How do we argue that gravity is not a force due to curvature of space-time?

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Gravity is argued to be a result of the curvature of space-time rather than a traditional force, as massive objects like Earth follow geodesics created by this curvature. The Earth’s orbit around the sun exemplifies this concept, where it moves along a curved path due to the sun's influence on space-time, not because of a direct force acting on it. All objects, regardless of size, exert gravitational attraction, but this force is significantly weaker between smaller objects, making it negligible in everyday interactions. The discussion emphasizes the importance of understanding geodesics and the geometry of space-time, suggesting that gravity does not depend on the material composition of objects. For further exploration, references to experiments like Eotvos and Gravity Probe B are recommended to support the argument in the essay.
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Homework Statement


How do we argue that gravity is not a force due to curvature of space-time?


Homework Equations



I'm new.. I don't even understand the eqn of tensor calculus.

The Attempt at a Solution



No force is needed for as massive objects follows the curvature of spacetime with their innate velocity? Just like the Earth orbits around the sun because its velocity sustains it in the path of curvature caused by the sun?

I'm writing an essay on this. and I need more points to elaborate on curvature.
Thanks for all help given.
 
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Yea basically. The Earth thinks its going in a straight line, but since the space around Earth is curved by the sun, the Earth follows a circular trajectory as a result. The key word "geodesic."
 
What gives the Earth its inherent/innate velocity to maintain its trajectory/geodisic movement instead of being attracted towards the sun?
Does this velocity only apply to massive objects? what about smaller objects like humans, do we attract each other?
 
well the Earth is attracted towards the sun, or else it would fly out into space. It continues to move though because there is nothing to stop it (see, "Newtons first law of motion").
Yes, all objects attract all other things gravitationally, even humans. Even individual atoms attract others gravitationally, but the force is extraordinarily weak and it is really only noticeable in very large objects such as planets and stars.
 
A telling case could be made against gravity being interpreted as curvature of spacetime if there were a dependence of gravity on the material an object is made of instead of just it's mass. So a gold satellite would orbit differently from an aluminum satellite it would make it difficult to interpret as geometry. As far as we know so far, they don't. Look up the Eotvos experiment. Work in this direction is still going on. Look up Gravity Probe B. Work those into your essay.
 
One point to note... My essay is to understandable to a layman and my tutor told me to focus more on the geometry/geodesic such that NO FORCE is required between masses.

I was wondering how do I explain geodesics in a laymanized manner. sigh
 
(a) The polarisation pattern is elliptical with maximum (1,1) and minimum (-1,-1), and anticlockwise in direction. (b) I know the solution is a quarter-wave plate oriented π/4, and half-wave plate at π/16, but don't understand how to reach there. I've obtained the polarisation vector (cos π/8, isin π/8) so far. I can't find much online guidance or textbook material working through this topic, so I'd appreciate any help I can get. Also, if anyone could let me know where I can get more...

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