When Do Strings Or Membranes Begin?

[Silverbackman]

If strings or membranes are the most fundamental entity that cannot be divided further, where do these "particles" begin? Subatomic particles such as electrons, protons, and neutrons can be further divided into quarks, fermions, leptons, gluons, bosons, ect. Do particle physicists believe that these smaller particles (quarks, ect.) are directly made of strings/membranes? Or do they leave the possibility that strings/membranes can be many particles down?

And how far are we from being able to see these tiny membranes which are said to be 10^-20 of a millimeter? How long will it take to actually make a microscope powerful enough to see something this small (so that we can observe and prove it)?

 

[selfAdjoint]

If strings or membranes are the most fundamental entity that cannot be divided further, where do these "particles" begin? Subatomic particles such as electrons, protons, and neutrons can be further divided into quarks, fermions, leptons, gluons, bosons, ect. Do particle physicists believe that these smaller particles (quarks, ect.) are directly made of strings/membranes? Or do they leave the possibility that strings/membranes can be many particles down?

And how far are we from being able to see these tiny membranes which are said to be 10^-20 of a millimeter? How long will it take to actually make a microscope powerful enough to see something this small (so that we can observe and prove it)?

String theory does not itself say anything about the origin of strings or branes. Just as quantum theory does with particles, or quantum field theory with fields, it assumes them in being and sets out to describe their behavior.

As far as I know, string theory does not have a place in the usual account (confusingly called the "standard model of cosmology") of how the universe has fared since the big bang, if there was a big bang. There are string, or rather brane, accounts of a possible prior to the BB; one such is the ekpyrotic scenario, where two neighboring branes (whose origin is again not considered) every once in a while collide, causing a big bang-like phenomenon to happen in one of them.

In general "where things come from" is not a question well-fielded by any branch of the higher particle physics enterprise.