January 2017 News

2016-12-312021-01-04 finished certainty: log importance: 0

This is the Jan­u­ary 2017 edi­tion of the Gw­ern.net newslet­ter; pre­vi­ous, / (). This is a sum­mary of the re­vi­sion-his­tory RSS feed, over­lap­ping with my & ; brought to you by my donors on Pa­treon.






  • , (a de­li­cious time-travel ad­ven­ture, full of Lon­don color draw­ing on Lon­don labour and the Lon­don poor; a cy­clopae­dia of the con­di­tion and earn­ings of those that will work, those that can­not work, and those that will not work, May­hew et al 1851; ul­ti­mate­ly, the el­e­ments don’t come to­gether in as deep a pack­age as and I am a lit­tle dis­ap­pointed that Pow­ers does­n’t pull off nearly as sub­tle a as he does in that—while I hoped that things like the Danc­ing Mon­keys or Ash­b­less were his­tor­i­cally re­al, it turns out that Pow­ers had to make them up. But still a fun reread.

    On a side note: in The Anu­bis Gates, magic is as­so­ci­ated with the and nor­mal­ity with the earth & sun & Chris­tian­i­ty; prac­ti­tion­ers are pained and weak­ened by the touch of the earth and the growth of Chris­tian­i­ty, which pro­tects against & de­stroys magic (and so by the 1800s set­ting, magic has be­come al­most use­less), and grad­u­ally lose weight & float as they grav­i­tate to­wards the moon. The wiz­ened leader of the ma­gi­cians is so many mil­len­nia old and steeped in magic that he would fall to­wards the moon, and must live in a domed build­ing while up­side down lest he fall to the moon like other ma­gi­cians, ro­tat­ing around the dome as the moon moves. Given this Chekhov’s gun, it is not sur­pris­ing that even­tu­ally he does fall out of the dome and falls into the sky, pre­sum­ably to his doom. What hap­pens to him? The char­ac­ter sits around and moves nor­mally while up­side down, and nei­ther bounces nor strug­gles to move; this sug­gests that an equiv­a­lent of Earth grav­ity now pulls him to the moon (or if we as­sume the Earth con­tin­ues to pull, twice Earth grav­i­ty, never mind that the moon is much small­er—this is mag­ic). After falling out of the dome, he will start ac­cel­er­at­ing up­wards at ; as there is air re­sis­tance, he will soon hit , which for a hu­man is ~54m/s, so after ~6s, he will stop ac­cel­er­at­ing and then be­gin ac­cel­er­at­ing slowly as the air thins out & offers less re­sis­tance, in­creas­ing by ~1% every 160 me­ters.

    Log­i­cal­ly, one would ex­pect him to im­pact the Moon at some ex­tra­or­di­nary ve­loc­ity as there will be effec­tively no ter­mi­nal ve­loc­ity for his body once out of the earth’s at­mos­phere, but he of thirst, , or hy­poxia (in in­creas­ing or­der of speed) and prob­a­bly well be­fore he hits the of 19000m. At the Arm­strong lim­it, even the wa­ter on one’s tongue boils. In any case, the ma­gi­cian will be mov­ing so fast that 19000m is triv­ial and will be reached within ~5.8 min­utes, leav­ing lit­tle time for starvation/thirst/hypothermia; by this point, he will have pre­vi­ously lapsed into un­con­scious­ness and be suffer­ing from , yield­ing brain death within 5–10 min­utes. So in gen­er­al, we can safely as­sume that less than 10 min­utes after falling out of the dome, the ma­gi­cian is dead from hy­poxia ac­cel­er­ated by hy­pother­mia. But the body will keep on go­ing. How long does it take to reach the Moon? The moon is on av­er­age 384400000 me­ters away, but the body will keep ac­cel­er­at­ing once it gets past the bulk of the earth’s at­mos­phere; as­sum­ing no more ter­mi­nal ve­loc­ity after 500 sec­onds, the body will reach the av­er­age dis­tance of the moon after ~9351s or ~2.6h, trav­el­ing at some­thing like 86795m/s or 86km/s. (Strictly speak­ing, he might miss the moon and have to spi­ral around, or might even never im­pact, but I can’t cal­cu­late the or­bital me­chan­ics there.) Be­ing a wiz­ened and now desiccated/frozen body, it prob­a­bly does­n’t weigh any­where over 50kg, but will still pack a ma­jor punch with a of 0.2*50*(86795^2) joules or 7.5 mega­joules (for com­par­i­son ).

  • The Com­plete Po­ems, (re­view)