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Timeline for Tensor Operators

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Apr 2, 2015 at 18:17 answer added tensorman timeline score: 7
Jul 25, 2014 at 1:08 vote accept joshphysics
May 10, 2014 at 19:21 answer added ZeroTheHero timeline score: 1
Oct 14, 2013 at 20:55 answer added Qmechanic timeline score: 14
Oct 10, 2013 at 9:11 answer added Frederic Brünner timeline score: 1
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Sep 8, 2013 at 12:36 answer added David Bar Moshe timeline score: 0
Sep 8, 2013 at 6:57 answer added xuanji timeline score: 0
S Sep 8, 2013 at 5:55 history bounty started Manishearth
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Aug 9, 2013 at 3:22 history edited joshphysics CC BY-SA 3.0
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Aug 8, 2013 at 19:12 comment added joshphysics @Trimok Would you agree that we can define a tensor operator in the way that I did? If so, then it's simply a generalization in which $\rho$ is not restricted to be any representation of $G$. That's kind of the point of the definition I'm trying to make here in fact. I think this generalization is important, because in QFT for example, we might be inclined to consider objects whose indices transform in representations other than some vector representation.
Aug 8, 2013 at 18:59 comment added Trimok Second chance....But isn't $\rho(g)$ always (if it exists) the fundamental (vectorial) representation of the group $G$ ?. I do not understand your proposal with another representation, while I probably missed some point....
Aug 8, 2013 at 18:20 comment added Peter Kravchuk I just want to note that your definition is a bit too high-level, may be. In the sense that what you actually do is: you pick a representation $\rho$, then you 'tensor' it to the representation $\tau$ acting on tensors, and then define an object that is associated to $\tau$ rather than $\rho$. You could as well start with $\tau$. It seems to me that it is also usefull to think of 'linear object valued operators', the elements of $\mathrm{Hom}(\mathcal{H},L\otimes\mathcal{H})=L\otimes\mathrm{Hom}(\mathcal{H},\mathcal{H})$, where $L$ is a vector space acted upon by some representation $\tau$.
Aug 8, 2013 at 17:59 comment added joshphysics @Trimok Thanks for the comment, but this is not intended to be a question on tensor representations of groups, but rather a question on the notion of a "tensor operator" on a Hilbert space, its formalization, and the existence of existing mathematical literature on such things.
Aug 8, 2013 at 16:42 history edited joshphysics CC BY-SA 3.0
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Aug 8, 2013 at 7:25 comment added Trimok For $SU(N)$, there is a direct link with fundamental representations and antisymmetric tensors. Idem for $SO(N)$, (not considering spinorial representations). (Note that they exist duality between these representations thanks to the Levi-Civita symbol) For $SP(N)$, there is a direct link with fundamental representations and symmetric tensors. Of corse, extending to all representations, you may gain correspondence with other tensors. For instance, the adjoint representation represents a mixed tensor $T^i_j$. For SU(N), representation $(20....)$ represents a symmetric traceless tensor.
Aug 8, 2013 at 5:54 history tweeted twitter.com/#!/StackPhysics/status/365350336526950400
Aug 8, 2013 at 2:06 history asked joshphysics CC BY-SA 3.0