Is proportionality in log space valid? (Example: Bayes Theorem)

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For Bayes we can write

$$ p(X|Y) = \frac{p(X)\ p(Y|X)}{p(Y)} \propto p(X)\ p(Y|X) $$

in log space we can use the sum, for example when we want to calculate the maximum.

$$ argmax_k\ p(X=k|Y) = argmax_k\ \log p(X=k) + \log p(Y|X=k) $$


Question

Is there a way to formulate proportionality in log space as well?
Writing:

$$ [\log] \ \ p(X=k|Y) \propto \log p(X=k) + \log p(Y|X=k) $$

feels wrong with and without logarithm on the left side.