Comment by shrx
3 days ago
Fiber optic strands are glass rods (solid interior) instead of tubes (hollow cylinder). The two shapes have different strength properties per unit mass [1, 2].
[1] https://physics.stackexchange.com/questions/12913/hollow-tub...
[2] https://www.mtbiker.sk/forum/download/file.php?id=207637
Traditionally, yes.
Hollow air core fibre does exist and seems to be touted as the next big thing though.
https://www.optcore.net/hollow-core-fiber-introduction/#h-wh...
Current implementations break from simple vibrations such as a bus driving down the road and shaking the ducts the fibre is in. Lots of work required still. Crazy expensive and crazy fragile.