The Restaurant at the End of the Universe

Marvin

00:43

0

Q: Is there an upper height limit to magical flight in Harry Potter?

In the beginning of Harry Potter and the Deathly Hallows, Harry Potter needs to get from point A to point B as quickly as possible without being intercepted by enemies. Knowing that there is a magical trace (apparently unbreakable) always in effect on Harry Potter until he turns 17 (so running in...

Alex

01:12

Is there usually a time delay between a flag or close vote and arrival in the review queue?

DavidW

01:47

@Alex Yes. Someone like Carrot would probably have a fair idea of the actual number of minutes, but it's usually long enough for obvious stuff to collect 5 votes before it gets to the queue. Probably min. 10 minutes just at a guess.

Marvin

04:02

2

Q: Book where the main character gets stuck in a VR world after going onstage to play it

The part I remember was when the main character goes into a big hall I think, where a game is getting released. And because of some other reasons I cannot remember he gets called onto stage to play it. It's like a VR game and he sort of gets stuck in it, with a few other people. And he has to sur...

story-identification books

Mithical

04:56

@Marvin This is a very common trope, and I don't think there's enough information here to uniquely identity something.

DavidW

05:10

The detail of a release-day stage presentation may narrow it down just enough to make it answerable. At least it makes it not a match for any books listed on TVTropes "Inside a Computer System" page.

Jenayah

05:29

@Randal'Thor thanks for the tip!

Marvin

05:41

0

Q: Children's book (possibly duology) about cloned boys

What I remember: Published no later than 1990, probably more like 1985 Near future setting, possibly featuring a vague Eastern/Western cold war scenario A boy of ~10 learns that he has a clone of the same age The clones secretly work together to ... do something that foils the plans of the adult...

story-identification childrens-novel clones

Jenayah

06:32

Daily floof, 2021/06/03: is that because of the vaccine?

3

Marvin

07:45

0

Q: Manga wherein the main character gets a wolf tail

I don't recall much about it, but I remembered reading a manga wherein the main character is a high school guy who somehow ends up getting a wolf's tail. Furthermore, his male friend also ends up with an animal characteristic, namely bird wings, and became a villain for a few chapters. And that's...

story-identification manga

TheLethalCarrot

08:04

@Alex Close votes always take a minimum of 15 mins. IIRC LQPs show up at least 15 mins later if the post is <15 mins old or at the next review script run so ~5 mins if the post is >=15 mins old on the first flag

This is all based on experience and the queues aren't as predictable as they were a while back so it might not be 100% accurate

Mithical

08:32

@Marvin self answered in an edit

TheLethalCarrot

Unless I'm the one mis-remembering that some of those details don't sound right at all

Rand al'Thor

@Lpgfmk Welcome to chat! :-)

TheLethalCarrot

@Mithical Are you going to answer that so we have a trail of it because the edit should really be rolled back?

Mithical

08:52

Don't have the time, feel free to

TheLethalCarrot

Okay, I'll do a community wiki answer for it

Can't remember if this book in the series is on topic actually

Oh I suppose the game tech is actually

Lpgfmk

@Randal'Thor aaaahahaha @Randal'Thor just welcomed me! WOT fans unite! I have no idea where this is though.

Rand al'Thor

:-D

Chat is like the informal part of Stack Exchange: you've got the main site for Q&A, the meta site for Q&A about the site, then chatrooms for just hanging out and talking.

I guess you joined this room via a link from somewhere. As it says in the room description:

> General discussion for scifi.stackexchange.com, both on-topic and off-topic. Engage at the risk of your own sanity, but please be nice and don't panic.

b_jonas

09:09

Whoa, a gold publicist badge?

I got a gold publicist badge for scifi.stackexchange.com/q/76205/4918 . Let me see what happened.

Unclear. My comment scifi.stackexchange.com/questions/15335/… leads there, but I don't see why that question got popular. Maybe it's just accumulated views over years, but still.

Feeds

09:25

Darths & Droids: Episode 2004: Oi, Kanata! We Scanned a Bar for Thee

posted on June 03, 2021

b_jonas

09:56

18

Q: Would a lightsaber cut through wood?

Usually we see lightsabers cutting through metals like butter, with a few notable exceptions. And we know it can cut through flesh while cauterizing the wound. But what about material with a different resistance to heat, like a wet log? Could a lightsaber cut a tree down with a slice or by just t...

star-wars lightsaber

^ Is OP trying to somehow confuse Star Wars with Doctor Who?

AncientSwordRage

@b_jonas you can give other people those badges if you use their user ID

@b_jonas I don't think so

TheLethalCarrot

@AncientSwordRage Several of my Announcer badges came to me this way

I think you can work out which ones

Ugh can you not remove tab hover cards anymore in Chrome?

AncientSwordRage

@TheLethalCarrot hover cards?

@TheLethalCarrot hmm...

TheLethalCarrot

howtogeek.com/446271/…

AncientSwordRage

@TheLethalCarrot I hadn't even noticed they were a thing

my current battle is Chrome Tab Grid on mobile

TheLethalCarrot

10:11

Yeah looks like the removed the ability to disable the feature and actually made it worse, in my opinion, by adding tab hover card images. At least you can disable that though

AncientSwordRage

for now

TheLethalCarrot

Yeah, if that feature becomes a permanent none removable thing I might ditch Chrome

b_jonas

@AncientSwordRage I know

AncientSwordRage

@b_jonas I'm suggesting that might be what happened

b_jonas

I don't think so.

TheLethalCarrot

10:17

The question that comment is on has 132k views and that might not be the only place someone has shared that link including the user id. 132k is a lot of people and a lot of potential for link clicking

AncientSwordRage

@b_jonas I didn't think that on-site referrals 'counted'

b_jonas

@TheLethalCarrot Yes, I waas just wondering why that question had so many views.

TheLethalCarrot

@AncientSwordRage It's just unique IP addresses, I don't think it matters where the referral came from

Older question on a popular franchise and a relatively common question I'd imagine

b_jonas

@AncientSwordRage Unclear. Back when announcer badges suddenly got much easier to get, we talked about whether that changed, and there was contradictory info. I think comments and answers on sit within Sci Fi do count because I get many of my announcer badges that way.

AncientSwordRage

7

A: Does announcer badge count increase when link is opened from inside StackExchange network?

The Announcer badge (and it's silver and gold compatriots) only count links from outside the Stack Exchange network. Given that the default way of obtaining a link is to use the "share" option which adds your user id it can't really be described as farming - especially given point 1 above. Given...

20

A: Announcer badge spike

This is caused by the switch to HTTPS. Stack Overflow changed to HTTPS on May 22, and guess what happened. Here are the awarded Announcer badges on Stack Overflow: This has a technical reason. Visitors coming from within the Stack Exchange network didn't count towards the badge as they were f...

HTTPS masks the referer url, meaning you can't filter them out anymore

b_jonas

10:22

that's the relevasnt posty, and you can see in the comments that not everyone agrees

AncientSwordRage

@Braiam: Indeed. It's also easy enough to observe (e.g. using the developer tools built into most browsers nowadays) that Referer (sic) headers are getting sent for links between SE sites, even over HTTPS. Thus, I suspect the real cause is a bug in the SE referral tracking code, perhaps an old regexp getting confused by the extra s in the referrer URLs or something. — Ilmari Karonen Sep 6 '17 at 14:19

TheLethalCarrot

Was going to say, didn't think I'd shared any links outside of SE

b_jonas

I don't particully care enough to try to find out, I just put relevant links everywhere, on site and off site.

Rand al'Thor

@TheLethalCarrot Heh, fanfics and private parts. Someone is trolling you.

AncientSwordRage

@TheLethalCarrot all it takes is someone to copy the link you made with your ID to a popular site and BANG, ZOOM Straight to the MOON (where badges live)

TheLethalCarrot

10:23

@Randal'Thor Someone certainly was

b_jonas

I do share links outside of SE and I'm getting Announcers from that too.

for scifi.stackexchange.com/q/112202/4918 from an off-site link the most recently.

Rand al'Thor

@b_jonas You're the first person I'd expect to get Announcer/Booster/Publicist badges; you're always linking to everything using the share URL.

Apparently DavRob60 was the king of Publicist badges, back in the day. Fifteen of them in the first three years of the site's existence.

Maybe he had a popular blog or something.

b_jonas

@Randal'Thor I plead guilty. I specifically make my data.stackexchange.com queries show affiliate links. except to comments where that's not possible.

I even made that work cross-site no matter what site you run the query to.

Rand al'Thor

@AncientSwordRage Of course badges live on the moon. What do you think moon badgers eat?

@b_jonas Just because of that, you're one of the people whose user ID I always remember.

I didn't memorise its prime factorisation though.

b_jonas

@Randal'Thor On all SE sites?

TheLethalCarrot

10:31

@Randal'Thor I think I only know my own user id and user14111's :P

Rand al'Thor

@b_jonas Nooo

AncientSwordRage

I know another userID but not sure who's it is

2708

it's just a nice number

b_jonas

I don't remember my own ID on any site. not even on perlmonks where I have a longer presence that SO has existed and once had privilages.

AncientSwordRage

I think it's either DVK's or Slytherincess'

Rand al'Thor

@TheLethalCarrot I don't remember yours.

@AncientSwordRage Not on SFF.

DVK is 976, Slytherincess I think 3500?

AncientSwordRage

10:32

@Randal'Thor weird

Maybe that's my userID over on RPG?

Rand al'Thor

Smaller ones are easier to remember.

I remember Null's because it's so similar to mine (31394 and 31936).

TheLethalCarrot

I also know user931's

AncientSwordRage

@Randal'Thor ahh no my RPG ID is 2788

Rand al'Thor

@AncientSwordRage 2708 isn't prominent on RPG either.

b_jonas

I trust computers to remember this kind of thing, it's not my job. Plus I know what happens when I think I remember a number and so type it directly to the computer but I type the wrong number. Hours of debugging a segfault after which I realize that 1<<13 is not actually 8096 and I swear never to type large powers of two in decimal ever again in contexts where I can just type (1<<13) or 0x2000 and it just works.

Rand al'Thor

10:34

Or chat.

AncientSwordRage

my brain made it up then

b_jonas

And my conscience is good, that was many years ago and I kept that promise.

TheLethalCarrot

@Randal'Thor I only know mine from seeing it a lot in share links, when on my profile and when I've been doing user specific stuff in SEDE

Mithical

I think mine is... 33591?

I know my chat ID is 133031, that's easy to remember.

TheLethalCarrot

I don't think I've ever even looked at my chat id

Mithical

10:39

But I only remember the SFF one because it's been like six years.

SQB

11:04

Mine is a palindrome.

Or rather, it stays the same upside-down on a 7-segment display.

Which is somewhat palindromey.

AncientSwordRage

@SQB 7-seg ambigram

Rand al'Thor

11:20

@Mithical My chat ID is a Mersenne prime. Beat that :-P

Although I don't know if anyone here except @b_jonas will know offhand what a Mersenne prime is.

TheLethalCarrot

I've heard of them and used to know what they were if that counts

AncientSwordRage

11:37

@TheLethalCarrot primes in the form of (2^n)-1

Rand al'Thor

11:50

And important because they're the easiest big numbers to prove prime.

AncientSwordRage

@Randal'Thor also important for PRNGs

SQB

@Randal'Thor yes, I do.

2^p - 1 where p is prime itself.

There was a conjecture connecting them to perfect numbers, but I forgot what it was.

AncientSwordRage

> In the 4th century BC, Euclid proved that if 2p − 1 is prime, then 2p − 1(2p − 1) is a perfect number. In the 18th century, Leonhard Euler proved that, conversely, all even perfect numbers have this form. This is known as the Euclid–Euler theorem.

SQB

Ah, right.

AncientSwordRage

I often wonder what the connection is of Mersenne numbers to parts of a Collatz sequence

@SQB exactly ::shrug::

SQB

11:59

I remember reading about some bloke giving a lecture "on the multiplication of large numbers" or some such, where he, with saying a word, first multiplied 2 large numbers, then calculated a Mersenne number, which amounted to the same, thus proving it wasn't prime.

I think the story is in one of those books on numbers by Penguin.

Ah, it's in the Wikipedia article as well.

It was Lucas.

AncientSwordRage

Lucas numbers are cool

SQB

Nope, Cole, sorry.

Lucas just proved it wasn't.

AncientSwordRage

ah Lucas used a cole-thing to make it prove the non-primality

Rand al'Thor

@AncientSwordRage Prime Role Numbering Games?

@SQB Frank Nelson Cole, but I think that's a myth.

AncientSwordRage

@Randal'Thor basically

Rand al'Thor

12:03

Pre-computers, obviously.

AncientSwordRage

@Randal'Thor Pseudo-random number generators

Rand al'Thor

Oh right.

Yes, and everything else that relies on primality of big numbers, such as banking security.

AncientSwordRage

@Randal'Thor pretty much

although I have more of a thing for Collatz Sequences:

18

Q: Longest known sequence of identical consecutive Collatz sequence lengths?

I've just written a simple java program to print out the length of a Collatz sequence, and found something I find remarkable: Consecutive sequences of identical Collatz sequence lengths. Here is some sample output: Number: 98 has sequence length 25 Number: 99 has sequence length 25 Number: 100 h...

sequences-and-series collatz-conjecture

still blows my mind

Marvin

12:20

2

Q: Why didn't Wormtail leave Hogwarts as soon as he saw Harry in possession of the Marauder's Map?

Wormtail used to live in Gryffindor's common room as Ron's pet. He was also one of the makers of the Marauder's Map and hence was aware of its working. So didn't he fear that someday Harry might see one dot labelled Peter Pettigrew in the boy's dormitory and his secret might get exposed?

harry-potter marauders-map

Donald.McLean

@AncientSwordRage Math can be fun. It can also be a huge pain.

AncientSwordRage

@Donald.McLean agreed

Do you ever peruse Worldbuilding by any chance, by the way?

Donald.McLean

12:35

It is possible that, at some point, I might ask a question there, but I don't generally read or answer questions on that site - it's a bit of a rabbit hole. :-)

AncientSwordRage

12:59

@Donald.McLean certainly can be

I've been asking questions there about Sci-Fi and Space topics

Donald.McLean

@AncientSwordRage I have a couple of personal projects I'm working on where some outside assistance would be useful to make sure I haven't overlooked something.

AncientSwordRage

@Donald.McLean that's sort of where I am as well

It always seems like when I ask a question there I get feedback like "We can't really answer how you want because your assuming something that's unreasonable" which is helpful, even if it's not the help I want

Rand al'Thor

Perhaps if someone who has contact with him would let him know that he was chosen for a topic challenge, he'd be willing to peek in a couple of times this month... — Basya 38 mins ago

@AncientSwordRage you mentioned having contact with Thaddeus via Twitter?

AncientSwordRage

@Randal'Thor I follow him, no idea if he'd respond if I tweeted or if he has DMs switched on

(direct messages)

@AncientSwordRage for instance if you want to land a space ship, it helps if it's not 750km long

Rand al'Thor

13:14

A lot depends how much you're willing to ignore real science for the sake of Rule of Cool.

If it's not hard sci-fi, you can get away with some degree of nonsense.

AncientSwordRage

@Randal'Thor I like leaning towards hard sci-fi, to the extent that I'd like stuff to be science based and not so crazy you can't suspend your disbelief

I picked 750km as it's the length of the North Eastern Corridor railway

Donald.McLean

13:33

@AncientSwordRage That seems kind of like an obvious thing, to me. A ship that long landing on a planet would run into issues with the planet's curvature, so a fairly small part of the ship would touch the planet, and that would exert a huge load both on that part of the ship and on the corresponding part of the planet.

TheLethalCarrot

Just space elevator "land" the ship

AncientSwordRage

@Donald.McLean makes sense to me

Rand al'Thor

@Donald.McLean Unless you have a really really long landing strip.

Donald.McLean

@Randal'Thor You could only do that on a planet with no tectonics. It would require digging a trench deeper than the Earth's crust. And it would probably require a planet with effectively no atmosphere, as something that large would cause catastrophic atmospheric storms. Perhaps a tidally locked planet with almost no rotation as well. Then it would just be a question of engineering the landing gear and/or cradle, which is not going to be easy.

AncientSwordRage

@Donald.McLean it would have h = ~240km 'up' on each end

Circular segment

In geometry, a circular segment (symbol: ⌓) is a region of a circle which is "cut off" from the rest of the circle by a secant or a chord. More formally, a circular segment is a region of two-dimensional space that is bounded by an arc (of less than Π radians by convention) of a circle and by the chord connecting the endpoints of the arc. == Formulae == Let R be the radius of the arc which forms part of the perimeter of the segment, θ the central angle subtending the arc in radians, c the chord length, s the arc length, h the sagitta (height) of the segment, and a the area of the segment. Usually...

so, like @Donald.McLean says pretty much impossible

DavidW

13:51

Unless your ship has a concave underside matching the curvature/shape of the body you're landing on.

AncientSwordRage

@DavidW I'd rather it didn't

Donald.McLean

This is one of those situations where there's basically no use case that justifies the effort. The only reason to do something like that would be "because we can" which falls into the same category as drinking a 12 pack of beer.

b_jonas

@Randal'Thor Yes, but there are probably infinitely many Mersenne primes so that's not very special :-)

AncientSwordRage

The use case is that the AI was challenged to find a way to minimise the effects of climate change on humanity, and it's answer was "Find a new planet, exhausting all the resources on earth in the process"

DavidW

(Think Ra's ship in the original Stargate.)

AncientSwordRage

13:54

It's not the same as the AI drinking a 12 pack, but it's in the same ballpark

@DavidW except my proposed ship is probably 3000 times larger

I think I did the maths of the segment height wrong

Rand al'Thor

@DavidW Or if your planet is polyhedral.

Apparently there's a bunch of Worldbuilding questions about cube-shaped planets.

TheLethalCarrot

Has something changed with the font sizes on the main site? I feel like the screen is at 120% zoom even though it's still normal at 100%

DavidW

14:10

@AncientSwordRage 240 is way too high; Pythagorean theorem tells me 11km.

AncientSwordRage

@DavidW sure? 11km seems way to low to me

DavidW

Pythagoras is pretty simple, you can check my math yourself. sqrt(r^2 + 375^2) - r

b_jonas

@Donald.McLean No of course not. That's like saying "if the world is round then how can highways/bridges be straight." The spaceship would just have legs or wheels, probably adjustable if there's more than one, rather than lying on its belly. Spaceships that land do that anyway, even small ones, because you want to be able to go under them to repair the rocket exhaust port. Or it levitates if this is Star Wars because they don't use wheels.

AncientSwordRage

@b_jonas no wheels and no guard rails

b_jonas

148

Q: We are switching to system fonts on May 10, 2021

Update 3 - The changes from round 2 are live, but with one notable exception: On Linux, we spec’d “Liberation Sans” and “Liberation Mono”. Did some digging on that PR and installed a few Linux VMs and found Liberation to be the best way to normalize across Linux distros. It also solves an issue w...

discussion design stack-exchange fonts

TheLethalCarrot

14:24

I feel like somethings changed a bit more recently than the initial fonts change

b_jonas

@AncientSwordRage But they have tracked vehicles at least, in Rogue One.

How those tracked vehicles work without wheels is a mystery.

AncientSwordRage

@DavidW oh that makes me feel dumb

@DavidW Math.se are going to have a field day

AncientSwordRage

14:52

@DavidW feel free to answer this: math.stackexchange.com/questions/4160031/…

Rand al'Thor

@AncientSwordRage How do you measure the height of the struts: perpendicular to the flat line at their top, or perpendicular to the earth's surface at their base? The meaning of "vertical" becomes ambiguous here.

DavidW

@AncientSwordRage Tempting, but I already spend too much time on SF&F. I don't need to join another stack; go ahead and self-answer.

AncientSwordRage

@Randal'Thor D:

DavidW

@Randal'Thor "Vertical" is established by the local gravitational field, so it's the latter.

The question isn't asking about struts, it's asking for height above ground which is pretty unambiguous.

Rand al'Thor

Assuming this interpretation of "height" ^, if you have a planet of radius r and you want a flat runway of length x, then there's a right-angled triangle with short sides r and x/2, so it's just Pythagoras. The height of each strut above the planet's surface will be \sqrt{r^2+(x/2)^2} - r.

So @AncientSwordRage I think you're making it more complicated than it needs to be.

Donald.McLean

15:11

@b_jonas It's a question of scale. A 1km long ship, sure. A 10km long ship, maybe. But the ship in question is 750km long, and no, at that point the curvature is absolutely a serious problem.

AncientSwordRage

@Randal'Thor par for the course with me

@Donald.McLean you're right, an overhang of 11km is too much

@Donald.McLean even 50km makes the overhang/sagitta 50m/150ft

10km makes it 2m

DavidW

15:36

@AncientSwordRage That accords well with the visual horizon in flat terrain.

AncientSwordRage

15:49

I guess the issue now is to figure out what the closest to 750km you can get within acceptable material strength parameters

DavidW

You could just change the size of your planet.

AncientSwordRage

@DavidW oh yeah

Cereal Bot

16:43

Saturday Morning Breakfast Cereal: Saturday Morning Breakfast Cereal - Engineering

posted on June 03, 2021 by tech

Click here to go see the bonus panel!Hovertext: This is mostly a joke, but the canards would actually work. Today's News:

Marvin

17:19

2

Q: Story identification: Wing suits are required to travel between islands, a girl is about to lose her wings

I believe this was in a sci fi collection from 1975 or 1976 or somewhere around there. It was sci-fi ish, on a planet consisting of islands. In order to communicate between islands people have to put on wings, or wingsuits or something like that. Only certain people are allowed to have wings. ...

story-identification short-stories

AncientSwordRage

17:51

in TRPG General Chat, 45 mins ago, by Feeds

Needles & Nilbogs: My case against dystopias, and a few suggestions

posted on June 03, 2021 by Bardic Wizard

Over last weekend, I went camping with my family. It was nice to be out in the fresh air and with people I love, and I got to play with fire a bit, so it was very fun. But it got me thinking about books, because lately, I’ve been reading a bunch of young adult (YA) and middle grade literature, and I brought a few amazing books on the trip to (re)read. And because the library’s Summer Reading Ch…

Interesting books recommendations inside ^

Marvin

18:09

0

Q: Does Dualla's suicide have anything to do with Gaeta's mutiny?

In Season 4 Episode 11 ‘Sometimes a Great Notion’, we see Anastasia Dualla commit suicide, just moments after talking with her friend and bridge co-worker Gaeta. Did her suicide have anything to do with the downfall of Gaeta and his eventual mutiny against Adama? During Gaeta's time on the Galat...

battlestar-galactica battlestar-galactica-2004

DavidW

19:56

@AncientSwordRage I was a lot more tolerant of SF dystopias when it didn't seem like we were barreling at full tilt into one ourselves.

Though modern YA dystopias are so lazy and cardboard they grate on many levels.

Mithical

@DavidW I read something really interesting recently about what caused that. Let me see if I can find it.

DavidW

Why can't stories featuring YA protagonists be more like, say, Vinicoff's "Windrider" (for a comparable post-apocalyptic setting, but a positive outlook and adults as Reasonable Authority Figures) and less like... all the rest.

AncientSwordRage

@Mithical I'm also curious

I've not read enough to know either way

Mithical

....can't seem to find it right now. It had to do with Divergent, and how the movie rights were sold even before the book was published.

Mithical

20:20

Grrr. My Google-fu is failing me, and it's not in my browser history that I can find.

Marvin

20:40

0

Q: What is the ficitonal date range for "The Children of Night" by Frederick Pohl, (1964)?

"The Children of Night" by Frederik Pohl was first published in the October 1964 issue of Galaxy Magazine, and has been reprinted a number of times. http://www.isfdb.org/cgi-bin/title.cgi?57220[1] I suppose that many users of this site should have access to books where it is reprinted. The locat...

short-stories

Adamant

21:04

@Mithical I think it was just Hunger Games and a case of following the leader.

Just like after Twilight we saw a pile of supernatural urban fantasy romances with love triangles, and these days a lot of YA fiction has some elements of both.

Still,

Still, I am not sure we have yet reached the level of the isekai market, where "character is stuck in a tutorial level for centuries and comes out with a low level but high hidden statistics" is a whole genre in itself.

Transcript for

The Restaurant at the End of the Univ…