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As I sit here writing this, I would appear to be motionless. In actuality, I am moving at a speed that would impress even the most dangerous of thrill seakers. Don't fret Sean White, we're in this together. As our home spins on its axis it carries us along with it. And as our home makes it annual journey around our star, our speed increases. As our star travels in the soft spiral arms around the center of our galaxy, our apparently motionless lazy day actions are all most completely shattered! As the immense power of the big bang carries us still faster still. We can now see that even while traveling faster than the speed of sound, we are traveling much faster.
Not to mention the effects dark matter may have on our motion. My first question is, how fast are we moving? Secondly, what would happen to time if I completely stopped and let all of that wiz by me? Last, but most definitely not least is, since the only two things that I can tell are constant are time and movment. Are they one in the same? Is what we experience as time only a side effect to our movment? |
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Hey there!
Relative to what? Linear motion is relative. It can only be measured relative to something. Rotation on the other hand, is absolute. There are ways you can tell whether you are rotating or not without having to compare your motion, position, or orientation to anything. Not so with linear motion. Complicating that is the fact that linear motion is part of all rotation. For example, Earth rotates once per sidereal day (23 hours, 56 minutes), so a point on the equator has a linear velocity of 465 m/s to the east, relative to an imaginary point at Earth's center. Earth revolves around the Sun once per sidereal year (365.2564 days), so it has a linear speed of about 30 km/s relative to a point at the center of the Sun. The Sun and Solar System revolve around the center of the Milky Way roughly once per 230 million years, so it has a linear speed of roughly 300 km/s relative to a point at the center of the galaxy. What is interesting is that on the largest scale at which we are able to measure our own speed, there is something available for us to measure against. That is the cosmic background radiation (CBR). We don't actually measure our speed relative to the light itself, but in effect we measure our speed and direction of motion relative to the matter which emitted the light 13.7 billion years ago, by comparing the amount of redshift of the CBR in different directions. It shows that the center of the Milky Way galaxy is moving at roughly 600 km/s. (I tried to find the direction it is in but didn't get a clear answer. It looks like it might be a bit southeast of the constellation Leo.) This speed and direction is determined by measuring the redshift of the CBR at Earth, then removing the redshift due to the motions of the Earth described above. The measurements show that the Earth itself has a net motion relative to the matter which emitted the CBR of roughly 400 km/s in the direction of the constellation Leo. (11 hours R.A., 6 degrees north latitude) Quote:
If you slowed down your speed of motion in orbit around the center of the galaxy, and maintained your position using rockets to prevent you from falling toward the center, your clocks would appear to slow very slightly as viewed by those whizzing past you. Quote:
measured by movement, but I would not say that time is movement, nor that time is a side effect of movement. Time is what you measure with clocks, but time evidently passes whether there is any kind of clock (manmade or naturally-existing) to measure it or not. Time is part of the measurement of all change, and all change appears to involve motion. So you are right at least to the extent that motion is intimately involved with time, and our perception of time. -- Jeff, in Minneapolis
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http://www.FreeMars.org/jeff/ "The other planets? Well, they just happen to be there, but the point of rockets is to explore them!" -- Kai Yeves |
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I would think that, as we are always moving that this may have something to do with how we experience time. I also thought that the faster you go, the slower my clock would tick compared to someone moving slower than I? My thought would be, if i could completely stop and stay in the same spot which i currently am in the universe, zero movement, that my clocks would speed up out of control? No? Why would my clock slow as I slowed down?
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faster they are moving relative to each other, the slower the other person's clock appears to be ticking. If one person with a clock is accelerating in a circle at constant speed near another person with a clock, who is not accelerating, the clock going in a circle will appear to be ticking slow to the other person, and that other person's clock will appear to be going fast to the person who is accelerating. Quote:
Every measurement of position and speed is relative to something else. You can measure the speed of two bodies relative to each other, but neither body is moving faster than the other. -- Jeff, in Minneapolis
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http://www.FreeMars.org/jeff/ "The other planets? Well, they just happen to be there, but the point of rockets is to explore them!" -- Kai Yeves |
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By having an acceleration due to gravity even though the speed of orbit stays the same brings in frame dragging through space and over a suitable interval can be measured as a difference in recorded time between the person holding one clock on the planet and the other person holding a second clock on the orbiting vehicle. When it is done with planes the gravity is still present but the lift of the wings replaces the need to maintain a velocity in orbit and can be replaced by the velocity of the aeroplane but it is the action of gravity or if you like the acceleration toward the planet which causes frame dragging that makes the difference.
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"Nature is obliged to let reality determine its laws, whereas mathematics is under no such constraint." |
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If a circumstance were imagined where two clocks traveling through space at two different speeds showed the same time on them, and then one accelerated to reach the exact speed of the other ending up traveling parallel in close enough proximity, then they would show a time difference due to the period of acceleration of the one clock but the time difference would remain constant once they were traveling in sync? |
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center of that circle. I was referring to motion in a circle at constant speed relative to the center of the circle. The acceleration could be provided by the gravity of a planet, or by firing your rocket engines directly away from the center of the circle you want to make. Either way, your speed remains constant. -- Jeff, in Minneapolis
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http://www.FreeMars.org/jeff/ "The other planets? Well, they just happen to be there, but the point of rockets is to explore them!" -- Kai Yeves |
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__________________
"Nature is obliged to let reality determine its laws, whereas mathematics is under no such constraint." |
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A similar effect could be achieved by using a suitably long ladder.
__________________
"Nature is obliged to let reality determine its laws, whereas mathematics is under no such constraint." |
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Simsthefat: My first question is, how fast are we moving? Secondly, what would happen to time if I completely stopped and let all of that wiz by me?
Last, but most definitely not least is, since the only two things that I can tell are constant are time and movment. Are they one in the same? Is what we experience as time only a side effect to our movment? dcl: The speeds of the earth around the sun and around the center of the Milky Way galaxy are about 22 and 30 mi/sec., respectively. Nothing would happen to your perception of time. Time and movement are not the same. Movement does not affect our perception of passage of time as meassured in our own frame of reference, but it appears to us that time passes more slowly in a frame of reference that is moving with respect to us. Time also appears to us at points in a gravitational field stronger than that in our own location. |