Space exploration, colonization
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Originally Posted By: mechtech2
BTW, the speed of light was almost certainly exceeded in the early Big Bang . Some galaxies are moving apart faster than the speed of light.
Not quite.
The speed of light applies to objects moving through space. The terms "expansion of the universe" and "Big Bang" describe the expansion of space itself. Some objects may move faster than light relative to each other, but they are not moving faster than light through space.
BTW, the speed of light was almost certainly exceeded in the early Big Bang . Some galaxies are moving apart faster than the speed of light.
Not quite.
The speed of light applies to objects moving through space. The terms "expansion of the universe" and "Big Bang" describe the expansion of space itself. Some objects may move faster than light relative to each other, but they are not moving faster than light through space.
Yes. For example, if you stand in a field, with the moon in one side of the sky, and spin around at a relatively normal rate.... Relative to you, the moon is moving faster than the speed of light. Also, if you take a laser that is capable of going extreme distances (thousands, and thousands of miles) and shake it back and forth from the wrist, the end of the laser is going faster than the speed of light.
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Originally Posted By: Tempest
Originally Posted By: Gary Allan
Yes. Give them iPods ..that will fix it.
How about synthetic oil?
I highly recommend a diet high in synthetic oil consumption for your continued good health ..and long life. It will benefit you, the nation, and the universe.
Originally Posted By: Gary Allan
Yes. Give them iPods ..that will fix it.
How about synthetic oil?
I highly recommend a diet high in synthetic oil consumption for your continued good health ..and long life. It will benefit you, the nation, and the universe.
Originally Posted By: Nick R
Yes. For example, if you stand in a field, with the moon in one side of the sky, and spin around at a relatively normal rate.... Relative to you, the moon is moving faster than the speed of light.
No, your orientation is simply changing.
Originally Posted By: Nick R
Also, if you take a laser that is capable of going extreme distances (thousands, and thousands of miles) and shake it back and forth from the wrist, the end of the laser is going faster than the speed of light.
The "end of the laser" isn't an object that is traveling. It's just whatever point is being illuminated by the laser.
Yes. For example, if you stand in a field, with the moon in one side of the sky, and spin around at a relatively normal rate.... Relative to you, the moon is moving faster than the speed of light.
No, your orientation is simply changing.
Originally Posted By: Nick R
Also, if you take a laser that is capable of going extreme distances (thousands, and thousands of miles) and shake it back and forth from the wrist, the end of the laser is going faster than the speed of light.
The "end of the laser" isn't an object that is traveling. It's just whatever point is being illuminated by the laser.
Originally Posted By: Nick R
Yes. For example, if you stand in a field, with the moon in one side of the sky, and spin around at a relatively normal rate.... Relative to you, the moon is moving faster than the speed of light.
Nope, YOU have to move faster than the speed of light in order to observe the moon moving faster than the speed of light. Think of releasing water from a filled sink down a rotating drain. What the rotating drain can observe is the water near the edge of the rotating surface rotates around itself at the same speed of its own rotation, not the water 5" away from itself suddenly travel side way faster than its own rotation (it hasn't reach the edge of the rotating drain yet).
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Also, if you take a laser that is capable of going extreme distances (thousands, and thousands of miles) and shake it back and forth from the wrist, the end of the laser is going faster than the speed of light.
Absolutely not. Have you try spraying your car with a garden hose while shaking it? Did the water that touches your car "travel" faster than the water speed coming out of the garden hose? The laser is just a glorified water stream coming out of a garden hose.
Yes. For example, if you stand in a field, with the moon in one side of the sky, and spin around at a relatively normal rate.... Relative to you, the moon is moving faster than the speed of light.
Nope, YOU have to move faster than the speed of light in order to observe the moon moving faster than the speed of light. Think of releasing water from a filled sink down a rotating drain. What the rotating drain can observe is the water near the edge of the rotating surface rotates around itself at the same speed of its own rotation, not the water 5" away from itself suddenly travel side way faster than its own rotation (it hasn't reach the edge of the rotating drain yet).
Quote:
Also, if you take a laser that is capable of going extreme distances (thousands, and thousands of miles) and shake it back and forth from the wrist, the end of the laser is going faster than the speed of light.
Absolutely not. Have you try spraying your car with a garden hose while shaking it? Did the water that touches your car "travel" faster than the water speed coming out of the garden hose? The laser is just a glorified water stream coming out of a garden hose.
Originally Posted By: crinkles
stuff space; we should figure out how to live on earth; that includes being less people on earth.
Any individual is free to reduce the population of the planet by their one, at any time.
stuff space; we should figure out how to live on earth; that includes being less people on earth.
Any individual is free to reduce the population of the planet by their one, at any time.
Originally Posted By: Tempest
Any individual is free to reduce the population of the planet by their one, at any time.
People have been doing that in the developed world (i.e. Japan, France, etc) by having fewer kids.
Any individual is free to reduce the population of the planet by their one, at any time.
People have been doing that in the developed world (i.e. Japan, France, etc) by having fewer kids.
Originally Posted By: eljefino
Therefore, an alien race that survived our atmosphere, temperature, etc would know about us before we knew about them. They'd find us first. We would do well to befriend them.
If there's anything I've learned from the movies it's that we always win.
Mars Attacks, Independence Day, War of the Worlds, Men in Black, Starship Troopers....
Okay, so maybe not in Invasion of the Body Snatchers. But Will Smith wasn't even born for the first one and was only 10 for the 2nd one.
Therefore, an alien race that survived our atmosphere, temperature, etc would know about us before we knew about them. They'd find us first. We would do well to befriend them.
If there's anything I've learned from the movies it's that we always win.
Mars Attacks, Independence Day, War of the Worlds, Men in Black, Starship Troopers....
Okay, so maybe not in Invasion of the Body Snatchers. But Will Smith wasn't even born for the first one and was only 10 for the 2nd one.
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Originally Posted By: Tempest
Originally Posted By: crinkles
stuff space; we should figure out how to live on earth; that includes being less people on earth.
Any individual is free to reduce the population of the planet by their one, at any time.
Nah. No need for that. Protecting someone's "interests" usually culls the herd every so often.
Originally Posted By: crinkles
stuff space; we should figure out how to live on earth; that includes being less people on earth.
Any individual is free to reduce the population of the planet by their one, at any time.
Nah. No need for that. Protecting someone's "interests" usually culls the herd every so often.
Originally Posted By: PandaBear
Originally Posted By: Nick R
Yes. For example, if you stand in a field, with the moon in one side of the sky, and spin around at a relatively normal rate.... Relative to you, the moon is moving faster than the speed of light.
Nope, YOU have to move faster than the speed of light in order to observe the moon moving faster than the speed of light. Think of releasing water from a filled sink down a rotating drain. What the rotating drain can observe is the water near the edge of the rotating surface rotates around itself at the same speed of its own rotation, not the water 5" away from itself suddenly travel side way faster than its own rotation (it hasn't reach the edge of the rotating drain yet).
Quote:
Also, if you take a laser that is capable of going extreme distances (thousands, and thousands of miles) and shake it back and forth from the wrist, the end of the laser is going faster than the speed of light.
Absolutely not. Have you try spraying your car with a garden hose while shaking it? Did the water that touches your car "travel" faster than the water speed coming out of the garden hose? The laser is just a glorified water stream coming out of a garden hose.
You are not thinking about this the right way. Nothing is physically moving faster than the speed of light- it simply appears to be doing so. I' m bad at explaining this kind of thing, so I will just copy from the wikipedia page.
FTL phenomena
In these examples, certain influences may appear to travel faster than light, but they do not convey energy or information faster than light, so they do not violate special relativity.
[edit]Daily motion of the Heavens
For an earthbound observer objects in the sky complete one revolution around the earth in 1 day. Proxima Centauri, which is the nearest star outside the Solar system, is about 4 light years away.[31] On a geostationary view Alpha Centauri has a speed many times greater than "c" as the rim speed of an object moving in a circle is a product of the radius and angular speed.[32] It is also possible on a geostatic view for objects such as comets to vary their speed from subluminal to superluminal and vice versa simply because the distance from the earth varies. Comets may have orbits which take them out to more than 1000 AU.[33] Circumference of a circle radius 1000 AU is greater than one light day. In other words, a comet at such a distance is superluminal in a geostatic frame.
[edit]Light spots and shadows
If a laser is swept across a distant object, the spot of light can easily be made to move at a speed greater than c.[34] Similarly, a shadow projected onto a distant object can be made to move faster than c.[35] In neither case does any information travel faster than light.
Another example is my moon example. If you spin around once per second, with the moon near the horizon, if you look at it from a relative point of view, relative to you the moon is completing a complete orbit in one second. The circumference of the moons orbit is roughly 1,480,000 miles. So it would appear that the moon, if you are spinning 1 time per second, would appear to be moving 1,480,000 per second- which is greater than the speed of light.
Again, no information or matter is being transmitted/moved FTL, this is purely abstract relative stuff.
Originally Posted By: Nick R
Yes. For example, if you stand in a field, with the moon in one side of the sky, and spin around at a relatively normal rate.... Relative to you, the moon is moving faster than the speed of light.
Nope, YOU have to move faster than the speed of light in order to observe the moon moving faster than the speed of light. Think of releasing water from a filled sink down a rotating drain. What the rotating drain can observe is the water near the edge of the rotating surface rotates around itself at the same speed of its own rotation, not the water 5" away from itself suddenly travel side way faster than its own rotation (it hasn't reach the edge of the rotating drain yet).
Quote:
Also, if you take a laser that is capable of going extreme distances (thousands, and thousands of miles) and shake it back and forth from the wrist, the end of the laser is going faster than the speed of light.
Absolutely not. Have you try spraying your car with a garden hose while shaking it? Did the water that touches your car "travel" faster than the water speed coming out of the garden hose? The laser is just a glorified water stream coming out of a garden hose.
You are not thinking about this the right way. Nothing is physically moving faster than the speed of light- it simply appears to be doing so. I' m bad at explaining this kind of thing, so I will just copy from the wikipedia page.
FTL phenomena
In these examples, certain influences may appear to travel faster than light, but they do not convey energy or information faster than light, so they do not violate special relativity.
[edit]Daily motion of the Heavens
For an earthbound observer objects in the sky complete one revolution around the earth in 1 day. Proxima Centauri, which is the nearest star outside the Solar system, is about 4 light years away.[31] On a geostationary view Alpha Centauri has a speed many times greater than "c" as the rim speed of an object moving in a circle is a product of the radius and angular speed.[32] It is also possible on a geostatic view for objects such as comets to vary their speed from subluminal to superluminal and vice versa simply because the distance from the earth varies. Comets may have orbits which take them out to more than 1000 AU.[33] Circumference of a circle radius 1000 AU is greater than one light day. In other words, a comet at such a distance is superluminal in a geostatic frame.
[edit]Light spots and shadows
If a laser is swept across a distant object, the spot of light can easily be made to move at a speed greater than c.[34] Similarly, a shadow projected onto a distant object can be made to move faster than c.[35] In neither case does any information travel faster than light.
Another example is my moon example. If you spin around once per second, with the moon near the horizon, if you look at it from a relative point of view, relative to you the moon is completing a complete orbit in one second. The circumference of the moons orbit is roughly 1,480,000 miles. So it would appear that the moon, if you are spinning 1 time per second, would appear to be moving 1,480,000 per second- which is greater than the speed of light.
Again, no information or matter is being transmitted/moved FTL, this is purely abstract relative stuff.
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Originally Posted By: Nick R
You are not thinking about this the right way. Nothing is physically moving faster than the speed of light- it simply appears to be doing so. I' m bad at explaining this kind of thing, so I will just copy from the wikipedia page.
I think I'm thinking this the right way, but the wikipedia page is not.
I think it is the "confusion" of angular velocity vs linear velocity. You are observing the angular velocity of a travel object when you spin. The moon orbiting 1/2 the current distance from you will appears to travel the same speed, but it is 1/2 of its original linear velocity (tangential to the orbit).
You mention that if you spin faster than the moon traveling as if it is traveling at the speed of light, you will be able to observe the moon travel faster than the speed of light. But in reality that's in psychology because you believe what your eyes tell you as if it is the same observation distance away.
What your eye see if the moon is traveling at 1/2 the speed of light (tangential to the orbit) when you rotate, is in reality the speed of (your psychological observed speed) * (your eye from your rotational axle) / (moon from your rotational axle), a huge discount from what you think you are seeing. You though you were observing the moon traveling at 1/2 the speed of light, but you really were only observing a few hundred thousands miles per hour.
So when you triple that and though you were observing 1.5x the speed of light, you are really only observing 3x (a few hundred thousands miles per hour) according to the example above, which is the tangential travel speed of your eyeball rotating along the axle.
Your speed is exactly as you observed, and none of the law of physics were violated.
You are not thinking about this the right way. Nothing is physically moving faster than the speed of light- it simply appears to be doing so. I' m bad at explaining this kind of thing, so I will just copy from the wikipedia page.
I think I'm thinking this the right way, but the wikipedia page is not.
I think it is the "confusion" of angular velocity vs linear velocity. You are observing the angular velocity of a travel object when you spin. The moon orbiting 1/2 the current distance from you will appears to travel the same speed, but it is 1/2 of its original linear velocity (tangential to the orbit).
You mention that if you spin faster than the moon traveling as if it is traveling at the speed of light, you will be able to observe the moon travel faster than the speed of light. But in reality that's in psychology because you believe what your eyes tell you as if it is the same observation distance away.
What your eye see if the moon is traveling at 1/2 the speed of light (tangential to the orbit) when you rotate, is in reality the speed of (your psychological observed speed) * (your eye from your rotational axle) / (moon from your rotational axle), a huge discount from what you think you are seeing. You though you were observing the moon traveling at 1/2 the speed of light, but you really were only observing a few hundred thousands miles per hour.
So when you triple that and though you were observing 1.5x the speed of light, you are really only observing 3x (a few hundred thousands miles per hour) according to the example above, which is the tangential travel speed of your eyeball rotating along the axle.
Your speed is exactly as you observed, and none of the law of physics were violated.
If you rotate your head, then objects at the periphery of the universe will appear to be rotating at multiple times the speed of light...but they aren't.
Look out the side window of your car while travelling at 60MPH.
Trees close to you are whizzing by at 60MPH, those a mile away are dawdling...all of them are stationary.
Look out the side window of your car while travelling at 60MPH.
Trees close to you are whizzing by at 60MPH, those a mile away are dawdling...all of them are stationary.
Originally Posted By: Shannow
Once asked an electrical engineer how fast electrons travelled in wire.
He explained that it was the speed of light.
Next question was why we don't need thrust blocks on turns.
Blank stare "I'm too busy"
the electrons travel near the speed of light but not quite. and, they don't have enough momentum to need thrust blocks because the cahnge in momentum (which is a vector - changes direction but not magnitude) is so small.
Once asked an electrical engineer how fast electrons travelled in wire.
He explained that it was the speed of light.
Next question was why we don't need thrust blocks on turns.
Blank stare "I'm too busy"
the electrons travel near the speed of light but not quite. and, they don't have enough momentum to need thrust blocks because the cahnge in momentum (which is a vector - changes direction but not magnitude) is so small.
Originally Posted By: Spazdog
If there's anything I've learned from the movies it's that we always win.
Mars Attacks, Independence Day, War of the Worlds, Men in Black, Starship Troopers....
What I've learned from movies is that all these disasters never happen in New Zealand.The end of the world may come,but we'll be sweet down here.
If there's anything I've learned from the movies it's that we always win.
Mars Attacks, Independence Day, War of the Worlds, Men in Black, Starship Troopers....
What I've learned from movies is that all these disasters never happen in New Zealand.The end of the world may come,but we'll be sweet down here.
Originally Posted By: Shannow
Once asked an electrical engineer how fast electrons travelled in wire.
He explained that it was the speed of light.
Next question was why we don't need thrust blocks on turns.
Blank stare "I'm too busy"
That is not true, electrons move much slower than the speed of light in a conductor (I am an EE as well). They move at what is called the "drift velocity"
Think of pushing on the end of a stick, the FORCE propagates through the stick at about the speed of light. The electric field (force) pushes each particle in a domino-like effect, but the stick itself and its particles do not move at the speed of light. Only the transmitted force does.
In an 18 gauge copper wire with 3A of current, the electrons move about 1 METER per hour. Very slow.
http://en.wikipedia.org/wiki/Drift_velocity
Once asked an electrical engineer how fast electrons travelled in wire.
He explained that it was the speed of light.
Next question was why we don't need thrust blocks on turns.
Blank stare "I'm too busy"
That is not true, electrons move much slower than the speed of light in a conductor (I am an EE as well). They move at what is called the "drift velocity"
Think of pushing on the end of a stick, the FORCE propagates through the stick at about the speed of light. The electric field (force) pushes each particle in a domino-like effect, but the stick itself and its particles do not move at the speed of light. Only the transmitted force does.
In an 18 gauge copper wire with 3A of current, the electrons move about 1 METER per hour. Very slow.
http://en.wikipedia.org/wiki/Drift_velocity
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The laser will exceed C by geometry only, the same as pointing your finger. No part is actually moving. New parts are being emitted/ displayed.
Discover Magazine had an article about the 'Streetlight Effect'.
The analogy was that only obvious things that are easily observable are considered. [like objects in a street lamp's light at night - outside of it is dim or non viewable]
It is the aberrant and events and anomalies which should be more strongly considered.
And there are all sorts of anomalies and rule breakers out in space. Things that don't fit . They are normally overlooked so someone can make generalizations.
Discover Magazine had an article about the 'Streetlight Effect'.
The analogy was that only obvious things that are easily observable are considered. [like objects in a street lamp's light at night - outside of it is dim or non viewable]
It is the aberrant and events and anomalies which should be more strongly considered.
And there are all sorts of anomalies and rule breakers out in space. Things that don't fit . They are normally overlooked so someone can make generalizations.
Originally Posted By: KilgoreBass
That is not true, electrons move much slower than the speed of light in a conductor (I am an EE as well). They move at what is called the "drift velocity"
Think of pushing on the end of a stick, the FORCE propagates through the stick at about the speed of light.
I likened it to a hose full of marbles.
Push a marble in, and another instantaneously pops out the other end, with nothing moving at the speed of light.
That is not true, electrons move much slower than the speed of light in a conductor (I am an EE as well). They move at what is called the "drift velocity"
Think of pushing on the end of a stick, the FORCE propagates through the stick at about the speed of light.
I likened it to a hose full of marbles.
Push a marble in, and another instantaneously pops out the other end, with nothing moving at the speed of light.
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