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Old 06-August-2007, 02:44 PM
Peauxboy Peauxboy is offline
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Default Personal Speed in contrast to Light

Here is a table of speeds in km/h as I understand it...
Earth Rotation 1,670
Rotation around Sun 107,280
Solar System Rotation through Milky Way 700,000

Does this mean that I am moving in contrast to the speed of light at 808,950 km/h? Of course this assumes that everything is pointing in the same direction at the same time. Does that then mean that I am traveling at 1/1,334 the speed of light? Is my sense of time directly related to this ratio? Now I understand that for these figure to add up like this everything needs to be moving in the right direction at the same time which segues to the rest of my question. Does our relativistic view of time constantly change as our position against everything else is constantly changing?
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Old 06-August-2007, 04:12 PM
grant hutchison grant hutchison is offline
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You'll find that if you measure the speed of light, you'll always get the same value of 3x108 m.s-1. It doesn't matter what your state of motion relative to some other object, the speed of light is always the same for you. And likewise for anyone moving along with those other objects: they will also measure the speed of light, relative to their laboratory, as 3x108 m.s-1.
This can be demonstrated experimentally by, for instance, measuring the speed of light in the same laboratory at six-month intervals, so that the direction of motion of the Earth in its orbit around the sun has reversed during the intervening time. There's no difference in the measured speed of light.

The counterintuitive constancy of the speed of light is one of the observations on which the theory of relativity is founded.

Grant Hutchison
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Old 06-August-2007, 04:15 PM
Tucson_Tim Tucson_Tim is offline
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An example of Relativity:

A large spaceship takes off from Earth and obtains a velocity of 0.9c relative to Earth. A second smaller spaceship (that was stored on board) then takes off from the first spaceship and obtains a velocity of 0.9c relative to the first spaceship and in the same direction. Then an even smaller third spaceship that was stored on board the second spaceship takes off and obtains a velocity of 0.9c relative to the second spaceship and in the same direction. The third spaceship would still measure a passing light beam as c. Also, the third spaceship will still be measured as traveling less than c relative to the Earth. The measured speed of the third spaceship, relative to the Earth, is easily calculated using the Lorentz equations.
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Old 06-August-2007, 08:23 PM
Peauxboy Peauxboy is offline
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I guess I didn't state my question that well. The point I am making is that because I am part of all these moving bodies (planet, solar system, galaxy) my speed is in constant flux. Since my personal view of time is directly related to the closer I am to the speed of light, does that mean that my personal time is constantly fluctuating? I guess the mor eI think about it the more I realize my actual question is whether a body can be at a zero speed? To truly not move in any direction of the 3 dimensions.

Quote:
Originally Posted by grant hutchison View Post
You'll find that if you measure the speed of light, you'll always get the same value of 3x108 m.s-1. It doesn't matter what your state of motion relative to some other object, the speed of light is always the same for you. And likewise for anyone moving along with those other objects: they will also measure the speed of light, relative to their laboratory, as 3x108 m.s-1.
This can be demonstrated experimentally by, for instance, measuring the speed of light in the same laboratory at six-month intervals, so that the direction of motion of the Earth in its orbit around the sun has reversed during the intervening time. There's no difference in the measured speed of light.

The counterintuitive constancy of the speed of light is one of the observations on which the theory of relativity is founded.

Grant Hutchison
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Old 06-August-2007, 08:30 PM
grant hutchison grant hutchison is offline
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Quote:
Originally Posted by Peauxboy View Post
I guess I didn't state my question that well. The point I am making is that because I am part of all these moving bodies (planet, solar system, galaxy) my speed is in constant flux. Since my personal view of time is directly related to the closer I am to the speed of light, does that mean that my personal time is constantly fluctuating?
No, because you are never any closer to the speed of light.
Your view of other people's time is influenced by how close to the speed of light they appear to be moving relative to you. Your own personal time keeps on ticking at one second per second, and your own view of the speed of light is that it is always the same.

Grant Hutchison
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