All Questions
5
questions
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128
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Do we really know the universal gravitational constant?
We've all heard $$F_g=\frac{gm_1m_2}{r^2}.$$ However, since I took physics, we've discovered "dark energy," which if I have any concept of the current thinking is caused by space being ...
3
votes
1
answer
115
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Understanding calculation in Feynman's Lecture on Theory of Gravitation about age of universe and gravitational constant
I am reading Feynman's Lectures. In the chapter entitled "The Theory of Gravitation", there is the following part
If we take, in some natural units, the repulsion of two electrons
(nature’s ...
- 311
-1
votes
1
answer
62
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What are $δ$ and $ε$ in the list of Dirac's five 'fundamental constants', concerning his 'Large number hypothesis'?
From Jean-Philippe Uzan's Varying Constants, Gravitation and Cosmology:
Dirac formed five dimensionless ratios among which1 δ ≡ H0ħ/mpc2 ∼ 2h × 10−42 and equation M1 and asked the question of which of ...
- 4,509
3
votes
1
answer
498
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Dicke's variable speed of light proposal and his refractive index formula
As far as I understand Wikipedia, Robert Dicke in 1957 proposed a flat spacetime with a variable speed of light such that gravity works similar to a refractive index, slowing down the speed of light. ...
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2
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0
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59
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Any method to determine the gravitational constant $G$ from observations in cosmological scale?
By the observations in cosmological scale, I mean observations by astrophysicists like motions of quasars in far distance from us, relative motions of our galaxy to others, etc.
I know the famous ...
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