Stupid Speed of light question

[physprof]

Eighteeteewhy said:

What about if it was made of these carbon nano tube things?

Nope. Light is still slower - simplistic but think of matter as viscous medium (that was where the 18th century forays to relativity started) with light passing through an ether) - and the light would have to speed up (accelerate) upon entering it... where does the extra oomph (energy) come from...? Also no point speculating - got to do the experiment.