The h Bar

Secret

00:09

3 hours ago, by Balarka Sen

I'm thinking, eg, how easy it is to blur the boundaries between science vs pseudoscience in social science in contrast to mathematics

Very true, especially for logic, pseudo logic will be spotted almostly instantly when you made a mistake with quantifiers

One problem of pseudoscience, is its models lack details to allow them to be testable

SigmaAlpha

01:34

Hi, I was hoping someone might be able to help me understand the following statement:

"At a point p of a manifold M, a metric g has a unique signature, sig(g)=(p,n-p). Since, in terms of a chart, the components g_{ab} are continuous and since the matrix of components is invertible at each point, it follows that there is some open set O in M containing p such that sig(g)=(p,n-p) at each point in O."

I understand the first part: that the metric has a unique signature at a point follows from Sylvesters theorem. But I don't understand the logic leading to the second conclusion

Sir Cumference

@Slereah How'd you upload a vector graphic?

vzn

03:01

@Secret "lack details to allow testing"? lol, what about impracticality or inaccessibility of testing, like, oh, say, string theory? extremely high energy particles? theories of black holes, or the big bang? dark matter/ energy? etc? :P

vzn

03:44

re kuhnian paradigm shifts also in math, it is not widely accepted/ debated (compared to other fields), but there are many academics who take it seriously and not hard to find a few refs via googling. heres one for this audience-- university senior prj with many refs. (and who else is working on one around here?)

Paradigms and Mathematics: A Creative Perspective / shives 2012 MAA History of Mathematics student paper contest winner maa.org/press/periodicals/convergence/…

ps kuhnian paradigm shift(s) + demarcation problem intimately intertwined...

Secret

04:17

snopes.com/fact-check/karl-marx-banknote-released-germany

Zero euro

@vzn it is a complicated topic. As you may aware, string theory is also quite shaky nowadays given how superstmmetric particles still failed to show up. But these models at least proposed a way to test them, thus they are testable in principle (even though it is borderline metaphysics and mathematics). Pseudosciences don't even bother doing that, which is why they are often said as not even wrong

Secret

04:42

red pill blue pill -----> user list

Dawood ibn Kareem

05:36

@Blue You overran your buffer, because strcat includes a terminating zero. So no, your C code is NOT OK.

Secret

06:07

Should Space be Privatized? | Space Time

►

Some rocket science and economics

Mockingbird360

06:20

Hello, guys. Can anyone tell me what universities or research institutions are doing great research on topological condensed matter physics

Anonymous

@DawoodibnKareem Yeah I know. I wrote that 20 initially without thinking much because I was in a hurry.

Dawood ibn Kareem

06:49

31

Q: Does the International Math Olympiad help research mathematics?

I was reading a note of Hojoo Lee on inequality which is written for International Math Olympiad (IMO) participants. Although he writes that “target readers are challenging high schools students and undergraduate students“, it appears to be quite advanced. It occurred to me to ask, do these IMO ...

Wasn't there someone in here a day or two ago claiming that Motl must be one of the smartest mathematicians on SE because he earned an IMO bronze?

Anonymous

@DawoodibnKareem IMO is a school level examination. Although it requires lots of practice and some bit of ingenuity to get through, it surely isn't related to actual research. The topics are just Euclidean geometry, Combinatorics, Number theory, and some bit of Algebra.

Dawood ibn Kareem

It's hardly school level.

Anonymous

@DawoodibnKareem The topics are school level. I know, because I had solved a few papers.

Dawood ibn Kareem

I strongly disagree.

Anonymous

The problems are not school level, but the topics are.

Anonymous

07:01

If you disagree, you need to show proof

Dawood ibn Kareem

There's no such thing as a "school level topic". You can study any topic you like to any level you like. Topics and levels are orthogonal.

Anonymous

While preparing for JEE, in our test series papers we almost always had a few hand-picked problems from previous IMO papers

Anonymous

Yes, you need to study some extra things

Anonymous

@DawoodibnKareem I don't even understand what your claim is

Anonymous

Euclidean geometry, Combinatorics, etc were taught to us in school

Dawood ibn Kareem

07:03

I am disputing your assertion that "IMO is a school level examination". It is not.

Anonymous

@DawoodibnKareem Well, college students aren't allowed to appear for it. Only school students are.

Anonymous

Upto grade 12

Dawood ibn Kareem

Most academic mathematicians with PhDs would struggle to score 42/42 in 9 hours on an IMO paper.

Anonymous

@DawoodibnKareem Sure. I'm not disputing that.

Dawood ibn Kareem

@Blue Yes, I know that. That doesn't mean it's school level.

Anonymous

07:05

It's mainly because they're out of touch with those type of problems

Anonymous

It needs practice

Anonymous

@DawoodibnKareem Your and my definition of school level are different.

Anonymous

By "school level" I meant school students appear for it

Dawood ibn Kareem

OK.

Anyway, my point is, the person who was in here glorifying Professor Motl had it wrong.

It would be interesting to know how many Stack Exchange users hold IMO medals. An absolutely impossible statistic to obtain.

I'm certain Motl is not alone.

Anonymous

Anyhow, my point is, PhD mathematicians not being able to score 42/42 on an IMO paper, is not because they are incompetent, but rather because they haven't been practicing those kind of problems for a long time. Here, students prepare for nearly 4 years for appearing for JEE/Olympiads etc. So they are better equipped for handling those type of problems.

Anonymous

07:10

And almost every year 2-3 people from our institute would go to the IMOs. It wasn't an irregular feat

Anonymous

Out of them, not more than 5% would grow up to be professional mathematicians

Anonymous

One of them even went on to take up a medical degree

Anonymous

@DawoodibnKareem Sure

Anonymous

@DawoodibnKareem We concur on that.

Dawood ibn Kareem

I don't think there is a single academic mathematician in my country who has participated at an IMO. I certainly can't think of one.

John Rennie

07:13

Motl is (was?) a world class theoretical physicist, notwithstanding misleading claims about the IMO.

Anonymous

Yes, let's stop at that. He's a good physicist, albeit with some controversial ideas. People shouldn't extend that to good mathematician.

Dawood ibn Kareem

Yes, agreed.

John Duffield

08:05

@Blue : would you care to list Motl's contribution to physics?

Anonymous

@JohnDuffield No.

Dawood ibn Kareem

@JohnDuffield contribution singular? If you list one thing, is it really a list?

John Duffield

@Blue : I reviewed Tomasso Dorigo's book, see his blog. Motl made a contribution to physics in the comments.

@DawoodibnKareem : typo. Sorry.

Dawood ibn Kareem

@JohnDuffield The book sounds interesting.

John Duffield

@DawoodibnKareem : I like that kind of stuff. I've read a lot of "science history" books like that. Dorigo gave a lot of little anecdotes about the Tevatron, it felt like being there.

But note that I have a special interest, somebody who doesn't might not like the book so much.

Dawood ibn Kareem

08:18

I might read half of it and stop.

John Duffield

@DawoodibnKareem : if you were interested in the discovery of the top quark, and what was actually discovered, you'd read the whole thing.

John Rennie

I think we have seen enough about Motl. Constructive comments about his physics are still welcome but non-constructive ones about him personally are not.

→ 1 message moved to trash

Slereah

No need to remove the PSE official logo

Dawood ibn Kareem

@JohnDuffield Maybe. I sometimes feel like I need a "quarks for dummies".

John Duffield

@DawoodibnKareem : I've done a lot of reading about the history of particle physics in recent months. Enough to say that IMHO there are some issues with the quark model.

IMHO there are other issues too, going back to Yakov Frenkel’s 1926 paper on the electrodynamics of rotating electrons.

Wolfgang Pauli referred to it in his 1926 paper on the quantum mechanics of magnetic electrons.

Dawood ibn Kareem

08:30

Well, I've always thought of it just as a model, not something you'd ever expect to find.

Therefore, I find the top quark surprising.

John Duffield

@DawoodibnKareem : other people don't I'm afraid.

Dawood ibn Kareem

I know. This is why I'm not a physicist. I have no more desire to find an actual quark than to find a maggot in my rice krispies.

John Duffield

And they don't ask the simple questions. Like in low-energy proton-antiproton annihilation to gamma photons, where do all the quarks and gluons go?

Secret

I guess a more precise question will be in low-energy proton-antiproton annihilation to gamma photons, why do all the quarks and gluons go?

John Duffield

Talking of gluons, see Wikipedia: "There are also conjectures about other exotic hadrons in which real gluons (as opposed to virtual ones found in ordinary hadrons)". The gluons in a proton are virtual. As in not real.

Secret

08:34

if you think about it, particles are kinda weird in that they can interconvert between each other as long they have the same energy and obey $e^2=p^2c^4+m^2c^2$

Dawood ibn Kareem

How does one tell the difference between a virtual gluon and a real gluon?

Secret

but it is uncertain whether we can figure out why

John Rennie

@DawoodibnKareem virtual particles don't exist. They are a mathematical abstraction.

Dawood ibn Kareem

Sure. So why don't we consider quarks a mathematical abstraction?

Secret

@DawoodibnKareem In the feymann diagrams, they are internal edges, in reality, they are really a feature of perturbative expansion. It is more likely that in reality, all you have is just some interactions and no notions of particles inside those high energy collisions

Slereah

08:37

All particles are a mathematical abstraction

John Rennie

@DawoodibnKareem (real) quarks are excitations of the quark quantum field. They are well defined things with real energy and momentum.

Slereah

In the end we only read numbers on a dial

or we see spots on a sheet

Secret

that's true

Dawood ibn Kareem

So that brings me back to my question. If all particles are mathematical abstractions, and none of them exist, how does one distinguish a virtual gluon from a real gluon?

John Duffield

@DawoodibnKareem : what real gluons? A virtual particle is not a short-live real particle that obligingly pops into existence. It only exists in the mathematics of the model. And the gluons in a proton are virtual. As in not real.

John Rennie

08:38

Virtual particles, all virtual particles, are excitations of the quantum field that cannot simply be described as particles. We model them as a sum of different particle states. The states appearing in that sum are the virtual particles.

Slereah

If it's on-shell or not

Although here's a trick

All photons you can detect are virtual

Because a photon is emitted by a vertex, and detected by another vertex

John Rennie

That's not really true

Slereah

It is!

It's very close to be on-shell, of course

John Rennie

Technically it's true, but in practice it's not helpful.

Slereah

Since it's on a very large scale

John Duffield

08:39

@Slereah : er, no. The photons you're detecting right now are real. Those vertices are not.

Secret

but then, we will end up with this weird conclusion that the very fact we see light will be virtual under that logic?

Slereah

as you well know :p

Secret

enters a partial existential crisis on exactly how much of the real world is real

Slereah

It's also not unlikely that particles are virtual, since it's not unlikely they will be annihilated at some point in their life :p

John Duffield

@Slereah : Those vertices only exist in the mathematics of the model too. The map is not the territory.

Slereah

08:41

but that's a bit stupider

John Rennie

@DawoodibnKareem when you quantise a quantum field you get field states, just as when you quantise particles you get particle states. In the non-interacting limit i.e. when the particles are too widely separated for interactions to be significant, those states are well defined states called Fock states.

John Duffield

Work calls, bye.

Slereah

Fock states aren't real states >:|

They're not even localized

John Rennie

A Fock state isn't especially complicated. In effect it's just an infinite plane wave.

Secret

tbh, in QFT, the thing I really interested is the messy interacting regime, but so far our supercomputers are simply not powerful enough to simulate e.g. protoon proton collisions

John Rennie

08:42

Just like the free particle states that we all learned about when we first started QM.

Slereah

which is also not a physical state

John Rennie

@DawoodibnKareem does this make sense so far?

@Slereah ssh!

Slereah

Heheh

John Rennie

:-)

Slereah

All physics is a liiie

It's pretty hard to really find a book talking about what physical states are like

unless you go for very practical books

Like quantum optics books

Since they're very concerned about measuring real, non-asymptotic states

Dawood ibn Kareem

08:45

@JohnRennie Well yes. At some point, you stop describing reality and start doing mathematics instead.

John Rennie

@DawoodibnKareem all of physics is a mathematical model that describes reality

5

Secret

this is such an important comment that i must star it

John Rennie

Whether the model is the reality is something that physics can't answer.

You need to go harass the philosophers with that one.

Secret

we can even argue that in some cases even philosophy don't have an answer

Slereah

Don't harrass the philosophy majors, they have hamburgers to sell

Dawood ibn Kareem

08:47

Philosophy never has an answer.

Secret

they are really high level stuff

John Rennie

@DawoodibnKareem the point is that QFT works i.e. the descriptions it provides correspond to experimental results. In fact they ciorrespond exceedingly closely to experimental results.

Secret

In particular, QED is the most accurate model we have of all physics models

Slereah

for some reason when you have people criticizing existing theories, they never furnish new ones that fit all experimental data afterward!

Although that would be quite a lot of data for QFT I suppose

Dawood ibn Kareem

OK, but humour me for a moment. If you're studying cell biology, you could imagine shrinking yourself down very small, like smaller than a cell, and swimming round inside a cell to see what's there. When you see the pictures of a cell's structure in your biology textbook, you think "those are real things", and you know that if you were small enough, you could run into the occasional mitochondrion, or whatever.

Secret

08:49

hadron collision jet patterns, decay channels, lifetime of particles, energy deposites and so on

Slereah

but if your brand new theory can't even explain the Zeeman effect, not much good it can do

That is your monkey brain trying to relate everything to familiar concepts

Like physical objects

that you can see and touch

Dawood ibn Kareem

If you're studying chemistry (an anagram of mercy sh** - who knew?) you could imagine shrinking yourself even smaller, say the size of a hydrogen atom, and seeing what the actual molecules are doing.

Secret

@DawoodibnKareem Technically, those pictures are just illustrations, they don't 100% reflect what a cell look like. The reason why the above observation works for cell is because they are not small enough for the weirdness of quantum mechanics to play signifcant role that give things counter to our intuition

Slereah

The molecules are already doing quantum business, though

Secret

similarly, every atom in a molecule is not really a sphere, and they are more like probability clouds of electron density

Dawood ibn Kareem

08:52

Then, when you get into "very small physics", you kind of want to be smaller than a proton, so you can actually see what quarks look like. You expect that at some point, you're going to see little red, green and blue balls.

But no, you're not allowed to do that without becoming a figment of a deranged mathematical imagination.

John Rennie

@DawoodibnKareem you can't see molecules. Light doesn't scatter off them. You have to go to some other probe and that immediately ceases to correspond to anything intuitive to humans.

Dawood ibn Kareem

Sure you can't see molecules. But you can imagine seeing molecules.

Slereah

Well you can also imagine seeing quarks

it's wrong but knock yourself out

Dawood ibn Kareem

You can play with little plastic balls and sticks.

Secret

quarks cannot have colors, cause they are smaller than optical wavelength. We call that color charge simply because it has 3 kinds, thus we use the RGB as analogy and the name then sticks

John Rennie

08:53

@DawoodibnKareem The belief that anything you can't imagine can't exist is the starting point for the crackpot.

Slereah

Molecules can be in superpositions states too, but you don't seem to be too bothered by it

Dawood ibn Kareem

It's human nature to like imagining things.

John Rennie

Our own much beloved GR guru suffers from exactly this affliction.

Secret

GR is harder than quanutm IMO. cause it f888 up the intuitive notion of distance

Slereah

It's usually a good idea to try to imagine some visual metaphore for physical process, but you have to realize that it has its limits

Dawood ibn Kareem

08:55

@Secret Yes, I realise that quarks aren't actually covered in three types of paint.

Secret

thus I lost an anchor to "see" where the concepts are oriented, so to speak

John Rennie

@DawoodibnKareem QM put a clean end to that belief

Even in non-relativistic regular QM particles are very strange objects

Dawood ibn Kareem

QM didn't change human nature.

Slereah

Hell even action at a distance was considered fairly offensive back then

People just wanted it to be related to fluid forces

John Rennie

QM was the point where human nature and physics diverged.

Secret

08:56

I love weird and counterintuitive things because of the bigger world it can taught me that my biological brain don't commonynl access

Slereah

@JohnRennie Special relativity, even

Dawood ibn Kareem

@JohnRennie OK, fair enough, I will grant you that. But it seems that biology and chemistry try to describe actual things, whereas physicists gaze at their navels in the hope of constructing models.

Slereah

Well you know the saying

John Rennie

@Slereah yes, that's true. I guess I consider SR intuitive after all these years :-)

Slereah

If it's stupid and it works, it's not stupid

John Rennie

08:58

@DawoodibnKareem but our models work!

Dawood ibn Kareem

GR at least makes a kind of sense. You can measure what stars and planets are doing, and notice gravitational effects.

Slereah

And obviously you haven't been doing quantum chemistry :p

Dawood ibn Kareem

@JohnRennie Models working is not enough.

John Rennie

@DawoodibnKareem Yes it is

Slereah

@DawoodibnKareem also you haven't been reading enough GR, I'd say

GR is insane

John Rennie

08:58

@DawoodibnKareem This is exactly the point that divides mainstream physics from the crackpot

Secret

SR is still ok for me because minkowski diagram with a suitable way to interpret angles can pretty much capture most of the maths, but the way it distort spacetime still need some time to get used to

Dawood ibn Kareem

If I could make the phlogiston model work, would you start believing phlogiston was a thing?

Slereah

or at least the possible consequences

@DawoodibnKareem what do you mean by "a thing"

As said, physics isn't about what's real

Secret

GR, on the other hand, you can no longer draw diagrams without massively distorting what the model is describing

John Rennie

@DawoodibnKareem if you could make phlogiston work better than existing theories I'd take it seriously. But you can't so it's a meaningless question.

Dawood ibn Kareem

08:59

Most of physics is about what's real.

Slereah

You only think that because you have the benefit of modernity

John Rennie

@DawoodibnKareem agreed. At the end of the day we are trying to predict real observations.

Slereah

A lot of what you considered "classical" physics was considered stupid and unintuitive for the longest time

Galilean relativity was poorly considered

Same with Newtonian gravity

John Rennie

@DawoodibnKareem And our current models do that better than any other models. That's why they are our current models.

Slereah

Or the concept of a void

or electromagnetic forces

Secret

09:01

In fact, I kinda thank Johnrennie in one of his PSE describing how the expansion of spacetime is mathematically speaking, the metric itself is changing, thus rather than having more space being produced, the grid itself becomes bigger so tospeak

Slereah

All of these things were considered as philosophically untennable at various points

We just kinda accept them these days because they've been around for a while and have proven themselves in day to day applications

Secret

O and btw, we won't be chatting right now if e.g. turing etc. don't take logic seriously and build computers

and logic is like the most abstract thing in existence

John Rennie

@DawoodibnKareem you can make a theory better in two ways:
1. predict experiment more accurately
2. keep the current accuracy but make the theory simpler

Secret

The field of information technology pretty much arises from a spinoff in studying logic

Slereah

Or you can make the theory more complicated

Occam's razor shouldn't dictate what you do for fun

I mean, if you have a more intuitive theory for QFT that accounts for all observations

John Rennie

09:04

Both are actively pursued by physicists, and option (2) is a perfectly valid way to spend your research budget. But just saying a theory is bunk because it's too complicated is not physics.

Slereah

Feel free to try

But I must warn you that it has been tried quite a lot

Secret

Sometimes it makes me curious, can cantorian infinities/infinite cardinals one day ever spawn a technology that will transform our civillisation like the internet does?

John Rennie

QFT is actually pretty simple in concept, but it turns out we can't compute the field states for an interacting theory. The hideous complexity that characterises modern QFT is all concerned with finding approximate ways to get round this.

Dawood ibn Kareem

Well, let's take an electron as an example. As we learn science at school, we first meet tiny little balls zooming around nuclei. And we think of electrons as particles. Then we learn that they're not particles at all, so we change our mental model of what an electron is like. Then we learn that they don't really have position, or momentum, or any of the things that exist in the picture of little balls zooming around nuclei. But that's OK, because they're still things - just different

types of things. But it's an even bigger leap to say - no these aren't things, they're just a mathematical model that explains how chemistry works, and how electric circuits work, and how all sorts of other stuff works that needs electrons. Nobody wants their electrons taken away from them.

John Rennie

The electron is certainly a thing. No-one is saying it's not.

We're just saying it's a stranger thing than most people know.

Secret

09:06

Dawood: Your above discussion reminds of a philosophical discussion between me and my physical professor back in 1st year. We discussed about what exactly is an electron and we then conclude we may never have an answer

Slereah

The status of the electron hasn't changed, it's still a vector in a Hilbert space!

Dawood ibn Kareem

30 mins ago, by Slereah

All particles are a mathematical abstraction

Slereah

It's just that the operators involved have changed

John Rennie

@DawoodibnKareem the maths is a description of the electron.

Slereah

A mathematical abstraction is a thing, too :p

Secret

09:08

nothingness is a thing for example

John Rennie

@DawoodibnKareem Sam is being mischievous I'm afraid

Slereah

Only a little

Secret

he's always like that, deal with it :P

Slereah

It is still true that particles in the end are just an abstraction

John Rennie

What he means is that Fock states don't exist in the real world.

Slereah

09:09

But then you can say that about most physical concepts

John Rennie

But though a Fock state is only an approximate description of a real particle it's an exceedingly good approximation.

Slereah

Errrr

I'm not sure I agree with that

Dawood ibn Kareem

Here's my issue. A proton is a thing. But it's made of three things that aren't things.

Slereah

Real particles are better described by wave packets

John Rennie

@DawoodibnKareem wrong.

Quarks are real things

Why would you say they aren't?

Secret

09:10

but do wavepacket description still hold in relativistic conditions like a quantum field?

Dawood ibn Kareem

@JohnRennie And the gluons?

John Rennie

@DawoodibnKareem The gluons in a proton are mostly virtual gluons, but real gluons certainly exist. We see them in collider experiments.

Slereah

Well, we see gluon jets

I wouldn't go as far as saying we see gluons

John Rennie

@Slereah yes, that's what I meant.

Dawood ibn Kareem

OK, so the three things that are things are held together by a bunch of things that aren't things?

Slereah

09:12

Although if you're worried about quarks, remember that we can do scattering experiments on quarks

We can blast electrons at protons to scatter them off the quarks

Secret

To be honest, I don't even knew whether a gluon microscope will work in practice...

Slereah

for very high energy electrons

John Rennie

@DawoodibnKareem consider two protons interacting via the usual EM force. The interaction energy is much less than the proton rest mass energy.

So interacting protons are in effect slightly perturbed isolated protons.

Slereah

@DawoodibnKareem would you say that the EM field isn't a thing in classical mechanics?

Dawood ibn Kareem

@JohnRennie I feel their pain.

John Rennie

09:14

@DawoodibnKareem Now imagine turning up the strength of the interaction so the energy is the same as the proton rest mass. Is it best to describe this as two protons plus an interaction, or as an interaction plus two protons?

Dawood ibn Kareem

@Slereah Actually, that makes sense.

John Rennie

@DawoodibnKareem In a proton the interaction energy is about 1,000 times bigger than the rest mass energy of the quarks.

Slereah

The gluon field isn't terribly different from the EM field

It's just that it can't really make "gluon waves"

John Rennie

@DawoodibnKareem So basically we are looking at an interaction slightly perturbed by the presence of three quarks.

Slereah

But if an EM field just holds two particles together, it's not any less real

Dawood ibn Kareem

09:16

@Slereah well, it kind of is.

Slereah

Don't doubt it too much, it's what holds your body together :p

Dawood ibn Kareem

Yes, but it will hold my body together whether I doubt it or not. Like Niels Bohr's horse shoe.

Slereah

09:28

Where will she get money for her gaudy pearl necklaces and panel painting bracelets

Dawood ibn Kareem

@JohnRennie Before or after MBS's visit?

John Rennie

@DawoodibnKareem see here

Dawood ibn Kareem

10:16

I can't resist sharing this.

8

A: Getting rid of ants and insect Islamic way?

It is prohibited to kill ants. The Prophet {Peace Be Upon Him} has prohibited the killing of ants and three other creatures: Narrated Abdullah ibn Abbas : The Prophet (sallallahu 'alaihi wa sallam) prohibited to kill four creatures: ants, bees, hoopoes, and sparrow-hawks. حَدَّثَ...

John Rennie

Speaking as a room owner I think extended discussion of personal theories of philosophy are inappropriate here and I ask that they stop. Unless there is a mass outcry I will start removing future posts of this type.

→ 3 messages moved to trash

Kenshin

@JohnRennie, can you please delete the message blocks I will flag

John Rennie

Flag? If you mean the chat flagging facility I wouldn't do that.

Kenshin

y not

John Rennie

Why don't I simply delete the entire discussion?

Kenshin

10:30

if u want, I didn't want to create too much work fo ru

John Rennie

@Kenshin Chat flags are for seriously offensive posts. They notify every moderator and 10K user on the while SE. Using them to mark posts for deletion will make you very unpopular!

Kenshin

I didn't know, there is no signs indicating that the flags shouldn't only be used for seriously offensive posts tho

Balarka Sen

I don't think there's anything per se wrong about talking about philosophy in this room. I just think Kenshin's extended semi-logical babble belongs to a blog of his own, not in this room

Kenshin

ty @BalarkaSen, maybe I should start my own blog

@JohnRennie, will you please delete the babble tho

John Rennie

→ 53 messages moved to trash

Kenshin

10:34

it's still there

I appreciate the effort, but it seems all the messages prior to the theory were deleted

but the theory itself remains

Rand al'Thor

@Kenshin There are two types of chat flags: "rude/offensive" flags (using the little flag icon next to a message) and "flag for moderator" (which appears on the drop-down menu for a message). The latter can be used for simply asking that some of your own messages be removed, if it's important. But John Rennie isn't a moderator, so he wouldn't see those flags.

John Rennie

→ 38 messages moved to trash

Kenshin

ah i I see thanks alot @Randal'Thor

I thin I did use the "flag for moderator" one here, but didn't realise John couldn't see it.

ty @JohnRennie

John Rennie

→ 66 messages moved to trash

Kenshin

I can now delay publishing without fear of my ideas being stolen

Balarka Sen

10:38

https://en.wikipedia.org/wiki/Grandiose_delusions

Curb Your Enthusiasm Theme

►

John Rennie

→ 2 messages moved to trash

Slereah

This is why I always advise to have a rule to throw cranks out :p

It served us well on the freenode physics channel

Kenshin

@BalarkaSen, please don't insinuate I have a psychiatric disorder, I find that highly offensive

Dawood ibn Kareem

John, it seems you invited me twice to the trash room. I'm not sure the significance of that. Surely you don't need me there for anything?

Anonymous

Oh! I missed the philosophy trash talk! :D

Anonymous

10:39

Bad timing

Kenshin

@JohnRennie, can Balarka's post please be moved to the trash

Slereah

You're a lucky man

Anonymous

@DawoodibnKareem You get invited automatically by the system

Anonymous

When you message is trashed

Slereah

It wasn't even fun physics philosophy

Kenshin

10:40

it was great @Blue, my theory really did explain everything,but you will have to wait until I publish it

John Rennie

I'm moving the lot, but it's taking a while ...

Slereah

It was your bog standard ethics rambling

Dawood ibn Kareem

@Blue OK, it's just never happened to me before.

John Rennie

→ 19 messages moved to trash

→ 18 messages moved to trash

Right, I think that's the lot ...

Kenshin

thanks John

Anonymous

10:43

@Kenshin Sure, I'll be waiting with my fingers crossed.

Balarka Sen

@Kenshin I didn't insinuate anything, I posted a link to a wikipedia page. If you find psychiatric disorder inherently offensive you're part of the crowd that stereotypes it.

Tough choice, given you're the man who is talking about ethics and morality

John Rennie

@DawoodibnKareem weird. It must have happened when I moved the messages.

Kenshin

@BalarkaSen, under my theory, being offended by psychiatric disorder isn't "immoral" tho

Dawood ibn Kareem

@JohnRennie That's Blue's theory, yes. He has more experience of having his messages trashed than I do.

Kenshin

@JohnRennie can you please delete Balarka's link to the psychiatric page, it is either an attack, or it is an irrelevant link

Dawood ibn Kareem

10:45

Kenshin, will you give it a rest already? John is under no obligation to delete messages that you dislike.

Secret

@JohnRennie why are personal theories of philosophy inapproporiate. They are not actively promoting misinformation as far I knew since philosophy really don't have a notion of accuracy?

Kenshin

that's fine, i can flag it for being offensive

Balarka Sen

@Secret It's not per se inappropriate, it just doesn't belong to a public chat. It's the same argument that's been said against your extended write-ups on algebraic structures and stuff in here.

The standard alternative is to get a blog.

Kenshin

@Secret that is generally the case, my theory however was different in that it had an abnormally high degree of accuracy, causing much offence

Balarka Sen

And if you want to share it, link to the relevant blog page.

Secret

10:47

@BalarkaSen right makes sense

Dawood ibn Kareem

Facepalm

John Rennie

@Secret it's not that philosophy is banned, but when it appears to be turning into an extended monologue I don't think it serves the main physics chat room well.

But as I said I wouldn't go against the wishes of the chat room regulars.

Manolis Lyviakis

how to prove that the dipole

Kenshin

I'm happy with whichever way you think will have the least repercussions

Manolis Lyviakis

dipoles motion in a uniform field is a oscilation?

i know its only fore is torque

qEsinθL-ma=0 if i apply newtons law

Kenshin

10:55

@ManolisLyviakis, by using a combination of mathematical and visual reasoning

Manolis Lyviakis

can i integrate it?

i can visually see it

but i have to derive an oscilation equation

Kenshin

which paramters do u think vary over time in ur equation

Manolis Lyviakis

only the angle

Nehal Samee

I think you should use τ=Iα=-Fr ..

John Rennie

@ManolisLyviakis use the angular equivalent of the second law: $$ T = I\ddot{\theta}$$

Nehal Samee

10:57

For proving S.H.O. ... Not sure...

Manolis Lyviakis

john ohh

John Rennie

When you write this down for your dipole you'll find you have the equation for simple harmonic motion.

Manolis Lyviakis

thats what i was trying to do thanks

i i wrote F=ma which is actually the same

y-y''=0 has sollutions ACosθ+BsinΘ ριγητ?

right*

y+y''=0 is the hyperbolic ones

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