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July 29

Epigenetic reprogramming

Is it possible to perform epigenetic reprogramming on cells as a private person? 2A02:8071:60A0:92E0:9B9B:C02B:F5CC:22D1 (talk) 11:52, 29 July 2023 (UTC)[reply]

Epigenetics? How much money ya got? ←Baseball Bugs ^{What's up, Doc?} carrots→ 13:23, 29 July 2023 (UTC)[reply]

Not in any way that could be targeted or healthy. Epigenetic changes are typically induced by stress. Abductive (reasoning) 15:31, 29 July 2023 (UTC)[reply]

Eh, I think that's a little misleading as a generalization. Epigenetic effects are a part of the normal, everyday functioning of one's cellular and systems physiology level of functioning, occurring constantly, and not always as a result of catalysts that one would normally classify as 'stress' (in either the clinical or idiomatic senses). Every new memory or perspective you form (to take just the most obvious example from one organ) is the result of epigenetic effects. SnowRise ^{let's rap} 18:35, 29 July 2023 (UTC)[reply]

What does money have to do with it? I think you might be confusing gene editing with gene expression. SnowRise ^{let's rap} 18:35, 29 July 2023 (UTC)[reply]

OP, I'm not entirely certain about what you mean by "reprogramming". Epigenetics is a term which roughly defines the subject of how the various genes collectively comprising an individual's genome are expressed; specifically the interplay between environmental/extrinsic factors, the organism's coded genetics, and the various biochemical mechanisms which mediate the influences of the former upon the latter, triggering triggering RNA and protein activity causing cellular (and ultimately broader physiological) effects, causing certain traits to turn on or off or change the mode of their expression. That's a really simplified version of a very complex set of biophysical pathways, but suffices to grapple with your question. To wit:

If by "reprogramming" you mean causing changes in the expression within a cell, then yes, not only is that possible, it inevitably happening every second of your life.

If you mean using gene therapy or other genetic engineering (altering DNA is some other artificial/biomedical fashion), then that is a very complex question and the answer depends on whether you are asking if it is practically feasible to do so as an individual or if it is regulatorily permitted, each of which would require paragraphs here to just summarize the answer (but the gist of which would be "generally speaking: no, not really", in both cases). Let me know if one of those was the sense in which you intended your question and I can elaborate further, with some additional wikilinks and sources. However, crucially, this would not be accurately described as "epigenetic reprogramming" but just "genetic manipulation", since it would be the underlying genes altered (though this would of course have knock on effects for the epigenetic functions that rely on that underlying genetic code).

Finally, if you mean using epigenetic expression to create a kind of feedback loop which actually impacts DNA and genetics, that is technically a thing that happens, since DNA does to some extent get altered during the normal physiological functioning of an organism as complex as a human over a lifetime, and you can, in a sense, say that any expression of a gene/resulting expression of trait/physiological activity is going to have consequences in this regard. But this is really unpredictable and cannot really be leveraged for specific, tailored results--and if one were at the stage of scientific development where the could manipulate DNA in this way, their knowledge of genetics and biochemistry would be so advanced and detailed, they would essentially already be capable of tailoring their genetics and resulting gene expression with very few intrinsic limitations through more direct means, as an almost per se matter. SnowRise ^{let's rap} 18:35, 29 July 2023 (UTC)[reply]

I suspect the OP is referring to something like Epigenome editing. I say like, since I'm not sure the OP really understands the Epigenome. I don't know if this applies to the OP but IMO there's a tendency to think of it as a simple additional largely universal to the individual code like the genome, perhaps only being aware of one or two parts of what can be called the epigenome perhaps specifically DNA methylation with being aware of the complexity. Nil Einne (talk) 07:56, 30 July 2023 (UTC)[reply]

You may very well be right as to what the OP was roughly inquiring about. But there's no doubt that you're right as to the more general point. Epigenetics does include many discrete (and sometimes quite well quantified and qualified) biophysical mechansism and pathways, but ultimately it's a topic best understood through the lens of systems biology if ever there was one. However, for those coming to the topic new and/or with a superficial understanding of those discrete parts, many will just intuit epigenetics as being mostly about changes to the epigenome itself, and specifically with regard to intergenerationally persistent phenomena. But changes to heritable traits are a truly tiny fraction of the implications of how epigenes and epigenetic mechanics operate. Hopefully what I'm saying makes sense to any readers here: this is one of those topics where I sometimes feel like I may be spewing inscrutable word salad to those who don't already understand the point I am trying to make. SnowRise ^{let's rap} 02:16, 31 July 2023 (UTC)[reply]

July 30

2023 nematode revival

Hi! Should there be an article about the nematode revival? It seems like it's article-worthy! 2402:9D80:272:BD02:694E:B788:6748:A701 (talk) 10:09, 30 July 2023 (UTC)[reply]

It is mentioned in our nematode article. If you think there is enough material for a standalone article you are welcome to create one. See Wikipedia:Articles for creation. Shantavira|^{feed me} 12:00, 30 July 2023 (UTC)[reply]

The fact that nematodes can survive long periods of deep frost is old news. The previous record was 42,000 years,^[1] so the new record of 46,000 years is not astounding. The feat is perhaps more the ability of the researchers to find and identify permafrost of that age. --Lambiam 12:04, 30 July 2023 (UTC)[reply]

Cooking bacon in microwave

Anyone know if any of those devices you see for sale that claim to allow you to microwave bacon without mess actually work? Or does the inside of the microwave invariably end up getting laminated with bacon fat anyway? My cooker is broken and as wonderful as my Foreman is, I've never liked the way bacon turns out in it (too dry), so am considering trying microwave. Iloveparrots (talk) 15:16, 30 July 2023 (UTC)[reply]

Alansplodge (talk) 16:13, 30 July 2023 (UTC)[reply]

Thanks. Some of those look as though they'd struggle to cook back bacon properly, or even fit it in there. Iloveparrots (talk) 16:36, 30 July 2023 (UTC)[reply]

At the very least, you'll want to "contain" it some way, within the microwave, for cooking anything that can tend to splatter. You should be able to find something that looks like an inverted frying page (without a frypan handle), usually made of clear plastic or some other see-though material, to totally cover it except for a few vent holes. ←Baseball Bugs ^{What's up, Doc?} carrots→ 18:59, 30 July 2023 (UTC)[reply]

A few of the problems with cooking bacon in the microwave are that microwaves have trouble with two things that make cooked bacon taste good. Those are heat and time. That's because things like the Maillard reactions require certain temperatures, AND require more time at those temperatures, than a typical microwave can impart. So called microwave "bacon cookers" mostly attempt to fix this by providing some kind of conductive surface so heat spends more time in contact with the bacon. As Alanspoldge notes above, if you google "microwave bacon cooker reviews" or something like that you'll find reviews of various devices, YMMV, caveat emptor, etc. etc. --Jayron 32 12:35, 31 July 2023 (UTC)[reply]
If you have a working oven, cooking bacon in an oven is an excellent, or even superior, method to frying it in a pan on the cooktop. There are many recipes available on the Internet but they're all basically the same: cook in a baking sheet at 400 F for 10-20 minutes, depending on how crispy you want it. CodeTalker (talk) 15:45, 31 July 2023 (UTC)[reply]
Also useful to help cook in a pan is a "bacon press". Basically a big piece of cast iron with a handle on it. The weight keeps the bacon in contact with the cooking surface and helps it cook quicker and more consistently. --Jayron 32 16:56, 1 August 2023 (UTC)[reply]
Clearly nobody responding above considered registering under the user name 'Ilovepiggies'! SnowRise ^{let's rap} 23:49, 31 July 2023 (UTC)[reply]

July 31

I think I have a complex

Complexity theory, complex systems theory, systems theory, dynamical systems theory. Perhaps I'm forgetting some. How do these map? Are any of these not a real field? What is subsidiary to what? Temerarius (talk) 01:49, 31 July 2023 (UTC)[reply]

Systems theory appears to be an overarching topic, so spend some time reading our article, which links in those other topics. Graeme Bartlett (talk) 02:42, 31 July 2023 (UTC)[reply]

H'oh-boy, you're really asking a whopper here: these are all deeply complex (ironic phrasing incidental but unavoidable) and at least semi-interdisciplinary concepts with nebulously defined borders, varied applications and sometimes difficult to articulate implications. But I'll give it a try. I was just about to be out the door, so I may need to stage this response. Here goes though.

I'll start with systems theory because it is the paradigm I am most familiar with and I believe can fairly said to be the broadest topic of the lot. Though saying that, I also note that none of the terms you employed refers to a field of thought that is necessarily a formal subdomain of that of one of the other terms, if that makes sense. They all just use similar terminology for semi-convergent purposes.

That caveat done, systems theory is all about understanding phenomena on the basis of their interaction with larger collectives of phenomena. It can be considered (and this is not necessarily the formal definition, but one which I think is helpful at understanding it's boundaries at first blush) as an effort to nest all naturalistic processes and mechanisms within countlessly recursive layers of scale and complexity). In the broad strokes, it is a highly ambitious and holistic method for trying to relate all phenomena. But also, on a less macro-level, it is a way of thinking about even discrete systems, interactions, and pathways as being better understood by their borders and feedback with other phenomenalistic systems. In other words (and I know this is getting highly abstract, ontologicaly dense, and maybe even a little unwieldy sounding, but a thing is best understood by what it does and what is done to it, not just a description of it's parts.

With regard to theories of complexity (to reorder 'complexity theory' into something more workable and consistent with how those terms are often related, for our purposes here), I don't think there's one standard definition of the way the nomenclature is used across the fields in which the concept (of understanding phenomena by virtue of their complexity) arises, but there are some commonalities: complexity models mostly concern how many subparts of a given system there are, how dynamic (that is, generally how reliably defined they are) each component is in its own right, and the computational implications for predicting the behaviour of the holistic systems. That said, on this topic it is too bad SemanticMantis seems to be on hiatus, because I am certain they could give you a more accessible and robust definition. "Complex systems theory" is somewhat more a neologism than either of the other above terms, but I interpret the phrase as meaning just as what you might assume from combining the above two foci of the individual terms: it is about understanding systems comprised of larger numbers of and/or highly dynamic systems.

Which brings us to dynamical systems theory, where I am most out of my depth. This is a good place to note that all of these models have both more analytical and computational components, and more theoretical/broad framework applications, but some lean more to one than the other. You're going to get more broad philosophical generalizations from (at least some) big systems theory thinkers, but dynamical systems theory is almost incidentally using a similar label. It's a purely mathematical approach to crunching data relating to complicated systems by way of functions related by complex equations. And if that is a bit of an earful, I apologize, but I barely possess the vocabulary to conceptualize the broad strokes of these mathematics, let alone find novel ways to express them. Suffice it to say, I would categorize this field as much more discrete than the others, and much more bounded by strict analytical rules, expressly defined inputs, and straight-forward (if highly complex, obviously!) transformative operations.

Was any bit of that helpful?? I hope so, but I'm not sure it will be! SnowRise ^{let's rap} 03:01, 31 July 2023 (UTC)[reply]

Yes, that was a wonderful response! I'll need a minute to digest it, and I hope the robustness of your reply doesn't prevent others from pitching in. Thank you! Temerarius (talk) 03:33, 31 July 2023 (UTC)[reply]

Very happy to help Temerarius! And happier still that what I wrote was basically decipherable. :) I found myself thinking about examples earlier that might further clarify the distinctions here and better emphasize the the applications/raison d'etre of a couple of these fields, and came up with a couple of good ones, but I'm running around putting out fires at the moment, so you'll have to be patient with me in getting them down in paragraphs here.

In the meantime, it also occurred to me that I should mention that there is a movie called Mindwalk that you might be interested in: it's a fairly accessible (indeed, if anything, oversimplified maybe) primer to systems theory based on the writings of Fritjof Capra, one of the academics/public intellectuals who helped popularize systems theory. It's pretty slow: it's just a dialogue between three people (a scientist, a poet, and a politician), discussing the philosophical underpinnings of what was at the time a somewhat novel way of relating naturalistic phenomena, physical and otherwise; it borrows this structure from Galileo's Dialogue Concerning the Two Chief World Systems. It won't set your world on fire with new ideas, I don't think, but you can definitely get a sense of (at least Capra's idea of) how systems theory tries to address describing the physical universe. Plus it must be said that Sam Waterston plays "Simplicio" to perfection therein. ;).

If I recall correctly, Mindwalk is mostly based on Capra's The Turning Point, which is also highly accessible for a book in this area--but also a little preachy and proselytizing as I recall it: Capra also wrote the much better known The Tao of Physics, so if you're familiar with that book you'll have an idea of what I mean. It's constructed on top of hard science, but also contains lot about social philosophy, ideology, and policy. I read all of Capra's work (at the time) a couple of decades back and I think my overall impression was that he was somewhere between brilliant and very heavy-handed as a writer and psuedo-policy thinker. But you can definitely do worse for an entry point on systems theory. SnowRise ^{let's rap} 23:43, 31 July 2023 (UTC)[reply]

My attempt, as I understand these terms. Complexity theory is an ambiguous term, but one meaning is complex systems theory, that is, the field of study of complex systems. In this context the term system usually refers to a dynamical system, a collection of components that evolve in time while interacting with each other – the behaviour of one component can have an effect on other components. For example, the system could be a deliberating jury, and the components are the jurors. For a mathematical treatment, when modelling a system, the relevant aspects are modelled as numeric values – perhaps the strength of a juror's conviction that the alleged facts have been proved beyond a reasonable doubt. Some dynamical systems are very simple, which is generally the case for systems with fewer than three components; such systems are never chaotic. A system is called chaotic when its collective behaviour is chaotic, which means that it is impossible to predict the long-term future evolution on the basis of past observations. Weather is a prime example; no one can reliably predict whether it will rain in Amsterdam on the first of August of next year. Chaos theory is about understanding when systems become chaotic, as well as determining what can be said about the evolution in spite of the chaos. Chaotic systems can be reasonably simple (just three components), while some very complex systems are nevertheless not chaotic. --Lambiam 08:19, 31 July 2023 (UTC)[reply]

There once lived a man named Oedipus Rex / You may have heard about his odd complex --47.155.41.201 (talk) 18:39, 3 August 2023 (UTC)[reply]

August 1

Alias for inflationary blood pressure measurement

I am studying inflationary blood pressure measurement devices. Because it is rather new, I assume the name of the type of device hasn't settled on a specific term. The devices I've found are all made by one company, Welch-Allyn. I've been trying to find an alias for the device name so I can find similar devices from other companies. By chance, does anyone here recognize this class of devices and know other models? 12.116.29.106 (talk) 11:35, 1 August 2023 (UTC)[reply]

Do you mean a sphygmomanometer? -- Verbarson ^talk_edits 11:37, 1 August 2023 (UTC)[reply]

Or maybe this gizmo [2]? Alansplodge (talk) 12:13, 1 August 2023 (UTC)[reply]

Yes. That is it. It says it uses linear inflation technology where the devices I was already looking at use the term inflationary. But, at least that is another company making the same type of device. With two companies, I have a better chance of finding competitors. 12.116.29.106 (talk) 13:33, 1 August 2023 (UTC)[reply]

In the UK, the company that makes almost every blood pressure monitor I've seen is Omron.--Phil Holmes (talk) 14:01, 1 August 2023 (UTC)[reply]

How does hobby glue work?

I want to use a certain brand of adhesive for a task. It is sold as a general purpose hobby glue supposedly able to stick just about anything. The packaging says it is a mix of acetone 45% (average), ethyl acetate 20% (average), and n-butyl acetate 5% (average). This adds up to only 70% - the packaging does not say what the missing 30% is. The distributor provides a Material Safety Data Sheet - it just says the balance is determined to be non-hazardous and doesn't say what the balance is.

Question: Given the listed ingredients are all solvent liquids, what is the balance likely to be?

This adhesive upon exposure to air changes from a low viscosity clear colourless liquid to a soft rubbery translucent material within a few minutes, then gradually goes quite hard over several days whether air exposure continues or not. There is very little shrinkage.

Question: What is the result of the chemical reaction(s) triggered by exposure to air - what is the chemical name or chemical formula for the cured state?

I rang the distributor but they don't know anything - they have no chemists. They buy it ready made and packaged from somebody else who in turn buys it from somebody else who in turn buys the ingredients in large quantities and mixes and packages it in accordance with some recipe that was devised decades ago - in other words they have no idea how it works. Dionne Court (talk) 14:22, 1 August 2023 (UTC)[reply]

Maybe rubber cement? From the description you've given, that sounds like it. --Jayron 32 14:26, 1 August 2023 (UTC)[reply]

It is nothing like rubber cement. It is colourless and eventually sets hard. Dionne Court (talk) 16:49, 1 August 2023 (UTC)[reply]

Many adhesives contain cyanoacrylate as a main ingredient and other ingredients to make it dry faster or be less bumpy or make it less liquidy. Acetates are hardeners, often used in nail polish. They would give the hardened glue a smoother surface. Acetone is a solvent. It is often used to keep mixtures from hardening. When exposed to air, the acetone quickly evaporates, leaving the hardened glue behind. If cyanoacrylate is the main ingredient, you would see the glue harden to a clear and smooth blob as the acetone evaporated and then the cyanoacryalte would harden white as it reacted with moisture in the air. It would be far more helpful is you mentioned the name of the product because there are many alternatives to cyanoacrylate. 12.116.29.106 (talk) 16:04, 1 August 2023 (UTC)[reply]

I would be surprised if it was cyanoacrylate (sold as "Superglue") as it forms a very strong bond on most surfaces, regardless of whether they are smooth or rough. One thing it won't bond to is skin, which cyanoacrylate will. Also, it has been sold since I was child, and that was >70 years ago. It is called "Tarzan's Grip" but I assume that is a locally branded name. I expect similar formula glues have various brands/names around the world. Note: the same company also sells cyanoacrylate adhesive, which is very considerably more expensive. Dionne Court (talk) 17:06, 1 August 2023 (UTC)[reply]

Anything like this? H&S datasheet here. Martin of Sheffield (talk) 17:22, 1 August 2023 (UTC)[reply]

This MSDS for "Tarzan's Grip All Purpose Glue" says it contains polyurethane. --Jayron 32 17:29, 1 August 2023 (UTC)[reply]

Another option is polyvinyl acetate, which is a super common general purpose glue ingredient. In the U.S. most of the Elmer's glue varieties are PVA-based adhesives. --Jayron 32 17:36, 1 August 2023 (UTC)[reply]

The averages of the proportions of acetone, ethyl acetate, and n-butyl acetate all match up, this checks out. Card Zero (talk) 21:14, 1 August 2023 (UTC)[reply]

Thanks Jayron. I had downloaded a much more recent MSDS than the one you found - it looks like the later one omitted the polyurethane for some reason - I assume by error. It didn't occur to me to try getting another version of the MSDS.

It would not be PVA as it is waterproof. PVA definitely is not. Dionne Court (talk) 03:40, 2 August 2023 (UTC)[reply]

No, definitely not Goy Gum. `Dionne Court (talk) 03:27, 2 August 2023 (UTC)[reply]

Swedish inventor Axel Karlson around 1922 made one of the first synthetic glues by dissolving Celluloid in Acetone. The resulting quick-drying glass-clear Karlsons Univarsalklister (universal glue) is still sold in northern Europe with swedish advertising slogans such as the pointed "Alla använder Karlsons klister utom jag, för jag är en åsna" (Everyone uses Karlson's glue except me because I'm an ass) and the unofficial "Om ditt hjärta nånsin brister, laga det med Karlsons klister" (If your heart should break asunder, make it whole with Karlson's wonder). The same or a similar glue is widely marketed by German manufacturer UHU. I suggest that a homemade version can be made by dissolving pieces of PMMA (Polymethyl methacrylate i.e. thermoplastic acrylic glass such as Plexiglas or Perspex) in acetone. Philvoids (talk) 14:42, 2 August 2023 (UTC)[reply]

One should be careful not to use Karlsons klister as a clyster. DuncanHill (talk) 23:02, 2 August 2023 (UTC)[reply]

August 2

Bear or person in suit

Would anyone here have any scientific evidence to conclude whether this is a real bear or a person in a bear costume?

Thanks, cmɢʟee⎆τaʟκ 13:58, 2 August 2023 (UTC)[reply]

@Cmglee This has been heavily covered in the recent news here in the UK and is now generally considered to be a genuine sun bear. Mike Turnbull (talk) 14:05, 2 August 2023 (UTC)[reply]

Unlike the joke where a 1-gorilla zoo hires a guy to be a gorilla and the increase in anthropomorphicness over the dead gorilla makes the zoo profitable again and one day he swings too high and screams in the lion area and the lion jumps on him and says shut up or we'll both be fired. Sagittarian Milky Way (talk) 15:01, 2 August 2023 (UTC)[reply]

Also note, the Wikipedia article sun bear states "Sun bears can expose the patch while standing on their hindfeet as a threat display against enemies." What we have, in that image, is clearly a pissed off sun bear, performing a threat display. --Jayron 32 16:34, 2 August 2023 (UTC)[reply]

Good joke! Thanks for the replies.

The articles I've read, including the above, do not give any evidence besides what the zoo spokesperson said (which they would lie about if they had gone through the trouble of dressing someone up).

It would also not be too difficult to add the patch to the costume if they were already making one.

I think the movement of the mouth looks very realistic, not having been around bears much, so that might be the key. However, the shape of the feet does look human.

Cheers, cmɢʟee⎆τaʟκ 17:17, 2 August 2023 (UTC)[reply]

Occam's razor my dude. Either 1) The zoo has, unremarkably to anyone, had a sun bear on display for years, and for just one day when that picture was taken, dressed up a man in a very convincing and realistic sun bear suit, and that was captured by a video on that one day, which no one of the hundreds of visitors noticed it looked like a man in a bear suit, except for this blurry video captured that man in a bear suit, and then every day after that the regular sun bear was again, unremarkably, on display, or 2) That's just a sun bear. --Jayron 32 17:30, 2 August 2023 (UTC)[reply]

Haha, thanks, @Jayron32. Cheers, cmɢʟee⎆τaʟκ 22:48, 2 August 2023 (UTC)[reply]

Here is a video from two years ago of a sun bear in an zoo that stands up in a very similar way, but in other parts displays behaviour that would be very hard for a human actor to mimic in a believable way. --Lambiam 17:42, 2 August 2023 (UTC)[reply]

Thanks, @Lambiam: first part is indeed very humanlike. Pity the bears look like they're suffering in subsequent parts though. Cheers, cmɢʟee⎆τaʟκ 22:56, 2 August 2023 (UTC)[reply]

The current issue of National Geographic has an article about an animal refuge in Jordan, and the picture of a Syrian black bear standing up looks similar to the one in question. Bears can walk on their hind feet if they're of a mind to do so. ←Baseball Bugs ^{What's up, Doc?} carrots→ 18:42, 3 August 2023 (UTC)[reply]

August 3

Star Trek ships

I have been watching Star Trek series, and I was wondering... many things in Star Trek lore are fine as sci-fi but completely impossible in real life (faster-than-light travel, teletransportation, matter replicators, etc). But what about the ships themselves? The Starship Enterprise and the Deep Space Nine (fictional space station) clearly dwarf the Starship HLS and the International Space Station, but would humanity be able to build such big things at some point in the future, or that is also just sci-fi daydreaming? Cambalachero (talk) 00:36, 3 August 2023 (UTC)[reply]

You may be interested in the books The Physics of Star Trek and The Science of Star Trek. Turner Street (talk) 13:26, 4 August 2023 (UTC)[reply]

Engineering speculations

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

This topic is going to require a great deal of speculation and may take us firmly into WP:NOTAFORUM territory, but then there are also legitimate references out there discussing these questions, I do believe, so perhaps we can ~~rationalize~~ justify it on those grounds. ;) That said, this is a multifaceted inquiry, but I'll try to address what I think are some very obvious points.

First off, much of what constitutes these fictional space vessels / space stations constitutes highly fictionalized technology. And not just at the usual level of handwaviness that you get with any space opera. Aside from a handful of franchises that go whole hog with the space fantasy (Star Wars being the most obvious big name), Star Trek is almost one of the softest of soft shows when it comes to its technical and scientific conceits. So obviously in that respect, there are huge chunks of this vessel that consists of things that do not (and in most cases, almost certainly will not ever) exist.

The next thing I believe kinda-sorta addressing your inquiry is the question of just constructing the basic shell of the vessels as represented. Even this would be no easy task, even assuming that we construct it out more conventional materials in the form of metals and plastics we are capable of mining, molding and engineering in the here and now. According to a search i just did online (which we might take with a grain of salt) the Enterprise D would weigh about 4.5 billion metric tons (and from a rough eyeball, Deep Space Nine about ten to twenty times that). I'll let our decent number of more mechanically adept contributors here crunch the math for how much lift force and fuel and loads with current/near-future technology that would come down to, for getting those materials into orbit (although speculatively speaking, some of it could be mined in space in the coming centuries).

Then of course there is the question of assembling said materials, and the amount of logistics involved with getting those people and/or automated machinery into near earth orbit and maintaining them to accomplish that task. That's to say nothing of how the economies of the world would have to be pretty much given over to the task of gathering, refining, and manufacturing the raw materials, and the impacts that would have for us socially, economically, and environmentally.

So, in short, no, at least within any immediate future. Even if by "could we make this ship" you actually mean a to-scale, non-functional model of one of these vessels, we simply lack the technology, infrastructure, materials, engineering know-how, and social impetus to pull the feat off within current technical limitations and with present day resources, or anything we can say with any confidence is on the horizon. It's very much guesstimation on my part, but I would say this sort of thing wouldn't be feasible (as a purely technical matter) for at least 500-1,000 years, even assuming a future in which we make pretty good speed in mining from, exploring, and even colonizing parts of the solar system. And it could easily end up being several times that long, even in an "optimistic" appraisal. And again, that's just for creating a basic, non-functional simulacra. SnowRise ^{let's rap} 04:37, 3 August 2023 (UTC)[reply]

4.5 gigatons seems like a very high multiple of the density of water for something only about 600-something meters in the longest dimension. Sagittarian Milky Way (talk) 06:27, 3 August 2023 (UTC)[reply]

A 29 cubic kilometer Borg cube would only weigh about twice as much at average 2023 ocean ship densities. Sagittarian Milky Way (talk) 06:34, 3 August 2023 (UTC)[reply]

Yeah, again, I caution against taking what the internet at large says about any of these figures at face value. Nevertheless, I think we can safely say that even if every nation on the face of the Earth reworked its economies and industries to pursuing this task, whatever the cost to quality of life on Earth in regards to both human thriving and the environment, it would still be a tall order to reliably but this material in space. And that's assuming we're talking about the most plentiful metals for our to-scale Enterprise model; not fantastical future alloys like 'duritanium' and 'transparent aluminum' (or for that matter, the materials we would use in a functional but much smaller space vessel that might actually be functional. SnowRise ^{let's rap} 09:11, 3 August 2023 (UTC)[reply]

Sapphire#Windows are common, and are substantially aluminum (a very plentiful metal). Card Zero (talk) 11:13, 3 August 2023 (UTC)[reply]

In a plausible future, the metal needed to construct large vessel hulls can be obtained by asteroid mining, and the vessel can be built in effectively zero-gravity (free-fall) conditions in robot-run ship factories orbiting the Sun, say between Mars and the asteroid belt. This will remove most of the obvious problems of building giant spaceships on Earth. --Lambiam 07:08, 3 August 2023 (UTC)[reply]

Well, as someone deeply respectful of the humanistic vision of Star Trek, I hate to be the rain on this particular parade, but I think we have to put a big ^{[citation needed]} next to some of that. All of this is theoretically possible in the broadstrokes, but technologies like asteroid mining and space-based manufacturing are highly speculative and not at all guaranteed to be as rosy as even the more "hard" and/or cynical of fiction writers like to posit. The Expanse for example is a highly accelerated timeline over what we can probably expect, with it's multiple planets, moons, and asteroids colonized in the next few hundred years, and it's relatively smaller amounts of space based industry and relatively simple ballistic vessel. Nevermind what Star Trek presents.

For me the more interesting part of Cambalachero's question is not the whether something roughly on the scale of these vessels can be constructed, or whether it would be, but rather the timeline. In that respect, there are a lot of unknowns, but enough knowns to be fairly certain that what we are talking about here (even considering likely technological advancements in materials science and computing that will make certain developments proceed along an exponential curve) is likely to be on a scale of thousands of years, rather than a couple hundred as contemporary sci-fi likes to present. And that's assuming that the technologies prove feasible. Asteroid mining may ultimately end up being inefficient. And even if lucrative, the timelines for transport will be considerable. Automation will be essential, since there are considerable physiological barriers to crew missions beyond the protection of the Earth's magnetosphere where radiation is a considerable threat (to say nothing of the rigors of years of weightlessness, privation, risks of hardware failure, and the limit squishy human bodies put on the maximum acceleration of vessels.

And all of this assumes that nuclear war, climate change, social unrest, and fierce competition between the nations of the Earth do not slow or even bring technological advancement to a halt, as surely they will do to at least some extent and in some combination. So "plausible"? Sure, in the broadest sense of the term. Certain? By no means. Likely? I think there's a big question mark there, and that's assuming we're prepared to give our descendants the leeway of a couple thousand years to colonize the solar system.

Your mention of weightless construction also raises another substantial issue to mind: these vessels could never function as vessels, by their basic design. Similarly, Deep Space Nine would never work as a space station, oriented as it is. Because artificial gravity, in the fantastical Star Trek "gravity plating" sense, does not exist and there's no particularly realistic reason to believe it ever will. And the Enterprise is not designed to facilitate gravity by constant acceleration, nor DS9 suited to create it with centripetal force.

That's kind of redundant on the previous statements about all of the more fantastical technology being absent, and this really having to come down to a "can we make something this big" as the only real question left here, of course, but it's worth mentioning in answering the OPs inquiry, because at some point you have to contend with the question of why and how such resources would be martialed. And even if you did have some speculative future culture devoted to the task of creating megavessels in space, they would not look anything like the Enterprise--nor the space stations likely to look like Deep Space Nine or those more conventional Federation giant mushroom dealies. SnowRise ^{let's rap} 09:00, 3 August 2023 (UTC)[reply]

We're not talking about tomorrow here. The question was about humankind's ability to build such big things at some point in the future. The first USS Enterprise (XCV 330) will be launched in 2123, so humankind still has some time left to develop the technology. The launch date of the canonical USS Enterprise (NCC-1701) is then still more than a century into the future. --Lambiam 09:14, 3 August 2023 (UTC)[reply]

There is a zero percent chance that our species will ever "launch" anything that looks or acts like the Enterprise as a functional spacecraft. It's design does not match with the needs of an actual vessel, local or interstellar, and it's entire conceit is based upon technologies that do not align even remotely with physical laws. The answer to the OP's question is an unequivocal no, a vessel like the Enterprise would be unfeasible, because very central aspects of its design are based upon fantastical 1960's era sci-fi concepts: even it's basic profile is impractical. As I said, there remains a very interesting area for speculation about whether we could construct something of the same basic scale and mass, and if so, at what point in time. But even that is most likely to be beyond our horizons for a lot longer than your average science fiction fan wants to believe.

And even in a speculative timeline of a few centuries from now, after concerted efforts at launching our colonization of the solar system (bear in mind we haven't even been to the moon in more than fifty years despite having the capacity!), we wouldn't build one giant ship like that when it makes much more sense for the ramping up of the exploitation of the solar system's resources to expend the same amount of material on thousands of (probably unmanned) smaller vessels, if we had the ability to manufacture and machine such precision craft in space.

Look, again, I hate to be the party pooper: I grew up partly on the era of super optimistic sci-fi of this flavour. But as I grew up and became more familiar with the real science and pragmatics involved, I realized that there was pretty yawning gulf between the Gene Rodenberry vision and the more restrained and realistic (but somehow equally romantic) vision of, say, a Carl Sagan vision of space exploration. I can't pretend phasers are in our future, but that doesn't mean I don't hold out a distant hope that we do in fact become 'space seeds'. SnowRise ^{let's rap} 10:42, 3 August 2023 (UTC)[reply]

Thousands of years? You don't think there'll be more progress in the time it took to go from ancient Egypt to now? Also, the OP didn't ask about ships that look like they came from Star Trek (why would they?), but "such big things", so WP:STRAWMAN arguments are moot. One distinct possibility is a generation ship to reach another star system. Clarityfiend (talk) 10:51, 3 August 2023 (UTC)[reply]

"Thousands of years? You don't think there'll be more progress in the time it took to go from ancient Egypt to now?"

No, I do think there will be progress, but there are limits to what developments in materials science can do in light of the logistics involved with the kind of endeavours we are talking about here. And I think science fiction gives people really unrealstic ideas about what even the most optimistic timelines looks like from the perspective of scientists and engineers.

Look, take Arthur C. Clarke for an example: he was arguably one of the "hardest" sci-fi authors of his generation, with much more formal background in physics and astronautics than his contemporaries (or present day authors for that matter). And yet even he, in his most famous work of fiction, had us regularly making commercial business trips to the moon and making exploratory manned surveys of Saturn decades ago. Whether from lack of perspective or a knowledge that discussion of more reasonable dates for certain technological and engineering thresholds would make the work less engaging for readers who want to believe they will live to see these things, science fiction writers and auteurs always massively accelerate the timeline for this kind of stuff, and it's really bled into the popular consciousness to create unrealistic expectation.

Also, do bear in mind that for most of that time from the end of classical era (i.e. 'Egypt'), technology developed rather slowly. We could very easily be at the apex of our present technological growth rate and about to hit a plateau. There are certain indicators that this is in fact happening: [3], [4], [5], [6], [7], [8], [9], [10], [11] (to take some examples from just the more conventional scientific press: this is actually an instance where I think primary sources/actual researchers are even more pessimistic/skeptical). Putting aside technological advancements, there's some really heavy math to deal with here: we have only so much raw material in terms of certain rare elements, and so much fuel to get it into orbit, and very pressing needs here on planet Earth competing for increasingly scarce resources. I'm not saying it won't happen. But if it does, it's going to take a looooong while longer than most laypersons and sci-fi aficionados want to believe. Sorry.

"Also, the OP didn't ask about ships that look like they came from Star Trek (why would they?), but "such big things", so WP:STRAWMAN arguments are moot."

Yeah..which is why the substantial majority of my responses to them have been very precisely about creating something of that scale/mass, since the actual Star Trek vessels are mostly pure fantasy. But Lambian was speculating about another topic: the realism of Star Trek's canonical timeline. And there's just no connection to reality whatsoever there.

"One distinct possibility is a generation ship to reach another star system."

Well you're going to think I'm a dedicated killjoy, but there's also a lot of reasons to believe that a generation ship is an infeasible option for reaching other star systems, from the mass:fuel ratios involved, to the ability to create sustainable and maintainable system while at high velocities, to the need for constant acceleration/deceleration at the back end, to shielding from interstellar materials at velocities where a grain of sand could blow out the front end of your vessel, to the impacts on human physiology of spending a lifetime in space, to the fact that we have substantial reason to believe that humans cannot safely gestate in such environments...the list goes on and on. The environs even just outside our solar system are extremely hostile and arduous. There are a number of scenarios for interstellar travel that now appear more realistic (though still highly speculative). Non-human drones or an artifical successor species are much more likely to be our first transplansts outside the solar system. But this is really an entirely different (and arguably longer) topic of discussion from the OP's question, and we're deep into the NOTAFORUM woods now, so I'm gonna stop here. SnowRise ^{let's rap} 12:26, 3 August 2023 (UTC)[reply]

You seem to keep overlooking that the question is not, "will it happen?", and also not, "is it advisable?", but merely, "will it, at some point in the future, become possible?". Also, less than two centuries ago engineers and scientists presented proofs that sustained powered flight by a flying machine was impossible, and a century before that they would have believed that almost instant communication with the other side of the globe was no more than the stuff of fairy tales. --Lambiam 13:09, 3 August 2023 (UTC)[reply]

I mean, yeah? But also, we have to approach completely fictional concepts on the terms of what they are. Unless there's strong empirical reason to believe in a particular development, there's no more reason to expect a given sci-fi contrivance from happening than there is any other random flight of fancy. Concepts that fly in the face of the normal operation of the laws of nature should be especially doubted, and even when it comes to (relatively) more mundane concepts, such as scaling up our surface to orbit lift capacity have to be considered in the light of reasonable projections and not random hopes of miraculous new developments in technology.

Yes, I suppose you can reasonably parse the OP's question to ask whether it is theoretically possible, in any permutation of the future, that we will be creating such massive constructs in space at some point along the timeline. But they also ended their query with "or is this sci-fi daydreaming", which suggests to me that their query is actually more nuanced, and they want a frank assessment of what the odds are and what the timeline might look like. And I stand by general assessment above: it's not the Star Trek timeline. It's probably not even The Martian's timeline. It's going to take us a while to get out there. It is one of my most earnest wishes for the future that it happen, but it's not a sure thing, based on the challenges we are facing in the near future. And to the extent that it may be more like than not (maybe) to happen on a long enough timeline, that timeline's almost certainly significantly longer than some people want to think.

Now if you'll all excuse me, I think I'll watch an episode of TNG before I turn in. :) SnowRise ^{let's rap} 13:27, 3 August 2023 (UTC)[reply]

Don't worry, we've got plenty of time to innovate up some science/fiction before the serious problems hit our planet. Nimur (talk) 16:40, 3 August 2023 (UTC)[reply]

Actual large structures that humans have constructed, and serious-ish proposals and scientific investigations into even bigger stuff: Megastructure, Megascale engineering. Actual easiest way by far to build a big spacecraft: Send up a robotic craft, with light sail for essentially infinite "free" maneuvering. Could slap some ion thrusters on too if you want. Already done, multiple times, so this is in the "existing and deployed tech" column. Send it to go land and set up shop on an asteroid. (Also with existing prior art.) Including deploying solar panels for nonstop supply of free energy. Voila, this is the founding of your new asteroid mining facility.

One of those, you're going to want to be an asteroid that you've determined to have the specific properties you want. This is going to be the core "hull" of your new craft. It's already a big old chunk of Stuff that's already there, for free. Why wouldn't you just use that thing literally lying around out there in space for anyone to come along and pick up? If you were building a car, from scratch, and came across basically a mostly-machined engine block and a big pile of metals and stuff, just lying around in the open, with a sign next to them saying "Free To Anyone", would you think about taking those to use in the making of your new car? Also in this analogy you are a little strapped for cash and having a devil of a time ordering materials and parts from anywhere.

Without very cheap spacelaunch, probably involving some non-rocket spacelaunch system, that makes it cheap and easy to chuck stuff up from Earth into orbit, the overwhelming limiting factor in anything "space" is the launch cost in hauling any bit of mass up and out of Earth's gravity well, because of the tyranny of the rocket equation. This is why spacecraft budgets spend huge sums on very fancy expensive complex multi-junction solar panels for power, that catch more photons. Because, that's still cheaper than having to haul up heavier cheaper panels atop a rocket. Down here in the dirt, most panels are the boringest lowest-tech simplest and least-efficient polycrystalline silicon, simply because those are cheapest and down here mass is not usually much of a limiting constraint. There's plenty of sunlight! Just put up more panels if you want more juice!

Thus your answer to "it's insanely expensive to get stuff into orbit" is, then don't haul up into orbit anything more than the bare minimum. Do everything, except what you absolutely can't, in space where you're already out of Earth's gravity well. Nothing about this is going to change ever until and unless getting mass into orbit from Earth's surface gets a lot cheaper. Because, gravity is physics and fundamental physical laws and you can't argue with it or convince it to be nice and turn down the gravity a bit on Earth so it's not so hard to launch rockets anymore, any more than you can argue with a brick wall to convince it to let you pass through it.

People's intuition doesn't "get" this stuff properly because it's not designed for these questions; it's "designed" for stuff like, is that a predator in those bushes, or, will this kill me if I eat it? It all looks so easy on the TV or computer screen. Those rockets look so pretty going up, like it's nothing at all. Except the overwhelming amount of mass they're carrying is just fuel, to enable them to haul more fuel to burn to haul more fuel to burn to haul...and eventually to get that tiny little payload at the top into orbit.

The asteroid belt has about 3% the mass of the Moon. Not ginormous but not nothing either. So your ballpark figure answer to is x feasible is, how much mass you need? Do the math. Numbers don't lie, though they can frequently be misinterpreted or tortured into confessing to things you want.

For slightly bigger lifts, we could put up a space elevator on the Moon today, with a tether made of a material such as Kevlar, because of the Moon's lower gravity. For a space elevator you need a counterweight at the "top". Know what makes a good counterweight? An asteroid of sufficient mass! Light sails give you "free" continuous thrust; it's just a matter of gradually altering its orbit until the Moon's gravity captures it (like what Mars might have done to get its moons). Energy is everywhere in the Solar System thanks to our life-giving star pouring it out nonstop. That's not your limiting factor. Mass and getting that mass to where you want it even if gravity would rather you not are. --47.155.41.201 (talk) 20:06, 3 August 2023 (UTC)[reply]

I hope you are not neglecting the fundamental truth that such an act is not entirely without precedent. Clearly looking at the largest transport we have built can be enlightening. For instance, the largest oil tanker ships in the world must surely come close to representing the true mass of the Enterprise. That is to say, that we have worked with something like that amount of metal previously. So what, per chance, would be the most egregious difficulty with performing the same metallurgy in space? Especially, if some location could be found for machining that did not happen to exist within the Earth’s gravity well. Yes, I would concede that the shape and dimensions of said craft should probably be altered to maximise efficiency, after all, professional scientists likely did not perform design work for whoever produced Star Trek. But clearly, the idea is sound, Especially after Nuclear Fusion is figured out in full. 31.94.62.178 (talk) 15:34, 4 August 2023 (UTC)[reply]

It will also be useful to add that we do not wish to try and rack our brains over artificial gravity or laser weaponry herein. The idea simply is to discuss the feasibility of a Sci-Fi style space ship that is comparable in size to the world’s largest ocean ships. The best way to discuss these things is to build off of knowledge already gained from the shipbuilding industry and its technologies, and then also throw in small amounts of knowledge about NASA spacecraft and other such things.

I would think about more efficient spaceplanes at first, with a goal of increasing the size and passenger capacity of these such vehicles. Also don’t forget smaller craft, some as small as 2 person capacity, seen in various Sci-Fi movies and series. I think the one thing that unites these craft and sets them apart from NASA craft is their speed and efficiency. Clearly today’s space agencies need to focus on new technologies such as Nuclear Fusion, Solar Power and other things that don’t involve liquids or gases that are burnt in an engine. They should also prioritise methods to shrink the size of the craft at first, with, a view to reducing the weight of them. This would then allow more people to be carried by a craft that weighs the same as today’s rockets, if these gains in efficiency can then be translated to larger craft.

Finally, we can be in a position to ask questions about larger craft, in particular space ships that will be built and launched from Earth’s orbit. The previous “pessimism-city” discussions that have now been collapsed, haven’t taken into account this more incremental approach. I also believe that speed increases are a must, as even 1% of the speed of light is ludicrously fast, fast enough to reach the Sun from Earth in less than 24 hours. Pablothepenguin (talk) 20:42, 4 August 2023 (UTC)[reply]

Would it at all be incorrect mention that on this Earth there exists many oil tankers, cruise ships, and aircraft carries that are blatantly larger than the claimed size of the Enterprise? How can the pessimists from earlier possibly claim otherwise? Yes we can build something that big. Yes the Earth does contain enough metal for the task. So why the pessimism and confusion? Is it really THAT hard to build that kind of metalwork in space? And is it that hard to imagine someone like Royal Caribbean or Carnival offering space cruises in 1,000 years for goodness sake!? Pablothepenguin (talk) 22:06, 4 August 2023 (UTC)[reply]

The nay-sayers are like the ones prior to 1903 who said man would never fly. ←Baseball Bugs ^{What's up, Doc?} carrots→ 22:09, 4 August 2023 (UTC)[reply]

Good point Pablothepenguin (talk) 23:34, 4 August 2023 (UTC)[reply]

August 4

List of youngest birth mother/father

Why these lists was deleted? 94.247.8.9 (talk) 15:45, 4 August 2023 (UTC)[reply]

Not sure what you're referring to, but if you want the youngest mother see Lina Medina EvergreenFir (talk) 15:50, 4 August 2023 (UTC)[reply]

See Wikipedia:Articles for deletion/List of youngest birth mothers --DB1729^talk 16:04, 4 August 2023 (UTC)[reply]

Thunder and the lightning

What is the physical explanation for the fact that thunder always follows lightning? AboutFace 22 (talk) 00:23, 5 August 2023 (UTC)[reply]

Revision as of 00:23, 5 August 2023 edit AboutFace 22 (talk \| contribs) Extended confirmed users 2,128 edits →‎Thunder and the lightning: new section Tag: New topic ← Previous edit		Revision as of 00:25, 5 August 2023 edit undo AboutFace 22 (talk \| contribs) Extended confirmed users 2,128 edits →‎Thunder and the lightning Next edit →
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	What is the physical explanation for the fact that ~~sunder~~ always follows lightning? [[User:AboutFace 22\|AboutFace 22]] ([[User talk:AboutFace 22\|talk]]) 00:23, 5 August 2023 (UTC)		What is the physical explanation for the fact that thunder always follows lightning? [[User:AboutFace 22\|AboutFace 22]] ([[User talk:AboutFace 22\|talk]]) 00:23, 5 August 2023 (UTC)