UmbralRaptor changed the topic of #kspacademia to: https://gist.github.com/pdn4kd/164b9b85435d87afbec0c3a7e69d3e6d | Dogs are cats. Spiders are cat interferometers. | Космизм сегодня! | Document well, for tomorrow you may get mauled by a ネコバス. | <UmbralRaptor> … one of the other grad students just compared me to nomal O_o | <ferram4> I shall beat my problems to death with an engineer.
<Ellied> I do wonder just how chaotic it would be if a pair of bathrooms performed a karyotype on would-be users and had one room for xy, one room for xx, and refused to admit anyone else.
<kmath> <mcnees> Ejnar Hertzsprung born #OTD, 1873 ? ?? ?⚪️ ⚪️⚪️ ⭐️⭐️ ?? ??
<Ellied> AIUI some people would be admitted to one or the other depending on which body part was sampled, some would consistently get the "wrong" one for the gender they present, and some would have it work as most cis people expect
<egg> Ellied: you did see sigfig's second tweet in that thread right
<kmath> <sigfig> two corridors, one with bathrooms for xy and xxy, another with bathrooms for repetitions of x, unlit beyond the second, dark expanse beyond
<SnoopJeDi> Ellied, considering the number of people in the world who are pretty okay with pooping anywhere...
<SnoopJeDi> ¯\_(ツ)_/¯
<Ellied> oh, I found Redox OS today. Super cool project.
<Ellied> Their current live image runs blazin fast in 640x480 on my machine, but unbearably slow at the full 1280x800. I suspect this will improve eventually.
<bofh> Huh, interesting.
<bofh> I wonder why the disparity, are they like doing bitblitting in VESA compatibility mode or something silly like that?
<SnoopJeDi> Ellied, have you encountered NixOS before, btw?
<SnoopJeDi> I'm only vaguely aware of it, but it seems Kinda Interesting™
<SnoopJeDi> definitely not enough for me to try it or anything
<Ellied> SnoopJeDi: I think you've asked me this before, I've read about it but not tried booting it
<SnoopJeDi> oh yes, I probably have
<Ellied> I'm deterred for now by the fact that it still uses systemd, which makes it Not Interesting Enough for the time being.
<Ellied> I'm more interested in throwing in my lot with the likes of Void, stuff that uses experimental minimal init daemons
<Ellied> IME Void has Some Issues but is more than usable as a desktop OS and boots incredibly quickly
<SnoopJeDi> I scanned that line too fast and read "experimental demons" and got rather excited
<SnoopJeDi> SCP OS
* Ellied summons undersecretary RUNIT, DEMON of: -inits -service management
<SnoopJeDi> IäIä SCP-633 > /dev/[redacted]
<kmath> <Dr_ThomasZ> From Earth to space and things beyond, learn about #NASAScience by downloading one of #NASA’s free e-books:… https://t.co/3F49gCxCWL
<SnoopJeDi> <3 Spitzer
<SnoopJeDi> I don't know much of the science out of it, but it's such a good machine. Any machine that gives us space buckyballs is cool by me.
<Ellied> god, picking a desktop environment is just the worst
<SnoopJeDi> computers are hard
<UmbralRaptor> Spitzer does all the things, but it doesn't get Hubble's recognition. Especially in warm phase. =\
<Ellied> it's one of those things where, together, they add up to having everything I want, but no one of them has it all
<SnoopJeDi> ...huh, so I don't think I knew Spitzer was the first one to propose a space telescope.
<SnoopJeDi> Ellied, one of the most frustrating things in tech to be able to conceive what you want as borderline trivial, but it doesn't exist.
<Ellied> oh yeah, a cool thing about redox is just how small the image is. I thought dd was breaking and stopping early, but no, it really is 38 megabytes.
<SnoopJeDi> I reckon that's why the philosophy that should fix problems you care about exists. So much progress is "man, this *sucks*, I'm fixing this problem"
<Ellied> SnoopJeDi: indeed
<bofh> ^
<UmbralRaptor> It's frustrating how many problems seem to fall into "spend a bunch of money, or do without," though.
<Ellied> gaaaah I keep googling for stuff about computer-to-computer transfer of data with USB 3.X, which I understand is in the spec, and expecting to find people who understand what they're talking about in any way.
<Ellied> (I am not finding any such people.)
<Ellied> It's just the same damn canned answer about how USB is strictly host-to-peripheral which is only true of 2.0 and earlier
<bofh> SnoopJeDi: unrelated but this is still the best SCP: http://www.scp-wiki.net/scp-1281 (read Interview Log #4)
<Qboid> [#4] title: Porting geometry to c++ | | https://github.com/mockingbirdnest/principia/issues/4
<Ellied> "Can I do this?" "No, USB is strictly host-to-peripheral" "ok but I said in my question that I meant 3.0, I think the standard describes this" - what comes next is either "oh well I don't know then so I guess no one supports it" or some complete bullshit about power transfer.
<bofh> thank, Qboid. Thuboid.
<egg> bofh: :D
<bofh> Ellied: so I'm fully willing to believe it's 100% unsupported, tbh.
<bofh> like this is genuinely the first I've heard of that capability.
<Ellied> yeah, I think that must be the case
<Ellied> dammit, I thought USB was finally catching up to RS-232 in that respect.
<Ellied> you can buy crossover cables on amazon even
<bofh> so like that's a thing with RS-232 b/c there's no distinction between host and peripheral.
<Ellied> sure there is, what about DTE and DCE?
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<Ellied> What I can find in the way of docs suggests that crossover cables are supposed to be a special case, but judging by the equipment we have it at least became the norm at some point
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<Ellied> we have like 2 DTE-to-DCE non-crossover cables in my department and a great many crossovers, and all the machines have a DTE connector.
<bofh> okay, sure, if you're doing h/w flow control. but, um, why bother?
<SnoopJeDi> bofh, is this obliquely referencing a real SC?
<bofh> SnoopJeDi: I genuinely don't know, it *might*.
<SnoopJeDi> OH
<SnoopJeDi> I didn't realize I had to click
<SnoopJeDi> reading the interviews now, ta
<SnoopJeDi> bofh, oh my god.
<Ellied> I guess I don't know why you can't just open a USB port as a virtual terminal and send/recv data asynchronously now that 3.0 brings in dedicated TX/RX lines.
<Ellied> I get that before, the interface was strictly half-duplex so you had to conform to more restrictive standards about who can talk when
<bofh> Ellied: wait, it does?
<bofh> what the fuck, USB3 *isn't* half-duplex?
<Ellied> uh, I think? It's supposed to at have a full-duplex mode at least
<bofh> did someone have a sudden attack of sanity?!?
<Ellied> like, the bitrate listings all have full-duplex and half-duplex mode. In fact, I think half-duplex mode might be a 3.1 feature that's not present in 3.0, which is strictly full, but I might misremember.
<Ellied> From Wikipedia: "USB 3.0 has transmission speeds of up to 5 Gbit/s, which is about ten times faster than USB 2.0 (480 Mbit/s) even before taking into account the fact that USB 3.0 is full duplex whereas USB 2.0 is half duplex."
<bofh> what the hell, who suddenly decided to be sane and make USB3 not half-duplex?
<bofh> SnoopJeDi: yeah that's my reaction too.
<Ellied> I think 3.1 uses some kind of magic to assign data lanes depending on how the connector is plugged in anyway (there are four differential pairs that can ideally be used independently, so the connector's not truly symmetric) so presumably that mechanism also brings in half-duplex capability while 3.0 just has preassigned RX/TX
<Ellied> that doesn't actually make sense, you could just have one pair of opposite corners be TX and the other pair RX and never have to switch them
<Ellied> IAC I do know that 3.1 has a 10 Gbps mode that I think must be half-duplex.
<UmbralRaptor> SnoopJeDi, bofh: ow. That SCP hit me in the feels.
<SnoopJeDi> YES
<SnoopJeDi> A BIT
<SnoopJeDi> particularly considering having just finished Liu Cixin
<SnoopJeDi> well, finished the 3BP trilogy*
<bofh> Nice! Tho my thoughts on the third book in that trilogy are... complicated. (As in I genuinely am not fully sure what I think of it).
<SnoopJeDi> I like the complication the books gave me, but I think we're about on the same page there
<SnoopJeDi> Which at this point surprises me $0% because we seem to sync up on quite a few things :D
<SnoopJeDi> bofh, I'm very game to hear those thoughts sometime somewhere less likely to spoil things :)
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<kmath> <plutokiller> Ah, here's what I'm mad about. While I was gone Diane got to witness the bobcat - house cat meeting and I missed it… https://t.co/WDRjyEiDud
<bofh> SnoopJeDi: sure, let me organize them a bit more first, since they're fairly incoherent atm.
<bofh> and yeah we do seem to have similar opinions and thoughts on a bunch of things. it's nice :D
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<kmath> <diodelass> Hardware store: ASK US ABOUT THE BURMESE PYTHON *BEFORE* CHECKING OUT
<UmbralRaptor> That's one way to stop shoplifting.
<SnoopJeDi> bofh, no rush, just wanted to float it out there. I have some thoughts on each written up on GoodReads, but they're very careful about giving anything away
<SnoopJeDi> because it's such a fun ride
<bofh> oh, link to your GoodReads? also should set one up myself, been meaning to for *so* long.
<SnoopJeDi> my shelves are a mess, but I've tried to write a review of some sort for almost every book I've finished in the last year or so
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<kmath> <glsfrg> 国際輸送(世界のほど全ての国を除く) https://t.co/hCXAOmiT4L
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<kmath> <FioraAeterna> https://t.co/w1t3EVAfgC
egg is now known as egg|afk|egg
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<egg|work|egg> !kd next
<Qboid> egg|work|egg: Sequence contains no elements
<egg|work|egg> hm
<egg|work|egg> !wpn whitequark
* Qboid gives whitequark a Laplacian
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<whitequark> !wpn egg
* Qboid gives egg a chi physicist
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<kmath> <Bodegacats_> https://t.co/2Y1qbYZe55
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<bofh> !wpn egg
* Qboid gives egg a sarcastic set
<bofh> !wpn whitequark
* Qboid gives whitequark a Лифшиц neutronium reactor
<bofh> SnoopJeDi: thanks
<egg|work|egg> !wpn bofh
* Qboid gives bofh a discrete homomorphism
<kmath> <IBJIYONGI> Ok this is just weird. https://t.co/mMrHUJJui2
<UmbralRaptor> o_O
<UmbralRaptor> bofh: https://photos.app.goo.gl/CCYssZuNWa9bQJh32 still looks like one of those parody "I hate Physics" problems.
<APlayer> Hi!
<bofh> UmbralRaptor: OH GODS IT REALLY DOES
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<bofh> https://mobile.twitter.com/bofh453/status/905497174791909377 I *really* hate how this post is fucking evergreen.
<kmath> <bofh453> Current mood: <@Newpa_Hasai> Is 2017 the series finale or something? <@jgerity> If it's not we're definitely poised mid-air over the shark.
<UmbralRaptor> AAAAAAAAAAAA
<APlayer> Hi!
* SnoopJeDi misread "the spectre of bread" as "the spectrum of bread"
* SnoopJeDi sips more coffee
* APlayer gives SnoopJeDi sleep pills
<SnoopJeDi> legitimately been considering them
<SnoopJeDi> but can't come to any conclusion other than "I'm being lazy about sleep hygiene"
<APlayer> Heh
<bofh> SnoopJeDi: so the spectrum of bread sounds honestly more interesting.
<bofh> 13C NMR, preferably
<SnoopJeDi> I'd be willing to bet you could do legitimate process QA with Raman
<SnoopJeDi> you can do it with chocolate, after all
<bofh> Oh, I'm pretty sure that's already done to some extent.
<SnoopJeDi> for chocolate, or bread?
<bofh> Both, actually. I know it's a thing with chocolate tho.
<bofh> Also sec, that reminded me of one of my favourite papers ever.
<SnoopJeDi> ooh, if you have a ref for the bread thing, I'd *love* to send that to a colleague who bakes a lot
<SnoopJeDi> (he owns a copy of Bread, Tartine Bread, and a few others, and has followed quite a lot of them)
<bofh> http://www.sciencedirect.com.sci-hub.cc/science/article/pii/S0260877405002839 "Dielectric properties of processed cheese from 0.3 to 3 GHz"
<SnoopJeDi> and then I'm over here like "King Arthur 30 min baguette recipe? sold."
<SnoopJeDi> Journal of Food Engineering
<SnoopJeDi> oh my god
<bofh> Will take a look, that would be interesting. Also 30min baguette recipie? Damn.
<SnoopJeDi> I've...never actually *wanted* to follow a journal so much
<SnoopJeDi> bofh, to call them baguettes is rather disingenous, but it's a nice recipe for some quick dinner bread www.babble.com/best-recipes/crusty-baguettes-made-fresh-in-30-minutes/
<SnoopJeDi> (the mechanics hydration in crust formation are *fascinating*)
<SnoopJeDi> of hydration*
<bofh> Well okay sure, but my palate is hardly what one could call "discerning" :P
<SnoopJeDi> as a former fat guy, I'll eat generally anything lmao
<bofh> Same (I think the only reason I haven't gotten fat is a combo of fast metabolism and the fact that I used to often forget to eat a lot).
<SnoopJeDi> I'm super relieved that IF is...kind of the default thing we're adapted to.
<SnoopJeDi> I feel a lot better about "well sometimes I eat a lot and sometimes I forget food exists"
<bofh> Yeah, heh. When I read about IF the first time I was like "welp okay maybe my eating habits aren't totally fuckawful".
<bofh> Also yeah, now that you mention it, crust formation *does* strike me as complex, I mean it's basically fluid dynamics meets convective heat transer.
<bofh> transfer*
<SnoopJeDi> yea, the presence of steam is highly nontrivial
<SnoopJeDi> also oven spring is *amazing*, I did not realize until very recently that it was dominated by yeast activity because it's an O(10 min) process and that just seems so fast for yeasties
<UmbralRaptor> IF?
<SnoopJeDi> intermittent fasting
<UmbralRaptor> Ah.
<SnoopJeDi> eating to a schedule is a remarkably modern societal invention
<bofh> OH GODS THAT CRACKPOT EMAIL.
<SnoopJeDi> it's so good I'm not even angry
<SnoopJeDi> it's years old but I keep it as my favorite
<SnoopJeDi> went into my google drive to find a pic of the SSC dipole and found that too
<bofh> reminds me of quantum_physics_.doc, which is my fav
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<SnoopJeDi> also yea speaking of time machines...have that too: https://i.imgur.com/YEYRlaA.jpg
<SnoopJeDi> I used to walk past that equipment daily (it's since been moved), it was like walking to work over your predecessor's rotting corpse
<SnoopJeDi> TIL antiword
<SnoopJeDi> We don't get much loonie spam anymore because we're on gmail. Every now and then "Higgs was Xenon! Nobel is a fraud conspiracy!" gets through
<bofh> interaction in the quantum theory of a field - result of an
<bofh> exchange in quanta of a field ». Extremely vaguely. To understand it is
<bofh> impossible. I.e. they naming space empty, vacuum, there and then say,
<bofh> that there is weeding, there are» fields of particles », there an
<bofh> exchange in" field quanta »! Whether this slyness? Whether it is
<bofh> falsity? And who, at last, from all cohort of physicists of the world
<bofh> will explain, what such"field"? The paradox turns out: the field is, and
<bofh> its material carriers do not exist! I.e. the field exists out of the
<bofh> carrier, without the carrier?! That's it in it, in this open and
<bofh> unattractive slyness an essence modern, and in many respects corrupt
<bofh> physics. Today there is no physical sense and logic. Today is physics
<bofh> any more paradoxes, and the physicist of absurdities.
<bofh> oops, wrong paragraph
<bofh> And on the
<bofh> earth areas are known, in particular in Crimea, where there is an
<bofh> antigravitation and cars get uphill without engine. Here there, in
<bofh> depth, fastest, these moments, this orientation of nucleus, has a
<bofh> direction opposite to "regular". It is necessary to measure simply there
<bofh> these polarized waves of gravitation, but, on what frequencies?
<bofh> it's just pages & pages of this sort of drivel.
<SnoopJeDi> "cars get uphill without engine"
<SnoopJeDi> a-are we just gonna drive right past that, as it were
<SnoopJeDi> THIS SEEMS WORTH EXPOUNDING UPON
<bofh> there are so, SO many random asides like that
<SnoopJeDi> I really *really* wish I had bookmarked it, but I read a great article last year about someone who tutored cranks on Skype
<SnoopJeDi> and it perfectly summarized why I find them to be of legitimate academic interest
<bofh> We too can count up approximate structure of a person soul, as sets of
<bofh> these elementary data carriers, but already using own image of
<bofh> Planck’s elementary quanta. The weight of of a person soul is ca. 20
<bofh> gramme.
<SnoopJeDi> inasmuch as questions are Our Thing™ and investigating those questions all on their own is valuable
* SnoopJeDi is pretty ignorant of epistemology but hugs it
<bofh> sec
<SnoopJeDi> omg yes, thank you
<SnoopJeDi> you are a good external brain bofh
<bofh> np
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<SnoopJeDi> oh huh, FTIR is apparently common for bread, too
<SnoopJeDi> I mean I'm not shocked, but FTIR seems like such a blunt instrument to me in my ignorance of it
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<bofh> To be honest, same.
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<egg|afk|egg> bofh: hmm, I think I remember seeing "Dielectric properties of processed cheese from 0.3 to 3 GHz" somewhere...
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<egg|afk|egg> UmbralRaptor: cat!!!
<UmbralRaptor> egg|afk|egg: sad possibly partially blind and stiffly walking cat. =*
<UmbralRaptor> s/*/(/
<egg|afk|egg> ow
<UmbralRaptor> Same cat as before.
<egg|afk|egg> UmbralRaptor: have you tried interacting with that cat?
<UmbralRaptor> egg|afk|egg: Yes. It wouldn't let me near.
<egg|afk|egg> hm
<egg|afk|egg> !wpn Fiora
* Qboid gives Fiora a numerical mass-driver
<APlayer> Hi!
<egg|afk|egg> !wpn UmbralRaptor
* Qboid gives UmbralRaptor a planar McBoatFace
<egg|afk|egg> !wpn bofh
* Qboid gives bofh an ultraviolet Kerbal
<UmbralRaptor> !wpn egg|afk|egg
* Qboid gives egg|afk|egg a BS 6008 épée
<UmbralRaptor> !wpn APlayer
* Qboid gives APlayer an ovoid homomorphism
<UmbralRaptor> !wpn -add:adj ultraviolent
<Qboid> UmbralRaptor: Adjective added!
<APlayer> !wpn UmbralRaptor
* Qboid gives UmbralRaptor a rho ㎭
<APlayer> UmbralRaptor: In that case, there should be "infrabred"
<kmath> <purpledocket> ok no stop everything these are apparently called WILD SAND CAT KITTENS and no one had ever filmed them irl before https://t.co/FGU5z3aZU6
<Iskierka> I am certain I have been video of such fluffs before
<APlayer> "Senior Social Food Video Correspondent"
<egg|afk|egg> !wpn whitequark, котя, and порошок
* Qboid gives whitequark, котя, and порошок an unamused dubious point
<APlayer> Hi egg!
<kmath> <illegalhex> Harry Potter is a story of a white boy who is told he is very special, gets into a prestigious public school becaus… https://t.co/rJZ77XVpaT
<APlayer> Did you see my question from yesterday?
<egg|afk|egg> what was it?
<UmbralRaptor> …public?
<Iskierka> that length limit becomes silly now with 280
<Iskierka> yes, public
<APlayer> http://www.aerospacengineering.net/?p=1598 at equation (5.37), what do you think is the vector r? It may or may not be the current position, but I doubt it is, for by changing the position, I believe the departure angle would change as well
<Iskierka> they are public in that any member of the public can technically join
<UmbralRaptor> But not publicly funded?
<APlayer> Wait, how are schools in the US funded?
<HebaruSan> Local property taxes pay for a spot for each student in by law, run by local school districts. But each family can opt out and pay separately to send their child to a "private school".
<APlayer> Well, then. Pretty similar to how German schools work
<Iskierka> UmbralRaptor, no, or at least not to any major extent (it's possible there may be grants for building development or such). They came before a public school system so a public school is separate to a public-sector school
<UmbralRaptor> hrm
<kmath> <diodebot> reverse blocking anti-boiled-egg bobcat-conducting pentalayer diode
<APlayer> Physics at your service: https://imgur.com/gallery/tLtCq
<UmbralRaptor> o_O
* egg|afk|egg pets UmbralRaptor with a cat
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<UmbralRaptor> meow?
<kmath> <janmpdx> What's wrong, Dr. Schrödinger? Were you expecting a cat? https://t.co/vRdN11fWlG
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<UmbralRaptor> Does this count a a refrigerated room? https://photos.app.goo.gl/Zu4aYvAUyjC8GYBG3
<UmbralRaptor> egg|afk|egg, whitequark: https://twitter.com/PhotoandGrime/status/917827377455091713
<kmath> <PhotoandGrime> "Can you eat fried moth?" - Culinary questions in a Dutch children's book. https://t.co/bXgmwwvSqj
<UmbralRaptor> o_O
<rqou> argh egg|afk|egg i need homework help again again
* rqou is drowning in a sea of problem sets because my time management sucks
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<egg|afk|egg> moo?
<SnoopJeDi> rqou, big fan of the pomodoro technique at the moment, although it's...of questionable success for me.
<rqou> how do i even start on problem 1?
<rqou> i hate delta-epsilon proofs
<rqou> intuition says the answer is T*epsilon_1*(epsilon_0)
<SnoopJeDi> ugh the way that's written (x(t) vs z(t)) frustrates me
* egg|afk|egg glares at the date format
<rqou> yes, it's 'murican
<SnoopJeDi> all calendars are bad egg|afk|egg
<egg|afk|egg> julian date ftw
<rqou> btw this is due in an hour
<rqou> i did the other problems already
<rqou> hopefully they're correct :P
* egg|afk|egg stabs the postfix quantifier
<SnoopJeDi> rqou, this is outside my recollection but have you already begun by writing (xdot-zdot)=(x-z)dot and integrating?
<rqou> how does that help?
<SnoopJeDi> inasmuch as the integral of d(x-z) is (x-z)
<rqou> so my intuition is that since the change in the derivative is bounded by epsilon_1, then over T amount of time the output should deviate by no more than T*epsilon_1. and then the initial condition deviates by epsilon_0, so multiply all of these together i guess??? and get a bound
<rqou> but idk if this is correct or not
<egg|afk|egg> SnoopJeDi's approach sounds sane?
<SnoopJeDi> I think that's the best mathematical compliment I've ever gotten egg|afk|egg :P
<rqou> wait, that is just T*epsilon_1
<egg|afk|egg> you end up with sum of f from t0 to t = (x-z)(t)-(x-z)(t0) = (x-z)(t) - δx0
<egg|afk|egg> the left hand side thereof being bounded by sum of ε1 from t0 to t = ε1(t-t0), so T ε1 + δx0 >= ε1(t-t0) + δx0 >= (x-z)(t)
<rqou> hmm, so i don't need to multiply epsilon_1 and epsilon_0?
<egg|afk|egg> (where t in the above ranges between t0 and t0 + T, and T is positive)
<rqou> so your bound is tighter
<rqou> whatever, turning it in :P
<egg|afk|egg> rqou: why do you want to multiply them?
<egg|afk|egg> how does that make sense?
<rqou> mumble mumble idk
<SnoopJeDi> it's usually most straightforward to try the "obvious" thing and then start cheating with analysis when you hit walls
<SnoopJeDi> so "I wanna bound [thing]" starts with the thing
<rqou> wait, f(t) is added to the derivative, zdot
<rqou> not z
<egg|afk|egg> rqou: so like what's the calculation that yields their multiplication? you're not supposed to just produce a salad of the symbols in the question :-p
<SnoopJeDi> you have a bound on f(t) though rqou
<SnoopJeDi> (which bounds its integral)
<rqou> hmm but intuitively adding them doesn't seem quite right
<SnoopJeDi> egg|afk|egg, alas, symbol salad is the rule rather than the exception in American maths :(
<rqou> if the derivative changes a lot, then a smaller change in the initial condition causes a larger change in the output
<SnoopJeDi> if you're one of the lucky ones who intuits something about the properties of the symbol-pushing you do in your formative years, you spend another bunch of years undoing the damage...
<rqou> e.g. intuitively if epsilon_0 on the initial condition is e.g. 1
<egg|afk|egg> 1 what
<SnoopJeDi> rqou, right, that same logic lets you say \int_t0^{t0+T){f(t)} <= T*ε1
<egg|afk|egg> you don't need those things to live in a field
<rqou> hmm now i've confused myself
<egg|afk|egg> plonk them in a vector space, e.g. say x is a length
<egg|afk|egg> (and t a time, let's not go too nuts)
<rqou> but there's still the intuition that the change in the derivative should scale the change in the initial condition
<rqou> not just be added
<egg|afk|egg> f(t) is then a speed, bounded by ε1 (a speed, too), ε0 bounds a difference in x and is a length
<rqou> aaah i see
<egg|afk|egg> rqou: why
<rqou> it's a speed
<rqou> not an acceleration
<SnoopJeDi> right, you bound the "speed" (f) so you bound how far you could possible have gone
<rqou> too many dots everywhere
<rqou> so yes, it seems T*epsilon_1 + epsilon_0 should be sufficient
<rqou> the reason i've confused myself is that the standard solution has a huge time-varying "state transition matrix" Phi
<rqou> which is multiplied
<rqou> so i was thinking "what happened to this multiply operation"
<egg|afk|egg> the change in the initial condition is just me nudging you, which has no effect on anything (I just declared the origin to be 5 metres further over there)
<rqou> er, this system isn't LTI though
<egg|afk|egg> it's kept (the origin is still there after T), but it doesn't get amplified or anything
<rqou> but wait
<egg|afk|egg> you getting an additional time-dependent speed f(t), otoh, does change things
<egg|afk|egg> albeit at most in proportion of the supremum of f and of T
<SnoopJeDi> unrelated, this is a nice viz: https://bl.ocks.org/gcalmettes/c3363abb74fe219b283782f055b72386 (cc bofh)
<rqou> couldn't getting a new initial condition move you from a "moves normally" part of the state space to a "flings you to a bajillion instantly" part of the state space?
<rqou> because this isn't necessarily LTI
<egg|afk|egg> SnoopJeDi: did I mention that my mission statement at work is "Positive Ляпунов exponent"
<egg|afk|egg> rqou: what do you mean by LTI?
<rqou> linear time invariant
<egg|afk|egg> what does that mean
<SnoopJeDi> I'm not familiar egg|afk|egg (I'm the fabled impostor!)
<egg|afk|egg> rqou: oh, p depends on z, hm
<rqou> yeah
<egg|afk|egg> yeah then it's trickier,
<egg|afk|egg> blarg
<rqou> so you could have a p that is "if less than 1 then a small negative number, else it's a bajillion"
<rqou> then if you're at 0.99 you eventually go to 0
<rqou> but if you're at 1.01 then you end up at a bajillion instantly
<egg|afk|egg> yeah yeah, the proof above was incorrct, because x'-z' is not f
<egg|afk|egg> you should have yelled at me
<rqou> i was thinking that wasn't quite right
<egg|afk|egg> (it's not -f rather)
<rqou> but now i realize T*epsilon_1*epsilon_0 isn't right either
<egg|afk|egg> no that literally makes no sense (try putting some units on it, it's a surface!?
<egg|afk|egg> )
<rqou> yeah hmm
<egg|afk|egg> blarg, do some series expansion on p? how smooth is p
<rqou> hmm, now i think the answer is maybe T*epsilon_1*(*mumble* *mumble* something about Lipschitz bound on p)+epsilon_0
<egg|afk|egg> well you certainly need a + ε0 somewhere
<rqou> no, that can't be right either
<egg|afk|egg> if ε1 = 0, you still get your ε0
<rqou> how about (*mumble* *mumble* something about Lipschitz bound on p)*(T*epsilon_1+epsilon_0)
<rqou> :P
<rqou> that intuitively seems to work
<egg|afk|egg> maybe? I don't know, try doing a proper series expansion on p
<egg|afk|egg> what is meant by "obeys the conditions of the fundamental theorem"
<egg|afk|egg> which fundamental theorem :-p
<rqou> p is Lipschitz continuous
<SnoopJeDi> I think it's a very sloppy way to say "you can integrate this thing"
<egg|afk|egg> SnoopJeDi: well if it's Lipschitz continuous it's a hell of a lot more than "you can integrate it", even Riemann
<SnoopJeDi> you're not wrong but I don't have access to magical information egg|afk|egg
<SnoopJeDi> "fundamental theorem" in such a context rings like FTC -> go nuts with integration in your problem-set
<rqou> er, to clarify
<egg|afk|egg> rqou: ok, so the Lipschitzkonstante will appear with some mumbling; do the calculation and it should be fairly clear :-p
<rqou> p is lipschitz continuous in x and piecewise continuous in t
<rqou> so the solution to the differential equation exists and is unique
<egg|afk|egg> "fundamental" you keep using this word, I do not think it means what you think it means
<SnoopJeDi> gotcha, you have the integrability you need for the time bits, then
<rqou> it's fundamental for this course at least
<rqou> which is on linear systems
<egg|afk|egg> yeah :-p
<SnoopJeDi> A bit too practical for mathematician-type pathologies? ;P
<rqou> at least overall this course is much better than the robotics course and probably less stabbity-inducing
<egg|afk|egg> stabbity!
<egg|afk|egg> UmbralRaptor: Iskierka: the formerly confused kitty is happy https://forum.kerbalspaceprogram.com/index.php?/topic/162200--/&page=33&tab=comments#comment-3191363
<rqou> gah i have no idea how to prove this
<rqou> f*ck it OutOfTimeException
<SnoopJeDi> dd if=/dev/panic of=life.exe
<egg|afk|egg> ferram4: so we don't want to block the moon on a FAR release, so while Chasles has everything in place to manage vessels in the atmosphere, it will only manage to the ground when there's no atmosphere, and stop at the border of the ferram4 sector otherwise https://github.com/mockingbirdnest/Principia/wiki/Change-Log#chasles
<egg|afk|egg> ferram4: once the next release of FAR comes out we can enable it inside the atmosphere
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<egg|afk|egg> !wpn -add:wpn kitten
<Qboid> egg|afk|egg: Weapon already added!
<egg|afk|egg> !wpn UmbralRaptor
* Qboid gives UmbralRaptor a sparse vertical (with ground plane)
<SnoopJeDi> egg|afk|egg, oh lmao I'd misread your first message anyway. That's an amazing short summary.
<SnoopJeDi> Would make a good conference badge subtitle
<egg|afk|egg> SnoopJeDi: context: my tech lead has "actively reduce chaos" and the local admin has "embracing chaos", so I felt I should have something chaotic as a mission statement too :-p
<SnoopJeDi> chaotic eggcellence
<Iskierka> apparently I need to go watch the GDQ clustertrucks run
<Iskierka> as the developers logged into the game and started fucking with dev settings
<SnoopJeDi> lmao really?
<SnoopJeDi> I missed that one but the game looks fun
<Iskierka> I'm watching them do it to nerdcubed right now (though vod, not live) and the chat said that happened
<Iskierka> "It's very rare when playing a game that you start getting molested by your fans, then attacked by the developers"
<Iskierka> currently all the trucks are luminous green
<Iskierka> only they're preposterously luminous
<Iskierka> like one is washing out the entire level
<ferram4> egg|afk|egg, this works.
<SnoopJeDi> I'm kinda concerned they can change params in the middle of a game so readily, Iskierka?
<Iskierka> It sounds like they do it via the twitch integration with special devname-activated commands, so you know who's doing it and when
<SnoopJeDi> THIS IS NOT HELPING MY LEVEL OF CONCERN
<Iskierka> I mean arguably the normal twitch integration screws with the game more :p
<Iskierka> turn on earthquakes, laser trucks, exploding trucks, changed gravity
<SnoopJeDi> hmm, that's a good point, I guess I'm overreacting with knee-jerk "hooking things up to the internet is aaaaAAAAA"
<Iskierka> I don't think there's any feed-out other than your active choice to stream it, and not sure what it could really capture anyway. It seems to just be reading "let's see how silly we can make the game go in a popular stream"
<Iskierka> now they doubled physics speed
<SnoopJeDi> pretty good kek-mine to mess with a GDQ run
<Iskierka> If it does require twitch integration I suspect they weren't being super-serious to begin with, but it's certainly entertaining :p
<Iskierka> https://go.twitch.tv/videos/181016673 less srs than GDQ, but this is the N3 one and I think they start showing up at around 1:10-1:15
<Iskierka> https://youtu.be/wB7xRFTlahU GDQ compilation, seems much tamer
<kmath> YouTube - Landfall games "hacks" SGDQ 2017 (Clustertruck)
<kmath> <scanlime> I love to share with the little tiger https://t.co/Rmb2tmfTCQ
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<egg|afk|egg> Iskierka: huh, neat
<SnoopJeDi> I like movement-based games
<SnoopJeDi> Speedrunners is an evergreen couch game for me
<egg|afk|egg> Iskierka: wow those green trucks are bright
<bofh> "couch game"?
<SnoopJeDi> friends sittin on the couch playing something or other
<SnoopJeDi> don't do that nearly as much as I'd like to, but the folks I do it with all play that at roughly the same skill level so it's like Mario Kart but fun
<egg|afk|egg> !wpn bofh
* Qboid gives bofh an IEEE 754 wombat
<Ellied> !g IEEE 754
* egg|afk|egg takes the square root of the wombat
* egg|afk|egg takes the nth root of the wombat for n=2
<Ellied> oh, floating point arithmetic
<egg|afk|egg> the results have different sign bits
<Ellied> wait what
<Ellied> how does that work
<egg|afk|egg> ask the cat?
<egg|afk|egg> (or bofh and Fiora but iirc we're all confused by that particular one here)
<Ellied> whitequark: can you ask your cat about that one for me?
<egg|afk|egg> oh I didn't know котя did numerics too
<Ellied> you said to ask the cat, which one did you mean?
<whitequark> what
<Ellied> I don't have a cat to ask here
<egg|afk|egg> I meant Atlas
<Ellied> oh
<kmath> <stephentyrone> @apontious https://t.co/O6ZE8RY65H
<Ellied> kitty!
<egg|afk|egg> whitequark: context: sqrt(-0) and rootn(-0, 2) are not the same in IEEE 754-2008 (and sqrt(-0) seems to make little sense as far as bofh and I can tell)
<egg|afk|egg> whitequark: have you taught котя about floating-point arithmetic yet,
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<whitequark> heh
* UmbralRaptor performs a Legendre transformation on egg|afk|egg.
<kmath> <worddroppings> Sometimes I meet a phlebotomist that I want to kidnap and keep for my own personal use, the keeper of my veins?