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can it be a definition of G in a string theory ?

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cf the pdf join

 

my problem is the dimension of G

 

thank you for yours answers

G.pdf

Edited by stephaneww

From PDF (which we would prefer you post in abstract on the site)

 

G is the current gravitational constant G = 6, 67384 kg m s1

 

Well

 

F=GMm/r^2

 

 

So if we look at that in base units/dimensions you get

 

[kg][m]^-2 = G [kg]^2[m]^-2

 

divide both sides by kg^2

multiply both sides by m^2

 

and you get

[m]^3 ^-2 [kg]^-1 = G

 

you can even sub in the defintion of Newtons

 

[N] = G [kg]^2[m]^-2

 

and get

 

G = [N][kg]^-2[m]^2 which is the SI units for G

 

So no - you are incorrect. getting Newtons grav constant dimensionally wrong in a paper on gravity is not cool

!

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Do not respond to this in the thread

Newton's constant is not fundamental in string theory, it can be calculated from the string tension and the dilaton. The only free parameter one should have in string theory is the tension.

  • Author

just noticed the value of G is given incorrectly in your paper as well. It is too big by a factor of a hundred billion

it' noarmal in this paper i have made an error on the age of universe : its not in seconde but in billions year. it's the mistake.

 

in seconds i'ts 4,354 * 10^7

 

thank you

Edited by stephaneww

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