Tagged Questions
2
votes
2answers
104 views
Is Earth's orbit around the sun affected by the ~8 minutes light delay?
Gravitational change occurs at the speed of light. As a consequence, we experience on Earth the gravitational attraction of the sun based on its position relative to us ~8 minutes ago. How does this ...
1
vote
5answers
137 views
How universal gravitation falls short
As a non physicist I can understand how Newtonian mechanics falls short in cases of high velocity etc. and is properly generalized by the special theory of relativity.
What is not clear to me is how ...
3
votes
2answers
140 views
Theoretical need for Newtonian Gravity
I've been wondering:
Are there, still, some advantages, for current research, to study Newtonian gravity? I mean, not experimentally, where Newton gravity is a very good approximation to everyday ...
2
votes
5answers
239 views
Einstein gravity versus Newton's gravity
What's the basic difference between the gravity as seen by Einstein, and that by Newton?
1
vote
3answers
244 views
Similarity between the Coulomb force and Newton's gravitational force
Coulomb force and gravitational force has the same governing equation. So they should be same in nature. A moving electric charge creates magnetic field, so a moving mass should create some force ...
0
votes
2answers
456 views
Newtonian gravity vs. general relativity: exactly how wrong is Newton?
Is there a simple function I can use to describe the difference between simple Newtonian dynamics and the actual observed motion? Or maybe some ratios for common examples of, say, the motion of stars ...
1
vote
1answer
224 views
Einstein's Explanation for gravity vs. Newtonian
I was trying to understand the Einstein's explanation for gravity (gravitational force), and while I am able to understand why two moving masses will be attracted, due to the curving of the space, I ...
0
votes
0answers
68 views
Trajectory of a photon due to a constant/uniform gravitational force [closed]
I have a small problem of physics linked to a basic ray tracing algorithm. My problem is the following :
At $t = 0$, a photon at the position $(x_0 = x_\text{min},y_0 = y_\text{min})$ with the ...
1
vote
1answer
296 views
How does Newton's 2nd law correspond to GR in the weak field limit?
I can only perform the demonstration from the much simpler $E = mc^2$.
Take as given the Einstein field equation:
$G_{\mu\nu} = 8 \pi \, T_{\mu\nu}$
... can it be proved that Newton's formulation ...
2
votes
1answer
143 views
Trying to understand the weak gravitational field metric (2)
I'm still struggling with Carroll's discussion of the Newtonian Limit. I'm hoping no one will mind if I ask several questions here as they all relate to the same section (pages 105-106) of his ...
5
votes
1answer
237 views
Trying to understand the weak gravitational field metric (1)
In Carroll's online Lecture Notes on General Relativity (p112) he says, "the weakness of the gravitational field allows us to decompose the metric into the Minkowski form plus a small perturbation"
...
8
votes
6answers
1k views
Is Newton's Law of Gravity consistent with General Relativity?
By 'Newton's Law of Gravity', I am referring to
The magnitude of the force of gravity is proportional to the product of the mass of the two objects and inversely proportional to their distance ...
