Originally posted by Nim
What is the difference between a chronon and Planck's time? A few websites said they were the same thing. But other websites showed Planck's time as being smaller than a chronon. And those websites didn't always agree on how small Planck's time or a chronon is.
One way to approach this question is to ask what has traditionally usually been meant by "Planck time"
Planck proposed a set of natural units in 1899 to a meeting of the Prussian Academy and the time unit he proposed was
for practical purposes the same as what is called "Planck time" today----about 0.539 E-43 second.
For over 100 years the Planck time unit has been this.
What the "chronon" is must depend on whatever writer is talking. It is not a well-established traditional thing, so could mean anything someone wants it to mean. The basic string theory scale is not solidly nailed down so if there is a "chronon" in that context it could be drifting around changing from author to author.
Here is how to remember Planck units:
Memorize what the area is and get all the rest from that.
The area is hbar G/c
3
Therefore the length is sqrt(hbar G/c
3)
The unit time is how long light takes to go unit length so it equals unit length divided by c. Or you can divide by c
2 inside the square root and get
Planck time unit equals sqrt(hbar G/c
5)
Since Planck time is 0.539 E-43 second, if you multiply by E45 you get 53.9 seconds which is on same scale as a ordinary minute.
So next time someone on telephone says "please wait a minute. I put you on hold for a minute" remember that this means
E45 Planck time units, or maybe you like it better written
10
45 Planck time units