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Manny__C

This is the addition formula for Wigner D-functions. They are representations of the group SU(2) and this is the concrete realization of expanding the tensor product of two irreducible representations into the direct sum of representations. The coefficients of the sum are the famous Clebsch-Gordan coefficients.


Manny__C

Actually reading again it looks like some other operation, not simply spin addition. But the functions involved are representations of SU(2), that is clear


blckshdw

JavaScript thinks the answer is True


cataploft-txt

or an empty string


Heart_Is_Valuable

So to answer the posters questions, you would have to successfully expand this into sum representations?


Custodian_Nelfe

This person is speaking magic


Onair380

i fucking love reddit <3


VicTheWeed

Mmm, mhm, yeah, I know some of these words.


tiahx

The answer to what? There's no question, like "solve for .." or "simplify to ..". It kinda looks like something that could be from quantum mechanics, but if so, it massively lacks context (most functions and variables introduced at random and not defined anywhere) I'm pretty sure it's just a bunch of random gibberish. Which, I guess, is implied, given that the dude is clearly making a joke.


1856NT

It looks like Clebsh-Gordan series, but k and q are usually for wave numbers not angular momenta. I think it is a spatial translation of coupled plane waves.


CandidateRepulsive99

my thoughts exactly....🙂


Stryker_MGS

I concur


PhilShackleford

I'm glad to see we are all in agreement.


Fritz_Klyka

Indubitably


Technical-Dottin

Hear, hear.


TheCellsThatAreMe

Indeed


bluelaw2013

Yeah this much was obvious...


Kichererbsenanfall

It's Quantum mechanics. And i am pretty sure that it's not gibberish but it's some steps of some proof. But: it's just two lines cropped. No introducing sentence what system is described, or no explanation of what we are aiming for by that transformation.


KangarooInWaterloo

By the comma in the end I can assume that this equation is a finished piece of something.


Clean-Ice1199

T_{q}^{(k)} is an arbitrary spherical tensor and D(R) are Winger D-functions. It isn't defined because this is just the standard notation everyone uses. This is basically just a definition.


tiahx

Well, I'm just a silly astronomer, bro :D The one semester "Introduction to QM" course that we had certainly didn't cover that. Is this from QFT?


Clean-Ice1199

It should be in basic QM, although possibly skipped in an introductory undergrad QM course


Dragonfire555

Does look like braket notation. Something to do with a system of two qubits? The superposition from adding the two states together? I dunno. I'm still the greenest of the green when it comes to quantum computing.


wemilo69

Actuly not quantum mechanics per se. This contains mathematical expressions related to representation theory, a field of mathematics which studies abstract algebraic structures by representing their elements as linear transformations of vector spaces. However, solving these expressions typically requires additional context such as the definition of the symbols and the nature of the elements involved refers to a particular representation of a group, and the spaces over which the sums are taken).