How does string explains pair creation and annihilation ?
By string splitting.
In the first place, vacuum has nothing, only fields. I don't see how strings could suddenly pop out of nowhere? Sorry, just new in these things.
In the true vacuum, there is no pair creation. If there are fields, then it is NOT nothing, not a true vacuum. Furthermore, a field has its source. For example, a source of a static electric field is a charged particle. Now, in string theory, the pair of strings is created from the charged source string.
I wouldn't disagree more. It's better we say there is no true stationary vacuum. From what we know of fluctuations even when we consider a space or point mass momentarily at rest, we can say argue that the vacuum itself is fluctuating. The fluctuation creates energy and we all know particle pairs or "string" as in the stirng theory could be created out of energy brought on by this fluctuation.
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