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Talk:2320: Millennium Problems

2020-06-20T21:00:15Z

162.158.106.178: Reflect

Ironically, Randall misspells Perelman as "Perlman" in the comic but spells it correctly in the alt-text.

[[Special:Contributions/172.69.63.147|172.69.63.147]] 02:56, 16 June 2020 (UTC)

:Perhaps he meant Perlman the Perl-programming superhero? ;) [[Special:Contributions/162.158.123.145|162.158.123.145]] 03:33, 16 June 2020 (UTC)
::Or perhaps [https://en.wikipedia.org/wiki/Ron_Perlman Ron Perlman] wrote his own proof on his spare time from acting but never published it? --[[Special:Contributions/108.162.229.234|108.162.229.234]] 13:00, 20 June 2020 (UTC)

:Ironic perhaps, but at whose expense? ;-) --[[Special:Contributions/172.68.215.141|172.68.215.141]] 20:44, 17 June 2020 (UTC)

There has been some controversy over the millennium prizes, given that in mathematics important results are often a product of the work of different mathematicians who are not necessarily close associates. Perelman reportedly believed that his work was a corollary to prior work by Richard S. Hamilton.

I think the idea of this comic is an extension to a question, which I've seen before in this discussion, "what if person A shows that 2 millennium problems are equivalent, and then person B proves one of them?" Should person B get both prizes, or should person A get one of them? It is easy to think of situations where it is hard to know who deserves the credit, and I think this comic takes that
to a logical exteme. [[User:Probably not Douglas Hofstadter|Probably not Douglas Hofstadter]] ([[User talk:Probably not Douglas Hofstadter|talk]]) 03:59, 16 June 2020 (UTC)

The [https://en.wikipedia.org/wiki/Grigori_Perelman Wikipedia article] for Grigori Perelman states the following: "The Clay Institute subsequently used Perelman's prize money to fund the 'Poincaré Chair', a temporary position for young promising mathematicians at the Paris Institut Henri Poincaré.", so no funding would be available for Randall's eighth prize. [[Special:Contributions/162.158.74.61|162.158.74.61]] 04:21, 16 June 2020 (UTC)

By process of elimination, the matrix and the equation should represent Yang-Mills and P=NP, but which is which? The 4x4 matrix could represent the 4D unitary transformation from Yang-Mills? The equation seems to say 'Ar + (squiggles)' but I can't think of any complexity problems that might take this form. --[[User:Quantum7|Quantum7]] ([[User talk:Quantum7|talk]]) 06:35, 16 June 2020 (UTC)

Is "millennium problems" also a pun on "millennial problems", i.e. those issues which seem straightforward to adults but baffle the younger generation (the "millennials")? See for example comic [[2165]]. --[[Special:Contributions/188.114.102.48|188.114.102.48]] 00:48, 17 June 2020 (UTC)

The image is projected by a projector on the ground that Cueball is apparently standing in the way of, but there's no Cueball-shaped shadow on the projected image. {{unsigned ip |108.162.219.192}}
: '''"there's no Cueball-shaped shadow on the projected image."''' - of course not! Cueball is clearly constructed from lines - which (of course) have no width and therefore zero area and as a consequence, cannot obstruct any photons to cause a shadow to form. [[Special:Contributions/172.69.70.213|172.69.70.213]] 02:13, 17 June 2020 (UTC)
::Ha ha. No I think it is easy to see that Randall/Cueball is actually standing to the side of the projectors beam and he is thus not in front of the projector; it is thus not strange that his shadow is not there! --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 09:32, 17 June 2020 (UTC)

It is clearly Randall that makes this presentation based on the caption. Have added this to the explanation and transcript --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 09:32, 17 June 2020 (UTC)

Regarding [https://mobile.twitter.com/johncarlosbaez/status/1271577502947741696], could a professional number theorist please opine on the proof? And for that matter, is Peano arithmetic inconsistency that bad? If so, is it bad on the scale of 2020? I mean, if there are so many things equivalent to Peano arithmetic, then maybe one of them with a very slight change is consistent? [[Special:Contributions/162.158.107.17|162.158.107.17]] 09:55, 17 June 2020 (UTC)
:Imagine the meeting! It would be like if aliens were discovered. "Gentlemen, sooner or later it's going to leak that arithmetic is inconsistent. We need plans. Contingency plans! Get to work!" This could make the CDC zombies site look like a test run. We could have the Count muppet with a thirty minute speech capitulating to veganism. [[Special:Contributions/172.68.189.179|172.68.189.179]] 21:37, 18 June 2020 (UTC)
:In any other year, the inconsistency of arithmetic would cause the collapse of civilization. In 2020, it's keeping it up. [[Special:Contributions/162.158.106.178|162.158.106.178]] 21:00, 20 June 2020 (UTC)

Talk:2321: Low-Background Metal

2020-06-20T08:06:14Z

162.158.106.178: Sweetener

Spoiler Alert for Avengers Endgame next comment [[Special:Contributions/162.158.75.60|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? — [[User:KarMann|KarMann]] ([[User talk: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! [[User:Mathmannix|Mathmannix]] ([[User talk: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. {{w|Scuttling_of_the_German_fleet_at_Scapa_Flow|wikisource}} --[[User:Lupo|Lupo]] ([[User talk: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.)[[Special:Contributions/173.245.54.187|173.245.54.187]] 18:08, 19 June 2020 (UTC)
:The Romans used lead as a sweetener, I think they had plenty. --[[Special:Contributions/162.158.106.178|162.158.106.178]] 08:06, 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?) --[[Special:Contributions/162.158.155.126|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 [[User:ShadwellNH|ShadwellNH]] ([[User talk:ShadwellNH|talk]]) 20:00, 17 June 2020 (UTC) Paul

== 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.
--[[Special:Contributions/188.114.103.129|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? [[Special:Contributions/162.158.158.167|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. --[[Special:Contributions/188.114.102.22|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. [[Special:Contributions/172.69.70.117|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. [[Special:Contributions/141.101.98.130|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? [[Special:Contributions/108.162.216.172|108.162.216.172]] 03:31, 18 June 2020 (UTC)
: Yes. At least it is done with steel. [https://hackaday.com/2017/03/27/low-background-steel-so-hot-right-now/][https://www.good.is/articles/the-search-for-low-background-steel][https://www.stainless-steel-world.net/mobile/webarticles/joanne-mcintyre/disappearing-warships-scavengers-raid-war-graves-for-low-background-steel.html] [[Special:Contributions/172.69.33.129|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. [[Special:Contributions/162.158.123.155|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. --[[Special:Contributions/141.101.105.114|141.101.105.114]] 06:12, 18 June 2020 (UTC)

== May be complicated ==

The 1968 Story [https://scifi.stackexchange.com/questions/109243/modern-military-jet-goes-back-to-world-war-i Hawk among Sparrows] discusses the problems modern war hardware may have when used against old tech. -- [[Special:Contributions/141.101.76.82|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. [[User:Nutster|Nutster]] ([[User talk:Nutster|talk]]) 13:38, 18 June 2020 (UTC)
: {{w|Biggles_(film)|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. [[Special:Contributions/141.101.98.130|141.101.98.130]] 17:11, 18 June 2020 (UTC)
* I am also mildly disappointed that the helicopter is not Airwolf. [[User:Nutster|Nutster]] ([[User talk: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. [[Special:Contributions/141.101.76.82|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. [[User:Cellocgw|Cellocgw]] ([[User talk:Cellocgw|talk]]) 10:05, 19 June 2020 (UTC)

== Add Topic ==

Can we Add Topic with impunity now?
WOOOPEEEE![[Special:Contributions/108.162.216.216|108.162.216.216]] 10:45, 19 June 2020 (UTC)[[Special:Contributions/108.162.216.216|108.162.216.216]] 10:48, 19 June 2020 (UTC)