I was reading some introductory stuff on various websites about the string theory of quantum gravity which postulates that among other things-

http://www.strings.ph.qmw.ac.uk/WhatIs/what.html

“What string theory does is to replace the point particles of QFTs with extended 1-dimensional objects, strings, with length of the order of 10^-33mm, termed the ‘Planck length’. What one is then dealing with is a QFT on the 2-dimensional ‘world-surface’ of the string as it moves through time, embedded within spacetime itself. The first effect of this is to ‘smooth out’ interactions in such a way that UV behaviour remains finite. Also, one finds that such a theory can be used to describe gravitational interactions in an entirely natural way.”

I have not found anything on these sites as to why a “Planck Limit” object makes intuitive or empirical sense as the mediating, 10 dimensional sub-quantum ether through and by which electromagnetic, weak and strong nuclear force and gravitational interactions take place. It’s almost as if they are saying “Well the math works pretty well with strings so were going to pretend it’s true for now.”

Obviously this take on the subject is wrong headed or so many math and science geniuses wouldn’t be tackling the work involved in parsing out a deci-dimensional “theory of everything”. Barbie was right - this math *is* hard.

So why little Planck length strings? Why must or should these exist other than enabling equations to close properly?