My book states :
The scope of physics is truly vast. At one end, it studies phenomena at the very small scale of length (10^-14 m or even less) involving electrons, protons, etc.; at the other end, it deals with astronomical phenomena at the scale of galaxies or even the entire universe whose extent is of the order of 10^26 m. The range of time scales can be obtained by dividing the length scales by the speed of light : 10^–22 s to 10^18 s.
I cannot understand why we have divided length scales by speed of light to get time scales. Is it because light takes shortest time to travel a distance.
Please explain me the reason. Thank you in advance.