Difference between revisions of "2321: Low-Background Metal"

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In this comic, a team including [[Megan]] and [[Black Hat]] have invented {{w|time travel}}. Time travel is a common trope in science fiction, and such a discovery would be likely to change the world as we know it. However, Megan and Black Hat's machine requires the use of "low-background" metal, which is in short supply.
 
In this comic, a team including [[Megan]] and [[Black Hat]] have invented {{w|time travel}}. Time travel is a common trope in science fiction, and such a discovery would be likely to change the world as we know it. However, Megan and Black Hat's machine requires the use of "low-background" metal, which is in short supply.
  
Megan explains that, while delicate equipment is often shielded from radiation by lead, metals produced in modern times is contaminated by {{w|nuclear fallout}}, which means that the shielding itself has high enough radioactivity to interfere with highly delicate equipment.  In order to shield this equipment, "low-background metal" is salvaged from sunken Roman ships.  This metal, primarily lead, was used as ballast in the ships.  The Roman lead was produced before atmospheric nuclear tests occurred and therefore does not incorporate {{w|radionuclides}} from the air used in its manufacture. Because it has spent many centuries continually underwater, it is both shielded from radioactive particles in the air, and has had time for natural radioactivity to fade.
+
Megan explains that, while delicate equipment is often shielded from radiation by lead, metal produced in modern times is contaminated by {{w|nuclear fallout}} in the atmosphere, which means that the shielding itself has enough radioactivity to interfere with highly delicate equipment.  In order to shield this equipment, "low-background metal" is salvaged from sunken Roman ships.  This metal, primarily lead, was used as ballast in the ships.  The Roman lead was produced before atmospheric nuclear tests occurred and therefore did not have {{w|radionuclides}} in the air used in its manufacture. Because it has spent many centuries continually underwater, it is both shielded from radioactive particles, and has had time for natural radioactivity to fade.
  
Relying on shipwrecks of that age, which can be found and successfully salvaged, puts this material in extremely short supply, and Megan mentions that they have only enough for a single trip.  The team realizes (apparently at [[Black Hat]]'s suggestion), that the solution is to use their single trip to take modern military hardware back to the era of the {w|Roman Empire} and use it to sink multiple ships.  This would both provide for many more shipwrecks to salvage, and give the time a good idea of where those wrecks were, when they returned to modern times. They could also specifically target ships that were in waters that would relatively easy to conduct salvage operations. Such a solution would involve horrifying loss of human life, but would provide them with their needs. 
+
The number of shipwrecks of that age that can be found and successfully salvaged for metal is quite small, which puts this material in short supply. Megan mentions that they have only enough for a single trip.  The team realizes (apparently at [[Black Hat]]'s suggestion), that a solution is to use their single trip to take modern military hardware back to the era of the {w|Roman Empire} and use it to sink multiple ships.  This would both provide for many more shipwrecks to salvage, and give the team a good idea of where those wrecks were, when they returned to modern times. They could also specifically target ships that were in waters that are well-suited for salvage operations.  
  
 
In the real world, {{w|low-background steel|low-background ''steel''}} is sourced from ships made before the invention of nuclear weapons, such as the scuttled WWI fleet of the German Empire (not necessarily ancient Rome), and likewise, any lead mined before the development of nuclear weapons should also work for the time machine, such as munitions made before or during the World Wars.  Black Hat may have chosen ancient Rome as their destination because they have advanced industry related to lead production (used so widely in Roman pipeworks that their word for lead, ''plumbum'', survives in the English word "plumbing") but no aircraft or anti-aircraft artillery.  (And also his twisted sense of humor.)
 
In the real world, {{w|low-background steel|low-background ''steel''}} is sourced from ships made before the invention of nuclear weapons, such as the scuttled WWI fleet of the German Empire (not necessarily ancient Rome), and likewise, any lead mined before the development of nuclear weapons should also work for the time machine, such as munitions made before or during the World Wars.  Black Hat may have chosen ancient Rome as their destination because they have advanced industry related to lead production (used so widely in Roman pipeworks that their word for lead, ''plumbum'', survives in the English word "plumbing") but no aircraft or anti-aircraft artillery.  (And also his twisted sense of humor.)

Revision as of 21:03, 17 June 2020

Low-Background Metal
The only effect on the history books were a few confusing accounts of something called 'Greek fire.'
Title text: The only effect on the history books were a few confusing accounts of something called 'Greek fire.'

Explanation

Ambox notice.png This explanation may be incomplete or incorrect: Created by a TIME TRAVELER. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.
If you can address this issue, please edit the page! Thanks.

In this comic, a team including Megan and Black Hat have invented time travel. Time travel is a common trope in science fiction, and such a discovery would be likely to change the world as we know it. However, Megan and Black Hat's machine requires the use of "low-background" metal, which is in short supply.

Megan explains that, while delicate equipment is often shielded from radiation by lead, metal produced in modern times is contaminated by nuclear fallout in the atmosphere, which means that the shielding itself has enough radioactivity to interfere with highly delicate equipment. In order to shield this equipment, "low-background metal" is salvaged from sunken Roman ships. This metal, primarily lead, was used as ballast in the ships. The Roman lead was produced before atmospheric nuclear tests occurred and therefore did not have radionuclides in the air used in its manufacture. Because it has spent many centuries continually underwater, it is both shielded from radioactive particles, and has had time for natural radioactivity to fade.

The number of shipwrecks of that age that can be found and successfully salvaged for metal is quite small, which puts this material in short supply. Megan mentions that they have only enough for a single trip. The team realizes (apparently at Black Hat's suggestion), that a solution is to use their single trip to take modern military hardware back to the era of the {w|Roman Empire} and use it to sink multiple ships. This would both provide for many more shipwrecks to salvage, and give the team a good idea of where those wrecks were, when they returned to modern times. They could also specifically target ships that were in waters that are well-suited for salvage operations.

In the real world, low-background steel is sourced from ships made before the invention of nuclear weapons, such as the scuttled WWI fleet of the German Empire (not necessarily ancient Rome), and likewise, any lead mined before the development of nuclear weapons should also work for the time machine, such as munitions made before or during the World Wars. Black Hat may have chosen ancient Rome as their destination because they have advanced industry related to lead production (used so widely in Roman pipeworks that their word for lead, plumbum, survives in the English word "plumbing") but no aircraft or anti-aircraft artillery. (And also his twisted sense of humor.)

The title text refers to Greek fire, which was an incendiary weapon invented and employed by the Byzantine empire. It was a flammable liquid used in naval combat to set fire to enemy ships, but the details of its manufacture and deployment are vague. As it was a closely-guarded military secret, many of the details have been lost to time, and modern chemists have only been able to develop educated guesses of what it probably was. Randall proposes a rather outlandish alternative hypothesis: that all records of Greek fire were actually in reference to the modern weapons used by the time travelers.

Transcript

Ambox notice.png This transcript is incomplete. Please help editing it! Thanks.
[Megan, Black Hat and Cueball stand around a time machine on a table.]
Megan: Our time machine works.
Megan: But we're almost out of low-background metal.
Cueball: What's that?
[Close-up on Megan.]
Megan: Modern metal is contaminated by fallout from nuclear testing, and lead also has natural radioactivity that fades over time.
Megan: To shield sensitive equipment, physicists use lead from sunken Roman ships.
Megan: But shipwreck lead is hard to find.
[Zoomed back out to the group. Megan is facing Black Hat, who has his hand on his chin.]
Black Hat: How much do we have?
Megan: Enough for one trip through time.
Black Hat: Hmmm...
[The scene changes to the group having traveled through time. They are in a helicopter, with Megan piloting, Cueball as a passenger, and Black Hat firing a flamethrower at a Roman ship. The sailors on the ship are alarmed and attempting to escape. Two already-burning ships can also be seen, with one almost completely sunk.]
Flamethrower: FWOOOSH


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Discussion

Spoiler Alert for Avengers Endgame next comment 162.158.75.60 20:36, 18 June 2020 (UTC)

I can't help but notice that the basic premise of this comic is very much like the reason for going back to 1970 in Avengers: Endgame, when they needed more Pym particles for time travel. I wonder if Randall re-watched it again recently? — KarMann (talk) 17:10, 17 June 2020 (UTC)
Whoa! Spoiler alert! Disney Plus won't have Infinity War until next week. I'm not watching them out of order! Mathmannix (talk) 12:16, 18 June 2020 (UTC)

Oh, that's new to me, that they use roman ships to get to higher quantities of lead. For Steel they use German ships. after world war I, the german high seas fleet was captured and put under arrest in scottish waters. To not allow the enemy to utilize the ships, they all sank themselfes. wikisource --Lupo (talk) 05:46, 18 June 2020 (UTC)

Is there any evidence of Roman ships using lead for ballast? I know it was used as a structural metal and utility metal (sheathing, seam sealing, anchors, tools). It was also carried as cargo. But it seems likely that Roman lead was too expensive to be used as ballast, particularly compared to, say, rocks or concrete. (Note that loading cargo low in the hull is not ballast, cargo is there because you want to move it, ballast is there only to keep the boat upright.)173.245.54.187 18:08, 19 June 2020 (UTC)

The Romans used lead as a sweetener, I think they had plenty. --162.158.106.178 08:06, 20 June 2020 (UTC)
The references I found to modern use of Roman lead referred to ingots from Roman cargo. Controversy over the use of Roman ingots to investigate dark matter and neutrinosLead Use on Roman Ships and its Environmental Effects 162.158.106.106 21:04, 20 June 2020 (UTC)

Drawing

There's one leg of the time-machine missing from the 3rd panel. (or is it the side of a base?) --162.158.155.126 19:57, 17 June 2020 (UTC)


Mined lead

Pb-210 (half-life 20.4 years) is a decay product of radon, and thus accumulates everywhere that is exposed to the atmosphere or where radon seeps from the ground. I suspect it could be a contaminant in lead from some lead mines, but wasn't able to find any references ShadwellNH (talk) 20:00, 17 June 2020 (UTC) Paul

Pb-210 is mentioned in Controversy over the use of Roman ingots to investigate dark matter and neutrinos. 162.158.106.106 21:04, 20 June 2020 (UTC)

One use only?

The way I understand it, the time machine is one-use unless you find other Low-Background Metal. If you find it, you can make more trips. It would appear that the trip is successful. --188.114.103.129 01:31, 18 June 2020 (UTC)

So you'd say a car is also one-use, unless you find a gas station? 162.158.158.167 08:51, 18 June 2020 (UTC)

(out of chrono... I am 162.158.158.167): No, I'd say that this is not a one-use time machine, so it's wrong to compare it to one-use time machines. Luckily, someone else changed the text already. --188.114.102.22 13:39, 19 June 2020 (UTC)
"I am 162.158.158.167" no you're not.
No, but if the parts it was made of had to be replaced after every trip, I definitely would. 172.69.70.117 16:59, 18 June 2020 (UTC)
Sure, but the ability to rebuild the car with completely new material doesn't turn it into a multi-use car. 141.101.98.130 04:11, 19 June 2020 (UTC)

Real life use of this lead?

Does anyone know whether there is any truth whatsoever to scientists using lead from sunken ships to shield delicate equipment? Obviously not time machines, but there are some pieces of equipment that might be sensitive to radiation.

Also, would lead that was in the ocean actually be safer from nuclear fallout than lead that was underground and mined after the nuclear testing ended? 108.162.216.172 03:31, 18 June 2020 (UTC)

Yes. At least it is done with steel. [1][2][3] 172.69.33.129 04:50, 18 June 2020 (UTC)
Yes the water is a better insulator than air. Also the fallout would be partially absorbed by plants/animals before reaching the ocean bottom. 162.158.123.155 16:51, 19 June 2020 (UTC)
Low Background Lead is also used, mentioned in the Good article. The equipment that need this stuff is mostly radiation sensors, very precise ones that can detect even smallest amounts of radiation. And for the last Question, you can't find pure natural lead, its mostly contaminated with radioactive elements (most lead in the universe results from decay chains). And common lead is made through recycling. Ancient lead from roman ships had enough time for the radioactive elements to decay into stable lead. --141.101.105.114 06:12, 18 June 2020 (UTC)

May be complicated

The 1968 Story Hawk among Sparrows discusses the problems modern war hardware may have when used against old tech. -- 141.101.76.82 07:39, 18 June 2020 (UTC)

This was also part of the premise of the 1980 movie "Final Countdown", when the aircraft carrier Nimitz shows up in the Pacific Ocean on December 6, 1941. Nutster (talk) 13:38, 18 June 2020 (UTC)
Biggles: The Movie had a WW1 flying ace take a 1980s helicopter (ostensibly unarmed, except fortuitously/inevitably against the Big Bad Weapon) back to his era, thanks to a Time-Twin plotline. Thus, IIRC it only did well to defend against era-local aicraft by the mythical skill of the eponymous pilot, and was handily lost once the temporal-trickery job was finally accomplished. If you enjoy that era of kitcsh then I'd suggest you not pass up a viewing, even if not actually seek it out. 141.101.98.130 17:11, 18 June 2020 (UTC)
  • I am also mildly disappointed that the helicopter is not Airwolf. Nutster (talk) 03:11, 19 June 2020 (UTC)

Safer alternative?

They could just send a cache of modern lead back in time and wait till it cools down. 141.101.76.82 06:30, 19 June 2020 (UTC) Naah, that would totally violate causality. Not to mention that you'd now have the exact same atoms existing in two spatial places at the same time. That could quite easily lead to the Earth being engulfed in a giant wormhole. Cellocgw (talk) 10:05, 19 June 2020 (UTC)

Add Topic

Can we Add Topic with impunity now? WOOOPEEEE!108.162.216.216 10:45, 19 June 2020 (UTC)108.162.216.216 10:48, 19 June 2020 (UTC)

Links tutorial

In case the IP editor who came by recently (to try to resolve the issue with the link [[wikia:w:c:transcripts:Back to the Future|this transcript]], which currently fails due to excessive redirects), the following is a quick(ish) guide to the basic types of link-markup, here, that some might find interesting:

  • For a plain URL, you could just leave it. You wanted to replace the unmanagable wikia link with https://en.wikipedia.org/wiki/Back_to_the_Future_(film) and, without any additional markup, it appears as its own literal text that links. (Generally considered untidy, of course, but there are times when it would be Ok.)
  • If you surround a URL with single []s, e.g. something like [https://en.wikipedia.org/wiki/Back_to_the_Future_(film)] <-this then it looks something like [4] <-this, which is usable but often still a bit dialogue breaking.
    • The replacement text version puts a space between URL and the text. something like [https://en.wikipedia.org/wiki/Back_to_the_Future_(film) this] will appear something like this, and is the best way to represent most external URLs.
  • For something internal/cross-wiki you can use double[[]]s something like [[2320: Millennium Problems]] <-a link to the prior explanation which is thus something like 2320: Millennium Problems <-a link to the prior explanation.
    • If I'd have linked to 2321: Low-Background Metal then, when seen from that page, e.g. via the Page Discussion section embedded within it, then it'll 'intelligently' not link, just highlight... can be very confusing. But 2321 and Low-Background Metal (because they are separate pages that redirect back again) will work, if that's what you want.
    • It is good practice to use the "Number: Title" page and text, when it is a clear link to another comic page (or similar) but if you want to use alternate text, use the pipe, e.g. something like [[2320: Millennium Problems|a link to the prior page]] produces something like a link to the prior page, thus.
    • I've been making sure the URL 'replacement' characters, above, are unreplaced. e.g. spaces instead of the underline. But you can retain the underlines (or other ASCII replacement codes, if any). It might look funny to see 2320:_Millennium_Problems, but it will work. And if it's overriden by replacement text then it matters much less!
    • Technically, the [[wikia:w:c:...]] notation should work, but in this case it has broken (possibly well after originally being written).
  • However, for wikipedia links (and some other common external places) you have another option. The {{w}} template can be written as something like {{w|Back_to_the_Future_(film)}} or {{w|Back to the_Future (film)}}, to appear as something like Back_to_the_Future_(film) or Back to the Future (film) (note the preferable latter version, insofar as not displaying any URL-friendly character replacement).
    • And add "<pipe><replacement text>", of course, so that something like {{w|Back_to_the_Future_(film)|first link}} or {{w|Back to the Future (film)|second link}} will show up as something like first link or second link, looking nicer (generally) in both editor and rendered page.
    • For 'media' under the wiki you can use a number of formats [[File:Back to the Future.jpg|this version]] and {{w|File:Back to the Future.jpg|this version}} will give this version. Unfortunately (or not, if that's what you intend,) in this case [[File:Back to the Future.jpg]] finds the local comic image with this name and embeds it as an image. Which is why I would suggest using {{w}}, when appropriate, rather than relying upon a seemless interwiki behaviour for anything other than articles. But you start to get into much more advanced mediawiki notation at this point.

Hope this helps someone. Even if not the editor who passed by earlier and had so much trouble! 172.69.194.194 14:55, 1 November 2023 (UTC)