State of a Generator in Representation Theory

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Silviu
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Hello! I am reading something about representation theory (just started) and I encountered this: "We will denote the state in the adjoint representation corresponding to an arbitrary generator ## X_a ## as |## X_a ##>". What is the state of a generator in a certain representation?
Thank you!
 
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They did not talk about the state of a generator.
You have a generator... this can generate a state. They are introducing a notation to help talk about that.
Maybe you need to go back to find the definitions of "state" and "generator", and find out what a generator does?
 
Simon Bridge said:
They did not talk about the state of a generator.
You have a generator... this can generate a state. They are introducing a notation to help talk about that.
Maybe you need to go back to find the definitions of "state" and "generator", and find out what a generator does?
Thank you for your answer. I am still a bit confused. From what I understood generators are part of the Lie Algebra and they can generate the whole Lie Group. For example for SO(2) if S is the generator any rotation by ##\alpha## degrees is written as ##e^{i\alpha S}##. So, I understand a generator generates a whole group which usually acts on a vector space. Please let me know if anything I said is wrong. Now, I just don't understand where the idea of state appears in this as I thought that generators are generating a group not states.
 
I get confusded too and authors can use the same word to refer to slightly different things.
I do not have the context of the passage - but I would see the above as meaning that |A> is a single state belonging to the group that is generated by A.
The passages that follow should include examples that will make the matter clear. If they do not, then get a different book.