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We know that $\phi$, the golden ratio, is algebraic. Is it known whether $\log(\phi)$ is algebraic?

Thank you!

PS. I am not in number theory, so I apologize in advance if this is obvious.

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$\log (\phi)$ is transcendental. The Lindemann–Weierstrass theorem implies that if $\alpha$ is a nonzero algebraic number, then $e^\alpha$ is transcendental. So since $\phi$ is algebraic, $\log (\phi)$ is transcendental.

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    The trick is to have forgotten the statement entirely, so you have to look it up. – 2011-05-27