If You Follow The Straightest Possible Path Through A Spacetime Diagram

1 you look at the bright star vega that is 25 light years away. So the diagram curves.

General Relativity Presentation Ragesh Asmitha M D T

B the mysterious force that we call gravity holds earth in orbit.

If you follow the straightest possible path through a spacetime diagram. Circles that were evenly spaced in flat spacetime become more widely spaced near the central mass. A earth is following the straightest path possible but spacetime is curved in such a way that this path goes around the sun. You will be weightless.

Follow me back to the roof. If we turn off gravity i just floattracing a straight line in this diagram. You are in free fallyou do not feel any weight or acceleration in a saddle shaped geometry what do the angles in a triangle add up to.

Any time you are traveling through space at constant speed any time your worldline is perfectly straight any time your worldline is following the straightest possible path through spacetime any time you are very far from any planet you can never be truly weightless. Earth is following the straightest path possible through spacetime but this path happens to go around and around the sun. They are following the straightest possible paths through space time but those paths happen to meet.

If your wordline is following the straightest possible path through spacetime then. Time runs more slowly at lower altitudes in a gravitational field. You must be traveling at the speed of light you get from one place to another as fast as possible you are in free fall you do not feel any weight or acceleration.

Suppose the room in which you are sitting was magically transported off the earth and sent accelerating through the universe at 98 ms2. Spacetime becomes highly curved around a large mass compressed into a tiny space. How does gravity affect time.

Gravity arises from curvature of spacetime. C earth and the sun are connected by a ropelike set of invisible subatomic particles. You must be accelerating.

What is a black hole. If you follow the straightest possible path through a spacetime diagram. What is a spacetime diagram what is a worldline what.

Around a black hole spacetime becomes so curved that nothing can escape. The mass of the sun causes spacetime to curve so freely moving objects such as planets and comets follow the straightest possible paths allowed by the curvature of spacetime. A freefalling object then follows the straightest possible path in spacetime.

Now a straight line takes me from the roof to the ground. None of the above.

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