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12:09 AM
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
 
 
1 hour later…
1:34 AM
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
 
@Slereah How'd you upload a vector graphic?
 
 
1 hour later…
vzn
3:01 AM
@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
3:44 AM
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...
 
4:17 AM
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
 
4:42 AM
red pill blue pill -----> user list
 
5:36 AM
@Blue You overran your buffer, because strcat includes a terminating zero. So no, your C code is NOT OK.
 
6:07 AM
Some rocket science and economics
 
6:20 AM
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.
 
6:49 AM
31
Q: Does the International Math Olympiad help research mathematics?

JimI 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.
 
It's hardly school level.
 
Anonymous
@DawoodibnKareem The topics are school level. I know, because I had solved a few papers.
 
I strongly disagree.
 
Anonymous
The problems are not school level, but the topics are.
 
Anonymous
7:01 AM
If you disagree, you need to show proof
 
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
 
7:03 AM
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
 
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.
 
@Blue Yes, I know that. That doesn't mean it's school level.
 
Anonymous
7:05 AM
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
 
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
7:10 AM
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.
 
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.
 
7:13 AM
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.
 
Yes, agreed.
 
8:05 AM
@Blue : would you care to list Motl's contribution to physics?
 
Anonymous
@JohnDuffield No.
 
@JohnDuffield contribution singular? If you list one thing, is it really a list?
 
@Blue : I reviewed Tomasso Dorigo's book, see his blog. Motl made a contribution to physics in the comments.
@DawoodibnKareem : typo. Sorry.
 
@JohnDuffield The book sounds interesting.
 
@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.
 
8:18 AM
I might read half of it and stop.
 
@DawoodibnKareem : if you were interested in the discovery of the top quark, and what was actually discovered, you'd read the whole thing.
 
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
 
No need to remove the PSE official logo
 
@JohnDuffield Maybe. I sometimes feel like I need a "quarks for dummies".
 
@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.
 
8:30 AM
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.
 
@DawoodibnKareem : other people don't I'm afraid.
 
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.
 
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?
 
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?
 
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.
 
8:34 AM
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 $e^2=p^2c^4+m^2c^2$
 
How does one tell the difference between a virtual gluon and a real gluon?
 
but it is uncertain whether we can figure out why
 
@DawoodibnKareem virtual particles don't exist. They are a mathematical abstraction.
 
Sure. So why don't we consider quarks a mathematical abstraction?
 
@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
 
8:37 AM
All particles are a mathematical abstraction
 
@DawoodibnKareem (real) quarks are excitations of the quark quantum field. They are well defined things with real energy and momentum.
 
In the end we only read numbers on a dial
or we see spots on a sheet
 
that's true
 
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?
 
@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.
 
8:38 AM
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.
 
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
 
That's not really true
 
It is!
It's very close to be on-shell, of course
 
Technically it's true, but in practice it's not helpful.
 
Since it's on a very large scale
 
8:39 AM
@Slereah : er, no. The photons you're detecting right now are real. Those vertices are not.
 
but then, we will end up with this weird conclusion that the very fact we see light will be virtual under that logic?
 
as you well know :p
 
enters a partial existential crisis on exactly how much of the real world is real
 
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
 
@Slereah : Those vertices only exist in the mathematics of the model too. The map is not the territory.
 
8:41 AM
but that's a bit stupider
 
@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.
 
Work calls, bye.
 
Fock states aren't real states >:|
They're not even localized
 
A Fock state isn't especially complicated. In effect it's just an infinite plane wave.
 
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
 
8:42 AM
Just like the free particle states that we all learned about when we first started QM.
 
which is also not a physical state
 
@DawoodibnKareem does this make sense so far?
@Slereah ssh!
 
Heheh
 
:-)
 
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
 
8:45 AM
@JohnRennie Well yes. At some point, you stop describing reality and start doing mathematics instead.
 
@DawoodibnKareem all of physics is a mathematical model that describes reality
5
 
this is such an important comment that i must star it
 
Whether the model is the reality is something that physics can't answer.
You need to go harass the philosophers with that one.
 
we can even argue that in some cases even philosophy don't have an answer
 
Don't harrass the philosophy majors, they have hamburgers to sell
 
8:47 AM
Philosophy never has an answer.
 
they are really high level stuff
 
@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.
 
In particular, QED is the most accurate model we have of all physics models
 
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
 
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.
 
8:49 AM
hadron collision jet patterns, decay channels, lifetime of particles, energy deposites and so on
 
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
 
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.
 
@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
 
The molecules are already doing quantum business, though
 
similarly, every atom in a molecule is not really a sphere, and they are more like probability clouds of electron density
 
8:52 AM
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.
 
@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.
 
Sure you can't see molecules. But you can imagine seeing molecules.
 
Well you can also imagine seeing quarks
it's wrong but knock yourself out
 
You can play with little plastic balls and sticks.
 
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
 
8:53 AM
@DawoodibnKareem The belief that anything you can't imagine can't exist is the starting point for the crackpot.
 
Molecules can be in superpositions states too, but you don't seem to be too bothered by it
 
It's human nature to like imagining things.
 
Our own much beloved GR guru suffers from exactly this affliction.
 
GR is harder than quanutm IMO. cause it f888 up the intuitive notion of distance
 
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
 
8:55 AM
@Secret Yes, I realise that quarks aren't actually covered in three types of paint.
 
thus I lost an anchor to "see" where the concepts are oriented, so to speak
 
@DawoodibnKareem QM put a clean end to that belief
Even in non-relativistic regular QM particles are very strange objects
 
QM didn't change human nature.
 
Hell even action at a distance was considered fairly offensive back then
People just wanted it to be related to fluid forces
 
QM was the point where human nature and physics diverged.
 
8:56 AM
I love weird and counterintuitive things because of the bigger world it can taught me that my biological brain don't commonynl access
 
@JohnRennie Special relativity, even
 
@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.
 
Well you know the saying
 
@Slereah yes, that's true. I guess I consider SR intuitive after all these years :-)
 
If it's stupid and it works, it's not stupid
 
8:58 AM
@DawoodibnKareem but our models work!
 
GR at least makes a kind of sense. You can measure what stars and planets are doing, and notice gravitational effects.
 
And obviously you haven't been doing quantum chemistry :p
 
@JohnRennie Models working is not enough.
 
@DawoodibnKareem Yes it is
 
@DawoodibnKareem also you haven't been reading enough GR, I'd say
GR is insane
 
8:58 AM
@DawoodibnKareem This is exactly the point that divides mainstream physics from the crackpot
 
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
 
If I could make the phlogiston model work, would you start believing phlogiston was a thing?
 
or at least the possible consequences
@DawoodibnKareem what do you mean by "a thing"
As said, physics isn't about what's real
 
GR, on the other hand, you can no longer draw diagrams without massively distorting what the model is describing
 
@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.
 
8:59 AM
Most of physics is about what's real.
 
You only think that because you have the benefit of modernity
 
@DawoodibnKareem agreed. At the end of the day we are trying to predict real observations.
 
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
 
@DawoodibnKareem And our current models do that better than any other models. That's why they are our current models.
 
Or the concept of a void
or electromagnetic forces
 
9:01 AM
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
 
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
 
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
 
@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
 
The field of information technology pretty much arises from a spinoff in studying logic
 
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
 
9:04 AM
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.
 
Feel free to try
But I must warn you that it has been tried quite a lot
 
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?
 
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.
 
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.
 
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.
 
9:06 AM
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
 
The status of the electron hasn't changed, it's still a vector in a Hilbert space!
 
30 mins ago, by Slereah
All particles are a mathematical abstraction
 
It's just that the operators involved have changed
 
@DawoodibnKareem the maths is a description of the electron.
 
A mathematical abstraction is a thing, too :p
 
9:08 AM
nothingness is a thing for example
 
@DawoodibnKareem Sam is being mischievous I'm afraid
 
Only a little
 
he's always like that, deal with it :P
 
It is still true that particles in the end are just an abstraction
 
What he means is that Fock states don't exist in the real world.
 
9:09 AM
But then you can say that about most physical concepts
 
But though a Fock state is only an approximate description of a real particle it's an exceedingly good approximation.
 
Errrr
I'm not sure I agree with that
 
Here's my issue. A proton is a thing. But it's made of three things that aren't things.
 
Real particles are better described by wave packets
 
@DawoodibnKareem wrong.
Quarks are real things
Why would you say they aren't?
 
9:10 AM
but do wavepacket description still hold in relativistic conditions like a quantum field?
 
@JohnRennie And the gluons?
 
@DawoodibnKareem The gluons in a proton are mostly virtual gluons, but real gluons certainly exist. We see them in collider experiments.
 
Well, we see gluon jets
I wouldn't go as far as saying we see gluons
 
@Slereah yes, that's what I meant.
 
OK, so the three things that are things are held together by a bunch of things that aren't things?
 
9:12 AM
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
 
To be honest, I don't even knew whether a gluon microscope will work in practice...
 
for very high energy electrons
 
@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.
 
@DawoodibnKareem would you say that the EM field isn't a thing in classical mechanics?
 
@JohnRennie I feel their pain.
 
9:14 AM
@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?
 
@Slereah Actually, that makes sense.
 
@DawoodibnKareem In a proton the interaction energy is about 1,000 times bigger than the rest mass energy of the quarks.
 
The gluon field isn't terribly different from the EM field
It's just that it can't really make "gluon waves"
 
@DawoodibnKareem So basically we are looking at an interaction slightly perturbed by the presence of three quarks.
 
But if an EM field just holds two particles together, it's not any less real
 
9:16 AM
@Slereah well, it kind of is.
 
Don't doubt it too much, it's what holds your body together :p
 
Yes, but it will hold my body together whether I doubt it or not. Like Niels Bohr's horse shoe.
 
9:28 AM
Where will she get money for her gaudy pearl necklaces and panel painting bracelets
 
@JohnRennie Before or after MBS's visit?
 
@DawoodibnKareem see here
 
10:16 AM
I can't resist sharing this.
8
A: Getting rid of ants and insect Islamic way?

مجاهدIt 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...

 
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
 
@JohnRennie, can you please delete the message blocks I will flag
 
Flag? If you mean the chat flagging facility I wouldn't do that.
 
y not
 
Why don't I simply delete the entire discussion?
 
10:30 AM
if u want, I didn't want to create too much work fo ru
 
@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!
 
I didn't know, there is no signs indicating that the flags shouldn't only be used for seriously offensive posts tho
 
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
 
ty @BalarkaSen, maybe I should start my own blog
@JohnRennie, will you please delete the babble tho
 
53 messages moved to trash
 
10:34 AM
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
 
@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.
 
38 messages moved to trash
 
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
 
66 messages moved to trash
 
I can now delay publishing without fear of my ideas being stolen
 
2 messages moved to trash
 
This is why I always advise to have a rule to throw cranks out :p
It served us well on the freenode physics channel
 
@BalarkaSen, please don't insinuate I have a psychiatric disorder, I find that highly offensive
 
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 AM
Bad timing
 
@JohnRennie, can Balarka's post please be moved to the trash
 
You're a lucky man
 
Anonymous
@DawoodibnKareem You get invited automatically by the system
 
Anonymous
When you message is trashed
 
It wasn't even fun physics philosophy
 
10:40 AM
it was great @Blue, my theory really did explain everything,but you will have to wait until I publish it
 
I'm moving the lot, but it's taking a while ...
 
It was your bog standard ethics rambling
 
@Blue OK, it's just never happened to me before.
 
19 messages moved to trash
18 messages moved to trash
Right, I think that's the lot ...
 
thanks John
 
Anonymous
10:43 AM
@Kenshin Sure, I'll be waiting with my fingers crossed.
 
@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
 
@DawoodibnKareem weird. It must have happened when I moved the messages.
 
@BalarkaSen, under my theory, being offended by psychiatric disorder isn't "immoral" tho
 
@JohnRennie That's Blue's theory, yes. He has more experience of having his messages trashed than I do.
 
@JohnRennie can you please delete Balarka's link to the psychiatric page, it is either an attack, or it is an irrelevant link
 
10:45 AM
Kenshin, will you give it a rest already? John is under no obligation to delete messages that you dislike.
 
@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?
 
that's fine, i can flag it for being offensive
 
@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.
 
@Secret that is generally the case, my theory however was different in that it had an abnormally high degree of accuracy, causing much offence
 
And if you want to share it, link to the relevant blog page.
 
10:47 AM
@BalarkaSen right makes sense
 
Facepalm
 
@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.
 
how to prove that the dipole
 
I'm happy with whichever way you think will have the least repercussions
 
dipoles motion in a uniform field is a oscilation?
i know its only fore is torque
qEsinθL-ma=0 if i apply newtons law
 
10:55 AM
@ManolisLyviakis, by using a combination of mathematical and visual reasoning
 
can i integrate it?
i can visually see it
but i have to derive an oscilation equation
 
which paramters do u think vary over time in ur equation
 
only the angle
 
I think you should use τ=Iα=-Fr ..
 
@ManolisLyviakis use the angular equivalent of the second law: $$ T = I\ddot{\theta}$$
 
10:57 AM
For proving S.H.O. ... Not sure...
 
john ohh
 
When you write this down for your dipole you'll find you have the equation for simple harmonic motion.
 
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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