounters any. A flux of many photons will spread out to a larger volume and so the intensity (number of photons passing through an area) will diminish in accord with the inverse square law. But light passing through a vacuum does not 'decay' or have a limit on its range.

BTW, this theory that light can only travel a few thousand miles before 'running out' is part of flat earther canon for some models, as an explanation of how nighttime happens. But then they're flat earthers. Andy Dingley (talk) 20:11, 30 May 2024 (UTC)[reply]

The idea of tired light used to be somewhat popular but has been entirely discarded by now. --Wrongfilter (talk) 20:22, 30 May 2024 (UTC)[reply]

I'm afraid it is a zombie idea.^[1]  --Lambiam 05:58, 31 May 2024 (UTC)[reply]

I guess the apparent reality that things in motion continue in motion forever by default, if unperturbed, seems a bit unnatural when you live in a macroscopic world. Sean.hoyland (talk) 07:32, 31 May 2024 (UTC)[reply]

Correct. If that wasn't the case, we wouldn't be able to see stars that are too far away. We are currently seeing stars so far away that they aren't just stars. They are galaxy or similar objects so far away that they show up as one little blob of light. The limit is not how far light can travel before pooping out. It is how old the stars are. For example, a 100 year old star that is 90 light years away would not be visible becuase the original light hasn't reached us yet (ignoring the complication of direction of relative movement). So, the argument is that the night sky should be flooded with light from all directions. And, it is. It only looks black in a relative sense. 12.116.29.106 (talk) 14:51, 4 June 2024 (UTC)[reply]

I imagine it would be much worse than not being able to see stars. If excitations of quantum fields got tired we would be in big trouble. Sean.hoyland (talk) 15:05, 4 June 2024 (UTC)[reply]

May 31

I ask because I came across an article, TXS 1545-234, in the course of regular gnoming. The article claims this radio galaxy to be one of the most distant known objects, but its redshift is only around z = 2.754 (which I take to be measured from radio emissions). It does appear in this source (|date= at least 2006), and I'm wondering whence the claim of such great distance paired with such pedestrian redshift. I'm not able to understand our article Redshift. Also, if anyone has any ideas about how to de-orphan the article linked, please do have at. Folly Mox (talk) 11:31, 31 May 2024 (UTC) edited 11:52, 31 May 2024 (UTC)[reply]

It is certainly not one of the most distant galaxies known. The author of the article, @Galaxybeing:, should explain why they think it is. --Wrongfilter (talk) 12:12, 31 May 2024 (UTC)[reply]

They appear to have made a similar claim at MRC 0406-244 (z = 2.44) although thankfully not at another recent creation, QSO J0100-2708 (z = 3.52). Folly Mox (talk) 12:57, 31 May 2024 (UTC)[reply]

The redshift, a dimensionless quantity, is the same for the whole spectrum emitted by an object. Compared to TXS 1545-234, JADES-GS-z13-0 is thought to be more than three times as far away from us.  --Lambiam 12:37, 31 May 2024 (UTC)[reply]

Thanks both for your answers, and confirming my suspicion that the claim was merely incorrect. Folly Mox (talk) 13:00, 31 May 2024 (UTC)[reply]

A redshift of 2.754 is pretty far away, but stating it's one of the most distant known objects is overstating it a bit. Distances to far-away galaxies are normally expressed in redshift, as redshift is directly observable, in contrast to distance, which depends on a model of the expansion of the universe. But when using redshift as a distance measure, one has to keep in mind that it's highly non-linear. Also, distance is a bit of a strange concept when dealing with these cosmologically distant objects. Are we talking about the distance today, or at the time the light was emitted, or the distance travelled by the light? That last at least has some relevance as it translates to the time that the light has travelled and therefore when it was emitted. JADES-GS-z13-0 may be several times farther away today than TXS 1545-234, but most of that is thanks to the expansion of the universe after the light was emitted. When the universe was young and small (although still infinite), it expanded fast in absolute numbers (percentage per year). In light travel distance, the difference isn't so much.

These objects can be studied to learn more about the early universe. For that, knowing the distance to us is not so important; we want to know about the distance (or time) to the Big Bang. At some point, distances (times) to the Big Bang are known more accurately than distances (times) to us. In any case, the redshift tells us immediately that the universe expanded by a factor of five between the times when the light of JADES-GS-z13-0 was emitted and when the light of TXS 1545-234 was emitted. That puts JADES-GS-z13-0 a lot closer to the Big Bang, although only a small fraction farther from us. PiusImpavidus (talk) 11:05, 1 June 2024 (UTC)[reply]

On a tangent but an amusing use (abuse?) of "red shift": chemists use red shift generically to mean "moves to lower energy". Even in the IR part of the spectrum, the term red shift would be used to describe the shift of a band to lower E, say 2000 to 1950 cm-1. This language is of course strange because, formally speaking, a shift toward red for an IR band would mean a shift to higher E. Just sayin'.--Smokefoot (talk) 17:11, 1 June 2024 (UTC)[reply]

Radioastronomers apply the same "abusive" terminology. We see this linguistic phenomenon also in uses of the verb "to dial", as in the advise to "dial 9-1-1 for any emergency" given to users of smartphones with touch screens. (Using the original rotary sense of the verb in connection with the casual parlance of "butt dial" results in the unfortunate mental image of Giuliani twerking.) Other examples are referring to cotton bed sheets as "linens", or (in the US) to stainless-steel knives, forks and spoons as "silverware", and the computer-graphics terminology calling a screen region a "canvas". I think there is a learned term for this phenomenon if the sense of a word getting abstracted from the physical embodiment after which it was originally named.  --Lambiam 05:29, 2 June 2024 (UTC)[reply]

Astronomers talk about redshift if it goes to longer wavelengths, in radio, IR, UV etc., and about blueshift if it goes to shorter wavelengths, in radio, IR, UV etc. Things can also redshift past red. See how red that distant object in this picture is? It's a feature coming from UV, shifted to IR. The Lyman-alpha absorption line is at 121.6 nm, here broadened into a Gunn–Peterson trough, redshifted to 1.6 μm, between the F150W and F200W filters of the camera in JWST. It's how they make a first estimate of the redshift, based on broadband images. A precise number follows later from spectroscopy, but takes far more observing time, so this is only done for the most promising targets. PiusImpavidus (talk) 10:18, 2 June 2024 (UTC)[reply]

A shop sign is made of a panel that protrudes slightly from the wall on which it is hung, forming an angle of 5° with it. It is 0.74 m tall and has a mass of 8.9 kg. The upper side of the panel is attached to the wall by two cables, one from the right side and one from the left side. Find the tension of the 2 cables 78.211.54.11 (talk) 19:40, 31 May 2024 (UTC)[reply]

Original in Italian, now edited by IP to English.Translates as: "A shop sign consists of a panel that protrudes slightly from the wall on which it hangs, forming an angle of 5° with it. It is 0.74 m high and has a mass of 8.9 kg. The upper end is attached to the wall by two cables, one on the right side and one on the left side. Find the tension in the 2 cables."

IP editor: as it says at the top of this page, we don't answer homework questions and what we do answer should preferably be asked in English. Mike Turnbull (talk) 19:46, 31 May 2024 (UTC)[reply]

Asking homework questions also causes tension. ←Baseball Bugs ^{What's up, Doc?} carrots→ 01:15, 1 June 2024 (UTC)[reply]

Doesn't the tension depend on the angle the cables (idealized as straight line segments) make with the panel?  --Lambiam 02:53, 1 June 2024 (UTC)[reply]

Correct. The answer to the question as asked is a curve of tension vs cable length or vertical location. Greglocock (talk) 22:56, 1 June 2024 (UTC)[reply]

In my interpretation of the problem – which is not necessarily the intended one – the lower edge of the panel is attached to the wall and the panel can rotate along that edge, like in the "or is it like this?" diagram, which has an exaggerated thickness for the panel. Unlike that diagram, the panel does not stick out at a 90° angle but is standing almost upright. Also, the cables are attached to the upper edge. So it is more like the situation here to the right, but instead of a bottom 60° angle we have a 5° angle. Not enough info has been given to determine the other angles.  --Lambiam 04:45, 2 June 2024 (UTC)[reply]
P.S. Another way to frame the problem could have been in terms of a drawbridge.  --Lambiam 04:53, 2 June 2024 (UTC)[reply]

The answer is 42 (glorps). I'll leave it to you to figure out the conversion factor to mks. Clarityfiend (talk) 12:06, 3 June 2024 (UTC) [reply]

                |
      		|'.
		|  '.
		|    '.
		|      '.   
		|        '.
		|          ::
		|         ::
		|< 5deg >::
		|       ::
		|      ::
		|     ::.
		|    :: .
		|   ::  .
		|  ::   .
		| ::    .
		|::     V
		|*      8.9kg

Equate turning moments at *
                      clockwise  =  anticlockwise
 8.9 kg x sin(5 deg) x 0.74m / 2 = t/2 x 0.74m
                         where t = tension in each of 2 cables
                                 = 8.9 sin(5 deg)
                                 = 0.775686... kg

Philvoids (talk) 13:16, 3 June 2024 (UTC)[reply]

Shouldn't there be a sine or cosine factor in the anticlockwise term? Imagine the cables being attached to the wall very close to the *. Consider dU/dL, where U is potential energy of the panel and L is the length of the cables.  --Lambiam 15:27, 3 June 2024 (UTC)[reply]

Although not accurately shown in the ASCII sketch my calculation presumes that the two cables are at right angles to the sign, are parallel and are fastened to the wall separately at two points. This minimises the cable lengths and tensions. Philvoids (talk) 10:28, 4 June 2024 (UTC)[reply]

The homework problem did not specify where the cables are attached or that the tension should be minimized, making it unsolvable for the average student. For an old-fashioned drawbridge over a castle moat, as in the animation, a better choice is to place the attachment point of the cables at a distance from the hinge equal to the length of the bridge, making the triangle isosceles. Otherwise, the tension grows without bounds as the bridge near a vertical position.  --Lambiam 15:37, 4 June 2024 (UTC)[reply]

I could not find an ASCII symbol for a hinge but installing one at the base of the sign is a well thought mechanical improvement that can stop the thing flapping about in a wind. This reference desk cannot grant permission to construct a drawbridge with walkway at this location and the shop owner of the wall would likely protest at your plan to cut a hole for passage. Unless he is a herder of sheep or other small animals and himself less than 74cm tall and sees some advantage. The OP doesn't ask for the cable tension when the sign/bridge is vertical but we can say there are two cases: Case #1: The hinge is broken or absent. t = 8.9/2 = 4.45 kg plus distributed weight of the cable itself; Case #2: The hinge takes the weight, t = 8.9 sin (0) so both cable lengths and tensions are zero. In that case it would be simpler just to nail the sign to the wall. Or put out a call to Banksy who can save us the cost of the sign, usually upset someone and greatly increase the value of the wall. Philvoids (talk) 18:39, 4 June 2024 (UTC)[reply]

For all we know, there is already an opening behind the sign for letting the proprietor's homing pigeons in. If they are equipped with an RFID chip, the sign can be let down automatically on their arrival.  --Lambiam 05:39, 5 June 2024 (UTC)[reply]

Pigeon RFIDs can be compromised by malicious Yinpterochiroptera and Yangochiroptera. Members of this notorious "YinYangBat Gang" equipped with ultrasound-to-UHF converters can mount Spoofing attacks on the shared ID frequency. An ad hoc aposematic remedy such as a wall painting of a cat with the sign text "I EAT BATS" does not alone give security. To this end all pigeons must be urged to register a pass-coo that is less obvious than the too common "Coo Coo". Philvoids (talk) 10:28, 5 June 2024 (UTC)[reply]

June 2

If human embryons of both sexes start off from a female blueprint and given that females lack the male Y chromosome, how it came that women also produce androgens (even if in small quantity), with related limb and facial hair? 212.180.235.46 (talk) 19:59, 2 June 2024 (UTC)[reply]

The article you linked says that the ovaries also produce androgens. ←Baseball Bugs ^{What's up, Doc?} carrots→ 22:33, 2 June 2024 (UTC)[reply]

Biological systems weren't built by any sort of logical designer. They in no way resemble a computer program, a computer, or, for that matter, anything else in the universe. In the case of androgens, the article mentions that androgens are the precursors to estrogens. Males need estrogens too, btw. All these are steroids, which are fundamental to life and are derived from cholesterol. Abductive (reasoning) 23:18, 2 June 2024 (UTC)[reply]

"Biological systems weren't built by any sort of logical designer." Which is why so-called "intelligent design" is just nonsense. The "design" is emphatically not "intelligent". --User:Khajidha (talk) (contributions) 12:07, 3 June 2024 (UTC)[reply]

I'm not sure biology and computing are as far apart as they used to be now that systems essentially create the gigantic opaque function that transforms input to output themselves in response to their environment/what they have seen and the objectives. Generative adversarial networks for example seem a bit closer to biology than systems used to be. Sean.hoyland (talk) 13:06, 3 June 2024 (UTC)[reply]

Not in a billion years. Abductive (reasoning) 17:51, 3 June 2024 (UTC)[reply]

The technology for synthetic biology, still in its infancy, is advancing with large strides. Whether you like it or not, sooner rather than later it will become possible to design and create complete viable and functioning biological organisms.  --Lambiam 06:40, 4 June 2024 (UTC)[reply]

Further, the idea that it is so complicated that nobody understands what it does because it thinks for itself is a farce. No matter what is being used for the computing hardware, be it electronic or biological, the mechanism of operation is very well understood by the engineers who developed it. It just sounds cool to say that it is beyond comprehension. It doesn't sound cool to say that the engineers understand it very well and could trace input through to the output if they wanted to, but simply don't care to do because they have other things to work on. 12.116.29.106 (talk) 14:42, 4 June 2024 (UTC)[reply]

Tracing the input through to the output is IMO not a helpful concept. Not only do we not know why the most advanced chess or go playing programs make certain surprising moves, but it is not even clear what it means to "understand" why they did this. The computing platform performs a calculation with a certain outcome. The engineers can perform the same calculation by hand, or using abaci, and if they make no mistake they may arrive at the same result in a few billion years: 42. But can they say more than that the answer is 42 because this is the consequence of the rules applied to the input? They knew that already. If someone wants to know why it is the consequence, they can tell them to repeat the calculation.  --Lambiam 15:51, 4 June 2024 (UTC)[reply]

IP, LLMs for example involve activations in very high dimensional spaces. Trying to map those activation patterns to things we can understand, like concepts etc., is the whole field of interpretability, and it is in its infancy (and safety critical). Engineers are still far from understanding why input A to a model is transformed into output B. If this is something that interests you, have a look at the work being done in Anthropic's lab. Sean.hoyland (talk) 17:16, 4 June 2024 (UTC)[reply]

Overgrown Markov Chain models are pretty much useless in any technical field. BTDT Greglocock (talk) 04:48, 5 June 2024 (UTC)[reply]

I guess that's one of the reasons why "Attention Is All You Need" turned out to be such a great title for a paper. Sean.hoyland (talk) 08:39, 5 June 2024 (UTC)[reply]

June 5

what are the matrials uesed in implantable artificial prostheses, such as artificial hearts and small-diameter blood vessels; in the engineering of living tissues ? -- 196.153.184.240

Heart valves usually made from pyrolytic carbon. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10034107/#:~:text=Mechanical%20valves%2C%20usually%20made%20from,stroke%20(3%2C%204). 41.23.55.195 (talk) 06:13, 5 June 2024 (UTC)[reply]

Many different materials are used depending on requirements. For details see prosthesis and the many links therefrom.Shantavira|^{feed me} 15:30, 5 June 2024 (UTC)[reply]

June 6

Realistically, how worried should people be about the health risks of consuming taurine as a supplement? I only ask because half the literature says they find it helpful and beneficial at some unknown dosage, while the other half says it is potentially carcinogenic and could contribute to colon cancer. As a layperson, I find this very confusing. Some of the literature says it could be simply a matter of dosage, but nobody seems to know what the safe or harmful limits are. Can anyone offer some risk analysis devoid of emotion? Should we avoid anything with taurine in it, or not worry at all about it? Viriditas (talk) 01:27, 6 June 2024 (UTC)[reply]

As far as Wikipedia is concerned, WP:MEDRS applies. That means that the minimum quality level for WP:RS making medical claims are systematic reviews indexed for MEDLINE (there are some exceptions from this indexation, but generally speaking MEDLINE is the gold standard). tgeorgescu (talk) 03:29, 6 June 2024 (UTC)[reply]

Our article states that there is no good clinical evidence that taurine supplements provide any benefit to human health, Why pay for useless supplements? The human body naturally produces a large amount of taurine, far more than one can reasonably take in as a supplement. There is increasing evidence that taurine actually plays a role in preventing cancer.^[2] Any carcinogenicity of supplements can only be due to their being fake, or a lack of quality control in their production.  --Lambiam 07:23, 6 June 2024 (UTC)[reply]

The underlying issue is that large doses of taurine are added to energy drinks. Nobody seems to know why. A current study is looking at an association between energy drink consumption and the rise in colon cancer in young adults.[3] Viriditas (talk) 08:23, 6 June 2024 (UTC)[reply]

Even disregarding any potential carcinogenic risks, there are enough studies that show damaging health effects of high consumption levels of energy drinks.^[4][5]  --Lambiam 18:28, 6 June 2024 (UTC)[reply]

¼ liter of my favorite energy drink has 80 mg caffeine, while adults usually consume up to 400 mg caffeine per day. And I use the energy drink totally without sugar. tgeorgescu (talk) 18:59, 6 June 2024 (UTC)[reply]

The energy drink thing may be related; most energy drinks contain vitamin B12. There is a concern that (mega)dosing B12 in excess of daily requirements carries with it a slight increase in risk of cancer due to B12 containing cobalt, which is both a heavy metal and has a trace of radioactive cobalt-60. Abductive (reasoning) 20:25, 6 June 2024 (UTC)[reply]

Thank you, that's helpful. I just read the comments by the epidemiologist on that topic, and while my reading might be flawed, they seemed to indicate that dosage and tobacco smoking played a significant role in the risk. Viriditas (talk) 22:02, 6 June 2024 (UTC)[reply]

Real skepticism cuts both ways. Taurine is in human breast milk, evidence of benefit of at least one energy drink exceeding risk. :-) But our article has imho excessive, even dubious doubt in that section on its conditional essentiality or benefit for infants, and thus its common use in another energy drink. Doubt that appears to stem from OR or opinion rather than the source, which says e.g. "Thus the new data provide further support for the view that taurine is a conditionally essential nutrient for the preterm infant" & that ethical considerations seem to prevent further research.John Z (talk) 03:57, 7 June 2024 (UTC)[reply]

June 9

Is this Weigeltisaurus reptile in this family Rhynchocephalia. Would that statement be true to say. Its for this article Johannes Weigelt. There is source that states it but I don't know how accurate it is. scope_creep^Talk 21:23, 9 June 2024 (UTC)[reply]

While Weigeltisaurus flourished in the Late Permian, our article on the order Rhynchocephalia states that the oldest record of the group is dated to the Middle Triassic. According to this chronology, a gap of several million years separates them.  --Lambiam 07:21, 10 June 2024 (UTC)[reply]

Right. I'll leave the Rhynchocephalia bit out and only mention the Weigeltisaurus bit, since I don't understand it. Thanks @Lambiam: scope_creep^Talk 08:52, 10 June 2024 (UTC)[reply]

June 11

June 12

The reaction between a Grignard reagent (${\displaystyle {\ce {RMgX}}}$) and an alkyl halide (${\displaystyle {\ce {R'-X}}}$) gives what product? I see some sources saying there would be substitution reaction thus forming ${\displaystyle {\ce {R-R'+MgX2}}}$, whereas other source says there would be transmetallation thus forming ${\displaystyle {\ce {R'MgX +R-X}}}$. Thanks for your time, ExclusiveEditor _{Notify Me!} 12:19, 12 June 2024 (UTC)[reply]

http://doi.org/10.1007/978-94-017-9861-7_22

Does anyone have access to this? If so, does it make any reference to the diet or hunting behaviour of Euthyrhynchus floridanus? Such claims were added without reference to this insect's article four years ago ([9]), and later someone dumped in a reference to this book. Nyttend (talk) 21:15, 12 June 2024 (UTC)[reply]

I don't think so. The closest I can find is "However, only a few notes about its life history on the field are known (Avila-Núñez et al. 2009 )" The reference is "Avila-Núñez JL, Ortega LDO, Pisarelli MPC (2009) Un caso de depredación de adulto de Gonodonta pyrgo Cramer 1777 (Lepidoptera: Noctuidae) por Euthyrhynchus floridanus(Linnaeus 1767)(Heteroptera: Pentatomidae: Asopinae). Entomotropica 23:173–175". (Btw, you should be eligible for Wikipedia Library; that's how I could access the book).--Wrongfilter (talk) 21:46, 12 June 2024 (UTC)[reply]

June 13