The h Bar

Anonymous

8:00 AM

But first of all I need to improve my knowledge of IOT and physics related to antennas and power transfer. I did find a few good books.

John Rennie

@Kaumudi.H back so soon? :-)

user228700

Yes, I had gone out to acquire the physical copy of my license, in addition to returning that book to the library, seeing as I'm leaving in three days.

user228700

I also did something quite obviously un-girly. Do you know about the method of threading?

John Rennie

@Kaumudi.H Yes, though I have never done it myself.

user228700

Well, I did it today because my eyebrows (used to) have the shape of a stick.

user228700

8:15 AM

@JohnRennie Ah :-(

John Rennie

@Kaumudi.H Congratulations ... I guess. I have no strong views on eyebrow threading.

user228700

No, me neither :-P Congratulations are out of order; that was just completely random information, really. It was the first time in my life doing it, and it was exceedingly painful.

John Rennie

@Kaumudi.H that's OK, I have plenty of spare laptops to send her. Now you begin to understand why I'm always buying laptops :-)

user228700

@JohnRennie :-) To serve the needy! That is, of course, one of the primary purposes of existence of the ~~vengeful~~ kindhearted Laptop Man!!

John Rennie

@Kaumudi.H don't eyebrows grow out in a couple of weeks? Your eyebrows will look great for two weeks then back to normal.

user228700

8:19 AM

@JohnRennie Yes, that is what will happen. I don't think I'll be going back :-P Like I said, I did it on a whim. All my friends who are girls do it quite regularly and this naturally lead me to wonder about my own eyebrows.

John Rennie

@Kaumudi.H I'll probably end up giving her the new one I just bought for my own use. Oh well, I'll just have to buy another :-)

user228700

It was painful too!!

John Rennie

I had my armpits waxed once and that was exceedingly painful. It gave me a new appreciation for the suffering women undergo in order to look more beautiful than other women.

user228700

@JohnRennie Ah, damn, wasn't that one particularly great?

user228700

@JohnRennie Your armpits?! Whatever for, may I ask?! :-o

John Rennie

8:20 AM

particularly great - that's why I'll give it to my niece :-)

user228700

Ah, haha, right :-) Generous and selfless as always, Mr. Laptop Man!

John Rennie

@Kaumudi.H it was when I worked for Unilever. The deodorants group wanted to culture the bacteria that grow in the armpit hair roots to study them. The idea was for volunteers to get their pits waxed and they would sample the roots for bacteria.

user228700

Oh, my!

user228700

What did they find out about those bacteria? x'D

John Rennie

It turned out the waxing process contaminated the roots with bacteria from the waxing strips so the whole thing was a waste of time.

Slereah

8:25 AM

did you volunteer?

Oh you did

Also hello!

user228700

@JohnRennie Oh, my God. That's quite sad, actually :-( I wouldn't have volunteered!

user228700

@Slereah Hi :-)

Slereah

Only 3 days left of that dumb web development project

Hopefully I can finish without killing everyone involved

Group projects truly are the worst

Especially when groups are formed under the idea of making groups "balanced"

ie putting good students (ie me) with bad students (the other dummies)

John Rennie

@Kaumudi.H I volunteered because I was curious to find out what having your pits waxed was like. I discovered it was painful :-)

Slereah

Were they silky smooth afterward

user228700

8:31 AM

@JohnRennie Geez!

user228700

Where was your common sense?! I would've ran away!

user228700

@Slereah Amen.

John Rennie

@Slereah smooth as a baby's arse

Apart from the scabs where the waxing had torn the skin and caused extensive bleeding

user228700

> extensive bleeding

user228700

Gosh :-(

John Rennie

8:34 AM

I exaggerate. But where each hair was pulled out it left a spot of blood and then a scab.

I'm told that if you're waxed regularly the hairs become thinner and pull out more easily so the waxing gets less painful with time.

Koolman

Hiii @JohnRennie

John Rennie

Morning :-)

Koolman

Morning

Can you help in C @JohnRennie

John Rennie

Well, I know C ...

Koolman

Till what time will you be here

John Rennie

8:48 AM

For about an hour

Avantgarde

-1

Q: How to avoid the last drop of pee (physics approach)

Since I was a child, I lived with a saying that my father taught me: "Well, son, you should know that the law of Archimede says that no matter how much you shake, the last drop will always go in your pants". Years later I became an engineer and every time I'm in a public bathroom and see how each...

what lol

Koolman

okay @JohnRennie

Can you please explain me what is testcases

Note: I am begginer

John Rennie

Slang term for testicles?

Koolman

actually it is written "First line contains the number of testcases"

John Rennie

I don't think test case has a specific meaning in programming. If you've written a program to do some calculation you'll probably want to test it with some input data for which you already know the answer. If so you'd probably call that a test case.

@Koolman I'd need to see the whole document to know what was meant by testcases in this context.

Koolman

8:56 AM

@JohnRennie

Balarka Sen

@SirCumference ahahah absolutely love my character

John Rennie

@Koolman Ah OK. In this case I think testcase means a set of initial conditions e.g. Arya and Winterfell's initial position. Presumably you're supposed to do some calcultion for each set of initial conditions.

Balarka Sen

shootin bikers y'all

@Avantgarde Damn son where'd you find this

Avantgarde

It was posted about an hour or so ago

Balarka Sen

I was posting a meme

It's a fantastic question

@Avantgarde hey you like hospin

or hopsin whatever the f his name is

Avantgarde

9:10 AM

Who's that?

No, never heard of him

Balarka Sen

Greatest rapper of all time

Avantgarde

Better be good. I'm pausing my metal

Balarka Sen

Watch it in full

It's damn good

Koolman

@JohnRennie should I send you the whole question

Avantgarde

Oh that guy puts reviews of underground metal and some rap albums (that I know of)

Balarka Sen

9:13 AM

he's the melon man

and that's his shitposting channel

the best teeth in the game

Avantgarde

the melon man?

Jasper

@BernardoMeurer You mean 'I've literally gone' instead.

Balarka Sen

yeah anthony fantano's nickname is "melon man"

Bernardo Meurer

@Jasper Whatever

Jasper

Hello @BalarkaSen. Were there any more flags last night?

Bernardo Meurer

9:17 AM

Flags?

Balarka Sen

lots of drama in the math room. i can't keep up with that shit

head mod Jon Ericson came in to warn a couple people

also s h o g

Koolman

@JohnRennie

Jasper

@BalarkaSen I see. Best to ignore some users completely.

@BernardoMeurer Flags in some other rooms.

Bernardo Meurer

Good idea

Avantgarde

Oh huh, interesting nick

The album I'm listening to now has this cover

Balarka Sen

9:23 AM

noice

Avantgarde

Do you watch horror? Any good one you know?

Balarka Sen

Man horror is my jam

what kind do you like

Jasper

@Avantgarde Yes. Watch Wrong Turn 1,2,3,4,5,6.

Avantgarde

Kinds? You mean supernatural, etc? I don't know much about the subgenres. Just give me something that you loved

Balarka Sen

@Avantgarde Alright, I can think of a couple I loved. Do you want to get super scary surrealist horror or watch a psychological downward spiral?

Avantgarde

9:26 AM

@Jasper It's good? Looks like one of those franchises, like Final Destination

@BalarkaSen The first one

Balarka Sen

@Avantgarde Eraserhead

Secret

Suppose people ignore the yuck factor, I wonder if biology se is a better home for this question

-1

Q: How to avoid the last drop of pee (physics approach)

Since I was a child, I lived with a saying that my father taught me: "Well, son, you should know that the law of Archimede says that no matter how much you shake, the last drop will always go in your pants". Years later I became an engineer and every time I'm in a public bathroom and see how each...

everyday-life flow medical-physics capillary-action

Jasper

@Avantgarde It's about deformed cannibals torturing and eating humans.

Avantgarde

@BalarkaSen Hm, I think either you've told me about it before, or I've seen that poster somewhere else before..

Balarka Sen

I don't think I have mentioned it to you before

It's by ya boi David Lynch

imo his best movie

Jasper

9:28 AM

@Secret WTF!

Avantgarde

@Jasper Okay well, I actually would like something to do with supernatural stuff

Jun 22 at 14:30, by Balarka Sen

In that genre, here's a few: Erasorhead, Videodrome, Naked Lunch, Dear Ringers, Hellraiser, Enemy.

Jasper

@Kaumudi.H Hi, I think it should be 'run' there instead. =D

Avantgarde

Yes you have @Balarka :P

damn, I have a lot pending lol

Balarka Sen

ah

Jasper

@Avantgarde Oh, then I think Final Destination 1,2,3,4,5 is good.

Balarka Sen

9:30 AM

those are all my favorites

absolutely loved the recent movie Enemy

Avantgarde

@Jasper I think I've seen parts of a few of those

I need to befriend someone with Netflix

Secret

Fun fact: While I am suceptible to the yuck factor, I can ignore some of them if necessary. Having said that, I still don't feel like eating fried bugs

Balarka Sen

@Avantgarde Netflix has none of the good stuff

Secret

Claim: Any yuck factor I cannot ignore are those that myself found yuck, but not necessary anyone else

Balarka Sen

sorry to break it to ya buddy

Secret

9:35 AM

The fact that sometimes politeness customs of the society is such a hindrance to some of my goals is one reason I sometimes disregard them

Jasper

@Secret Genuine kindness is more important than superficial politeness.

Secret

my goals being quest of knowledge related, lol

Avantgarde

@BalarkaSen :(

Still waiting for spotify to be here

Secret

@Jasper That is absolutely true, this is why I seldom act polite to most people and only people can tell me what my kindness are

I found polite mannerisms in some meetings very pointless and redundant

Jasper

@Secret I find handshakes extremely stupid. Besides, I have sweaty palms and don't like shaking hands.

Secret

9:38 AM

Well, there does exists advices that sweaty hands can avoid shaking hands

And for me, I just told other people I am on medication and thus I cannot drink alcohol

(Not that I ever liked the taste anyway)

Jasper

You just have to tell them you don't drink.

Avantgarde

How do people react to that?

Jasper

Alcohol tastes terrible.

Balarka Sen

@Avantgarde You can find Dead Ringers on youtube.

Fully available in high quality

A very good movie in my opinion.

Secret

They are quite understanding. Nowadays, most conferences have soft drinks to cater those who cannot use alcohol for socialisation

and my favourite being apple juice

Avantgarde

9:40 AM

@BalarkaSen Aw yes, found it. You made my Saturday

Jasper

@Secret When did conferences ever have alcohol?

Secret

Some large conference in science fields prepare a host of drinks and food for the participants

Jasper

@Secret Apples grow in the fields, so after drinking apple juice you can do field theory.

Avantgarde

@Secret Apple juice is pretty good

Balarka Sen

@Avantgarde This one, just to clarify

Avantgarde

9:42 AM

@BalarkaSen Yes, I got that one

Balarka Sen

Cool

Hm, I wonder if one can classify "Stalker" as horror. It is pretty terrifying :P

I think I have actually seen posters of it calling it a piece of Russian horror

Avantgarde

The plot description looks great

Balarka Sen

for which

Stalker?

Avantgarde

yes

John Rennie

@BalarkaSen the film of the Strugatsky's book?

Balarka Sen

9:57 AM

@Avantgarde This wonderful movie has been uploaded recently on youtube here with high quality.

Avantgarde

More than 2.5 hours long!

Balarka Sen

that shit's perspective-changing

@JohnRennie yeah but Tarkovsky said he actually deviated a lot from the Strugatsky novel

(I haven't read it, actually)

Avantgarde

Thank you! This is good. I guess, then, a couple of old movies would be there on youtube?

John Rennie

@BalarkaSen he must have. The book isn't horror in any sense. It's just a really good scifi book.

Balarka Sen

I suspect so

I enjoyed "It's Hard to be a God"

John Rennie

9:59 AM

Actually I wasn't so keen on that. To be honest "Roadside Picnic" is the only book of theirs I really liked.

Balarka Sen

@Avantgarde I suppose so!

Jasper

@Avantgarde Longest movie I watched is Titanic (1997), more than 3 hours.

Avantgarde

It was 3 hours long?

Balarka Sen

I think Tarkovsky's movies are getting reuploaded because of the recent demonstration of his 7 masterpieces on London

also yep they are a bit long

Avantgarde

Then you will love Devdas :P

Balarka Sen

10:01 AM

pls no

Jasper

@BalarkaSen Is it really about a God?

Balarka Sen

It's about Stalinian totalitarianism in a planet of intelligent beings that has stopped developing past their colonial age

@JohnRennie I need to read Roadside Picnic someday

Secret

[Some notes on time travel]
Actually, if you think about it carefully in a special relativity perspective of travelling to the future: The future that you will end up has to be the future that is resulted due to your sudden disappearance from the world during that time of absence. That is, even if backward time travel is impossible in physics, one can never reach the future that is resulted from the presence of themselves,

Unless: You get someone to replace your role at key events in the history, thus maintaining that future for you to reach

Koolman

@JohnRennie in that what is the use of constraints

John Rennie

@Koolman constraints? The question doesn't mention any constraints.

I have to go now. I may not be back until Sunday morning.

Koolman

10:09 AM

1 hour ago, by Koolman

@JohnRennie

Leaky Nun

10:25 AM

@Koolman "what is the use of constraints?"

well, to avoid your program from having large inputs?

Koolman

10:56 AM

@LeakyNun then how can we apply it to our program

Leaky Nun

you don't

they're just there to let you know the degree of optimization required

Koolman

ok

can you help me in a program

Leaky Nun

how?

Koolman

-2

Q: Graph programm in C

I want to write a code in which i want to know how much time is needed to move from one point to another . Input 1) First line(input) is showing the maximum time required to reach 2) Second line(second and third input) shows the intial position. 3)Third line(fourth and fifth input) shows ...

c

@LeakyNun this one

Leaky Nun

Show me the program you now have, after applying the corrections as suggested in the comments

use Ctrl+K to show a code

Koolman

11:01 AM

#include<stdio.h>
#include<stdlib.h>

int main()
{
int c,d,e,f,b,a;
scanf("%d",&a);
printf("\n");
scanf("%d",&b);
printf("\n");
scanf("%d",&c);
scanf("%d",&d);
printf("\n");
scanf("%d",&e);
scanf("%d",&f);
printf("\n");
int g,h,i,j;
scanf("%d",&g);
scanf("%d",&h);
scanf("%d",&i);
scanf("%d",&j);

int k,l,m,n,o;
e-c==k;
f-d==l;
if(k>=0&&l>=0)
{
m=k*h;
n=l*i;
}
else if(k<=0&&l>=0)
{
m=k*g;
n=l*i;
}
else if(k>=0&&l<=0)
{
m=k*h;
n=l*j;
}
else
{
m=k*g;
n=l*j;
}
o=m+n;
if(b>=o)
{
printf("\n %d",o);
}

@LeakyNun

Leaky Nun

press Ctrl+K.

@Koolman press Ctrl+K before sending your code.

Koolman

@LeakyNun it is coming like this only

Leaky Nun

then press Ctrl+K twice

paste your code to pastebin and send the link here

also, you haven't corrected the line e-c==k

Koolman

What is wrong in that

pastebin.com/BsUGFBWw

Leaky Nun

tell me what it is supposed to do

and why is there no indentation...

Koolman

11:11 AM

@LeakyNun it is just to make easier by introducing a new variable

Leaky Nun

@Koolman which variable?

Koolman

ohh should I use k = e - c

Leaky Nun

yes

Koolman

I am using this input of first test case

then why I am getting "Valar Codulis"

@LeakyNun

Leaky Nun

what did you get?

Koolman

11:18 AM

"Valar Codulis"

Leaky Nun

what should you get?

Koolman

1

pastebin.com/BKCS9vKb

@LeakyNun

Leaky Nun

because you should use = instead of ==.

Koolman

got it

Thanks a lot

@LeakyNun If I want to use second test case then should copy paste the previous test case or is there any other good method

Leaky Nun

you should use a for loop

Koolman

11:31 AM

you mean "for" loop

Leaky Nun

yes

Koolman

I should run for loop till where

I am starting it after scanf("%d",&a);

@LeakyNun

Mr. Xcoder

I smell C

Koolman

Yup

Leaky Nun

11:49 AM

@Koolman till the end

Koolman

i got that

but I Want to print the result simultaneously of the testcase

pastebin.com/JgTLBBF7

@LeakyNun for that what should I do

Secret

#include<stdio.h>
#include<stdlib.h>

int main()

{
int c,d,e,f,b,a;
scanf("%d",&a);
printf("\n");
int s;
for(s=1;s<=a;s++)
{

scanf("%d",&b);
printf("\n");
scanf("%d",&c);
scanf("%d",&d);
printf("\n");
scanf("%d",&e);
scanf("%d",&f);
printf("\n");
int g,h,i,j;
scanf("%d",&g);
scanf("%d",&h);
scanf("%d",&i);
scanf("%d",&j);

int k,l,m,n,o;
k=e-c;
l=f-d;
if(k>=0&&l>=0)
{
m=k*h;
n=l*i;
}
else if(k<=0&&l>=0)
{
m=k*g;
n=l*i;
}
else if(k>=0&&l<=0)
{
m=k*h;
n=l*j;
}
else
{
m=k*g;
n=l*j;
}
o=m+n;
if(b>=o)

int main()

{
int c,d,e,f,b,a;
scanf("%d",&a);
printf("\n");
int s;
for(s=1;s<=a;s++)
{

scanf("%d",&b);
printf("\n");
scanf("%d",&c);
scanf("%d",&d);
printf("\n");
scanf("%d",&e);
scanf("%d",&f);
printf("\n");
int g,h,i,j;
scanf("%d",&g);
scanf("%d",&h);
scanf("%d",&i);
scanf("%d",&j);

int k,l,m,n,o;
k=e-c;
l=f-d;
if(k>=0&&l>=0)
{
m=k*h;
n=l*i;
}
else if(k<=0&&l>=0)
{
m=k*g;
n=l*i;
}
else if(k>=0&&l<=0)
{
m=k*h;
n=l*j;
}
else
{
m=k*g;
n=l*j;
}
o=m+n;
if(b>=o)
{
printf("%d",o);

}
else
{
printf("Valar Codulis");

Koolman

what is this @Secret

Secret

int main()

{
int c,d,e,f,b,a;
scanf("%d",&a);
printf("\n");
int s;
for(s=1;s<=a;s++)
{

scanf("%d",&b);
printf("\n");
scanf("%d",&c);
scanf("%d",&d);
printf("\n");
scanf("%d",&e);
scanf("%d",&f);
printf("\n");
int g,h,i,j;
scanf("%d",&g);
scanf("%d",&h);
scanf("%d",&i);
scanf("%d",&j);

int k,l,m,n,o;
k=e-c;
l=f-d;
if(k>=0&&l>=0)
{
m=k*h;
n=l*i;
}
else if(k<=0&&l>=0)
{
m=k*g;
n=l*i;
}
else if(k>=0&&l<=0)
{
m=k*h;
n=l*j;
}
else
{
m=k*g;
n=l*j;
}
o=m+n;
if(b>=o)
{
printf("%d",o);

}
else
{
printf("Valar Codulis");

Koolman

I mean why you have send yhis

*this

Secret

12:00 PM

Testing...

ok, nvm, it is ok now

Koolman

@Secret can you help me in this

skullpatrol

please use the sandbox for tests :-)

Secret

I will NOT help you on anything that show no effort!

Koolman

I have made 95% program

what more effort you want

uhoh

12:22 PM

8

Q: The physics behind the Starshade

The Starshade is a space telescope with a large occulter that can fly off and block the light of a star so its telescope can picture the surrounding exoplanets: I sort of understand the optics behind its shape; the light that bleeds around the edges their waves c...

orbital-mechanics imaging exoplanet

bounty +100

expiring soon

Koolman

@heather can you help me in C

heather

@Koolman why me? did you just randomly ping me?

Koolman

I thought you know C thats why

if you are free you can help me

heather

what do you even want to do?

Koolman

I just to make a program

heather

12:37 PM

right, that does what?

Koolman

pastebin.com/JgTLBBF7 In this I want to show the output simultaneously of diifderent testcodes

heather

i'm not sure what that means

what testcodes?

Koolman

Means running the program two times

@heather

heather

what are you trying to output?

running the program two times to do what?

Koolman

-4

Q: Graph programm in C

I want to write a code in which i want to know how much time is needed to move from one point to another . Input 1) First line(input) is showing the maximum time required to reach 2) Second line(second and third input) shows the intial position. 3)Third line(fourth and fifth input) shows ...

c

This is the question

heather

12:50 PM

first, use standard good programming practice and name your variables something other than letters of the alphabet

have you made the edits to code as suggested in the answer?

Koolman

Yes I have edited them

Already posted the link

pastebin.com/JgTLBBF7

heather

you still didn't name your variables well

Koolman

That I will do next time , please solve my that problem

heather

no, i'm not going to just solve a problem where you haven't really put any effort in to make it understandable to others.

i've scrolled through the transcript and you've pinged a half-dozen people to "just solve the problem" for you.

Jasper

1:05 PM

@Koolman Maybe try your best and then post it as a question on the main site.

mathvc_

Hey guys! I have a very simple question I guess. I heard it is not allowed from quantum mechanics that three particles to be entangled. Is it right?

(Actually I saw in Susskind's lecture it leads to the AMPS paradox)

Anonymous

4

Q: three-particle quantum entanglement

So I know that two particles can be entangled in a quantum way, but is it possible that more than two particles be entangled in a quantum way? Most descriptions provide with two-particles cases, so I wonder. (It's hard to think of three particles entangled in spin, or so.)

quantum-mechanics quantum-field-theory quantum-entanglement

mathvc_

This is exactly what I saw before asking!

but it says it is possible

I again see in Maldacena talk and he said it is not allowed by quantum mechanics

Anonymous

Firewall (physics)

A black hole firewall is a hypothetical phenomenon where an observer falling into a black hole encounters high-energy quanta at (or near) the event horizon. The "firewall" phenomenon was proposed in 2012 by Ahmed Almheiri, Donald Marolf, Joseph Polchinski, and James Sully as a possible solution to an apparent inconsistency in black hole complementarity. The proposal is sometimes referred to as the AMPS firewall, an acronym for the names of the authors of the 2012 paper. The use of a firewall to resolve this inconsistency remains controversial, with high-energy physicists divided as to the solution...

Anonymous

@mathvc_ Could you quote Susskind ?

Anonymous

1:13 PM

I haven't read his lectures

mathvc_

@Blue Let me refer to JM because it's easier for me

Mauricio

@Blue I don't see why not.

mathvc_

Entanglement and Geometry | Juan Maldacena

►

from 7:00 to 7:30

Koolman

I got it FINALLY

mathvc_

"Since to have a triple entanglement, that doesn't seem to be reasonable lol"

Jasper

1:19 PM

@Koolman Well done. Sometimes all we need is a little bit more time.

Koolman

yeah

Mithrandir24601

@mathvc_ to be blunt, this has been observed, so personally, I wouldn't listen to lectures of anyone claiming this, unless they can prove you'd get something that looks exactly like it

mathvc_

I mean he said clearly that triple entanglement is forbidden by quantum mechanics

I heard it from Susskind's lecture too

So I guessed it is an obvious fact that I dont know

ACuriousMind

@mathvc_ I have no idea what Maldacena is talking about. Whatever is supposed to be forbidden there, it is not the simple possibility of three particles being entangled.

mathvc_

@ACuriousMind He was trying to clarify the AMPS paradox

ACuriousMind

1:25 PM

So? That still doesn't make the statement correct.

mathvc_

I don't know anything about it! I'm asking. You know why AMPS is a paradox!

ACuriousMind

In fact, I don't know what the AMPS paradox is - are you talking about the black hole information paradox, to which the AMPS firewall is supposed to be a solution?

Mithrandir24601

@mathvc_ you're missing the context - particles emitted from a black hole apparently can't be entangled with more than 1 other

mathvc_

@ACuriousMind yes

Secret

Actually, what does quantum monogamy actually mean, isn't that means 3 particles cannot be 100% entangled?

mathvc_

1:27 PM

@Mithrandir24601 apparently or fundamentally?

Secret

But we do have GZX states, so what is the rationale?

Mithrandir24601

@mathvc_ theoretically

ACuriousMind

@Secret It means that if entanglement between A and B is maximal (by some suitable measure of entanglement) and if A and B are qubits, then they are not entangled with anything else.

mathvc_

@Secret monogamy principle. yup that's my answer! I found it here btw physics.stackexchange.com/questions/218085/…

Secret

So how does 3 particle entanglement obey monogamy?

like the GZX states

ACuriousMind

1:30 PM

@Secret I do not understand the question.

Secret

Give me a sec when I dig the correct name...

ACuriousMind

@Mithrandir24601 Actually, that makes no sense to me. Hawking radiation is thermal, so it's a multipartite entangled mess of a state.

I mean, it being thermal is precisely the problem since it carries no information!

Secret

Greenberger–Horne–Zeilinger state

In physics, in the area of quantum information theory, a Greenberger–Horne–Zeilinger state is a certain type of entangled quantum state which involves at least three subsystems (particles). It was first studied by Daniel Greenberger, Michael Horne and Anton Zeilinger in 1989. Extremely non-classical properties of the state have been observed. == Definition == The GHZ state is an entangled quantum state of M > 2 subsystems. In the case of each of the subsystems being two-dimensional, that is for qubits, it reads | G H ...

@ACuriousMind That's a three qubit entangled state

ACuriousMind

If the particles emitted would be entangled/correlated in pairs and other curious ways, there would be information coming out and there would be no paradox

@Secret Yes, I know what a 3q entangled state looks like.

What is the question?

Mithrandir24601

@ACuriousMind I've never looked into it, but it apparently resolves some paradox about black holes

Secret

1:33 PM

@ACuriousMind How does that not violate monogamy since you have more than two qubits entangled (maximally?)

ACuriousMind

@Secret See the question mark behind "maximally"?

Please come back to ask this question after you have actually computed an entanglement measure for this state and the substates for two particles.

It's not entangled maximally, so it has nothing to do with monogamy.

@Mithrandir24601 Sure, if you claim that the radiation coming out is not actualyl thermal but carries information, then that will resolve the paradox alright! :P

::sighs:: This always happens when I talk about BH information with anyone - lots of very smart people have said lots of stuff about it that just seems so evidently silly to me. And it's all always weird handwaving :P

Mithrandir24601

@ACuriousMind very true - it's been a while since I've done BH stuff, so I've forgotten loads of it :/

Avantgarde

@Mithrandir24601 The black hole information paradox still lives on. There's no resolution yet, though things have gotten sharper over the years, especially the last couple of years

Oh, I see I missed a nice discussion here

mathvc_

@ACuriousMind do you know what is the topic I can study about quantum entanglement?

quantum information? or computation?!

ACuriousMind

I'm afraid I don't understand the question - there are probably many topics you can study that involve quantum entanglement

mathvc_

1:48 PM

okay! here I have to be accurate! I don't know anything about quantum entanglement. Do you know good books on it?

ACuriousMind

Well, do you know quantum mechanics?

mathvc_

yup

i'm a math student actually so I know a bit about quantum mechanics

Mike Doonsebury

Hey, I seem to recall that Stack Exchange had a board where people could post theories and get feedback. Is that still around or did I dream it up?

ACuriousMind

@mathvc_ As in, the formalism? Hilbert spaces, operators, expectation values and all that jazz? Because if you do, "entanglement" is not very mysterious - it's just a name for states that are not the tensor product of two states of a subsystem.

@MikeDoonsebury I'm 99.99% certain you dreamt that one up ;)

mathvc_

@ACuriousMind yup! But I'm pretty sure there are very good books specially for quantum entanglement. I'm not familiar with physics books and topics that's why i'm asking

ACuriousMind

1:54 PM

Well, I'm actually not really familiar with many books either, so I'm of no help to you :/

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