Chronon & Planck's Time

[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.

 

[marcus]

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/c³

Therefore the length is sqrt(hbar G/c³)

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 c² inside the square root and get

Planck time unit equals sqrt(hbar G/c⁵)


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

10⁴⁵ Planck time units

 

[Nim]

Thanks for the answser.

This isn't a physics question. But how do you make those floating numbers like that 45 you have by the 10?

 

[marcus]

Originally posted by Nim
Thanks for the answser.

This isn't a physics question. But how do you make those floating numbers like that 45 you have by the 10?

A² is written like this (but with the spaces removed)

A[s u p]2[/s u p]


subscripts are written like superscripts except you say "sub"
instead of "sup"

if you want to see how anyone made a math symbol they wrote in their post, click on "quote" below their post AS IF you were going to reply and wanted to quote them in your reply-----you can look at how they typed stuff and you don't have to reply unless you want----you can just back away

 

[Mk]

about 0.539 E-43 second.
The area is hbar G/c³

Therefore the length is sqrt(hbar G/c³)

What are E and G?

 

[yxgao]

E45 just means 10^45
G is the gravitational constant