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Oke, so my mind is blown by Einsteins view on gravity, at least as far as I understand the basics and principles he based his views on.

One of the first things that struck me was that most of his equations were based on the fact the photons had no mass, something which is virtually impossible to verify experimentally and something I can not convince myself of.

Now he states that mass bends spacetime: in other words, objects can only move in straight paths, but because the "surface" of a path can be bent, the trajectory relative to the mass is bent. So as a reaction, I did the following thought experiment that would separate Newton from Einstein:

Image in space (completely empty) and two objects with mass M and m (whatever the values) placed from a distance R apart completely at rest. According to my interpretation of Einstein, nothing will happen because even if spacetime is bent they have no motion themselves. Our earth orbits the sun because it initially had a motion and is now travelling in an infinite straight line, which becomes an ellipse due to curvature. Newtons would of course state that in my thought experiment, the two masses would collide.

After I realized this, I started to question Einstein's view. Is my basic interpretation correct about Einstein, and how would you (expert/physics professor/lover) respond to this thought? I personally find it pretty confronting...

BTW I'm just a high school student, potentially going to Cambridge to study physical sciences...

user209347
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Your claim that nothing will happen because they initially have no velocity is where things start to go wrong. In fact everything in relativity has the same speed (the speed of light). A particle that looks to be "at rest" in some reference frame simply has all of its velocity pointing in the "time direction".

This is an intuitive reason why you would see time passing more slowly on a spaceship moving with high (spacial) velocity relative to you. More of their speed is in a "space direction" so less has to be in the "time direction" in order to make the overall speed c.

When space is curved by some mass in general it won't be the case that a worldline with all of its speed in the time direction is a valid "straight line" called a geodesic. Paths which are allowed have to obey the geodesic equation. In particular the spacetime around a spherically symmetric mass is what is called the Schwarzschild metric and a stationary (in space) worldline definitely isn't a solution to the geodesic equation with that metric.

or1426
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