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time slows in the presence of strong gravitational fields It's not the gravitational field that determines time dilation, it's the gravitational potential. The Newtonian approximation really isn't correct here, but let's use it anyway for insight: The potential falls off like $1/r$ with distance $r$. The field falls off like $1/r^2$. Tidal effects go like ...


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It's explained on the wikimedia page for the image: The various gravity assists form visible peaks on the left, while the periodic variation on the right is caused by the spacecraft's orbit around Saturn. Since Saturn is moving relative to the Sun, when Cassini is at a point in its orbit that causes it to move in the same direction relative to ...


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The gravity from the black hole (BH) will have no effect on their ability to take off from the water planet itself. Objects in orbit feel weightless (think astronauts in the ISS). If you're only worried about getting off the water planet then there should be no problem. However, if they were to try to put some distance between themselves and the BH then ...


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1.When they travel to the watery planet, they say that 1 hour on this planet is 7 yrs om earth. How is this possible? Is the planet moving at a speed close to c? Or does strong gravitational field influence time? Sure. This is gravitational time dilation. It's due to the gravitational field of the black hole. You can calculate it using $$\frac{d ...


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The simplest reason for this is the fact that gravitational time dilation is governed, to leading order (in the zero-spin case for simplicity), by the factor $\sqrt{1 -\frac{2GM}{c^{2}r}}$. Now, just to make our measurements easier, let's rewrite the mass in terms of the radius of the event horizon: $$r_{0} = \frac{2GM}{c^{2}}$$ Now, our time dilation ...


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Generally true because during the acceleration phase fuel that will later be burned is accelerated along with the ship, whereas upon deceleration the overall mass of the ship will be smaller, requiring less fuel to slow it.


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The answer to this question depends on your assumption about the continuity of the "metric", the descriptor of the gravitational field. Case 1: Assume that the metric can be discontinuous. In this case the gravitational potential increases abruptly as one crosses the wormhole's throat. It seems that an object entering the lower mouth (A) and immediately ...


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I think this answer is very hard to answer exactly, since it is not so easy to perform the necessary calculations in the framework of general relativity. It is quite easy to start with curved spacetime that represents a traversable wormhole and investigate, how the matter must be distributed to cause the curvature and investigate what by what forces does it ...


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Disclaimer: I'm not a GR expert, but this is how this question has been explained to me by other physicists before. If I got something wrong, please correct me. The traveler does indeed not have to exert as much work to leave the gravity well via the wormhole compared to the normal route. They are not repelled from mouth A nor attracted to mouth B by any ...


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This question is very similar to mine, but does not consider gravitational wells aside from the wormhole itself. Actually I think that question does consider a gravitational well that exists in the surrounding space. What seems to me to be different about your question is that you're asking about the forces exerted on objects as they move around ...



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