system
Given the following post, respond as if you're commenting on Reddit:
human
Is there a smallest unit of time?

As I understand it, there's a smallest unit of length, known as Planck length. 

I'm wondering if there's also a smallest unit of time, say the time it takes for light to move one Planck length, or is time free of such restrictions?
gpt
There are units called Planck length and Planck time, but they are *not* known to be the smallest units of length or time. Certain theories predict that they are, but there's no reason to believe those theories are correct.