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4:00 PM
Um...'rock hard' probably has a different connotation in English than what you intended there :P
 
@ACuriousMind means?
 
@dumbasarock Happy to be here but no need to call the curse of my existence a blessing ;P
@AbhasKumarSinha just google "become rock hard" and I think the results should speak for themselves...
 
HAHAHAHAHAHAHA....
Oh my god...
Why that happens with me only ? :P
I'm signing off... Bye
 
@ACuriousMind I've always wanted to ask, is this you on the picture (no offense)
 
Jan 17 at 18:02, by ACuriousMind
@Knight It's the protagonist of Disco Elysium
 
4:06 PM
coolio
I like this google.com/…
If I had to express myself through an avatar, it'd definitely be my Jeff Goldblum with his gorilla
 
dude I am one of those fanboys of physicists
if I see one even remotely close to being prodigy he/she deserves my respect
your existence is blessing
that reputation of yours evident of how many of curious minds has your "curious mind" helped in fathoming the physics it speaks for itself
 
@dumbasarock I agree
 
@NovaliumCompany you should
 
@dumbasarock I should and I do, because no matter how difficult and annoying I sometimes get, this person hasn't yet given up on me. I truly appreciate that. His life is a blessing, to me and many others.
 
stack exchange is blessing upon us.
definitely for us Indians we thrive on these platforms to succeed.
I am sure if mobile app for stack exchange had been updated
many dormant minds would have left instagram and looked for real beauty
WHICH IS HERE
 
4:20 PM
@PhysicsMeta saving these here in case they become relevant
15
Q: Access to journals for individuals outside of an institution?

dianovichFor all that is said about the wealth of information that is freely available on the internet, the fact is that most of it is incomplete, dumbed down, lacking in context or downright wrong. Individuals spend the best part of 20 years completely oblivious to the existence of journals and the pro...

24
Q: What do you do when you find yourselves with an unreadable/inaccessible paper?

Leon palafoxSince I started my life in Academia, I sometimes found that there are some seminal papers to which I cannot get any access. Either they are very old, and the journal that published them charges for it, or they are simply not to be found anywhere in the internet. I have to admit I never went to ...

28
Q: Ways to get free and legal access to research papers as a researcher

ReviousI’ve discovered that website like ResearchGate offer the possibility to ask the paper editor to provide his paper for free. Many are collaborating. Are there any other ways for researchers to obtain free access to papers?

13
A: Ways to get free and legal access to research papers as a researcher

VonBecheThe website mentioned here is obviously and blatantly illegal, but gives access to almost all journals ever published. It's very easy to use and more complete than our direct subscriptions. I might almost use it for stuff I have legal but slow access to. Use or do not use depending on your view...

 
@dumbasarock yes i'm definitely an indian
 
@NovaliumCompany by "us indians" I meant abhas and fake mod
 
@dumbasarock Thanks, I guess? But I'm just one of many users here, don't focus too much on me. And to maybe take this far too literally, I don't think these users are divine gifts. You're free to believe otherwise but to me they're just humans helping other humans out of their own free will, which is far more awesome.
 
@ACuriousMind "humans helping other humans" how often do you see that these days that trait is worth being respected
@EmilioPisanty "Sci-Hub was founded by a Kazakh humanities researcher, Alexandra Elbakya, and has tens of thousands of daily users, many from places like Russia and India."
fellow Indians doing illegal to gather knowledge impressive
 
4:28 PM
@dumbasarock I'm pretty busy. If you have a specific point or request, then please do so concisely.
Apologies but I cannot engage in general discussions at this time.
 
I am sorry for the ping
 
@dumbasarock Thanks :-)
I've a question...
$$ \frac{\partial X^T}{\partial X} $$
 
@AbhasKumarSinha for me ?
 
What's it?^
@dumbasarock anyone, if you know the answer please consider helping
$X$ is a matrix of $n \times n$
@dumbasarock that's T stands for transpose
maybe I should ask in Maths chatroom....
 
@AbhasKumarSinha You cannot just write down an expression that differentiates by a matrix and expect it to be well-defined. Ordinary differentiation works on functions of a single real (or perhaps complex) variable. You have to first define what you mean for it to be meaningful.
 
4:36 PM
@ACuriousMind Differentiation with respect to matrix exists...
@ACuriousMind in linear algebra...
In mathematics, matrix calculus is a specialized notation for doing multivariable calculus, especially over spaces of matrices. It collects the various partial derivatives of a single function with respect to many variables, and/or of a multivariate function with respect to a single variable, into vectors and matrices that can be treated as single entities. This greatly simplifies operations such as finding the maximum or minimum of a multivariate function and solving systems of differential equations. The notation used here is commonly used in statistics and engineering, while the tensor index...
 
@AbhasKumarSinha So what's your definition of $\frac{\partial}{\partial X}$ here and what problems do you have in applying it to $X^T$?
 
@ACuriousMind I don't know what are you asking, derivative with respect to a vector means, you gradient with respect to a matrix.
like we know $$\frac{\partial X^T X}{\partial X} = 2 X$$ for $X$ of order $n \times n$
 
4:55 PM
@ACuriousMind this - en.wikipedia.org/wiki/…
 
Linking a section on vector-by-vector differentiation as your definition of a matrix-by-matrix differentiation is not very helpful.
 
@ACuriousMind matrix by scalar and scalar by matrix then chain rule to get matrix by matrix.... (probably, I guess)
 
It seems to me you should first work out what your expression is supposed to mean before you ask other people what its value is.
 
Where is this matrix differentiation stuff used
 
@bolbteppa Machine Learning...
You know Machine Learning?
 
5:00 PM
Nope
 
oh okay...
@ACuriousMind seems, that's wrong to me too....
 
What?
 
@ACuriousMind It's wrong... confirmed with Wolfram-alpha... I'd have to search some other alternative.
 
You're being incoherent again. What is wrong? What did you confirm? What has any of this to do with you not being able to even define the meaning of your expression?
 
Expression is wrong
I confirmed that derivative expression is invalid and means nothing.
@ACuriousMind leave it, the expression is wrong itself, so no results.
 
5:08 PM
So you smugly cited Wiki articles at me only to now have magically confirmed that you didn't know what you're talking about in the first place. 'kay. For the record, this is not behavior that would motivate me to respond to a question of yours in the future.
 
@ACuriousMind The wiki was talking about vector and I was talking about matrix... as I said that expression is totally wrong, there exists no meaning itself, although derivative wrt Matrix exist which I've shown you (in the wiki too) but in such cases, it yields no meaning, totally wrong expression, you can ignore that. My fault, sorry, totally my fault.,
 
 
1 hour later…
6:29 PM
I want to apologize for earlier where I started a debate on topics I have no clue about. I understand how frustrating it may be to debate with someone who clearly is not educated on the topic and yet attempts to make conclusions.
 
 
5 hours later…
11:16 PM
does anyone here know good places to intern for expertise in quantum technology? e.g. spintronics, quantum computing, exotic materials etc. To be available internationally of course.
 
11:55 PM
Aaaah
It's too late to deal with the jet bundle
 

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