Infinite cardinal comparation

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Let $\alpha$ and $\beta$ two infinite cardinal numbers.

Can we have $\alpha = \beta^\alpha$?

This problem comes from a situation where I am dealing with the cardinal of a set of functions.

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No, we cannot. Cantor's diagonalization argument shows that $\alpha<2^\alpha,$ and it is readily apparent that $2^\alpha\le\beta^\alpha$ for any $\beta\ge 2.$