Hello, perhaps this is the most dumb question ever, but I don't see why it holds.(adsbygoogle = window.adsbygoogle || []).push({});

I'm looking at the irreducible representations of the Lie group U(1). To find them I considered the irreps of the lie algebra u(1). These irreps are obviously 1 dimensional and are given by f(a i ) = p a i for some real number p. If I now exponentiate this result I find that the irreducible representations of U(1) are given by g( exp(i theta) ) = exp(i p theta). But I read that p must be an integer. I cannot see however why this must be true! :(

Thanks in advance

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# Homework Help: Representations of U(1)

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