Measures on infinite dimensional spaces?

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I am looking for a measures on an infinite dimensional space. In the process I came across the theorem structure theorem for Gaussian measure. The link for the theorem: https://en.wikipedia.org/wiki/Structure_theorem_for_Gaussian_measures

As I understand I have no other option but to stick to Gaussian measure. I want to have an intuitive idea why only Gaussian measure ( I did not quite the understand the proof, too mathematical) is possible. Any comments would be highly appreciated.

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Depending on the space, measures may be fairly easy to come by. For example, if $B$ is any separable Banach space, let $\{a_n\}$ be a countable dense subset. Then define, for any $E\subset B$, $$\mu(E)=\sum_n 2^{-n}\,\delta_{a_n}(E),$$ where $\delta_{a_n}(E)=1$ if $a_n\in E$, and zero otherwise. Since weighted sums of measures are measures, $\mu$ is a probability measure on $B$.

Of course, any other set of weights may be used.