Any rotation about n(θ, φ) in SU(2) can be represent as(adsbygoogle = window.adsbygoogle || []).push({});

u(n, ω) = I cos[ω/2] - i(σ.n)sin[ω/2],where I is the unit matrix and i is the complex number.Right?

But can someone tell me why ω/2 rather than ω?

Waiting for your response.Thank you.

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# A question about SU(2)

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