The h Bar

@0celo7 Chop off the part of the Cauchy sequence with distances larger than 2/3, it stays a Cauchy sequence and if it converges, the original sequence also converges (since you chopped off finitely many elements)

0celo7

...yes...

ACuriousMind

The chopped off sequences now converges if the open ball is precompact, since compact metric spaces are complete, so the closed ball is complete as a metric space hence the chopped off Cauchy sequence converges, no?

0celo7

Ok if I cut off those terms, how do I find a unit ball that contains the sequence

just pick any of the terms as a center?

ACuriousMind

Well, it's probably easier to chop off to distance 1/3 and just pick any point of the remaining sequence as center

0celo7

why 1/3

ACuriousMind

8:16 PM

...because you had given that 1/3 balls are precompact?

0celo7

oh, I can probably just scale the metric, no?

ACuriousMind

What?

Balarka Sen

@ACuriousMind what's your avatar

it was troll before.

0celo7

if $B$ is a 1/3 ball wrt. $d$, then $B$ is a unit ball wrt. $3d$.

ACuriousMind

@BalarkaSen Kreia from KotoR 2

0celo7

8:17 PM

or $d/3$

ACuriousMind

@0celo7 Yeah, but why do you want to scale anything

0celo7

something

@ACuriousMind Because unit balls are nicer than 1/3 balls.

more aesthetically pleasing.

ACuriousMind

Given that balls with radius $r$ are compact, just chop off the Cauchy sequence to distances less than $r$. Nothing in my argument relies on the value of $r$.

Balarka Sen

@ACuriousMind I had to google what that is.

0celo7

I like pretty numbers

@BalarkaSen agreed, video games are boring

ACuriousMind

8:18 PM

@BalarkaSen I expected that ;)

0celo7

it's time for a new avatar for me

I literally have no clue what the fuck this line means in my EM lab

"Estimate the change in the light emitted from bulb #1 when the second bulb was added? 1X, 2X, 3X, 4X, 8X, 3/4X, 1/2X, 1/3X, 1/4X, 1/8X?"

ohhhh

that X is a times!

Balarka Sen

...

OK. There's too many things I have to do but I can't decide what to do.

And whenever I try to get something done, the rest of the stuff that I have to do keeps distracting

A philosophically challenging dilemma

maybe the solution is to grab some snacks, watch a movie and sleep.

0celo7

I'm currently deciding how to learn some more Riemannian geometry

peterh

8:39 PM

@0celo7 Actually, there is 2 important thing to calculate: 1) shading of the bulbs of the light of the other 2) our senses are logarithmic

0celo7

What?

peterh

Although I am not sure. My second impression is that a lighting light bulb should have a nearly 1 albedo for its own light.

Sir Cumference

9:00 PM

@dmckee Hey, you mind if I ask a question?

@dmckee Er, you there?

@0celo7 He's right when he says our sense are logarithmic. Imagine looking at one bright lightbulb, and then looking at two bright lightbulbs. A big difference in brightness, right? Well, now imagine looking at 99 bright lightbulbs, and then looking at 100 bright lightbulbs. The change doesn't seem that apparent. Even though the difference in the number of lightbulbs is the same, we wouldn't tell much of a difference in the second scenario.

Bernard Meurer

Howdy

Sir Cumference

@0celo7 It's because our senses work logarithmically. In the first scenario, twice the light was added. In the second scenario, a much smaller fraction of light was added (99/100).

@0celo7 We also detect sound the same way and even count the same way. For example, there's a big difference between being chased by one lion, and being chased by two. However, there doesn't seem to be a big difference between being chased by 99 lions, and being chased by 100. Our brains register numbers logarithmically, so we wouldn't be able to tell the difference in the second scenario, since only a small fraction was added.

Bernard Meurer

It doesn't make a difference from 1 lion to 2 for me

Both end with me dead

I don't see your point

user218912

9:27 PM

@BernardMeurer hi

Bernard Meurer

@3705 Back to this name? How have you been?

user218912

bad.

Bernard Meurer

Bought blue pants today, thought of you lol

user218912

xD

Bernard Meurer

What's up?

user218912

9:27 PM

ever since my lung collapsed I've been downhill in everything.

Bernard Meurer

Define everything

user218912

I have been gaming for 3 months now for hours everyday without reading or learning anything.

Bernard Meurer

You're a physics major, have some rigor :p

user218912

I forgot everything I learned.

user218912

all of it.

Bernard Meurer

9:28 PM

What's a tensor?

user218912

I still remember that xD

user218912

but I forgot everything else.

Bernard Meurer

See :p

Well, you'll have to learn it in College

You'll be just fine

user218912

I know that.

user218912

but I lost my lead.

user218912

9:30 PM

I'm gonna stop gaming now...

user218912

but Idk how to get back into reading.

Bernard Meurer

Usain Bolt has a bad start but still wins

@3705 Start with something you like a lot

like Kernels

Everyone loves that

user218912

idk what I like anymore.

user218912

I don't like anything, so I'll probably start fresh in something new.

Bernard Meurer

@3705 You're having an existential crisis

Breathe slowly and FREAK OUT

user218912

9:39 PM

xD

user218912

did you prepare for uni?

user218912

where are you right now?

Bernard Meurer

I'm in Rio still

I move to Lisbon Monday

p. anxious

user218912

good luck :D

user218912

I move in sunday, but it's only a 30 min drive xP

Bernard Meurer

9:40 PM

Are you getting a roomate assigned?

user218912

yes I found one already.

user218912

It's a dorm style room.

Bernard Meurer

Is he cool?

Are you cheating on me?

user218912

lol

Bernard Meurer

You said I was the only one

user218912

9:41 PM

well he's doing compsci like you.

Bernard Meurer

DUDE

YOU CAN'T DO THIS

;-;

user218912

he chose me.

user218912

in the roommate finder.

Bernard Meurer

Jokes apart glad you found a compsci dude

they're the second best people out there

they lose to CEng

user218912

do you have a roommate?

Bernard Meurer

9:43 PM

Nope

I got me a single room

user218912

nice.

Bernard Meurer

I fart a lot

it would be an issue

user218912

lol I'm sure it would.

peterh

This is non-mainstream ($\approx$ pseudoscience) or not?

physics.stackexchange.com/review/low-quality-posts/144484

user54412

10:10 PM

@dmckee Do you know if it's usual for postdoc positions to be exempt from social security?

0celo7

@ChrisWhite Sure isn't

Unusually high rate of suicide in that profession

@BernardMeurer that's the worst

Bernard Meurer

@ChrisWhite Hey Dr.White ;)

0celo7

@BernardMeurer currently getting all my farts out while my roommate is away

user54412

I should spend the next month ending arguments on the internet with "oh yeah, and when did you get your PhD in astrophysics?"

0celo7

try that on some gangsters in LA

please report results

user218912

10:24 PM

@0celo7 hey

user54412

I've wandered the gang-y parts of LA -- some good food can be found there

0celo7

@3705 what

lol you should have taken my Rudin analysis course

one of the books is Rudin...functional analysis

user218912

I'm dumb now.

user218912

I can't do anything.

0celo7

why

user218912

10:29 PM

because I was gaming everyday for 3 months

user218912

forgot everything

0celo7

See @ACuriousMind

user218912

what is he supposed to see?

0celo7

gaming destroys the mind

I'm on a strict diet of mathematics and trap

it's serving me well

user218912

it doesn't destroy the mind...

user218912

10:31 PM

it just wastes time and makes you forget stuff.

user218912

besides didn't you game 24/7 last summer?

0celo7

Yes, and it ruined me

I gave up physics in that time

dmckee

11:00 PM

@ChrisWhite New one by me.

Any chance they're talking about it being an "exempt position" for the purposes of labor law?

That would mean salaried rather than hourly and is usually the case.

Physics Meta

11:26 PM

0

Q: My profile picture pattern just changed automatically; how can I restore the old one?

Title says it all. My profile picture pattern just changed automatically: I liked my old one better. How can I restore it?

Emilio Pisanty

11:43 PM

So, question: would a name like "Blum Blum Shub" stick for a result in physics?

Blum Blum Shub

Blum Blum Shub (B.B.S.) is a pseudorandom number generator proposed in 1986 by Lenore Blum, Manuel Blum and Michael Shub that is derived from Michael O. Rabin's oblivious transfer mapping. Blum Blum Shub takes the form x n + 1 = x n 2 mod M {\displaystyle x_{n+1}=x_{n}^{2}{\bmod {M}}} , where M = pq is the product...

I contend that if Blum, Blum and Shub published some important result, most physics communities would go with something slightly less silly-sounding.

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