https://www.explainxkcd.com/wiki/api.php?action=feedcontributions&user=108.162.237.24&feedformat=atomexplain xkcd - User contributions [en]2024-03-28T17:49:11ZUser contributionsMediaWiki 1.30.0https://www.explainxkcd.com/wiki/index.php?title=2321:_Low-Background_Metal&diff=1935382321: Low-Background Metal2020-06-17T19:10:14Z<p>108.162.237.24: </p>
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<div>{{comic<br />
| number = 2321<br />
| date = June 17, 2020<br />
| title = Low-Background Metal<br />
| image = low_background_metal.png<br />
| titletext = The only effect on the history books were a few confusing accounts of something called 'Greek fire.'<br />
}}<br />
<br />
==Explanation==<br />
{{incomplete|Created by a TIME TRAVELER. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}<br />
In this comic, [[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 metal with little to no radiation, meaning currently available metals are too passively radioactive for safe use. Noting that the only way they can obtain this metal, which is presumably consumed upon use of the machine, is by salvaging it from ancient Roman ships, they use the machine to travel back in time to when the Roman Empire was at its height in order to sink its vessels and in turn create more Roman lead for them to use.<br />
<br />
The "low-background metal" salvaged from sunken Roman ships is primarily lead, which was used as ballast in the ships and is now used as shielding from rare event nuclear and particle physics detectors. The Roman lead was produced before atmospheric nuclear tests occurred and therefore does not incorporate {{w|radionuclides}} from the air used in its manufacture.<br />
<br />
The title text refers to {{w|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.<br />
<br />
==Transcript==<br />
{{incomplete transcript|Do NOT delete this tag too soon.}}<br />
:[Megan, Black Hat and Cueball stand around a time machine on a table]<br />
:Megan: Our time machine works.<br />
:Megan: But we're almost out of low-background metal.<br />
:Cueball: What's that?<br />
<br />
:Megan: Modern metal is contaminated by fallout from nuclear testing, and lead also has natural radioactivity that fades over time.<br />
:Megan: To shield sensitive equipment, physicists use lead from sunken Roman ships.<br />
:Megan: But shipwreck lead is hard to find.<br />
<br />
:Black Hat: How much do we have?<br />
:Megan: Enough for one trip through time.<br />
:Black Hat: ''Hmmm...''<br />
:[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 sunken.] <br />
:Flamethrower: FWOOOSH<br />
<br />
<br />
{{comic discussion}}<br />
<br />
[[Category:Comics featuring Black Hat]]<br />
[[Category:Comics featuring Cueball]]<br />
[[Category:Comics featuring Megan]]<br />
[[Category:Time travel]]</div>108.162.237.24https://www.explainxkcd.com/wiki/index.php?title=Talk:2319:_Large_Number_Formats&diff=193284Talk:2319: Large Number Formats2020-06-12T22:22:43Z<p>108.162.237.24: /* Scientist avoiding rounding */</p>
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<div><!--Please sign your posts with ~~~~ and don't delete this text. New comments should be added at the bottom.--><br />
<br />
== Scientist avoiding rounding ==<br />
<br />
Would love an explanation of the scientist avoiding rounding one. Would make sense to me with 2.525997..., but as 2.5997... I'm at a loss!<br />
<br />
<br />
(The above was posted (anonymously?) seconds before I could get mine in, so here it is in the original format.)<br />
<br />
This is probably completely irrelevant but it seems Randall made a small typo when trying to show a "Scientest trying to avoid rounding up."<br />
I assume it should be 2.525997*10^13. It seems he left out a 5 and a 2 and I say such because whether he forgot the 52 or 25 is up for debate.<br />
<br />
Relevant screenshot: [[https://i.imgur.com/NrvOivy.png]]<br />
<br />
Also, if I'm just being completely daft and am missing something completely, please feel free to criticize me harshly and I'll go back to my little hideyhole. [[Special:Contributions/108.162.237.24|108.162.237.24]] 22:21, 12 June 2020 (UTC)</div>108.162.237.24https://www.explainxkcd.com/wiki/index.php?title=Talk:2319:_Large_Number_Formats&diff=193283Talk:2319: Large Number Formats2020-06-12T22:22:10Z<p>108.162.237.24: /* Scientist Cont. */</p>
<hr />
<div><!--Please sign your posts with ~~~~ and don't delete this text. New comments should be added at the bottom.--><br />
<br />
== Scientist avoiding rounding ==<br />
<br />
Would love an explanation of the scientist avoiding rounding one. Would make sense to me with 2.525997..., but as 2.5997... I'm at a loss!<br />
<br />
<br />
(Was posted seconds before I could get mine in, so here it is in the original format.<br />
<br />
This is probably completely irrelevant but it seems Randall made a small typo when trying to show a "Scientest trying to avoid rounding up."<br />
I assume it should be 2.525997*10^13. It seems he left out a 5 and a 2 and I say such because whether he forgot the 52 or 25 is up for debate.<br />
<br />
Relevant screenshot: [[https://i.imgur.com/NrvOivy.png]]<br />
<br />
Also, if I'm just being completely daft and am missing something completely, please feel free to criticize me harshly and I'll go back to my little hideyhole. [[Special:Contributions/108.162.237.24|108.162.237.24]] 22:21, 12 June 2020 (UTC)</div>108.162.237.24https://www.explainxkcd.com/wiki/index.php?title=Talk:2319:_Large_Number_Formats&diff=193282Talk:2319: Large Number Formats2020-06-12T22:21:24Z<p>108.162.237.24: </p>
<hr />
<div><!--Please sign your posts with ~~~~ and don't delete this text. New comments should be added at the bottom.--><br />
<br />
== Scientist avoiding rounding ==<br />
<br />
Would love an explanation of the scientist avoiding rounding one. Would make sense to me with 2.525997..., but as 2.5997... I'm at a loss!<br />
<br />
== Scientist Cont. ==<br />
<br />
(Was posted seconds before I could get mine in, so here it is in the original format.<br />
<br />
This is probably completely irrelevant but it seems Randall made a small typo when trying to show a "Scientest trying to avoid rounding up."<br />
I assume it should be 2.525997*10^13. It seems he left out a 5 and a 2 and I say such because whether he forgot the 52 or 25 is up for debate.<br />
<br />
Relevant screenshot: [[https://i.imgur.com/NrvOivy.png]]<br />
<br />
Also, if I'm just being completely daft and am missing something completely, please feel free to criticize me harshly and I'll go back to my little hideyhole. [[Special:Contributions/108.162.237.24|108.162.237.24]] 22:21, 12 June 2020 (UTC)</div>108.162.237.24https://www.explainxkcd.com/wiki/index.php?title=2310:_Great_Attractor&diff=1923972310: Great Attractor2020-05-23T01:32:40Z<p>108.162.237.24: </p>
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<div>{{comic<br />
| number = 2310<br />
| date = May 22, 2020<br />
| title = Great Attractor<br />
| image = great_attractor.png<br />
| titletext = Living in the southern hemisphere was nice because I could jump extra high, but I like it here too. Besides, if I ever want to move back, I can just curl up in a ball and wait!<br />
}}<br />
<br />
==Explanation==<br />
{{incomplete|Created by a Greatly Attractive SpaceBOT. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}<br />
<br />
[[Cueball]] comments on the fact that as summer approaches, the sun rises earlier and sets later, a common topic of conversation, especially to complain that it is still light at times of day where you are used to it being dark out. [[Beret Guy]] comments that he fell off of the wall this morning, a seemingly unconnected topic.<br />
<br />
People will often complain about falling out of bed as an indicator of having slept badly. The later sunset is often linked to worsened sleep [https://www.insider.com/why-its-hard-to-sleep-in-the-summer-2018-6]. However, Cueball didn't fall from the bed, he fell from the wall. While being able to figure out he's talking about his worsened sleep, Cueball is understandably confused, so Beret Guy clarifies. <br />
<br />
Beret Guy is strongly affected by the The {{w|Great Attractor}}, a large gravitational anomaly that influences the galaxies near it, but is difficult to observe directly. Beret Guy claims that the great attractor pulls on him unusually hard, which could be another one of his strange powers. This attraction, while not overpowering the gravity of the earth, (as he states that he can only "Jump extra high" in the Title Text) affects his life greatly, such as allowing him to sleep on walls. While 'normal' people can probably (if uncomfortably) lie down on the top of a boundary wall, for Beret Guy this may, at various times, mean that he can lie on the vertical surface of any wall (external or internal) that is currently orientated in a fortuitous direction.<br />
<br />
He fell off of the Wall this morning due the Great Attractor being below him during daylight hours and on the horizon during night hours. Because the Day starts earlier in the summer, he fell unexpectedly.<br />
<br />
He gives a short explanation of why The Great Attractor affects him, apparently caused by his bones existing in more dimensions than our normal 3 dimensions of space and 1 of time, and the motion of galaxies, which normally has no significant affect on a person. <br />
<br />
Beret Guy then says that Day-Sliding Season is near, due to The Great Attractor being at the horizon in the Day, and offers to run errands for Cueball in the South, implying that he will be pulled towards the South During Day-Sliding Season. <br />
<br />
Beret Guy is not standing straight up during this comic, he has one knee slightly bent; and walks with a strange gait and movement lines around him. This is presumably due to the extra downwards force that the Great Attractor is currently exerting on him, so he has to exert more effort to hold himself upright. <br />
<br />
The unexpected onset of summer daylight patterns may be further commentary on the ongoing COVID-19 measures and how they have affected perception of time.<br />
<br />
A prior example of an xkcd character with alternate gravitational susceptibility is [[417: The Man Who Fell Sideways]], where a consistent off-vertical pull somehow applies (rather than one linked to a spot on the skies) while other fictional examples of 'personalised' [https://wiki.lspace.org/mediawiki/Tethys gravitational] [https://wiki.lspace.org/mediawiki/Sally_Cambric susceptibilities] also exist, in various forms.<br />
.<br />
<br />
==Transcript==<br />
{{incomplete transcript|Do NOT delete this tag too soon.}}<br />
<br />
:[Cueball and Beret Guy stand next to each other, talking.]<br />
:Cueball: I can't believe it's still light out. It's 8:00 PM!<br />
:Beret Guy: Seriously! This morning I fell off the wall.<br />
<br />
:[In a frameless panel, Cueball and Beret Guy are still standing and talking. Beret Guy is gesturing to the right.]<br />
:Cueball: Wait, why were you sleeping on the wall?<br />
:Beret Guy: The Great Attractor is near the horizon at night right now.<br />
<br />
:[A regular panel, zoomed in on Beret Guy, who is gesturing to the left.]<br />
:Cueball (off screen): The Great Attractor?<br />
:Beret Guy: Yeah! The space one. <br />
:Beret Guy: It pulls on me extra hard. Doctors said it's something to do with galactic motion and how many dimensions my bones have.<br />
<br />
:[Zoomed back out to show Cueball, standing still, and Beret Guy, who is sliding away to the right.]<br />
:Beret Guy: This time of year, it's below us all day, so I stand vertically. But day-sliding season is near!<br />
:Beret Guy: Let me know if you have any errands to run to the south! <br />
:Beret Guy: ''Goodniiighttt''<br />
<br />
{{comic discussion}}<br />
[[Category: Comics featuring Cueball]]<br />
[[Category: Comics featuring Beret Guy]]</div>108.162.237.24