Newton's Constant Help: Kainaan's Question

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Kainaan, a 14-year-old physics enthusiast, seeks clarification on Newton's constant (G) and its significance in the context of the Schwarzschild radius. G is a measure of gravitational strength, and while it is a constant in our universe, discussions can explore hypothetical scenarios where G has different values in alternate universes. In such imagined universes, a larger G would result in stronger gravity, while a smaller G would lead to weaker gravity. The conversation emphasizes understanding G's role in theoretical physics and its implications for the behavior of matter and energy. Overall, the discussion successfully clarifies Kainaan's initial confusion about the nature of Newton's constant.
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Hello my name is Kainaan i just joined this forum, I am 14 and i love every related to physics, i study quantum hysics and general relativity. I have a question about Newtons constant, i have been reading on the Schwarzschild radius and came across the equation for it, in the eqaution it has the variable G which stands for Newtons constant, i understand all of the other stuff in the equation and i know what Newtons constant is (6.7 x 10 to the -11), but i don't understand what it means like what it is.

if you could please explain it to me that would be awesome, i hope to talk to you all about other physics topics in the near future.
 
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In some sense, G is a measure of the strength of gravity. If G were larger, gravity would be stronger; if G were smaller, gravity would be weaker.
 
but isn't G a constant and therefor always the same, so i can not be larger or smaller its just always the same thing.
 
Last edited:
Kainaan said:
but isn't G a constant and therefor always the same, so i can not be larger or smaller its just always the same thing.
Yeah, but you can imagine a different universe where the constant takes a different value, and figure out how the behavior of matter and energy would be different in that universe. Although, there are problems with talking about changes to values of non-dimensionless constants like G or the speed of light...see the discussion here, and see here for a list of dimensionless constants (all particle masses can be made dimensionless by dividing by the Planck mass).
 
Kainaan said:
but isn't G a constant and therefor always the same, so i can not be larger or smaller its just always the same thing.

Right. The idea is to imagine universes that have different values of G than the value of G that we measure in reality.

If in an imaginary universe G is larger than what we really measure, gravity in the imagined universe would be stronger that it is in our universe; if in an imaginary universe G is smaller than what we really measure, gravity in the imagined universe would be weaker that it is in our universe.

Edit: JesseM was faster.
 
ok now i understand thanks for the help
 
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