The h Bar - 2019-08-06 (page 1 of 3)

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enumaris

00:13

whoop, it's a driver power state error

blue screen of death lol

danielunderwood

00:34

Are you using GeForce Experience? It supposedly handles the driver install/updates for you. You may also want to check your power mode in windows. I think a lot of laptops with a gaming GPU will also have an integrated GPU that it'll switch between depending on the power mode

enumaris

00:49

I have some nvidia drivers but I don't really deal with it...

I don't see where in the power plan I can switch GPU or CPU

Ryan Unger

get geforce experience to make sure you have the right drivers

enumaris

apparently I do have it

ah there's an additional option in blender to use CUDA or OpenGL...or None...I was on None...so it was trying to use the GPU without CUDA? How's that work...

with the CUDA enabled it's somewhat faster

but...not like uber fast...

vzn

01:26

@JohnRennie had some time to further follow up. delightfully the entire 546p book is downloadable for free. considered your assertion bold/ improbable and its easily refuted on simple skim of TOC. eg see p222. also note Bohm referenced madelung fluid in one of his papers, although this seems largely overlooked even by his followers/ descendants. as already noted in my blog the emergent QM paradigm is closely aligned/ coupled with the fluid paradigm & think its getting stronger all the time.

nitsua60

@JNat Thank you very much! It is a very fair and rational explanation. (Please, don't forget the Space SE, Astronomy SE and Engineering SE, too.) — peterh Aug 2 at 12:56

(and following comments)

enumaris

01:41

I should model Thanos...

at least I should model something other than what was in the tutorial lol

Skyler

thanos should model your data, i bet he's pretty good at cross validation

enumaris

02:05

but he's snap away half my data

then I can't train...

1 hour later…

Sir Cumference

03:05

@nitsua60 Hmm, not sure whether to interpret that as "Astro, etc. is not 'healthy' enough to graduate yet" or "we'll get to them soon enough"

nitsua60

@SirCumference Yeah, I'm not sure either. If I had to wager I'd throw money on the side of "we'll get to them soon enough," but I can't point to anything making me say that: just the healthy-looking metrics on those sites and Catija's years-long advocacy for "small" sites.

Ryan Unger

03:57

@Slereah arxiv.org/abs/1908.01712

1 hour later…

Slereah

05:23

morgen

3 hours later…

PM 2Ring

08:07

@JMac pittsburghjoe, the negative quantum spacetime guy, is back. physics.stackexchange.com/questions/495420/… I assume he's referring to nature.com/articles/d41586-018-07848-2

Slereah

why so negative

a positive quantum spacetime sounds more cheerful

user129412

If I consider some small conductor (an island), isolated from the environment, it'll well described by a single charge state. This is in contrast to an island connected to a lead by a tunnel junction with large conductance, where charge fluctuates quite heavily among multiple charge states. What kind of term could one use to describe such a system? Is it fair to say that charge is localized on the island, or does that imply more of a spatial concept rather than being in a single charge state?

Or maybe a shorter way of stating it, is there a term that can be used to denote that a system is very narrow in the charge basis? Say a cooper pair box versus a transmon qubit

Slereah

@ACuriousMind

I need to talk about

quantum hamburgers

Secret

08:23

nationalgeographic.com/science/2019/07/…

I cannot work out where the head of the lizard is from the fossil. It just looks like a pile of criss crossing bone mesh to me

Slereah

@bolbteppa I guess it's a "making sure this idea actually works and isn't just a coordinate artefact" thing

cf Schwarzschild/Rindler horizons

Ryder Rude

08:50

What does a Black Hole do to the thing it swallows?

Slereah

Depends what you mean by "black hole"

John Rennie

@RyderRude hi Ryder :-)

Ryder Rude

Hey John

Slereah

This is where I argue that "black hole" is such a wide term that it's basically meaningless to discuss anything generic about black holes

John Rennie

The problem is that nothing inside the event horizon can influence anything outside the event horizon.

When we measure properties of e.g. a DNA molecule that means the properties of the molecule influence our measuring equipment.

Slereah

08:52

are we talking a Schwarzschild metric or some weird Oppenheimer-Snyder-Vaidya solution

Ryder Rude

Maybe I'll need to read up on event horizon

Slereah

@JohnRennie Not a problem at all if you just send the observer to the black hole

although he won't like it

John Rennie

@RyderRude Hmm, OK, you will need a bit of background for this to make sense.

Slereah

but then again the singularity is spacelike so it's just that the observer will cease to exist after a while

Ryder Rude

Can we trace back even pure mass energy conversions
in a nuclear bomb back to the pre-explosion state?

kyle campbell

08:53

Schwarzschild would be useless for that purpose

Slereah

@RyderRude if you don't assume quantum mechanics, sure

but with QM, not really

Schwarzschild's a fine metric but it's also quite possibly the least realistic black holes around

John Rennie

@RyderRude in principle yes.

Slereah

It always feels a bit weird that we discuss black hole stuff with it

kyle campbell

I don't think it would be useful for that calculation specifically

or at least you could pick a better one

John Rennie

Basically all the equations used in physics, including QM, are time symmetric. So we can start with an end state and trace it back to earlier times.

Ryder Rude

08:55

Does this mean Black Hole obeys different physical laws than QM?

John Rennie

@RyderRude kind of ...

Slereah

@JohnRennie Not sure I can agree there!

QFT is specifically defined with a preferred time direction

John Rennie

@RyderRude Black holes are a prediction of general relativity, and right now we don't know how quantum mechanics fits with general relativity.

Slereah

Also we can do that with states but we can't measure states

Ryder Rude

Does general relativity allow time to be traced back?

John Rennie

08:57

QM is consistent with special relativity - linking the two gives us quantum field theory. But making QM consistent with general relativity is proving hard to do.

Slereah

Well

John Rennie

@RyderRude time is weird in GR i.e. what we instinctively mean by the word time gets confused.

Slereah

It's not that hard to do

But it's hard to know which one is correct

We kinda lack experimental data, too

kyle campbell

I'd argue that's the same thing

Ryder Rude

I know that time depends on reference frame. But anyone in their reference can trace back time if given all the data, right}?

John Rennie

09:00

@RyderRude but there is a fundamental problem that you can't look at a black hole and figure out what's inside it i.e. no matter how good your measurements the stuff inside the horizon is inaccessible.

Ryder Rude

And the swallowed things go inside of the horizon?

kyle campbell

@RyderRude en.wikipedia.org/wiki/Firewall_(physics) this might be of interest to you

John Rennie

@RyderRude yes.

Slereah

@RyderRude welcome to the wonderful world of the Cauchy problem in general relativity

Ryder Rude

Maybe Hawking Radiation can be traced back

All the swallowed stuff becomes Hawking Radiation?

Slereah

09:03

This is where I slide in again

Ryder Rude

Hawking Radiation is energy. And energy can be traced back to matter

Slereah

What we are discussing here is the Schwarzschild metric.

The Schwarzschild metric is static

it does not change

If we want to discuss an actual black hole losing mass, that is a very different matter

John Rennie

@RyderRude Hawking radiation is what we call thermal radiation. That means it contains only limited information.

Specifically it cannot contain all the information of the stuff that fell in.

So the information coming out in the radiation has to be less than the information that fell in.

And that means information is inevitably lost.

Ryder Rude

So, basically, things go inside the black hole. I formation about them can't be accessed from the outside while they 're inside. Inside, they get converted to Hawking Radiation, which is a 'limited information's Radiation so can't be traced baxk

John Rennie

Yes

Ryder Rude

09:06

Is Hawking Radiation an electromagnetic wavw

John Rennie

Not necessarily.

Ryder Rude

What makes it special

John Rennie

Anything can be emitted as Hawking radiation.

Ryder Rude

It's pure energy

John Rennie

No.

Ryder Rude

09:07

Is it matter too}?

Is it hot matter?

John Rennie

All particles, electrons, photons, Higgs bosons, etc are described by quantum fields.

Basically what we call a particle is a little packet of energy ina quantum field.

PM 2Ring

Another problem with Hawking radiation is that to properly calculate it we need a quantum gravity theory. So we don't really know if it exists or not. And of course (if it exists) it's very weak and cold, so even if we could send a probe to a black hole it'd be really hard to detect the Hawking radiation.

John Rennie

What Hawking showed is that the energy of the black hole can be transferred into quantum fields, where it appears as particles. That's why he predicts particles will be emitted froma black hole, and that's what Hawking radiation is.

Ryder Rude

Hot particles with thermal energy

Vibrating particles

John Rennie

For large black holes the energy emitted is very, very small, and that means only very low energy particles can be emitted. Since the mass of a particle counts towards its energy that means only massless particles will be emitted.

PM 2Ring

09:10

But we do expect that most of the Hawking radiation will be emitted as photons, until the very late stages of evaporation, when things heat up a bit.

John Rennie

And the only massless particle that can travel far enough for us to see it is a photon. So in practice everyday black holes will only emit photons.

Ryder Rude

Do photos normally allow information to be traced back?

John Rennie

Yes

Ryder Rude

I mean photons not emitted from black holes

So what is special about black hole photons?

John Rennie

What's special is the emission process.

A photon from e.g. a light bulb comes from a discrete event on the filament of the light bulb and could in principle be traced back to it

But the photons in Hawking radiation are emitted from a broad region of space around the black hole.

Ryder Rude

09:13

Maybe the processes inside the event horizon isn't like normal physics that we know

Slereah

As you may recall

Black holes only have three sort of informations you can extract from them

Mass, angular momentum and charge

And this is reflected in the Hawking radiation

Ryder Rude

Some process inside the event horizon converts mass to Hawking radiation

Slereah

The flux of Hawking radiation depends on the mass of the black hole

John Rennie

@RyderRude have a look at:

26

Q: An explanation of Hawking Radiation

Could someone please provide an explanation for the origin of Hawking Radiation? (Ideally someone who I have been speaking with on the h-bar) Any advanced maths beyond basic calculus will most probably leave me at a loss, though I do not mind a challenge! Please assume little prior knowledge, as...

black-holes vacuum hawking-radiation qft-in-curved-spacetime unruh-effect

Ryder Rude

Is it expected to be a normal process?

Slereah

09:15

Their total angular momentum depends on the black hole's angular momentum

And the proportions of the charges emitted as well

ie a positively charged black hole emits more positively charged particles

all other previous informations about the matter that fell in is lost

Ryder Rude

Do we know the process by which matter is converted to Hawking Radiation inside black holes

Slereah

Well that's how we derived it, yes

PM 2Ring

@RyderRude We have no reason to expect that normal physics breaks down inside the event horizon, until you get really close to the centre of the black hole, where we expect quantum gravity effects to become significant. OTOH, nothing inside the event horizon can ever have a causal effect on stuff outside the event horizon.

Slereah

It depends which theory you use, of course, but it's generally a process called gravitational squeezing

Where gravitational fields act upon the quantum state around the black hole

which causes it to radiate

John Rennie

@RyderRude we currently describe Hawking radiation using an approximation because the exact details aren't known. Within the bounds of this approximation the process is well understood.

PM 2Ring

09:18

@RyderRude Hawking radiation is produced outside the event horizon.

Ryder Rude

What exactly happens inside which is causing information loss

John Rennie

@RyderRude NB the radiation comes from outside the horizon not inside.

PM 2Ring

It's also helpful to think of the mass of a BH residing outside the event horizon, in the spacetime curvature. As stuff falls into the BH, it modifies that curvature, upto the point that it crosses the horizon, after which it can no longer affect the outer universe. See math.ucr.edu/home/baez/physics/Relativity/BlackHoles/…

John Rennie

@RyderRude the bottom line is that the more closely you look at all this the weirder it becomes :-)

To understand what's going on you have to learn general relativity. There's a limit to how well it can be explained in popular science terms.

Ryder Rude

Yeah,

I don't even understand special relativity

Learning the math would make things more clear than English explanations

Thanks

John Rennie

09:28

You're welcome. The chat room exists for discussions like this so feel free to ask questions here any time.

kyle campbell

@RyderRude The math in special relativity tends to be much easier going, so that's a great place to start.

Slereah

Honestly

Understanding Hawking radiation is fairly advanced stuff

You probably shouldn't worry about it too much until you've learned GR and QFT

Although here's a dirty secret

There's nothing classically to prevent a black hole from losing mass

It's the same process by which Hawking radiation works

Violation of the strong energy condition

Basically negative energy radiates inwards

Of course not really a lot of process with negative energy classically, but math-wise it's the same idea

PM 2Ring

@RyderRude You might enjoy Greg Egan's Foundations articles on relativity & QM. "These articles are for the interested lay reader. No prior knowledge of mathematics beyond high school algebra and geometry is needed." They aim much higher than typical pop-sci articles, since Egan doesn't shy away from the mathematics, but he tries to keep the maths from getting too tricky.

1 hour later…

Emilio Pisanty

10:46

@Semiclassical You around?

I'm struggling with an integral

$$\int_{-\infty}^\infty \frac{e^{-p^2/\Gamma^2}}{p^2 +\kappa^2} e^{ipx}\mathrm dp$$

looks eminently doable, right?

but mma is struggling and it's nowhere that I can find on G&R

numerical integration suggests a shape not unlike $\exp(-\sqrt{1+x^2})$

but I'd like a better argument than "that's roughly what it looks like"

Aaron Stevens

11:31

Are we allowed to vote to close a question because the OP seems to not want to listen to what anyone has to say? Haha

Emilio Pisanty

@AaronStevens downvote and move on. Or, if there is a suitable duplicate target, vote to close, downvote, and move on.

Aaron Stevens

@EmilioPisanty Yeah I know. Just messing around :)

Emilio Pisanty

11:48

or, in other words, spend the time looking for duplicates instead of fighting with OP

particularly when the question is a standard misconception that's bound to have appeared before

;-)

skullpetrol

link please

Aaron Stevens

-5

Q: Why does everyone seem to think that moving clock appear to tick slower?

I'm getting interested in special relativity and almost all people and explanations about the subject I found on the internet seem to think that when A and B would be in relative motion, they would both observe the other's clock tick slower than their own. However what I found about this is follo...

special-relativity reference-frames time

skullpetrol

Thanks

Aaron Stevens

@EmilioPisanty Yeah I put in my answer and replied to a comment and I'm ready to move on now that I have realized the OP won't budge. Certainly didn't start fighting with the OP like others did haha. Although I will admit that I should have looked for the obvious duplicate. I guess I wanted to clear the specific interpretation of what they quoted.

Emilio Pisanty

@skullpetrol physics.stackexchange.com/users/179151/… easy to dig ;-)

skullpetrol

11:57

:-)

Emilio Pisanty

@Dale The time dilation has nothing to do with simultaneity. It is a physical effect on the travelling object and has casual impacts for both observers, unlike relativity of simultaneity which has no casual impact on anything. Oh and the clock you are passing by are considered to be at distance 0. Thats why they are on the tracks. These simplifications are the essence of the thought experiment. — Katz389 15 mins ago

but yeah, I can see how this type of thing would rub some the wrong way

Sebastiano

@EmilioPisanty Thank you very much for your help for my question(s).

Emilio Pisanty

@Sebastiano which questions were these?

Sebastiano

@tpg2114 @EmilioPisanty and (G.Smith: I have not a ping). Good morning: I have much appreciated your help. I have edited my question on commutators. In fact I have deleted the image and myself I have written in English language without a translate.

@EmilioPisanty This:

How to understand commutation operations in quantum mechanics?

0

Q: How to understand commutation operations in quantum mechanics?

With all honesty I find myself in difficulty to understand how the rules of switching in quantum mechanics work. I need these to understand and to prove the Heisemberg uncertainty principle. For example, with the rules of commutation, I would like to prove (myself) that $$\Delta p_y \cdot\Delta...

quantum-mechanics homework-and-exercises heisenberg-uncertainty-principle differentiation commutator

Emilio Pisanty

@Sebastiano that one is still totally unclear to me as to what you're actually asking

(not that I can recall having seen it earlier)

Sebastiano

12:07

@EmilioPisanty Please, what is the question?

Emilio Pisanty

@Sebastiano what do you mean?

Sebastiano

@EmilioPisanty I thought that one my question is unclear.

Emilio Pisanty

@Sebastiano Sorry, you're speaking in ungrammatical English, and I have no idea what you're trying to say.

In my opinion, this question should be closed as Unclear What You're Asking, until you can suitably clarify the text of the question.

Sebastiano

@EmilioPisanty I thought you were asking me that one of my questions wasn't clear. All the answers given are clear and exhaustive.

Emilio Pisanty

That's just my opinion, though.

@Sebastiano The presence and quality of answers is ultimately irrelevant to whether questions are on topic. The question's text should stand on its own.

2

Sebastiano

12:12

For me the question is clear :( and the answers are also clear.

Aaron Stevens

@Sebastiano FWIW I voted to close for the same reason a while ago

Emilio Pisanty

@Sebastiano I am giving you feedback about your post. You're obviously free to disregard feedback at any given time.

It could well be that my opinion is isolated and few others agree, in which case, go right on.

Sebastiano

@AaronStevens Good morning. I simply wanted to understand the rule of operation of the commutators so that I could prove myself the Heisemberg principle of indetermination.

Emilio Pisanty

It could also be that others have a similar opinion and will vote accordingly

in which case, disregarding feedback will have the obvious negative consequences for the post itself.

@Sebastiano It's no use trying to explain separately from the post.

Spend your time and energy editing the post itself.

Sebastiano

@EmilioPisanty ok. :-) thank you very much.

Emilio Pisanty

12:16

Communication is a multi-person process. You need to transfer what is inside your head to other people, and if other people are telling you that the text is unclear, it's because the communication process has failed.

saying "but it's clear to me" is essentially useless ─ it's extremely uncommon that, as the writer of a text, you'll be able to really read what the text actually says instead of substituting in what you wanted to write in the first place

particularly in languages where you're not fully fluent

if other people tell you that the text is unclear, and particularly if those people are in your intended audience, then take heed.

skullpetrol

btw @Sebastiano what is your first language?

Sebastiano

12:40

@skullpetrol Hi, Italian language.

ACuriousMind

@Slereah what hamburgers?

(caveat: I'm hungover and not likely to contribute anything useful for a few hours :P )

skullpetrol

must have been a good concert

ACuriousMind

What concert?

skullpetrol

the heavy metal one

(to be still hung over)

ACuriousMind

That...has nothing to do with the reason I'm hungover today

skullpetrol

12:48

oh

@Sebastiano the two regulars in this room could help you

Slereah

@ACuriousMind Sober up first you lech

ACuriousMind

never!

Slereah

a serious math person would only do amphetamines

skullpetrol

13:03

like Erdős?

Slereah

yes

we can only hope to be like Erdös

Tho I have never actually used any of his theorems

skullpetrol

so what does that make your Erdős number

Slereah

Never wrote a paper with anyone so far

so $\infty$

I did write my master thesis under the benevolence of Andrei Smilga

Not sure what his Erdos number is

skullpetrol

hmmm, sounds like something to look into

Slereah

He's not in the list of people with Erdos number 2

So at least 3

Maybe I should find one of the fossils with Erdos number 1 and write a paper with him

Come on grampa, we're writing a paper

skullpetrol

13:11

:D

Slereah

"There's a mathematician in Mexico named Florian Luca who seems to have been the last person to earn an Erdős number 1, through a paper published in 2007."

skullpetrol

how about an imaginary Erdős number

Slereah

I can imagine being Paul Erdos

So I have Erdos number $i0 = 0$

Loong

I wonder if I still have time to go shoot a short film with Kevin Bacon.

tpg2114

Sweet, I have an Erdos number of 6. Not bad for an aerospace engineer...

Slereah

13:21

I need to find some GR guy with a good Erdos number

tpg2114

I'm closer to Erdos than to my own brother... But my brother is closer to Erdos -- he has a 4.

Slereah

Geroch has an Erdos number of 4

tpg2114

Although he's actually a mathematician, so I guess that's somewhat expected

Loong

> any two people on Earth are six or fewer acquaintance links apart

Slereah

But Choquet-Bruhat has a number of 3!

tpg2114

13:24

(my brother that is)

Slereah

Time to go to miss Bruhat and hammer out a paper

tpg2114

@Loong The Oakland project says most have an Erdos of at most 8, with a few exceeding that

Slereah

Matt Visser also has 4

skullpetrol

Imaginary Erdős Number - Numberphile

tpg2114

And somehow I'm 7 away from my own brother in co-authors :)

Slereah

13:25

Guess who else has a 4

It's Lubos Motl!

I'm gonna propose a paper to Motl

skullpetrol

-__-

Slereah

It's called why LQG is wrong and string theory is great

Also the Copenhagen interpretation is the only one

Valter Moretti is also at 4

many such cases

John Rennie is unknown of the Erdosifier, though

For shame

Same with @EmilioPisanty

No paper on the toothpaste interpretation of spacetime

I guess I could write a paper on some path integral for polymer stuff with @JohnRennie

PM 2Ring

14:00

Danica McKellar also has an Erdős number of 4, Natalie Portman has a 5. Danica could easily bump her number to 3 by collaborating with her old topology teacher, Terrence Tao.

bolbteppa

Is a 5 or 6 good

Slereah

is that what u have

bolbteppa

Landau has a 5

Ryan Unger

14:19

@Slereah Schoen and Yau

Slereah

I'd better hurry, Schoen's 68

Ryan Unger

Just prove the spacetime Penrose inequality

Slereah

bit ambitious

Ryan Unger

Rick is an ambitious guy

Slereah

Rigorous path integral stuff is a tad annoying because there's kind of two sides

There's the everything is abstract measure theory side, and the everything is stochastic process side

And it's not immediatly obvious how the two connect

Gotta do the translation

Sebastiano

14:54

@Semiclassical Hi and good afternoon.

Semiclassical

hi

Sebastiano

Excuse me can you see my question on meta, please?

0

Q: I still don't understand how Physics.SE operates

In these years I'm always trying to understand how to write well the questions. My effort is obvious, but it is not always rewarded. My questions are about Physics, which are closely linked to Mathematics. I also signed up for Mathematics.SE. and some users on mathematics questions related to Phy...

discussion support questions down-votes

It is normal the answer?

@user212860 Hi, :)

Semiclassical

I've only seen that one question of yours, so I really have no insight on your questions as a whole

Sebastiano

You are the user who answered some of my questions. Thanks again.

Semiclassical

So I can't really provide much help on the meta question. That said

user212860

14:58

Any books, papers or any other material that you can recommend for topics dealt with in the following lecture: youtube.com/watch?v=vzjbRhYjELo&feature=youtu.be

Sebastiano

I'm still wondering if respect still exists

Semiclassical

the question you started with was "Why is X true" when, upon investigation, the question turned out to really be "how does this derivation work?"

user212860

its on strings, harmonic oscillators, Riemann zeta function, the Dedekind eta and how they relate to each other

Semiclassical

and I think it's not at all surprising that people are going to get frustrated, when you insist on the former for so long

(the language barrier makes things difficult as well, though I don't think that's definitive)

ACuriousMind

@Sebastiano The answerer is giving you some valuable, if blunt, advice. You would do well to heed it.

3

Sebastiano

15:02

Respect must never be lacking.

user212860

@Sebastiano Nobody has to respect each other

This website does not exist for respect and love

it is solely for physics and answering questions

Ask questions, answer questions and move on with your day

Semiclassical

well, there is a level of respect which is demanded of users---hence the "be nice" policy

user212860

You do not have to be nice

just dont be rude

Sebastiano

Stop stop stop is respect? "This webpage operates in English, and if that does not work for you, you'll have to find some Italian physics community somewhere online." Is this respect?

user212860

First of all respect is not countable

Second of it is not respect

it is just a human talking

ACuriousMind

15:06

@Sebastiano That's just a fact. We're sorry, but the language of this site is English, and we do expect all users to communicate in intellegible (not perfect!) English.

Semiclassical

I disagree with that sentiment, but I don't find it inherently disrespectful.

user212860

i cant see anything rude with what is inside the quotation marks

Sebastiano

Okay, I'm not writing anything anymore. :-) I edit my questions.

user212860

@Sebastiano this is just pure honesty

And I believe it is more useful than being nice and euphemistic.

Semiclassical

@ACuriousMind the word 'intelligible' in there is key. There's limits on how useful anyone on this site can be with a language barrier in the way

ACuriousMind

15:07

@user212860 Do I have to watch the whole lecture to be able to tell what it's about? The title is not terrible descriptive :P

Sebastiano

Honesty is also politeness, knowing how to write and not expel users.

user212860

@ACuriousMind its on strings, harmonic oscillators, Riemann zeta function, the Dedekind eta and how they relate to each other

i should have sent the two parts as a single message :D

but it is a very good lecture

I know where I can read about the Riemann zeta function, string theory, the partition function

But I was wondering if there were any material which covered the mentioned subjects as a whole

ACuriousMind

I don't think you'll find a single resource that covers everything

user212860

Not a single book of 10^4 pages

ACuriousMind

off the top of my head, terrytao.wordpress.com/2010/04/10/… is an excellent post if you want to understand the $1 +2 +3 +4 +\dots$ business

user212860

15:10

but perhaps a monograph or an expository article

ACuriousMind

but it doesn't cover anything else

user212860

@ACuriousMind I do believe I understand that

Semiclassical

@EmilioPisanty I'll check it out

i'm surprised G&R doesn't have it, though I'm less surprised about mathematica

bolbteppa

@user212860 his 'this weeks finds' discusses this stuff all over the place

user212860

@bolbteppa I will check it out

Emilio Pisanty

15:33

@Slereah link?

last I checked I had an Erdos number of ~6

user image

there it is

I severely doubt your erdosifying skills, @Slereah

though tbh I also severely doubt the accuracy of that erdosifier

seeing as how it only catches my first paper ever, and doesn't account for any of the papers from my PhD

or on second thought, maybe not, it does catch my PhD supervisor and my current PI, both at Erdos number 4

Emilio Pisanty

15:50

@Sebastiano There's a difference between blunt and disrespectful. However blunt, the answer you linked to is firmly on the respectful side of the line.

2

Slereah

@EmilioPisanty guess I typed in the wrong name

Emilio Pisanty

@Slereah it explicitly suggests LastName, Initial, and that works just fine =P

Slereah

Hey @EmilioPisanty

Wanna write a paper together

Emilio Pisanty

what I'd like to be able to get is the full set of length=5 chains

I suspect there's nicer ones out there between me and Erdos

Ryan Unger

I don't think mathscinet has every physics paper though

Slereah

15:52

Well there is certainly Lubos Motl

and Valter Moretti

Emilio Pisanty

@Slereah I suggested this earlier and you blew us off =P

@RyanUnger I strongly suspect mathscinet is missing significant chunks of the physics literature

Slereah

@EmilioPisanty Alas I don't know much about quantum optics

Ryan Unger

@EmilioPisanty my hint is that Hawking has only 3k citations according to them

whereas mathematicians of similar fame have 13k+

Barry Simon, JP Serre, Neil Trudinger, Tao, ...

Emilio Pisanty

@RyanUnger what's he got on WoS?

Ryan Unger

I'm a mathematician, I only use mathscinet :P

Emilio Pisanty

15:56

well, just going from the first page of search results on google scholar, he should have some 50k+ citations

say, is journals.aps.org/prd/abstract/10.1103/PhysRevD.28.2960 listed in mathscinet?

Ryan Unger

doesn't appear to be

oh no it is

Emilio Pisanty

what number of citations does it give it?

Ryan Unger

96

Emilio Pisanty

lolz

no

try 1.5k

Ryan Unger

where are all these coming from

Emilio Pisanty

16:04

physics =P

Ryan Unger

are 1.4k from vixra or something

the question is which physics journals are not grabbed by mathscinet

Emilio Pisanty

the PRD site lists 1.4k with ~450 coming from PRD, 183 from Class Quantum Grav., 119 from Phys Lett B, and then a smattering of few-tens journals

Ryan Unger

that's weird

mathscinet has class quant grav of course

Emilio Pisanty

which means that it's inconsistent for any database to cite under 450 citations

Ryan Unger

yeah the paper is PRD

Emilio Pisanty

16:07

unless they only grab partial archives

in which case... well, that's one useless database, innit

Ryan Unger

@EmilioPisanty hmm let's try a math paper

maybe mathscinet is missing math papers

Emilio Pisanty

@RyanUnger maybe mathscinet is actually useless, and mathematicians just haven't realized

Ryan Unger

try projecteuclid.org/euclid.ajm/1154098947

Emilio Pisanty

(just saying)

Ryan Unger

129 citations on mathscinet

@EmilioPisanty well I've never not found a paper that I was actually looking for

Semiclassical

16:52

@EmilioPisanty wouldn't the convolution theorem work for that integral, actually?

both e^(-p^2/Gamma^2) and 1/(p^2+kappa^2) have nice Fourier transforms

the result from the convolution theorem isn't nice but it isn't horrible either

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