I saw something about a runner being disqualified because they moved 9 hundredths of a second after the gun. Ten hundredths is permitted but nine is not.
It’s not impossible to believe someone could be just a sliver faster.
Ten hundredth is what’s impossible plus a generous safety margin. If you are under it’s definitely a false start. If you are just over, it was most likely a false start but you were lucky this time.
It is extremely unlikely that a human being can hear a sound and move their foot within 100ms. Based on what we know of the brain and nervous system, it's most likely that anyone who reacts under 120ms has jumped the gun.[1]
In case anyone is curious, the starting times for the first five runners at the 110mH event at the 2022 World Championships were (in milliseconds) 99, 108, 109, 124, and 126.
While I personally disagree with the comment I am replying to regarding reaction times under 120ms, the issue at this World Championships was more likely that the reaction timing was wrong ...