Wikipedia:Reference desk/Archives/Science/2023 September 23

= September 23 =

How to simultaneously fire every neuron?
Hello, I am working on the concept phase of a device that I intend to expand brain power by firing every neuron at the same time. We currently use no more than 15% of our brain’s processing capacity, leaving the other 85% of neurons idle. This device would bring that number up to 100%, thus improving overall speed and performance. What kind of stimulation would cause all neurons to fire simultaneously? It seems like some pharmaceuticals unlock brain power, but I imagine something immediate, like electrical or possibly magnetic energy that would basically flip one switch for all neurons to activate. Gliffor32XD (talk) 03:53, 23 September 2023 (UTC)
 * It was never true to claim that "We currently use no more than 15% of our brain’s processing capacity". HiLo48 (talk) 04:15, 23 September 2023 (UTC)
 * Yes, that has been soundly debunked. As to how to fire all the neurons at once, I'm thinking that might happen in an electric chair. ←Baseball Bugs What's up, Doc? carrots→ 04:24, 23 September 2023 (UTC)
 * This question was previously asked and answered at Reference desk/Archives/Science/2023 February 11.- gadfium 04:26, 23 September 2023 (UTC)
 * Asked by a sockpuppet of a globally locked former contributor. Not much brainpower here... AndyTheGrump (talk) 05:31, 23 September 2023 (UTC)

soil bearing capacity
Hi. This US site lists soil bearing capacity ranging from 2000 PSI to 12000 PSI, which is 13789 kPa to 82737 kPa in metric units.

This UK site lists soil bearing capacity ranging from 75 kPA to 600 kPa.

Clearly they are using very very different measurement methods, and thus resulting in two very very different scales. These two scale are not directly comparable to each other (as far as I can see).

What is the difference in the measurement method that results in such a large difference in the resultant scale?

(Obviously these scales are arbitrary so there is no right or wrong here. I am not suggesting that one of these scale is somehow better than the other, or that one of them is more preferable than the other. I just want to know why they are different.) Liberté2 (talk) 18:04, 23 September 2023 (UTC)
 * Doesn't the US one give pounds per square foot? 12,000 pounds per square foot is 574.6 kPa. Abductive  (reasoning) 20:51, 23 September 2023 (UTC)
 * Right you are. That was a terribly embarrassing mistake on my part, haha. Liberté2 (talk) 22:39, 23 September 2023 (UTC)
 * Liberté2 (talk) 22:39, 23 September 2023 (UTC)

air concrete
Hi. I know nothing about concrete (as clearly evident by my embarrassing question above).

Before today, I was under the (uninformed) impression that air in concrete is a very bad thing. Then today I came across this PDF which explained that air is intentionally kept in concrete in some regions. I did not know that before. This is also covered in the WP article Air entrainment.

Roughly in which region or states in the US is this done? The PDF is from the Federal Highway Administration and they build highways all across the US, so presumably they have some sort of map or list or guidance on where this should or should not be done.

I googled "Air-Entraining Admixtures map", "Air-Entraining Admixtures states", and "Air-Entraining Admixtures region" and nothing useful came up. Liberté2 (talk) 22:55, 23 September 2023 (UTC)
 * For any topic as broad as "concrete", it's a fair guess that everything that is possible is done sometimes, for some purpose, and will have some (maybe very narrow) usefulness in some obscure situation.
 * Concrete is dense. So there are many situations where a lighter concrete, formed by the inclusion of gas bubbles, is useful. It might lose strength, yet gains strength / weight ratio, so is still useful.  This is becoming a major (major!) topic in the UK at present, as we finally act on the amount of RAAC (Autoclaved aerated concrete is the more useful article) which is reaching its end of life.
 * In the situation you link, it's an even more obscure case. Trading off a few % loss in strength gives a useful increase in longevity against Winter freeze-thaw damage, a major problem for civil engineering in the more northerly states. Andy Dingley (talk) 08:41, 24 September 2023 (UTC)
 * They should definitely have done better checks on how well protected the steel rods inside were before using it so widely rather than now having to replace it all. Concrete is used for everything is about right though! I remember how surprised I was when I was told a dredging barge I was looking at was made of concrete! And it had been happily working away for nearly a century. The reinforcement in that was much better done than in those buldings made fifty years ago. NadVolum (talk) 10:32, 24 September 2023 (UTC)
 * Even the Romans used concrete, some of which survives to the present day.... Mike Turnbull (talk) 14:16, 24 September 2023 (UTC)
 * According to a recent YouTube video made by an experienced builder, problems with RAAC installations in the UK, particularly those from the 1960s and -70s, are not due to the material itself, but to its use for less appropriate purposes (like unpitched roofs, which inevitably leak and allow water into the porous concrete to rust the steel rebar) and to hasty inaccurate building work that resulted in many horizontal RAAC panels being inadequately supported at their ends by walls an inch or more out of true, leading to excessive shear forces that cause them to crack.
 * The presenter contrasted these with Rome's Pantheon, a huge unsupported dome built, skilfully, with Roman concrete nearly 2000 years ago that is still sound and safe today (which is why Mike Turnbull's post above reminded me of the video). {The poster formerly known as 87.81.230.195} 51.198.107.25 (talk) 15:24, 25 September 2023 (UTC)


 * There are concretes such as kiln brick where air bubbles are intentionally incorporated into concrete for temperature insulation. Such concrete is usually structurally very brittle while allowing a thousand degrees of temperature difference to room air temperature right next to it (either Fahrenheit or Celsius, take your pick).  85.76.21.190 (talk) 14:58, 27 September 2023 (UTC)


 * Air in concrete is of little consequence, but moisture (resulting from rain water) certainly is. Of course, this applies to all construction materials:  Wet timber decomposes, wet steel rusts, etc.
 * Wet masonry (Stone Henge, Cheops Pyramid, Gothic cathedrals) generally is not critical. The lintels atop the sarsen stones on Salesbury Plain have not - well, not all - collapsed in 3.4 millennia.
 * The problem is reinforced concrete, a compound material where steel bars / meshes are embedded in concrete (= an aggregate of sand and pebbles bound by cement). In the case of aerated panels these structural elements also contain air bubbles to decrease the weight / reduce thermal transmission.
 * When water is absorbed, there may be two results:
 * 1	Cement, which acts like a glue to the aggregate, is - simplified - washed out.
 * 2	Reinforcing rods will oxidise / rust.
 * As a result, the load bearing capacity of the structural element is reduced and the item fails under structural load. Generally, aerated concrete is used for panels which simply support their own weight.  This weight suffices to cause damage and injuries.
 * --Cookatoo.ergo.ZooM (talk) 16:31, 27 September 2023 (UTC)

Music lost to time
Hi all. Listening to Mazzy Star's "Fade into You" got me thinking just how nicely it captured that 90s feeling. Then I wondered if people would be able to listen to it a thousand years down the line. Let's assume for a second that streaming platforms will exist in 3000: would our successors be able to listen to Hope Sandoval the way I do now? Will the server have to re-upload a fresh recording some time between now and 3000 for millions to stream? Where and how is the initial studio recording stored? Does the recording decay? If the record is copied for preservation to another device, will the quality greatly diminish for the copy of a copy's copy? What's the best medium to save a music file and is it financially viable?

Too many questions condensed into one: If records do fade away and their near-eternal storage is financially unsound, or future technology is unable to reproduce current media just like we're already struggling with VHS, will the majority of present-day music eventually become lost to time?

Thank you. Splićanin (talk) 23:05, 23 September 2023 (UTC)
 * I take it you're talking about digital recordings. What about older technologies, like 78 RPM phonograph records? They were being produced as recently as the 1950s, but it's pretty hard to find a machine that will play them. ←Baseball Bugs What's up, Doc? carrots→ 00:48, 24 September 2023 (UTC)
 * A quick search on Amazon returns: 'over 6,000 results for "78 rpm record player"'. Pretty well all turntables I've see recently are 33/45/78.  You make a fair point for digital media however. Martin of Sheffield (talk) 08:46, 24 September 2023 (UTC)
 * You're asking for speculation, which we can't really do here. However, the general concept you're looking for can be researched on a number of articles, including Digital preservation and Data preservation, Digital permanence, Media preservation, and many others. In other words, it's something that a lot of people have thought about (including the Norwegians). I'm 99% sure we have an article specifically on the specific struggle with the obsolescence of the software/hardware used to read the data (e.g. VHS tapes), but it's evading me. Matt Deres (talk) 02:46, 24 September 2023 (UTC)
 * Digital dark age and media preservation talk about the issues of hardware and software obsolescence to some extent although the former not in relation to VHS tapes. Nil Einne (talk) 03:32, 24 September 2023 (UTC)


 * When you look at the history of music, what has kept certain music alive through the centuries without technology is not just sheet music, but also its status as part of a musical repertoire. It is also quite common for popular music to fall out of this repertoire and go missing and unheard, only to be brought back a century or so later.  Even without technology to preserve this music, I can assure you, the music behind "Fade into You" doesn't belong solely to 1994 (although it certainly felt like it at the time, because you couldn't escape it).  It belongs to the sphere of the mind, which means as long as musicians are still around in the future, it is likely that many of them will cover the tune and keep it alive. As odd as this might sound, it's not unheard of.  A lot of music is known to contain bits and pieces of melodies and arrangements from older folk music.  Much of that folk music is now lost, but survives in part through its incorporation into newer pieces.  Given the simplicity and general tone of "Fade into You", that's how it will likely survive as well, and newer musicians will rediscover it and call it their own, as they always do. Viriditas (talk) 21:45, 24 September 2023 (UTC)
 * Products of culture, like books, films, architecture, paintings, drawings and the like, including music, tend to inevitably get lost as time goes by. It is inevitable, sadly. Very few thought about long-term preservation of such products of culture hundreds of years ago, and right now there are countless of probably interesting and maybe groundbreaking works that have been lost. It is impossible to keep and save everything, sad as it might be. --Ouro (blah blah) 17:34, 26 September 2023 (UTC)