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2:03 AM
@psa iirc, the issue is that the thermodynamic identity $dU=TdS-PdV$ is for systems undergoing microscopic changes in its state variables while in thermal equilibrium (or quasi-equilibrium? i forgete)
but the free expansion of a gas into vacuum isn't an equilibrium process
also, I see no reason to take the box as the volume. it's the gas which expands and the gas whose internal energy you're interested in
(you should still not get any work, since there's no pressure to resist said expansion)
(right, free expansion isn't quasi-static. that's what I was forgetting)
the basic issue is that, since it's not quasi-static, you can have an increase in entropy without having heat transfer
free expansion of a gas is an adiabatic process (no heat flow) but not reversible
 
 
2 hours later…
3:44 AM
I am completely dumbfounded
I'm trying to understand the kinematics of point masses using vectors
And I don't understand what this is trying to explain:
 
4:01 AM
OK, so u_t is the unit vector tangential to the particle's path, and u_n is the unit vector normal to the path
But I'm still not sure what the actual objective of the section is
 
psa
It's just establishing the Frenet-Serret frame.
 
Never heard of that. I'll check it out
 
psa
@DarkRunner Is there anything in particular that's confusing? It's mostly just talking about acceleration and $\mathbf{T}, \mathbf{N}, \mathbf{B}$ as a basis for the space that the particle is moving in.
That's a very math-y way of talking about kinematics though. It's usually only used in vector calculus classes.
What book is that?
 
@psa Orbital Mechanics for Engineering Students
I think I'm understanding! Basically, we have 3 vectors that describe the motion of any object in 3d space: The Tangent and Normal vector, of course, but also this new "Binormal" vector
 
psa
4:22 AM
@DarkRunner yeah. you of course need 3 vectors to form a basis of $\mathbb{R}^3$. the binormal vector serves that purpose. I think the physical intuition as far as what it describes is torsion.
so you've got velocity which is related to the tangent vector, curvature which is related to acceleration (and the normal vector) and torsion which is like the "3d-ness" of the curve.
 
 
2 hours later…
5:54 AM
eyy @dmckee---ex-moderatorkitten
 
6:51 AM
Is he here?
 
i saw him drop in at least
 
7:07 AM
Why are you awake so late in the night?
 
7:32 AM
@Knight well i'm probably not in your timezone :P
but insomnia
 
 
1 hour later…
8:59 AM
@SirCumference of which country are you a citizen?
 
Well in my area it's dark knight
 
My timezone is EST
 
What time it is there?
 
9:01 AM
Oho! You're are an early riser (quite too early)
 
i'm supposed to wake up at 8
this is me trying to sleep :P
 
Why both of us have this same problem?
It's 3 am here
And I don't whether I'm asleep or awake
 
oh you experience that too?
like sometimes i'll lie in bed and the hours will flow by, then i don't know if i slept or not
 
This causes stomach upsets and depression too
 
@SirCumference Apparently that's a thing
@Knight Hmm, I've been burnt out but haven't gotten those :/
you see a doctor?
 
9:06 AM
Doctors say sleeping disorders are caused by over thinking
 
I have found an incredible scientific fact
 
And sleeping disorder causes disorder in secretion of enzymes therefore stomach gets hurt
 
There's a rare GR book I want and it costs one dollar
 
Wow! Who wrote them?
 
is that a scientific fact
 
9:07 AM
Lol
👌
 
I have observed it using my senses
it is very much a scientific fact
 
fair enough
 
Are those books in readable condition?
@SirCumference How old are you?
 
21
wait crap
22 now
why is time flying so fast
i used to be 18
 
But you’re very calm which contradicts your age
@SirCumference I used to be in womb
 
9:11 AM
@Knight Only one way to find out
 
I used to be 98
 
@Slereah Didn’t get ya
 
@Knight huh?
@Knight literally the last 4 years have felt like a single year
 
In which university are you?
 
i heard time speeds up as you get older but i'm not supposed to be "older" yet
@Knight rather not say
 
9:13 AM
@SirCumference Slereah would describe it better
 
@Knight you an undergrad?
 
No
 
@SirCumference Get used to that feeling :P
 
No university is accepting me bcoz my records doesn’t suffice what they want
@ACuriousMind Can you give us hint for estimating your age?
 
...I'm turning 27 in two weeks.
 
9:16 AM
Happy birthday!
 
Impossible
 
(had to count three times to make sure that's right, this is difficult math)
 
How can you be just 26?
 
@Knight How can you be $x$ years old?
😂
 
It actually isn't very difficult :P
 
9:18 AM
@Knight get to 25 then keep breathing.
It's aging by induction :-)
 
@JohanLiebert Thanks (but careful - Germans and some other Europeans widely believe that it's bad luck to express such wishes before the actual day!)
 
Well I meant you see ACM’s knowledge, how can someone become that much accurate in his knowledge just by the age of 26
 
@ACuriousMind i was about to say happy birthday right before you said that lol
 
@JohnRennie Do you like playing with 2 year old kids?
 
I mean, I'm not superstitious but it still feels somewhat weird to me since I've been conditioned to not say that
 
9:20 AM
@Knight I don't know any two year old children. My niece vomited on me when she was a few weeks old, and that kind of put me off children for life.
 
@ACuriousMind But how come you’re so self dependent at such a small age
@JohnRennie Nevermind! My nieces did so many things on me.
 
@Knight I...don't really consider 26 "small". It's the "intended" age at which one would be expected to hold a university degree or otherwise have been working for a few years around here.
And I've been self-dependent ever since I've moved out from my parents years ago! :P
 
@ACuriousMindi don't know the exact date so thought to wish you earlier. If I go by the Hindu tradition then my DOB is not fixed in Gregorian calender!
 
@ACuriousMind But at the age of 26 people are still considered newbie in area of work and research, aren’t they?
@ACuriousMind You left your parents?
 
@Knight Sure
 
9:25 AM
@ACuriousMind But you’re not a newbie, how?
Why?
 
@Knight Well, they didn't live where I wanted to study (and now work), so yes, I moved out after school. That's not unusual.
 
@ACuriousMind How did you earn money for Unversity education and food, shelter and clothings and luxuries ?
 
-1
Q: Big what, how can we tell?

JohnWhy was the particle smaller than a grain of sand at the Big Bang and not something very massive that left all this dust and stuff out there.

what
 
What
 
Why??????
 
9:29 AM
@Knight Federally funded scholarship, but even if that hadn't been there, I'd have received a guaranteed federal loan like every other German citizen whose parents earn less than a certain threshhold.
@SirCumference Well, how can we tell?
 
@ACuriousMind Did you do post graduation?
 
I don't know what that means
But I left academia after my master's degree, if that's what you're asking
 
Did you left it for your own reasons? Or did you need a job urgently?
 
I left-its!
 
@Knight A bunch of reasons, but money was not the driving concern.
@Slereah You sure you're not looking at the price per page? :P
 
9:39 AM
@ACuriousMind Amazingly not!
I mean there's shipping, but even with shipping it comes at under 6 bucks
For some reason, the field of "Defining clocks in general relativity" uses a lot of Weyl spacetimes
which is weird and annoying
I guess it's simpler because of conformal symmetry, but I want real spacetimes dammit
 
I wanna light up the dark
Such a heavenly vieeeeewwwweweeweeeeeewwww
#bless
 
eewwwweweeweeeeeewwww
 
@Slereah Isn't Schwarzschild Weyl?
'Is Schwarzschild "not real" for you?
 
cbs.com/shows/hawaii_five_0/video/… I really wanna watch this but it's not allowed in my country :(
 
By "Weyl" I mean the weird GR theory that Weyl proposed in the 20's
With the Weyl potential
 
9:43 AM
Ah, nothing to do with "Weyl metrics"?
 
Weyl was a busy guy
It's the theory where you use conformal equivalence classes of metrics, and $\nabla_Z g = \psi(Z) g$
Where $\psi$ is the Weyl potential
And you have the gauge tensor $F = d\psi$
 
A, OA, OA, got me feeling drunk and high, SO HA, SO HAAAAAA
 
0
Q: Why does an oven burn out when all knobs are on?

El FleaI'm having serious trouble understanding this. If a fuse burns out when too much current is flowing through it, then how does turning on all knobs to their full setting burn out the wall-plug? Shouldn't turning on all knobs increase resistance as you're adding more components to the circuit? Can...

 
someone from the USA, pliz crack me hawai 5-0 episode 17 season 10
 
Why is it off-topic?
 
9:50 AM
@ACuriousMind Are those reasons too personal? Can’t those be talked about?
I didn’t mean money, I meant you thought of earning so that you could pay the loans
 
@Knight Since I had a scholarship, I'm in the happy position to not have to pay back any loan
 
@ACuriousMind Wow! Means if someone is good at studying then he/she needs not to pay the loans back in Germany?
 
How much is the scholarship? 20000 German Marks? Oh! Just joking you need not to tell.
Twam naam Kim?
 
@Knight Kind of, though the criteria for selection are usually not only "good at studying" and vary from one scholarship to another.
 
@JohanLiebert it's asking about the design of ovens. I did hesitate before voting to close, but ultimately I don't think it's a good question for the site.
 
9:57 AM
@JohanLiebert It's around what you'd get from the guaranteed loan plus a little bit extra in most cases.
And there haven't been any German Marks for decades, we're using the Euro :P
 
@ACuriousMind sorry. I searched for German currency on Google and it gave German Marks as answer so.
 
@Knight I talked about some of them around here
 
@ACuriousMind Please call an ambulance if you're having a stroke. Nice one! 😂
Did anyone saw the video that I posted yesterday?
 
@JohanLiebert I ‘m on mobile can you tell me what’s the year of that chat?
 
10:05 AM
@ACuriousMind What you do in your job? Do you fix severe, do you do programming or what?
 
@Knight Jan 16 2019
 
@JohanLiebert It’s nice
 
@Knight I write static analysis tools for ABAP code. That is, I write code that tells other programmers when their code is bad :P
 
@ACuriousMind Are you satisfied with what you do? Or do you aim for something better and striving for it every moment
@skullpatrol Pal are you here?
 
@Knight don't you know he is incarnation of Einstein, Feynman and.....
 
10:10 AM
@JohanLiebert Really? Did apostles of God told you that?
 
@Knight I'm pretty content right now - my work is not my life, but what I do at work is fun.
 
@Knight I am the GOD.
 
@ACuriousMind Did you ever wish of doing something great in field of Science?
@JohanLiebert GOD : Gardener of Detroit
 
GOD: GOD Of Destruction!
@Knight Hope that I didn't offend any of your religious views cause I don't have one.
 
I’m a religious man
I’m a religious man
 
10:18 AM
@Knight really? I was just joking.
 
I couldn’t see what you removed
@JohanLiebert no one is serious here
 
That was gif but since it wasn't working so I just removed it. Let me try again.
 
@JohanLiebert Was that monkey our Abhas?
 
 
2 hours later…
12:14 PM
@ACuriousMind I want to know if anyone who does Master’s degree 📜 become eligible of understanding all the researches going on or being done?
I mean if you look me, I cannot understand the discoveries in Quantum Theories because I don’t know Hilbert Space, I cannot understand the stuffs in General Relativity because I don’t know higher dimensional Tensor Analysis. So, does everyone become that much knowledgeable by the end of Masters so to understand almost anything in Science.
If you cannot tell about everyone, then please tell me about yourself. Is there anything which YOU cannot understand? If it is there then why you are unable to understand it.
 
No, you become able to understand a tiny fraction of it :P
 
Are you writing a reply?
@ACuriousMind Why are you not replying to me elaborately?
 
Because I don't really have anything more to say?
 
@ACuriousMind Why? Are you able to understand every research going on?
Every means things in your field that is QM
 
@Knight this type of reply is definitely not appropriate here
you are not entitled to responses
 
12:25 PM
@Knight I already answered your question
Asking it again will not change my reply.
 
but, that said
@Knight no
 
@EmilioPisanty @ACuriousMind What stops us? Is the mathematics or the scarcity of time?
 
I don't think there is anyone alive who can understand what's going on in cutting-edge research in physics
@Knight I appreciate that QM might feel like it is a reasonably confined subset, but it is still a very vast field
 
Emilio I saw you in a video given in your profile, you were explaining QM to students in some university
 
@Knight There is vastly more material having been created and being created than you could ever even read, let aloneunderstand, and understanding one tiny subfield will not make understand an unrelated subfield much easier.
 
12:28 PM
@Knight uh... no? I mean, there is a video, but it wasn't to students, it was at a technical workshop given to specialists
I would expect that it takes a full masters-level course to really understand the details of what I'm talking about there
 
Subfield here is not "QM" or "GR", it's stuff like "low-temperature condensed matter theory", "high-energy particle accelerator physics", "quantum field lattice simulations", to name just three that are sort-of "QM" and there's dozens if not hundreds more
 
I wanna know, if you look me now it’s the intellectual incapacity that prevents me from understanding high level things. What happened at you people’s level?
 
and that course would have to be specific to the subfield I work on (namely, the theory of strong-field light-matter interaction in atoms and molecules)
 
Are you doing research?
I think you are around 33 years old?
 
if you had someone who did an MSc "in QM" but it was geared towards e.g. condensed matter, high-energy physics, quantum chaos, cold atoms, etc., then they wouldn't really be able to follow along a detailed discussion
there's just too much material to read up on
@Knight that type of information is in my profile
@Knight and I'm definitely not going to answer that.
 
12:33 PM
@ACuriousMind Try to understand me, if I were to read some political philosophy book I might not be able to understand it because it requires so so much contemplation but I cannot understand GR because my mathematics and few things in between are absent. Reasons are different, what is the problems we get when we older at your age or Emilio’s
 
@Knight The problem stays the same, always: That in order to understand something you need to understand all its prerequisites.
There is no magical level of math and physics knowledge where "all research" suddenly becomes clear to you. Each subfield still has a mountain of prerequisite knowledge unique to it that you must work through.
 
@ACuriousMind @Knight or, in graphical form, prerequisites
(click the image to follow through)
 
Beat me to it :P
 
@ACuriousMind ;-)
 
For a brief time there it looked like the goose would update again, but it's been dead for a while again now
 
12:37 PM
I know
=(
at least LGS is still active
but it's pretty depressing stuff if you read too much of it
 
@EmilioPisanty Arguably, it would be nice if it went dark because the conditions it reflected no longer existed :P
 
So it all boils down to prerequisite, ha? But what prerequisite still remain after Masters? Can you please give me some examples?
 
4 mins ago, by Emilio Pisanty
@ACuriousMind @Knight or, in graphical form, prerequisites
↑ example
your question is too broad to answer
the prerequisites are specific to each individual field of study
the prerequisites that remain after an MSc will depend on the MSc
 
All the prerequisite given in that link of yours gets covered in UG only
 
@Knight no.
 
12:42 PM
So the best way to go for the research is to live with some old man who is doing the same, ha?
 
Typically, if somebody who just completed an MSc that was specifically constructed to teach a given subfield (i.e. a field of study as specific as 'theory of quantum simulators using BECs in optical lattices), then you'd expect them to be able to follow along with material from any cutting-edge research in that field, so long as it's presented in a way that's general to the field
i.e., the sort of presentation you'd have in a conference on the topic
but they would still need one or two years of dedicated work to really understand enough of the details to start making new contributions
@Knight no.
 
@EmilioPisanty Wow! Means something different from General Education
 
@Knight and that is surprising because.... ??
 
@EmilioPisanty Why? Your big message says exactly that
@EmilioPisanty It’s not possible:-) am I right?
 
I don't see any mentions of old men in any of Emilio's messages
 
12:45 PM
@Knight no it doesn't.
@Knight Of course it's possible. Thousands of people do it every year.
 
@ACuriousMind Well learning special topics in M.S. is same as learning it from an old man in that field
 
Neither old age nor male gender are necessary for competence!
5
 
@EmilioPisanty Does that type of course given in your country to anyone who wants it? As you must have been aware that in my country you require money and reputation for getting that kind of goal oriented MS
 
@Knight I don't know what your country is (nor do I really want to know)
 
@ACuriousMind nor the other way around
 
12:48 PM
@ACuriousMind just to emphasize: this. precisely this.
@Loong also this.
 
@EmilioPisanty Why you don’t want to know? It will make conversation better
 
dsm
@Knight Apart from 't Hooft's main website being endlessly entertaining, I recommend you look at this page of his.
 
@Knight I'm uninterested in talking specifics right now. tbh I'm getting pretty bored with this conversation and I have more important things to do.
 
@dsm Thank you :)
@EmilioPisanty I too don’t want to talk to someone who thinks I’m asking irrelevant things
 
dsm
np
 
12:51 PM
@Knight It's not that you're asking irrelevant things, it's that you don't seem interested about the actual answers and you're pretty dismissive of the things I'm saying, so I don't see much point in continuing to say them.
 
I was talking to ACM and you jumped in and now you left with harsh remarks
 
@Knight You simply seem to reply to things that we're not actually saying (cf "old man", asking for specific prerequisites when you've been told it varies highly between fields).
If you don't listen, don't be surprised that people stop talking.
2
 
@ACuriousMind I’m used to you, you can be rude to me.
I don’t take it that deeply now
 
It would be nice if you tried to make people not want to be rude to you.
 
Same applies to you too
Being rude is a trend here
 
12:56 PM
But if you keep asking questions without really engaging with previous answers, that's not conducive to a constructive conversation.
 
Can we go back to that conversation once again?
 
6 messages moved to Trash
As I said, let's not go there.
 
@ACuriousMind thank you
 
So, ACM what prerequisites still remain after M.S. ? Mathematical prerequisites or what?
 
28 mins ago, by ACuriousMind
There is no magical level of math and physics knowledge where "all research" suddenly becomes clear to you. Each subfield still has a mountain of prerequisite knowledge unique to it that you must work through.
The prerequisites there are all the important work that's been done in that field since its inception.
 
1:03 PM
There you go
Your last line is amazing
You know same happened to me when I read Bertrand Russell’s “Introduction to Mathematical Philosophy”
ACM and Loong I need your advice in one thing. I was thinking of learning German because many important Physics and Mathematics Text are written in German and I don’t why but I feel like the English translation somewhat takes away the real feelings of the original author.
 
I get that for fiction books, but for non-fiction I don't really think reading in the original is that important if translations exist.
It's also only mostly the old texts that are originally German, all newer material is usually English.
 
I’m talking about older texts only
Heisenberg’s you see, the English translation of his “Physicsl Principles of QM” takes away all the feelings from it.
 
That may be, but I neither see why you'd need "feelings" for a physics text nor why you'd read Heisenberg instead of a modern exposition of QM except for historical curiosity.
 
Because Ramamurti Shankar is ... you know
As far as feelings are concerned, sometimes author assumes that reader knows “this” and that “this” is very hard to know from translated texts.
 
I haven't read Shankar's QM book but your choice is certainly not only Shankar or old texts...
See physics.stackexchange.com/q/33215/50583 for a bunch of recommendations
 
1:17 PM
I’m of view that one should really read original discoverer (if notational things are not the barriers)
 
A nice sentiment, but as an introduction I doubt the usefulness - usually our understanding will have evolved in the intervening years and the old account will of course not reflect how people today look at it.
I've heard that Dirac's book on QM holds up nicely but I've never heard the same about Heisenberg's, probably for a reason :P
 
:D
It may be because of Bohr
@ACuriousMind No not as an introduction but after some familiarity
So according to you, whether I will get something by learning German? By “get” I mean getting some insights in the field of physics
 
1:36 PM
For relaxing times, make it Suntory time.
 
I'm reading a book called Buyology. It's very cute.
 
 
1 hour later…
dsm
2:47 PM
@ACuriousMind you around?
The bar is closing and I have to change locations, so I'll post my question anyways. I'm reading a proof showing the tensor product representation of an orthogonal or Lorentz group $G$ with metric $g$ on antisymmetric 2nd rank tensors coincides with the adjoint representation on $\mathfrak{g}$. $L$ is defined in the usual way as the intertwiner between $\mathbb{R}^n$ and $\mathbb{R}^{n*}: v\mapsto g(v,\cdot),$ and the intertwiner $\phi:\Lambda^2\mathbb{R}^n\rightarrow\mathfrak{g}$ is defined as
$$\phi(T)(v,f)\equiv T(L(v),f)\hspace{3mm}v\in\mathbb{R}^n, f\in\mathbb{R}^{n*}, T\in\Lambda^2\mathbb{R}^n$$
The line in the proof I'm not understanding is
$$g(\phi(T),v,w)+g(v,\phi(T)w)=\phi(T)(v,L(w))+\phi(T)(w,L(v)).$$
What happened to $g$?
Oops, the first $g$ should read $g(\phi(T)v,w)$. Misplaced a comma
 
@dsm I don't understand your definition of $\phi$. $\phi(T)$ is an element of some algebra $\mathfrak{g}$ - how am I supposed to apply that to a a pair of co-vectors ($v$ and $f$)?
 
dsm
3:12 PM
@ACuriousMind $\mathfrak{g}$ is a vector space of linear operators, so the elements can be interpreted as $(1,1)$ tensors
 
So you're taking $\mathfrak{g}$ as being the matrix algebra instead of an abstract one here, okay.
 
dsm
Keeping everything abstract, just a $(1,1)$ tensor
 
My point is that an "abstract" Lie algebra is not made out of (1,1)-tensors :P
You get that only if you think of it as a matrix algebra, whether you want to write the matrix components or not
 
dsm
I'm confused. Why is there any need to talk about the matrix algebra? $\phi(T)$ is a bilinear function on $V\times V^*$
 
@dsm given a Lie algebra $\mathfrak{g}$, you do not have in general that its elements are (1,1)-tensors on something. And even more, if you define $\mathfrak{so}(n)$ purely abstractly by its commutation relations, you also don't get that
You only get that if you realize that $\mathfrak{so}(n)$ "are" n-by-n matrices on $\mathbb{R}^n$ and therefore act as (1,1)-tensors on it
 
dsm
3:18 PM
Hmm, how do you interpret the following sentence in my text before defining this intertwiner: "To define $\phi$ abstractly we interpret $\mathfrak{g}$ not as a space of matrices but rather as linear operators on $\mathbb{R}^n.$"
 
linear operators on $\mathbb{R}^n$ are matrices
Whatever distinction that sentence is trying to make is lost on me, except maybe that they're saying they don't want to pick a basis, i.e. talk about matrix components in a particular basis.
 
dsm
I think that's exactly what he's getting at, not choosing a basis
For that equation I'm confused about, the only justification given is "by definition of $L$"
 
@dsm Maybe this helps: $g(v,w) = L(w)(v)$ and $L(w)(\phi(T)v) = \phi(T)(v,L(w))$.
The first is "by definition of $L$" indeed, the second is more or less "by definition of a (1,1)-tensor", together these are all you need to get from your l.h.s. to the r.h.s.
 
@Loong Sir was it for me?
 
dsm
Working it out, one sec
Ok, I can see that. And to clarify, you are pulling out the $\phi (T)$ from linearity of the inner product, and then denoting the abstract dual with $L(w)$? Otherwise it's kind of weird notationally: $(v,L(w))=(v,(w,\cdot))$
 
3:41 PM
No, I'm saying that applying the covector $L(w)$ to the vector $\phi(T)v$ is the same as applying the (1,1)-tensor $\phi(T)$ to the pair of vector/covector $(v,L(w))$
 
How could someone justify the assumption "The interaction takes place at the nuclear surface only" for Surface Delta Interaction schematic interaction in nuclear physics?
 
Because the vector $\phi(T)v$ is by definition the vector defined by $\phi(T)(v,\cdot)$ ($\cdot$ being a covector slot) and applying the covector $L(w)$ to that vector is by definition just slotting the $L(w)$ in there.
 
Alternatively, why the kinetic energy should increase in the interior of the nucleus than at the surface?
whereas, the interaction potential is stronger at the surface and weaker at the interior.
 
dsm
So changing the direction of your slots to represent a vector as a $(0,1)$ tensor, is the following chain correct: $L(w)(\phi (T)v)=L(w)\phi(T) (\cdot,v)=\phi (T)(L(w),v) = \phi (T)(v,L(w))$?
I see you're jumping to it because it's probably clear, but the steps aren't yet obvious to me
 
I don't see why your second expression has the $v$ in the second slot
You defined $\phi(T)$ to have its first slot as the vector slot and the second slot as the covector slot.
 
dsm
3:56 PM
Ah, I see, oops. I guess I'm confused on how you immediately know that applying $L(w)$ to $\phi (T)v$ is the same as applying $\phi (T)$ to $(v,L(w)).$ Is that obvious?
 
If I say 'yes', does that help you? :P
 
dsm
Haha no XD
 
So, do you agree that $\phi(T)v(\cdot) = \phi(T)(v,\cdot)$ if we think of the vector $\phi(T)v$ as a map $V^\ast \to \mathbb{R}$?
 
dsm
I can get on board with that
 
For any vector $x$, we can think of it as such a map $x(\cdot)$. Now, applying a covector $y$ to $x$ as $y(x)$ is the same as $x(y)$, we're just switching the notation around.
 
dsm
4:02 PM
Solid, still on board
 
And...that's all that happens here :)
$L(w)$ is the covector $y$, $\phi(T)v$ is the vector $x$.
 
dsm
Ahhh, ok, I see! That was confusing me. Appreciated :)
 
 
2 hours later…
6:18 PM
Sup im in an argument that i honestly cant understand their viewpoint in
They argue that particle phys is a branch of astrophysics
opinions? It seems ridiculous to me but maybe im a brainlet
 
@Phase What are their points for supporting themselves ?
 
@Phase Dmckee would have helped you
 
On what side of the moon these astronauts have landed? Seems like the one facing the sun (due to light there).
 
6:29 PM
Ill try summoning the wise one
@ACuriousMind i beseech thee
 
You shouldn’t ping him
 
@Phase I'm fully with you that I don't understand how they got to this belief in the first place.
Can't reason someone out of a position they didn't reason themselves into, so... :P
 
also how you been
you still a traitor computer man or did you go back to phys?
Ok so their argument is
"Astrophysics is the study of everything in the universe, and they also study small phenomena. Particle physics is therefore a branch of astro"
essentially
 
@Phase I'm alive and well enjoying the life of a traitor - I assume you're still trying to become a brave little physicist? ;P
 
I actually swapped to maths because i just couldnt study the modules in physics that i hate, made me big sad
astronomy and lab work be horrid
 
6:34 PM
@Phase Ok, so everything is astrophysics. They've just defined astrophysics = science
 
yeah i basically said to them "so whats the point of physics then"
 
Doesn't really seem like a "viewpoint" I'd bother to debate in any more detail :P
@Phase Planning to stay in maths or planning to do physics with it and you're just bypassing the lab work?
 
they seem to see it the same way as you do xd
Hopefully gonna go into theo phys or something after
idk pure maths is fun to learn but i dont think i have the galaxy brain required to actually produce new things in it
 
I'd have thought it's (astro)physics you'd need a galaxy brain for :P
 
Hello everybody!
I have some questions about Newtonian World Index Algebra.
Can someone help me, please? (My questions are elementary level)
 
6:40 PM
Just ask your questions, if someone can and wants to answer them, they will (but I'll say right off the bat that I have no idea what "Newtonian World Index Algebra" is)
 
top right bro
dont ask to ask, ASK
They're quoting me now and claiming that im laughably wrong, the quote they're ridiculing right now is "Astrophysics is a branch of physics, it is not particle physics nor is it theoretical physics, because they're all concerned with different things" lol
altho tbh it does seem a bit reductive in hindsight idk how to phrase it better tho
oh also ACM is your pfp disco elysium?
 
6:59 PM
Yep :D
 
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