How do E Folds relate to real distance?

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E-folds provide a measure of the universe's expansion, indicating that one e-fold corresponds to an expansion by a factor of e (approximately 2.71828). The discussion raises questions about the relationship between e-folds and "real distance," particularly in the context of horizon growth during inflation. It is suggested that while e-folds quantify expansion, their direct correlation to physical distances may not be straightforward. The concept emphasizes that all distances between comoving objects increase uniformly with each e-fold. Understanding this relationship is crucial for comprehending cosmic inflation and the dynamics of the universe's expansion.
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How do E Folds relate to real distance?
 
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e-folds number is giving you a measure of the expansion ...
I am not sure if they will in general relate to any real distance (what do you mean by real distance?)...maybe with the Horizon growth during inflation...
 
One "e-fold" means the universe has expanded by a factor of ##e## (the base of natural logarithms, 2.71828...), so all distances between comoving objects have increased by the same factor.
 
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