The h Bar

@heather It is not completely impossible that there is - I know quantum mechanics very well but quantum computing is not my area of expertise, after all

heather

12:12 AM

I'll wait till @DanielSank is next in here and ask for his opinion then

until then, I will think of Star Wars: Episode IV and hope my situation is similar.

dmckee

@BernardoMeurer ::chortles::

Bernardo Meurer

@dmckee This is some hard stuff

dmckee

I'm reasonable sure that the diagrams are the natural way to read data-flow programs. But I am absolutely sure that there should be a better way to program them than by pointing and clicking.

And I won't talk about debugging. I just won't.

Bernardo Meurer

I cannot debug this thing

Cannot

It's so shitty I just have a 4-bit signal and I cannot understand what it does

peterh

@ACuriousMind Check also the novel if you didn't, it has interesting additions to the Nameless' story.

dmckee

12:18 AM

@heather If you get the Team Negative One restored theatrical print you will not only see the very best version of that movie, but you will see that it originally didn't have any silly episode numbering: it's just plain 'ole Star Wars and no mucking about.

heather

@dmckee that would be cool

i will put that on my "someday when I am an adult and hopefully have money" list

dmckee

@heather It's on bittorrent. Just 23 GB.

0celo7

@heather Ok I'm liquored up. Banach spaces

Do you know what a vector space is?

heather

@dmckee I will make note of that

@0celo7 I think...?

perhaps a review would be good

0celo7

@heather can you provide a brief description so we're on the same page?

heather

12:21 AM

a set of vectors that is closed under addition and multiplication by scalars?

0celo7

More like a set of stuff with two operations, and we then we call them vectors

but basically yes

heather

okay.

0celo7

@heather do you know what a norm on a vector space is?

heather

@0celo7, well a norm on a vector is the magnitude of the vector if i remember right

but i'm not sure what a norm on a vector space is

0celo7

@heather so you know what the "usual" norm in $\Bbb R^3$ is?

$||\mathbf x||=\sqrt{x^2+y^2+z^2}$?

where $\mathbf x=(x,y,z)$

heather

12:32 AM

yep.

0celo7

@heather ok, so this has some nice properties

@heather if $a\in\Bbb R$ then $||a\mathbf x||=|a|\cdot||\mathbf x||$

agreed?

heather

yeah

0celo7

@heather how about $||\mathbf x+\mathbf y||\le ||\mathbf x||+||\mathbf y||$?

DanielSank

@heather calm, calm

heather

@0celo7 that makes sense - but why would it be less than?

@DanielSank i have calmed down a bit

listening to some music does that for me - also, flipping through nature magazine and talking about math with 0celo

Bernardo Meurer

12:42 AM

@heather Death Grips is great for calming down

heather

the Shins are pretty good

same with Radical Face's Welcome Home

0celo7

@heather think of the triangle $\mathbf x,\mathbf y,\mathbf x+\mathbf y$

you know that the sum of two side lengths of a triangle cannot exceed the third

that's exactly what this is saying

heather

oh, okay.

Bernardo Meurer

"Linux Sucks... For the Last Time" - 2017

►

:')

0celo7

@heather ok, the third property, the most important one, is $||\mathbf x||\ge 0$ for any vector $\mathbf x\in\Bbb R^3$, and $||\mathbf x||=0\implies \mathbf x=\mathbf 0$.

heather

12:49 AM

okay, that makes sense as well.

0celo7

@heather Ok, consider a general $\Bbb R$-vector space $X$. A norm is a function $X\to\Bbb R$ such that

(i) $\forall x\in X:||x||\ge 0$ and $||x||=0$ iff $x=0$.

(ii) $\forall a\in\Bbb R,x\in X: ||ax||=|a|||x||$.

(iii) $\forall x,y\in X: ||x+y||\le ||x||+||y||$.

Make sense?

heather

what's the upside down A mean?

0celo7

for all

heather

so a norm on a vector space is a function that takes in the vector space and outputs things in R such that all three properties of normal norms are followed?

0celo7

yes

heather

12:57 AM

okay, I think I follow then.

0celo7

@heather do you rememer limits of sequences from calculus

heather

@0celo7, I believe so.

i probably don't know it as rigorously as I should, however.

0celo7

If yes, consider the following: Let $(x_n)\subset X$ be a sequence ($n=1,2,\dotsc$). We say that $(x_n)$ converges to $x\in X$, written $x_n\to x$, if $(\forall\epsilon>0)(\exists N\in\Bbb N): n\ge N\implies ||x_n-x||<\epsilon$. We also write $\lim_{n\to\infty} x_n=x$, and say $x$ is the limit of $(x_n)$. For brevity we also write $\lim x_n=x$.

@heather I'll let you review it

ping me if you have questions

heather

what is the backwards E @0celo7

0celo7

this is the fundamental concept of analysis

@heather "there exists"

peterh

1:02 AM

@BernardoMeurer Linux is also a fight for freedom.

Bernardo Meurer

@peterh Watch the video

heather

1:21 AM

I think I deciphered each individual symbol, but I'm not sure what they mean as a whole.

@0celo7

BuddyJohn

what lead to this exposition on Banach spaces?

Or is this like "math lesson of the day"

Secret

Small quantum question: Is it true that for an antisymmetric wavefunction, the amplitude for a set of variables is always anticorrelated to the amplitude for another set of variables?

heather

okay, I think I've further put it together, but I am still unsure about the meaning of $(\forall\epsilon>0)(\exists N\in\Bbb N): n\ge N\implies ||x_n-x||<\epsilon$.

@0celo7

@DanielSank, are you still around?

BuddyJohn

for any arbitrarily small value, we can always find an element that is within that small value of what we are saying is the limit

indeed, this is actually defining what we mean by "the limit" of a sequence

heather

@BuddyJohn for all "small values" greater than zero, there exists a set $N$ in the set of natural numbers such that the sequence $n$ is greater than or equal to $N$ where the norm of the sequence minus the limit of the sequence is less than the "small value".

your explanation makes tons of sense

thank you.

@0celo7 I think I may understand it now.

dmckee

1:38 AM

I basically stopped fighting the good fight for linux when Mac OS X started running all the particle physics stuff I needed reliably.

Now I write LaTeX documents in emacs on Mac OS.

Which is just weird.

But it works.

heather

@dmckee, I'm considering contacting a professor at a university near me. What should I not do? Is there any etiquette I should follow?

dmckee

And every system works on day one without me having do spend hours fighting with it.

@heather Tell him/her who you are and why you're contacting them early. It lets them get into the right groove to respond (or just to tell you no early on, but we can hope that isn't the case).

heather

@dmckee, okay. Is there anything professors hate being asked, or told, or anything like that?

dmckee

That's pretty good advice for reaching out to almost anyone. Unless you're one of those people who can read and manipulate others.

@heather "Did I miss anything important?" would be a favorite

But from the point of view you bring it's probably asking to join one of their project before you have convinced them that you might have something to offer.

heather

@dmckee not really, as far as I know.

dmckee

1:43 AM

Now, you are actually pretty special for your level of formal preparation, but they won't know that right off.

heather

@dmckee okay, I'll keep that in mind.

@dmckee so, this professor works with a research group on computing with DNA and nanotechnology; I was planning on a. reading up on it, b. reading some of that group's papers, and c. explaining that I was doing research on quantum computing and working on a program that would simulate hopefully both an ideal and non-ideal quantum computer and kind of see what happened...

is this a poor approach? (this group is the closest group I could find to my own interests, except for a guy who may not even still work at the university).

dmckee

So. You might have something to offer. That's good.

heather

that was my hope.

dmckee

You want to sell them on what your work might do for them, but don't make unrealistic claims.

heather

okay.

I wonder if the code I write would be useful for simulating the type of computers they are working on.

might have to read about that.

dmckee

1:48 AM

An important thing that young programmers don't understand is the difference between a demo program that works on your machine and a program that can be installed elsewhere and will work when you've done that.

heather

also, at what point should I mention that I'm a nerdy middle schooler? I feel like that will significantly reduce my credibility.

dmckee

Work without tinkering.

heather

@dmckee hmm. so should i try to make my program something that can be connected to a web interface or something?

dmckee

@heather Well, there is some risk of that, but if they will react badly to it, there is a risk that they will feel tricked if you hold out on them.

Don't make it item 1, but fess up early on.

heather

will the professor ask at some point if I'm an undergrad or grad student or anything?

because that would be a nice point to mention that.

dmckee

1:50 AM

@heather They might. Take it as a complement if they think you're a undergrad.

Take it has a huge compliment if they think you might be a grad student.

heather

@dmckee yeah, I don't think they will =) I meant if there will be a point at which they ask what I'm currently doing, if that makes sense.

dmckee

Keep in mind that professors vary as much as any other people, so good advice in general might be poor advice for some particular person.

heather

okay.

too bad there isn't a way to learn about a professor besides their website and research papers.

dmckee

@heather Look for blogs of social media accounts of people who work for them.

You probably won't find much, but that is mostly a good sign.

Really bad bosses generate comment.

heather

okay, i'll check that.

thank you for all of the advice!

Secret

1:58 AM

Suppose I have the following antisymmetric wavefunction $\lvert r_1\rangle\lvert r_2\rangle-\lvert r_2\rangle\lvert r_1\rangle$ Then suppose I pick points $r_1=a$ and $r_2=b$, I get amplitudes $c,d$ for the 1st state respectively at those points, and $e,f$ for the 2nd state respectively. Now for the antisymmetric wavefunction, the amplitudes at the coordinates $(a,b)$ will be given by the difference of the ampltudes $cd-ef$ which is not zero in general.

However if I pick the points $r_1=r_2=a$, then I get $cd-cd=0$, therefore showing pauli exclusion. Does that suggests the amplitude of the…

BuddyJohn

@heather Even when I was a gradstudent, it would sometimes be hard to get some feedback from a professor.
On the flip side, I would sometimes get emails from students out of the blue asking if I would help with some project. No one wants to agree to something to open ended or too much time.
Sending a write up, and saying this is what I'm working on, can you help me? or is this interesting to you? I think would not go well.
Yet asking direct questions, or asking if you can just stop by and ask questions during an office hour, would probably go over well.

heather

okay @BuddyJohn, I'll keep that in mind.

I was kind of hoping to maybe be able to possibly work in the lab with that group.

(I don't think I had enough qualifiers in that sentence =P)

Bernardo Meurer

What's up?

heather

@BernardoMeurer, asking questions about how to talk to professors about doing research with them and/or their group

Bernardo Meurer

@heather Hm, My professor invited me to join his research after the first semester

Not sure what to tell you though

I'm just a CPU nerd and he works on that

And he caught me trying to run Emacs on my calculator during a lab

He was sold, lol

BuddyJohn

2:12 AM

There are two sides to this, so you also want to find out if you want to work with them.

If they are open to you stopping by to ask questions, which will likely lead to you explaining how it relates to something you are working on, is a great way to see if you'd even like to work together as a mentor like relationship on a side project.

Bernardo Meurer

He's an amazingly cool dude though, gives me shit when I'm being a rat and I appreciate that

BuddyJohn

@BernardoMeurer so you had a class with him first?

that definitely makes it easier, since he knows some of your interests, capabilities, and enthusiasm level

Bernardo Meurer

Yeah, he taught the lab classes and practice classes for my Digital Systems course

And we started talking after class once because I was talking to a classmate about possible improvements on branch prediction techniques by using neural networks, and the prof wanted to hear more

BuddyJohn

neat

oh, so you are in computer engineering / computer science? Mind if I ask a question?

Bernardo Meurer

I'm a Computer Engineer, yeah

Although I generally think maybe I should be a Computer Scientist, but that's another talk

BuddyJohn

2:19 AM

I can't follow what they mean by a "branching program" in this wiki description en.wikipedia.org/wiki/NC_(complexity)#Barrington.27s_theorem

searching "branching program" on wiki takes me to binary decision trees, which sound nothing like what they were describing

Bernardo Meurer

@heather Just be yourself, I know you're enthusiastic about what you study. Be dedicated and, "know your shit", good professors and researches will see the value in you for that, and then you will need to do little work to convince them to do research with you.

heather

@BernardoMeurer, thank you.

Bernardo Meurer

@BuddyJohn I think they're talking about consecutive decision kind of problems, which do resemble a binary tree

BuddyJohn

@heather what are you currently using to study quantum computing? I just started reading a book that introduces it only using linear algebra. Seems okay so far.

Bernardo Meurer

I'd have to be less sleep deprived than I am now to give a better explanation, are you comfortable with the formal definition of a Turing machine?

BuddyJohn

2:23 AM

Yes, but I'm not sure I could actually program a turing machine to do something useful.

Bernardo Meurer

Because that one there just seems like a normal turing machine where the transition function is crafted to make binary choices based on state

heather

@BuddyJohn a combination of things. I have as reference Nielsen and Chuang's quantum theory and quantum information. I learned the basics of linear algebra using 3Blue1Brown's videos on YouTube. I watched some of Michael Nielsen's videos on quantum computing on YouTube. I have talked with Daniel Sank, he's a quantum computer engineer who frequents the hbar.

I cannot profess to know very much about the topic though. I need to have more rigorous foundations in QM and CS.

Bernardo Meurer

@heather If Daniel is a computer engineer than my mother is a goddamn cosmonaut

:P

BuddyJohn

@BernardoMeurer I guess I am confused because it is referring to variables, yet their description doesn't seem able to set any of the variables.

Bernardo Meurer

He's a pesky physicist

BuddyJohn

2:25 AM

doesn't even sound like a variable them

Bernardo Meurer

Ah, because it's on a tape :)

I think

heather

@BernardoMeurer lol, I didn't know what to call it. a quantum computer physicist, then.

BuddyJohn

If you are interested in the computing aspects, I don't think you need a very rigorous foundation in QM.

Bernardo Meurer

@BuddyJohn Yes, yes, it's a tape

The branching thingy is just a particular type of transition function for the Turing machine

Xablau

heather

could the variables be nodes @BuddyJohn?

nvm, I don't know what i'm talking about =)

BuddyJohn

2:28 AM

Okay, so they aren't variables in the usual programming sense, they may be better described as "the input"?

@heather The book I just started is "Quantum Algorithms via Linear Algebra"

heather

@BuddyJohn hmm, that sounds quite interesting

Bernardo Meurer

Hm, I think P != NP

Hm

Sir Cumference

Anyone want to hear a joke?

Bernardo Meurer

Dammit

DanielSank

@heather what's up?

BuddyJohn

2:30 AM

it was written by a computer scientist, so they introduce only as much quantum foundations as necessary to get you up and running.

DanielSank

I'm kinda distracted, unfortunately.

Bernardo Meurer

@DanielSank Lies, we know you don't love us

heather

@DanielSank, okay, it's not uber-urgent or anything. =)

Bernardo Meurer

We are your neglected children

heather

not children, padawans

@BuddyJohn that sounds extra good

Bernardo Meurer

2:34 AM

@BuddyJohn Jesus, 240 bucks for that book

uff

BuddyJohn

? it was cheap when I got it

I think I paid like $25

Bernardo Meurer

Wat

it's 45 on MIT's website

but 240 on Amazon

go figure

heather

well then.

BuddyJohn

Huh, I see 45 on amazon for new hardcover, 32 for ebook, cheaper for used

Bernardo Meurer

Okay, maybe I do need to go sleep

heather

2:39 AM

oh, i see 45 too

phew

BuddyJohn

something you might find interesting since you are writing a classical computer simulation of a quantum computer : arxiv.org/pdf/quant-ph/0406196.pdf

heather

thank you @BuddyJohn, that looks exceedingly interesting

BuddyJohn

apparently an algorithm only using CNOT and Hadamard gates can be efficiently simulated with a classical computer

which is deeply non-intuitive to me, since CNOT gates can be used to produce entanglement

heather

any algorithm or an algorithm?

BuddyJohn

any

it blows my mind

heather

2:45 AM

wow.

BuddyJohn

so I guess you need to include Toffoli gates if you want any chance of a quantum algorithm providing exponential speed up

Bernardo Meurer

Okay kids

I'm going to go sleep

Goodnight to y'all

0celo7

@heather ok, do you understand convergence of sequences?

heather

@0celo7, sorry, I have to go

@BernardoMeurer, good night

0celo7

bye

heather

2:56 AM

good night.

skullpetrol

Cya peeps :-)

skullpetrol

3:32 AM

Yes? @SirCumference

Sir Cumference

@skullpetrol Why couldn't the bicycle stand up on its own?

skullpetrol

Hmm...

...the kick stand wasn't down?

Sir Cumference

It was two tired (read like "too tired")

skullpetrol

ba dum tss

0celo7

my cat is looking at me

what should I do

skullpetrol

3:38 AM

Einstein?

0celo7

yes

skullpetrol

Show him The Evidence.

Einstein will always search for that, no?

DanielSank

@BernardoMeurer ?

@heather what's up?

skullpetrol

@DanielSank we have a potential new guest for AMA

BenNiehoff

0celo7

@skullpetrol Einstein left

skullpetrol

3:50 AM

:(

and now you're the only one left?

0celo7

He's in the next room eating I think

skullpetrol

How was the drive in the snow?

0celo7

almost died

skullpetrol

:-O

Get some chains for your tires pal.

0celo7

I live in the south

Balarka Sen

3:55 AM

either that or try to die next time

0celo7

no way Jose

@BalarkaSen delicious

Balarka Sen

i didn't know you had a death fetish

0celo7

I like a good edgy teen

Balarka Sen

kewl, me 2

0celo7

@BalarkaSen r/imgoingtohellforthis

Balarka Sen

3:57 AM

... i really thought that one doesn't exist

0celo7

what?

skullpetrol

^

Balarka Sen

@0celo7 I thought you just made it up, googled it, changed my mind

lol

skullpetrol

:D

0celo7

I think I survived

But you can get suspended after deleting things

@BalarkaSen check it out bruh

it's pretty edgy

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