All Questions
15
questions
4
votes
6
answers
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How does general relativity theory explain gravitational pull? [duplicate]
I watched some videos on YouTube that explain why gravity is not a force,
according to general relativity theory.
I can wrap my head around the idea that spacetime can be curved due to a massive mass,
...
- 141
1
vote
3
answers
108
views
Where is the normal force that pushes us up comes from if gravity is not a force according to general relativity?
https://youtu.be/XRr1kaXKBsU?t=530
I was watching this video and at this point he said that since gravity is not a force as per GR, we are left with only these normal forces pushing you up that ...
- 21
0
votes
2
answers
430
views
Why is gravity not a force? [duplicate]
Gravitation is the mutual attraction of masses, yet Einstein showed it is how spacetime is curved by mass and how mass moves in relation to this curvature. Why then do we still consider gravitation a &...
- 510
-1
votes
1
answer
83
views
Direction of spacetime curvature?
I am honestly new to all. But, I am confused about space time curvature and gravity.
I see in lots of graphs that the spacetime bends when there is a mass in it, and that bend is in the direction of ...
0
votes
0
answers
63
views
If there are no gravity under the general theory of relativity, how can we be attracted to massive objects (from the side)?
Watching this video, it is explained that there are no force of gravity under the general theory of relativity, but a force made by objects moving through spacetime.
The example made in this video to ...
- 131
4
votes
5
answers
1k
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If gravity isn’t a force how does it cause motion? [duplicate]
In general relativity, gravity is the effect of curving space-time caused by mass and is described as an acceleration.
So what exactly is causing this pull towards the earth?
Is a force not required ...
- 340
1
vote
2
answers
202
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How do you derive Newtonian Sum of Forces equation from GR?
This is what I have so far.
We start with the definition that force is the change in momentum with respect to time:$$\Sigma F_i =\frac{dP}{d\tau}$$Where $\Sigma F_i$ is the sum of forces, both applied ...
- 584
3
votes
1
answer
202
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What is the sum of forces equation in curved spacetime?
I've been thinking about the Sum of Forces equation and the fact that gravity isn't really a force. So what is the proper way to think about this equation when dealing with objects in a gravitational ...
- 584
1
vote
3
answers
280
views
Why is gravity generally defined as the consequence of a curve rather than a pull? [closed]
This question is asking to better understand the semantics of mainstream physics. My assumption being there is a specific narrative behind the preferred term. In any case, it seems like an essential ...
- 261
7
votes
2
answers
1k
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Can we describe all forces as a curvature in space-time?
If we have Einstein's field equation
$$R_{\mu\nu} - \frac{1}{2}g_{\mu\nu}R=kT_{\mu\nu}$$
could we generalize it to
$$R_{\mu\nu} - \frac{1}{2}m_{\mu\nu}R=kS_{\mu\nu}$$
where $S_{\mu\nu}$ is the source ...
- 775
3
votes
3
answers
2k
views
Do all four fundamental forces have effects on spacetime?
Since gravity, a fundamental force, takes effect through ripples in spacetime, do the other fundamental forces do the same?
For example, since gravitational waves are ripples in space time, are ...
- 41
2
votes
1
answer
1k
views
Gravity: Why Do things fall to Earth? [duplicate]
If gravity is in reality spacetime geometry why when I drop an object on the surface of the Earth does it fall to the ground? Does spacetime push it?
- 203
5
votes
2
answers
1k
views
Can other fundamental forces bend spacetime?
I was wondering what makes gravity so special that it bends spacetime? and if it is part of the four-fundamental forces, why or why cant the other forces bend the time space continuum?
- 757
18
votes
4
answers
5k
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ALL "forces" as manifestations of properties of space-time
I apologize if this seems like a quack question, but I need some insights by those who know much more than me in Physics.
Anyway, the gravitational "force" (not really a force) is a manifestation of ...
- 750
81
votes
17
answers
59k
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How exactly does curved space-time describe the force of gravity?
I understand that people explain (in layman's terms at least) that the presence of mass "warps" space-time geometry, and this causes gravity. I have also of course heard the analogy of a blanket or ...
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