posted
I think what is being asked is along these lines: if light isn't slowed down by gravity, then what happens to light that is flying straight up?
Well, consider a rocket on Earth. To leave the planet, that rocket has to accelerate to about 25,000 miles per hour.
But imagine the Earth was much denser and larger than it is. Or, conversely, imagine the rocket is much less powerful.
Gravity, at the surface, is pulling down at 32 feet per second squared. If you want to jump into the air, or move anything at all in that direction, you need to apply an acceleration greater than 32 f/s/s to it. So take our weak rocket. It's thrust is exactly 32 f/s/s. So what happens to the rocket? Nothing. That is, for as long as it is firing, it will not fall. But it cannot go anywhere. It is not, from the point of view of the surface of the earth, going anywhere. But it does have a speed.
In the same way, a black hole, at the event horizon, has an escape velocity of exactly lightspeed. A photon, released right at this boundary, aimed straight up, will still be traveling at c. But all this does is counter the gravitational pull of the hole. The photon can't get away from it. That's why it's a black hole. Beneath the event horizon, the gravitational pull is even greater, and light, along with everything else, spirals down into the singularity.
Registered: Mar 1999
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Cartman
just made by the Presbyterian Church
Member # 256
posted
Adding to the confusion, photons aren't factually influenced by gravity. They merely follow the shortest possible route through the fabric of spacetime - in other words, a straight line. This is counter-intuitive because the mind has great difficulty visualising more than three spacial dimensions. All black holes really do is distort the continuum so severely that the direction in which light travels gets warped beyond all recognition.
Basically, something woul alter the rocket/light ray's speed or trajectory, even if it's only by the tinniest fraction of a miniscule percent. But that is all that is needed for the stalemate to be broken.
-------------------- Yes, you're despicable, and... and picable... and... and you're definitely, definitely despicable. How a person can get so despicable in one lifetime is beyond me. It isn't as though I haven't met a lot of people. Goodness knows it isn't that. It isn't just that... it isn't... it's... it's despicable.
Registered: Mar 1999
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posted
Whether the hypothetical situation is possible or not isn't what's important, though. We're just talking about how the photon behaves.
Registered: Mar 1999
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posted
Obviously, my joke didn't go over as intended. That's what I get for making a reference to something about five people understand...
Registered: Mar 1999
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Cartman
just made by the Presbyterian Church
Member # 256
posted
Six.
(yet another obscure reference)
Registered: Nov 1999
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posted
I thought you were going for some sort of "A butterfly flaps its wings in Australia and causes a thunderstorm in Miami" sort of thing.
-------------------- Yes, you're despicable, and... and picable... and... and you're definitely, definitely despicable. How a person can get so despicable in one lifetime is beyond me. It isn't as though I haven't met a lot of people. Goodness knows it isn't that. It isn't just that... it isn't... it's... it's despicable.
Registered: Mar 1999
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posted
I was. But, more specifically, I was going for the Daryus == Jeff Goldblum == Dr. Ian Malcolm == explaining chaos theory in Jurassic Park.
Registered: Mar 1999
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So, if light slows enough, then it won't be long beofre we can break that barrier... or start moving slower ourselves...
-------------------- "You are a terrible human, Ritten." Magnus "Urgh, you are a sick sick person..." Austin Powers A leek too, pretty much a negi.....
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