# is it possible to apply Newtonian physics at quantum gravity ?

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Hello

I would like to know if the following calculation is allowed in quantum mechanics or if it's only the definition :

$\Large{F_p=\frac{G*m_p*m_p}{l_p^2}}$

the numerical values are ok

Edited by stephaneww

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26 minutes ago, stephaneww said:

Hello

I would like to know if the following calculation is allowed in quantum mechanics or if it's only the definition :

Fp=Gmpmpl2p

the numerical values are ok

The equation is certainly "allowed". It might even be correct. It may be that a future theory of quantum gravity will give different results when the distance is comparable to the Planck length but we don't really know.

Note that the masses in your equation are very big compared to objects where we need to take quantum effects into account so it is probably only the distance that might cause problems with Newtonian gravity.

Also, you have labelled the force Fp but it is not the same as the Planck force: https://en.wikipedia.org/wiki/Planck_force

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Hello Strange,

of course "p" is for  "Planck"

I only try to find an element of quantum gravity for a context deterministic of quantum mechanics and submit it to a friend who works on this question

and as you say, it's not a usual way to approach the problem

22 minutes ago, Strange said:

...Also, you have labelled the force Fp but it is not the same as the Planck force: https://en.wikipedia.org/wiki/Planck_force

edit : do the calculation, numeric value and dimension are  ok

Edited by stephaneww

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10 minutes ago, stephaneww said:

oops do the calculation, numeric v

It seems like it is the same thing. It wasn't obvious!

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um, nothing new in fact, it's under keyhttps://en.wikipedia.org/wiki/Planck_units#Base_units

and it must be taken into account that:

$\Large{F_p=\frac{c^4}{G}}$

so, we can deduce that it takes at least a relativistic context
Edited by stephaneww

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mp can mean "mass of proton"

or

mp can mean "Planck mass"..

It's ambiguous.

(Planck mass is extremely big in comparison to mass of proton)

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3 hours ago, Sensei said:

mp can mean "mass of proton"

or

mp can mean "Planck mass"..

It's ambiguous.

(Planck mass is extremely big in comparison to mass of proton)

oops I missed that

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hum, I forgot to say that $_p$ is for Planck mass

Edited by stephaneww