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December 26

Everlasting lightbulb

Is it true that it would be possible to create a lightbulb that never burned out? But that Big Lighting don't do this because it's in their financial interest for people to keep buying replacement bulbs. — Preceding unsigned comment added by 146.200.126.234 (talk) 02:59, 26 December 2022 (UTC)[reply]

Never? It wouldn't be possible to create anything material that would outlive the heat death of the universe. 42.189.193.127 (talk) 03:07, 26 December 2022 (UTC)[reply]

In a case of "they don't make 'em like that anymore", there is the Centennial Light in Livermore, CA. ←Baseball Bugs ^{What's up, Doc?} carrots→ 04:34, 26 December 2022 (UTC)[reply]

We could still have those if brightness inflation didn't happen. At first you could buy extremely low temperature ("warm" color) incandescents that were only a few watts and about as bright as a candle but brightness inflation happened and we get wasteful 100 watt "cool" white incandescents that are about 150 to 130 candles depending on clear or frosted. I unscrewed all but a single clear 15 to 25 watt incandescent in a cheap chandelier and put the dimmer switch way down and could still read and avoid a minefield of Legos at ridiculously low brightnesses (the light was way warmer than without dimming). An incandescent can be easily designed to last over a century if it's dim enough although max duration might need very few turn offs per century (including blackouts and uscrewings). But at least now we have rapidly cheapening 50,000 hour LED bulbs with way more and rapidly increasing light per watt than incandescents. Which is already leading to 300 watt equivalent LEDs as soon as efficiency raises the "brightest LED we can make that lasts a sane time" to that. People are never satisf

ied. Sagittarian Milky Way (talk) 18:03, 26 December 2022 (UTC)[reply]

"might need very few turn offs per century " : maybe this is the most important point. Turning on/off and cooling down/heating up places a strain on it much higher than simply emitting light. Bumptump (talk) 11:56, 29 December 2022 (UTC)[reply]

That bulb's fate is told in "17776" iirc. —Tamfang (talk) 18:46, 30 December 2022 (UTC)[reply]

I'm not sure about never, but you used to be able to buy "long-life" filament bulbs that simply had a thicker filament so they were not very bright. But there is some truth in the idea of their planned obsolescence. See Phoebus cartel. Shantavira|^{feed me} 09:20, 26 December 2022 (UTC)[reply]

some good advice here: [1] Dr Dima (talk) 00:25, 28 December 2022 (UTC)[reply]

December 27

Late Cretaceous American Interchange: Where is the Smoking Gun?

OP has been indef'd

The following discussion has been closed. Please do not modify it.

How is there any proof that there was an actual american biotic interchange between South American fauna and North American fauna during the late Cretaceous? keep in mind that the american biotic interchange that started during the Piacenzian had terror birds, glyptodonts, megalonychid ground sloths, megatheriid ground sloths, nothrotheriid ground sloths, toxodontids, new world porcupines cross over from South America into North America while gomphotheres, dire wolves, sabertooth cats, spectacled bears, jaguars, cougars, camelids, white-tailed deer, marsh deer crossed over from North America into South America, so if there was an actual american biotic interchange during the late Cretaceous, why is there no evidence of animals like abelisaurs, megaraptorans, noasaurids, elasmarians, notosuchians, unenlagiinae unenlagiids crossing over from South America into North America and animals like lambeosaurine hadrosaurs, edmontosaurini hadrosaurs, chasmosaurine ceratopsids, centrosaurine ceratopsids, tyrannosaurids, eudromaeosaurs crossing over from North America into South America? CuddleKing1993 (talk) 09:09, 27 December 2022 (UTC)[reply]

The animals that you list as crossing between North and South America all lived many millions of years after the end of the Cretaceous. CodeTalker (talk) 03:52, 28 December 2022 (UTC)[reply]

The OP wrote that these animals crossed during the Piacenzian (in the Great American Biotic Interchange, using the Panamanian land bridge that formed during that age). The question – as I interpret it – is, why didn't a similar exchange take place during the late Cretaceous? The tragic fact of the matter is, as was pointed out to the OP before, in the late Cretaceous, North America was not connected to South America. --Lambiam 07:57, 28 December 2022 (UTC)[reply]

So why did apparently kritosaurini hadrosaurs and nodosaurs cross over into South America? CuddleKing1993 (talk) 11:16, 28 December 2022 (UTC)[reply]

To repeat myself from 11 days ago in response to an earlier question "according to this paper there was probably a link between North and South America during the Campanian (Late?), via a line of volcanic islands, allowing "a dispersal route for hadrosaurids and other vertebrates"." Mikenorton (talk) 14:18, 28 December 2022 (UTC)[reply]

Then why did only kritosaurini hadrosaurs and nodosaurs disperse into South America? CuddleKing1993 (talk) 20:30, 28 December 2022 (UTC)[reply]

Maybe some of them couldn't swim? Maybe all of them could swim, but the inter-island seas were hazardous and only the two you mention were lucky enough to make it all the way? Maybe some that made it part of the way were then wiped out by volcanic eruptions? If you haven't found the answer in peer-reviewed literature, then almost certainly no-one knows. Maybe future discoveries will allow someone to figure it out, in a century or two from now. Maybe we'll never know: Paleontology is like that. {The poster formerly known as 87.81.230.195} 51.194.245.235 (talk) 12:34, 29 December 2022 (UTC)[reply]

December 28

IQ and Sex

Are there any scientific studies on the difference in intelligence between the sexes? In particular, I am interested in whether it is true that boys are slower to mature intellectually. Are there studies? 2A02:908:424:9D60:0:0:0:8846 (talk) 23:10, 28 December 2022 (UTC)[reply]

This very much depends on one's definition of intelligence. Shantavira|^{feed me} 09:14, 29 December 2022 (UTC)[reply]

There are, cat , pigeons. https://www.nature.com/articles/nature04966 Greglocock (talk) 01:25, 29 December 2022 (UTC)[reply]

Sex differences in intelligence would be a good place to start. Clarityfiend (talk) 06:14, 29 December 2022 (UTC)[reply]

It seems very strange for Nature to have a paper about sex differences in IQ when IQs are set up balancing up any differences so overall there is no difference. Intelligenceis a better name for what you're looking for but it is multi faceted. NadVolum (talk) 19:30, 29 December 2022 (UTC)[reply]

IQ tests are calibrated for a given population so that the distribution of test scores closely approximates a normal distribution whose mean equals 100 and whose standard deviation equals 15. Therefore it is meaningless to compare scores for population A obtained with a test for population A with scores for population B obtained with a test for population B. If there is a significant difference between the distributions, it signals a problem with the calibration. However, this does not mean that the distributions for two subpopulations of a given population are the same. If you compare the IQ scores of 25-year old college dropouts with those of 25-year olds who earned a PhD, it will be amazing if you don't find a difference. There is no a priori reason why there would not be sex-related differences in the distributions of height, or muscular strength, or hearing acuity, or pain endurance, or empathic ability, or remembering people's birthdays, or whatever. People should (IMO) get over with being so absurdly focused on IQ as if scoring 130 makes one more valuable then another human being who scores 70. The high scorer may be a total douchebag, while the other is a caring spouse and parent, bringing happiness to the lives of many. Also, inasmuch as intelligence has relevance for our daily life, it is really multifaceted, in a way a single score cannot capture. --Lambiam 20:02, 29 December 2022 (UTC)[reply]

Book smarts vs. street smarts. ←Baseball Bugs ^{What's up, Doc?} carrots→ 22:39, 29 December 2022 (UTC)[reply]

Crack Theory: Kritosaurini were NOT hadrosaurs?

OP has been indef'd

The following discussion has been closed. Please do not modify it.

What if Kritosaurini were actually lineage of iguanodonts that resembled true hadrosaurs through convergent evolution with a ghost lineage from the late Jurassic or early Cretaceous that were widespread across the globe? CuddleKing1993 (talk) 23:51, 28 December 2022 (UTC)[reply]

What if dolphins were actually ichthyosaurs? Do you have an actual question? --OuroborosCobra (talk) 01:31, 29 December 2022 (UTC)[reply]

My question was trying to understand why kritosaurini iguanodonts were found in South America. CuddleKing1993 (talk) 01:58, 29 December 2022 (UTC)[reply]

@CuddleKing1993:, just a note; talk pages are not a general forum. --Magnatyrannus (talk | contribs) 02:46, 29 December 2022 (UTC)[reply]

December 29

What will the Andromeda–Milky Way collision look like?

Assuming the Andromeda–Milky Way collision is really going to happen, if there would be anyone on Earth left to see it, what would it look like? Would it look like a great lot of stars getting brighter and brighter, then getting dimmer and dimmer again? JIP | Talk 19:56, 29 December 2022 (UTC)[reply]

Stars will remain the roughly same but their configuration will change, with the Milky Way band gradually disappearing. Ruslik_Zero 20:08, 29 December 2022 (UTC)[reply]

The Hubble Space Telescope captured this image of two colliding galaxies. Located 300 million light-years away in the constellation Coma Berenices, the view has been nicknamed “The Mice” because of the long tails of stars and gas emanating from each galaxy. Otherwise known as NGC 4676, the pair will eventually merge into a single giant galaxy. Philvoids (talk) 20:31, 29 December 2022 (UTC)[reply]

That picture is taken from the viewpoint of an outside observer. What I was asking about is, assuming humanity still existed on Earth when the collision comes to pass, what would it look like to an observer standing on the Earth and looking at the Andromeda galaxy approaching the Earth. I presume the galaxy would eventually start appearing to the naked eye as it does on the space telescope photographs. What would it look like when it comes even closer? Would the sky be engulfed in the interstellar gas which shows up so prominently in the space telescope photographs, or is it too sparse to be visible when viewed right up close? JIP | Talk 23:50, 29 December 2022 (UTC)[reply]

From within, it would depend on whether the observer is in a starburst region. Inside that area there would be a lot of bright, new stars with short lives. Outside those areas where stars are created quickly, it would look about the same as always, just rearranged. After the starburst is over and things have settled down, the star population would be increasingly older stars with little interstellar matter. See starburst galaxy for more -Messier 82 is the closest example, and Messier 81 has brightened up too. But the view from inside would depend on whether you're in a star-creating region. That area, though, might be a little hazardous, with a higher frequency of supernovas and gamma ray bursts.Acroterion (talk) 23:59, 29 December 2022 (UTC)[reply]

Thank you, this gives me more information about the scenario. JIP | Talk 00:04, 30 December 2022 (UTC)[reply]

"Short" and "quick" on astronomical time scales, but not on a human time scale. To the unaided observer, the night sky would not change perceptibly from year to year. The occasional (super)nova would be an exception, but these would still be relatively rare events. --Lambiam 10:24, 30 December 2022 (UTC)[reply]

The Andromeda galaxy (or at least the central, brightest part) is already visible to the naked eye, assuming you're in a properly dark place (hard to find these days in Europe, but in Finland you should be OK) and have good eyesight. As it gets closer, it gets brighter and larger, but the surface brightness doesn't change. The Andromeda galaxy will remain a dim feature in the sky. At some point, tidal forces will warp and disrupt the disks of the galaxies, so that bright band of the Milky Way will get diluted and disappear. We can only see it now because we have a very long line of sight within the disk. At the same time, gas gets stirred up, leading to a burst in star formation and supernova rate, leading to a lot of clusters of bright stars, visible by naked eye from all over the merging galaxy pair. That could be quite spectacular, if the changes weren't so slow that you could never notice it on human timescales. PiusImpavidus (talk) 10:19, 30 December 2022 (UTC)[reply]

I have seen M31 from the outskirts of a medium-sized city. —Tamfang (talk) 18:48, 30 December 2022 (UTC)[reply]

Now, M33 is more of a challenge. I've seen it with the naked (well, bespectacled) eye in the UK a few times, but in recent decades only from decently dark sites, one of which had an astronomical observatory built on it. {The poster formerly known as 87.81.230.195} 51.194.245.235 (talk) 19:58, 30 December 2022 (UTC)[reply]

Now here's a challenge. Apparently all seven planets are visible after sunset - that's Mercury, Venus, Mars, Jupiter, Saturn, Uranus and Neptune (the last two by telescope only) though not in that order. This state of affairs will not last, because Mercury will fade in the next few days. 89.243.13.100 (talk) 21:40, 30 December 2022 (UTC)[reply]

Human extraterrestrial life?

Here's a question for you: could humans adapt to life on Mars, Europa, Enceladus, or Titan? 67.215.28.226 (talk) 20:48, 29 December 2022 (UTC)[reply]

Have humans adapted to life in the far north, does an Inuit with a nice fur coat count as adaptedas far as you are concerned? NadVolum (talk) 22:13, 29 December 2022 (UTC)@[reply]

No. I am asking without a spacesuit? 67.215.28.226 (talk) 22:18, 29 December 2022 (UTC)[reply]

Only if a massive terraforming project was undertaken. ←Baseball Bugs ^{What's up, Doc?} carrots→ 22:36, 29 December 2022 (UTC)[reply]

Okay, thank you. ;) 67.215.28.226 (talk) 22:54, 29 December 2022 (UTC)[reply]

Essentially the same question was asked earlier this month: Could humans somehow adapt to new planets / satellites (like Titan)? --Lambiam 10:16, 30 December 2022 (UTC)[reply]

And still we are unable to answer questions here which call for speculation, not to mention the biomedical information involved. Elizium23 (talk) 02:41, 31 December 2022 (UTC)[reply]

There's no problem with discussing biology or medicine. Medical diagnosis and advice are what we avoid. Card Zero (talk) 03:51, 31 December 2022 (UTC)[reply]

Recent human evolution discusses some of the ways in which humans continue to adapt to their environments. If placed in an extra-terrestrial environment for many generations – in some kind of artificial habitat – humans could be expected to adapt further. Dramatic evolutionary change happens slowly, for complex organisms like humans that reproduce slowly. An adaptation such as improved tolerance for the planet's gravity, or for the Martian_soil#Dust_hazard, would take fewer millenia than a major change such as being able to breathe the atmosphere: 20 million years of hominid evolution hasn't been enough time for anything so dramatic to happen on earth, for instance there are no humans living under the sea (without the aid of equipment). Card Zero (talk) 05:46, 31 December 2022 (UTC)[reply]

December 30

"A tiger! In Mexico?"

I recently watched The Treasure of the Sierra Madre and one of the things that seemed odd to me was repeated references to tigers, despite the film being set in, well, the Sierra Madre of Mexico. Multiple characters bring it up in multiple contexts. They bring up lions as well, which I assume refers to cougar, but what do they mean by tiger? Were jaguars ever referred to that way? I can't think of anything else that's even close. Despite being filmed on location, the film-makers also decided to add Kookaburra calls liberally to the background noise, so it's not like they were making a documentary, but I thought I'd ask if there was anything other then carelessness involved. Matt Deres (talk) 01:58, 30 December 2022 (UTC)[reply]

It seems that in Mexican Spanish, the jaguar was referred to as 'el tigre'. [2] B. Traven, who wrote the novel the film was based on, seems to have spent much of his life in Mexico and presumably used the local term. AndyTheGrump (talk) 02:16, 30 December 2022 (UTC)[reply]

Great - thank you! Now, about the kookaburra... Matt Deres (talk) 02:53, 30 December 2022 (UTC)[reply]

Kookaburra#Film covers that in some detail. I heard one in my front hard this morning, but I AM in Australia. HiLo48 (talk) 02:59, 30 December 2022 (UTC)[reply]

If you heard a kookaburra coming from your "front hard", I suspect you need to a see a doctor. Or a talent agent. Matt Deres (talk) 23:09, 30 December 2022 (UTC) [reply]

Whoops. Yard. HiLo48 (talk) 01:04, 31 December 2022 (UTC)[reply]

I suspect the kookaburra was just used to add ambience, perhaps a little tongue-in-cheekily, just like film music (and of course the loon). Jungle scenes are notorious for including anatopic sound effects. Shantavira|^{feed me} 09:31, 30 December 2022 (UTC)[reply]

I was well into adulthood before I was persuaded that tigers do not occur natively in Africa. Till then, I believed what I saw on a stack of Jungle Jim and Bomba, the Jungle Boy movies. Hollywood would never lie, not to little kids, surely. -- Jack of Oz ^{[pleasantries]} 10:20, 30 December 2022 (UTC)[reply]

Like when Chilly Willy, the penguin, would interact with polar bears. ←Baseball Bugs ^{What's up, Doc?} carrots→ 12:15, 30 December 2022 (UTC)[reply]

Exactly. -- Jack of Oz ^{[pleasantries]} 17:33, 30 December 2022 (UTC)[reply]

Do we know which human being, specifically, designed the HDMI port?

I know (from the HDMI article) that the HDMI standard was propagated by a group of seven companies, but has any individual person ever been credited with the physical design of the HDMI port and plug themselves?

Not that I want them to answer for their crimes or anything, but... --24.76.103.169 (talk) 17:08, 30 December 2022 (UTC)[reply]

I'd guess t was a team effort, but I don't see what you have particularly against it. The USB2 plug now, that does deserve a bit of ire. It always seemed to take three goes to get it to fit, try one way up and it doesn't fit, try it the other way and it still doesn't fit, then try the first way up again and finally it seemed to fit. :-) NadVolum (talk) 00:04, 31 December 2022 (UTC)[reply]

They're far too fragile for what they're being used for these days. The most common game console repair is an HDMI port replacement, because with even careful use they can easily be damaged. --24.76.103.169 (talk) 01:27, 31 December 2022 (UTC)[reply]

Date of the Cretaceous–Paleogene boundary

Back in the 1990s, I always used to hear people refer to the end of the Cretaceous period as "65 million years ago", but in recent years, an estimate of 66 million years seems to have become ubiquitous. I'm mildly curious about why and when the estimates were changed. A glance at the article history for Cretaceous shows that "65 million" was the date given when the article was created in 2001, that 65.5 was the estimate in the mid- to late 2000s, and that 66 was in place by the end of 2009. So I assume the shift in the scientific literature took place over the course of the 2000s, with Wikipedia probably lagging somewhat behind, but does anyone know why the dates were revised? A. Parrot (talk) 19:55, 30 December 2022 (UTC)[reply]

Consensus has grown that the boundary is defined by the Chicxulub impact whose direct and indirect after-effects largely if not entirely caused the changes which lead to our distinguishing the two Periods. Continued scientific investigations over recent decades have gradually refined the precision of our dating of that event, currently to 66.043 ± 0.043 million years ago. {The poster formerly known as 87.81.230.195} 51.194.245.235 (talk) 20:08, 30 December 2022 (UTC)[reply]

Is there an article about this topic?

It's about imagining fake scenarios as a form of escapism. Neocorelight (Talk) 20:44, 30 December 2022 (UTC)[reply]

I've not read the report, but it has been pointed out that when you close your eyes when it's dark you do not see black nothingness but images, because your brain will not allow anything else. 89.243.13.100 (talk) 21:25, 30 December 2022 (UTC)[reply]

That's not at all my experience. No images unless I specifically want to imagine one. There's quite a lot of difference between people. NadVolum (talk) 00:19, 31 December 2022 (UTC)[reply]

I can't read the report but is this to do with hypnagogia? Shantavira|^{feed me} 09:29, 31 December 2022 (UTC)[reply]

Lop-sided earth?

Today, I've learned that 70% of land on Earth is in the Northern Hemisphere. Why is our planet so lop-sided in terms of land in different hemispheres? 67.215.28.226 (talk) 21:59, 30 December 2022 (UTC)[reply]

This looks interesting:

. 89.243.13.100 (talk) 22:31, 30 December 2022 (UTC)[reply]

I suspect, but don't know, that the important to us - land - is just a dusting of foam on the tectonic plates. Greglocock (talk) 07:14, 31 December 2022 (UTC)[reply]

Hello, Greglocock. Major movements of Plate tectonics take place over billions of years. The magnetic poles move around and even reverse on much shorter time scales. The true poles of rotation are known to "wobble" a few meters on very short time scales. I do not know what the wobbling is over a billion years. The broader question is whether or not plate tectonics is influenced by the location of the equator. Is there a mechanism that gradually influences continental plates to drift northward, or is this a case where a random roll of a dice tumbling for a billion years comes up with five plates slowly migrating north from our current point of view, instead of three or four? All are equally likely. Now, the people who are much smarter than me can comment. Cullen328 (talk) 07:59, 31 December 2022 (UTC)[reply]

Like most things in nature, it's just down to chance. There is no reason for the land masses to be distributed perfectly evenly either. Shantavira|^{feed me} 09:36, 31 December 2022 (UTC)[reply]

Yep. If you look at Pangaea#Formation of Laurasia, the distribution of dry land was once even more biased toward the southern hemisphere. Someguy1221 (talk) 09:47, 31 December 2022 (UTC)[reply]

December 31