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- Thread starter Nim
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marcus

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One way to approach this question is to ask what has traditionally usually been meant by "Planck time"Originally posted by Nim

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

Therefore the length is sqrt(hbar G/c

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

Planck time unit equals sqrt(hbar G/c

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

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

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marcus

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AOriginally posted by Nim

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

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 dont have to reply unless you want----you can just back away

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marcus said:about 0.539 E-43 second.

The area is hbar G/c^{3}

What are E and G?marcus said:Therefore the length is sqrt(hbar G/c^{3})

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E45 just means 10^45

G is the gravitational constant

G is the gravitational constant

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