I recently read some books about General Relativity, and how the "3-Brane" of standard spacetime is curved through the higher dimensional "hyperspace" of "The Bulk" (to use some String Theorist terms, as I've been told them). One of the books suggested that standard spacetime, which is like a thin sort of "shell" curving through hyperspace, could conceivably have some sort of "hyperspace thickness" -- and, that this thickness could account for things like the Pauli Exclusion Principal. For example, electrons might be "half as hyper-thick" as spacetime, so that you could "stack" two of them "over" each other, in the same stretch of space. Conversely, photons might be very "hyper thin", so that many can pass thru the same stretch of space simultaneously.

 

Likewise, the book Intro. to Mod. AstroPhys., by Carroll & Ostlie, stresses that the "Big Bang" has actually been much more like the "Big Stretch", and that spacetime has stretched considerably since its inception billions of years ago.

 

Now, naively, when anything "stretches", it inevitably "thins" (e.g., Stress-Strain tests in engineering). And, the "thinner" that the 3-brane of standard spacetime becomes, the fewer electrons can "squeeze" into some stretch of space.

 

So, consider some time period back billions of years ago, when spacetime was significantly less stretched, and so was twice as "hyper thick". Conceivably, then, the Pauli Exclusion Principal could have allowed twice as many -- to wit, four (4) -- electrons to "stack" in the same space. Is there any evidence for, or against, this ??

I suspect you need a quantum theory of gravity in order to address his.