First, your parenthetical has it backwards. Special relativity is a subset of general relativity. Specifically, special relativity ignores the effect of gravity.
I'm afraid that acceleration isn't the magic bullet that breaks through the paradoxes of relativistic velocities, though intuitively it seems to. Acceleration changes velocity, yes, but the same acceleration that raises my velocity with respect to one object decreases it with respect to another. To use your example of the space shuttle, it is better to consider the shuttle in relationship to the space station. When it is ready to leave the station and return to earth, it points away from the station and accelerates, increasing its velocity relative to the station, and experiencing all the effects of acceleration. Except that, the whole manuver is vectored specifically to decrease its orbital velocity, dropping it out of orbit.
So which is it? Does acceleration increase or decrease velocity? Earthly intuition tells me that the answer is obvious: if I'm hitting the accelerator, I'm increasing my velocity; if I'm hitting the brakes, I'm decreasing velocity.
But earthly intuition learned at the bottom of a massive gravity well isn't much help in understanding relativistic velocities. In a universe filled with an infinite number of objects, any acceleration changes my vector with all of those objects, increasing my velocity relative to some and decreasing it relative to others.
What the special theory of reletivity describes is not what objectively happens to me as I accelerate, but how two objects manifest themselves to each other at different shared velocities, regardless of which one is assumed to have "accelerated" (because what from one perspective may seem obviously to be acceleration may seem just as obviously to be deceleration from another perspective).
Intuition is a powerful prison. Given two objects in space converging at a shared velocity of.9 c, one a planet sized object and the other a subatomic particle, I will invariably assume that the massive object is at rest (or nearly at rest) and the subatomic particle is in a "high energy" state. Particularly if I am familiar with the special theory of relativity, I will "know" that it would be impossible to accelerate the planet to.9 c. So, it must be the subatomic particle that has been accelerated.
Except that, to the special theory, it doesn't matter how velocity is achieved. An observation made from either object would show an object approaching at.9 c, and the relativistic changes in mass, time, length, whatever, would be perceived accordingly. Which means, of course, that the observation of the planet by the particle would indicate an incredible energy state.
But then, isn't that the problem with cosmic rays? Given their velocity at even such a miniscule mass, their energy state is too high to be credible. So, relativistically speaking, cosmic rays are just as problematic as space ships or even planets traveling at near light speed.
Except that the special theory of relativity doesn't really directly address the acceleration of objects. What it addresses is the observation of objects that share a high velocity. Indirectly, it may tell you that, if you boost an object with a quantity of energy that would seem sufficient to take it over light speed, you will nonetheless measure its velocity as being less that c. Yet, the boost energy is still there, not lost to friction. Your object will hit with a force out of proportion to its measured speed, which we take to mean that it must be more massive than it was before you accelerated it.
But the special theory doesn't care what gets accelerated. For all the special theory cares, two objects blinking into existence with a shared velocity of.9 c isn't a problem. The special theory will predict how they will observe each other and what their impact on each other would be, but it doesn't really care how their relative velocity comes about, or which one is "really" in motion.
Whenever I run across a discussion of light speed or near-light speed travel, I always find myself asking, relative to what? Are people assuming that an object can be "at rest" with respect to the universe, such that it can then accelerate to a near-light speed? That would seem to be the tacit assumption of such discussions, because the only other alternative is that "velocity" is a vector relationship between any two objects. If that is the case, then any one object is at any given moment "traveling" at any number of velocities, depending on how many other objects in the universe you "relate" it to. And while our everyday experience tells us that mostly we are at rest - or close to it - with respect to our immediate surroundings, on the cosmic scale, and given the range of particles moving through this universe, it would seem pretty obvious that some of our exisiting velocities are already pretty close to light speed, even if those relationships are pretty far removed from us. To assume we are "at rest" and those other objects are "high energy" is pretty self-centered, which is intuitive and generally works for us, but doesn't really have a basis in science.
Einstein rules, and FTL space travel has about zero chance of ever existing.
If you pay attention to what Einstein actually said in the Special Theory of Relativity, much of the "rules" have more to do with what an observer sees than with what actually happens with the object being observed.
This is no small thing. Imagine for a moment that a particle accelerator on earth has fired a subatomic particle into space at an observed velocity of 99.999% of the speed of light. Of course, we would only consider the acceleration of a subatomic particle to such speeds because Einstein's theory tells us that, since mass increases with velocity, only the most infinitesmal particle can be so accelerated without impossible expenditures of energy.
Except.
From the perspective of that subatomic particle whizzing off into space, the earth is observed as having the same velocity. In fact, velocity is properly always a relationship between two objects, not a property possessed by one object (and then "objectively" observed by another).
And if the earth is observed as traveling at 99.999% of the speed of light, then it, too, must have gone through a similar increase in mass.
The fact is, some of Einstein's rules have to do mainly with observation - with our ability to perceive - and particularly with the limits of using light as a means of perceiving objects that we are in a relationship of motion with.
The way various posts have dealt with time dilation and the Doppler effect as separate issues in relativistic theory shows how people have gotten comfortable with Einstein's theories, rather than do what Einstein did and keep pushing at the gaps in the theories that were current in his day.
In doing some reading on Einstein's General Theory, I ran across the idea that Einstein's theory of how time dilates in the presence of an intense gravitational field could be proven by a red-shift in light affected by that gravitational field, the light functioning as a "clock" that would shift its spectrum in direct relationship with the gravitational time distortion.
Fine, I thought. Light does make a pretty reliable and observable clock. So, what does that mean for the Special Theory? Well, for objects moving away from each other, no problem. At relativistic velocities, there would be a red shift, which would fit with Einstein's theory of time dilation. However, since the Special Theory suggests dilation as the only relativistic time distortion caused by high velocity, any blue shift experienced by converging objects is really problematic. Blue-shifted light would indicate a contraction of time, something that the Special Theory doesn't consider at all. But maybe we should.
Do a few thought problems, and it becomes clear that, at least with regard to velocity, time dilation is but one side of a two-sided Doppler coin.
The Special Theory is great, but maybe not the last word, even in dealing with just velocity effects. It doesn't pay much attention to vectors. It hints at but doesn't really address the possibility that, when two objects have a relationship of extreme velocity, what is most distorted by relativistic effects is not either object's length, mass, or passage through time, but each object's ability to use light to "observe" the other, particularly with regard to its location and velocity.
After one hundred years of digesting the Special Theory, we really ought to be doing more than creating more dazzling illustrations of it. It needs correcting and refining, too.
I think it is interesting that, though the U.S. frequently is equated with unbridled free markets, there is the persistent residue of a different economic model that can still be found in lots of small towns and a few tight-knit urban neighborhoods. I don't have a label for it, but I've seen it at work. The small town/neighborhood model can be really determined about discouraging competition. Small town culture can find lots of ways to undercut the opening of a business that would undercut an existing business. Likewise, small town culture often puts a lot of pressure on locals to put up with being gouged by a local business, even though there is a better deal available, a few miles away. Yes, there is a price to pay for such parochialism, but likewise for globalism.
You're not that far off of describing the search engine I'd really like to see, sort of a "Name that Tune" search engine. Instead of inputting a text string, you would be able to put in a musical notation string and have the search engine return a listing of tunes that contain (or begin with, or end with, or repeat) that string. It would be useful for trying to deal (probably unsuccessfully) with those snippets of music that occasionally create an endless loop in your head. It would also help tunesmiths avoid inadvertent plagarism. You could put in the "new" tune you just composed and be reminded that it was actually an old tune you heard once at a party ten years ago.
The most dependable printer I've ever had is a Stylewriter 2500 with the ethernet adapter. After all these years, it still works fine, and cartridges are still easy and cheap to get. The biggest problem I have is that Apple didn't write an OS X driver for it, so unless I'm printing out of a classic application, I'm stuck using the Lexmark that came bundled with the iMac. What a waste.
When I bought a new (classic) iMac, a year ago, I bought a copy of VPC5 with XP primarily because my kids wanted to use a webcam someone had given them that wouldn't work with a Mac. To our great disappointment, I found that VPC didn't pick up the USB connection. Then I tried a digital camera that was set up for Windows. Likewise, VPC wouldn't recognize the USB link. Aside from printers, I found that VPC wouldn't recognize any Windows USB peripherals I could get my hands on. I ended up returning VPC for a refund for just that reason. Still, I'd consider it again if the new version gave thorough support for Windows USB.
The court cases in question may help clarify some legal principles about the meaning of "ownership," but they won't effect the ability of people to purchase professionally third-party editted versions of movies in the long run. The reason, as usual, is technological.
My understanding of how Clean Flicks operates is that they purchase VHS copies of of movies and physically remove the "objectionable" segments of videotape from the cassette for their clients (the old-fashioned form of editting). So what they are doing is akin to buying a copy of Playboy magazine for a prude and ripping out the pages that would offend your client before delivering it.
The courts will ultimately make some kind of judgement about whether that practice is legal, but it's a moot point. By the time these litigants have exhausted all the inevitable appeals, movies will no longer be distributed on videotape, and I am not aware of any means of physically editting a standard DVD that will allow it to be played again.
The question of whether a copy of a DVD can be made, editted, burned and sold (along with the DVD that it was copied from), will also be moot by the time it is adjudicated, because it will be much simpler to develop a playback system that will only allow a DVD to be played when it is accompanied by a third-party set of edit commands (to be downloaded from the censor of your choice). Even if a DVD is somehow setup to prevent jumping forward through objectionable parts, use of a TIVO-like buffer will allow the edit instructions to be followed anyway.
After a great deal of turmoil, what is most likely to happen is that the movie producers will come to appreciate that THEY can charge an added premium for DVD's that come originally equipped with alternate edits that can be selectively blocked by the end user. Given a choice between letting other businesses profit off of after-market editting instructions, or selling the service themselves, the producers will inevitably chose to pre-empt the after-market and make a few extra bucks.
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I'm afraid that acceleration isn't the magic bullet that breaks through the paradoxes of relativistic velocities, though intuitively it seems to. Acceleration changes velocity, yes, but the same acceleration that raises my velocity with respect to one object decreases it with respect to another. To use your example of the space shuttle, it is better to consider the shuttle in relationship to the space station. When it is ready to leave the station and return to earth, it points away from the station and accelerates, increasing its velocity relative to the station, and experiencing all the effects of acceleration. Except that, the whole manuver is vectored specifically to decrease its orbital velocity, dropping it out of orbit.
So which is it? Does acceleration increase or decrease velocity? Earthly intuition tells me that the answer is obvious: if I'm hitting the accelerator, I'm increasing my velocity; if I'm hitting the brakes, I'm decreasing velocity.
But earthly intuition learned at the bottom of a massive gravity well isn't much help in understanding relativistic velocities. In a universe filled with an infinite number of objects, any acceleration changes my vector with all of those objects, increasing my velocity relative to some and decreasing it relative to others.
What the special theory of reletivity describes is not what objectively happens to me as I accelerate, but how two objects manifest themselves to each other at different shared velocities, regardless of which one is assumed to have "accelerated" (because what from one perspective may seem obviously to be acceleration may seem just as obviously to be deceleration from another perspective).
Intuition is a powerful prison. Given two objects in space converging at a shared velocity of .9 c, one a planet sized object and the other a subatomic particle, I will invariably assume that the massive object is at rest (or nearly at rest) and the subatomic particle is in a "high energy" state. Particularly if I am familiar with the special theory of relativity, I will "know" that it would be impossible to accelerate the planet to .9 c. So, it must be the subatomic particle that has been accelerated.
Except that, to the special theory, it doesn't matter how velocity is achieved. An observation made from either object would show an object approaching at .9 c, and the relativistic changes in mass, time, length, whatever, would be perceived accordingly. Which means, of course, that the observation of the planet by the particle would indicate an incredible energy state.
But then, isn't that the problem with cosmic rays? Given their velocity at even such a miniscule mass, their energy state is too high to be credible. So, relativistically speaking, cosmic rays are just as problematic as space ships or even planets traveling at near light speed.
Except that the special theory of relativity doesn't really directly address the acceleration of objects. What it addresses is the observation of objects that share a high velocity. Indirectly, it may tell you that, if you boost an object with a quantity of energy that would seem sufficient to take it over light speed, you will nonetheless measure its velocity as being less that c. Yet, the boost energy is still there, not lost to friction. Your object will hit with a force out of proportion to its measured speed, which we take to mean that it must be more massive than it was before you accelerated it.
But the special theory doesn't care what gets accelerated. For all the special theory cares, two objects blinking into existence with a shared velocity of .9 c isn't a problem. The special theory will predict how they will observe each other and what their impact on each other would be, but it doesn't really care how their relative velocity comes about, or which one is "really" in motion.
Whenever I run across a discussion of light speed or near-light speed travel, I always find myself asking, relative to what? Are people assuming that an object can be "at rest" with respect to the universe, such that it can then accelerate to a near-light speed? That would seem to be the tacit assumption of such discussions, because the only other alternative is that "velocity" is a vector relationship between any two objects. If that is the case, then any one object is at any given moment "traveling" at any number of velocities, depending on how many other objects in the universe you "relate" it to. And while our everyday experience tells us that mostly we are at rest - or close to it - with respect to our immediate surroundings, on the cosmic scale, and given the range of particles moving through this universe, it would seem pretty obvious that some of our exisiting velocities are already pretty close to light speed, even if those relationships are pretty far removed from us. To assume we are "at rest" and those other objects are "high energy" is pretty self-centered, which is intuitive and generally works for us, but doesn't really have a basis in science.
If you pay attention to what Einstein actually said in the Special Theory of Relativity, much of the "rules" have more to do with what an observer sees than with what actually happens with the object being observed.
This is no small thing. Imagine for a moment that a particle accelerator on earth has fired a subatomic particle into space at an observed velocity of 99.999% of the speed of light. Of course, we would only consider the acceleration of a subatomic particle to such speeds because Einstein's theory tells us that, since mass increases with velocity, only the most infinitesmal particle can be so accelerated without impossible expenditures of energy.
Except.
From the perspective of that subatomic particle whizzing off into space, the earth is observed as having the same velocity. In fact, velocity is properly always a relationship between two objects, not a property possessed by one object (and then "objectively" observed by another).
And if the earth is observed as traveling at 99.999% of the speed of light, then it, too, must have gone through a similar increase in mass.
The fact is, some of Einstein's rules have to do mainly with observation - with our ability to perceive - and particularly with the limits of using light as a means of perceiving objects that we are in a relationship of motion with.
More rules may yet be needed.
Ironic, ain't it.
Yah, like when Apple "acquired" NeXT.
That's not done because they're cheap. It's because there's a loophole in most anti-billboard laws that you can literally drive a semi through.
I can see it now . . . .
In doing some reading on Einstein's General Theory, I ran across the idea that Einstein's theory of how time dilates in the presence of an intense gravitational field could be proven by a red-shift in light affected by that gravitational field, the light functioning as a "clock" that would shift its spectrum in direct relationship with the gravitational time distortion.
Fine, I thought. Light does make a pretty reliable and observable clock. So, what does that mean for the Special Theory? Well, for objects moving away from each other, no problem. At relativistic velocities, there would be a red shift, which would fit with Einstein's theory of time dilation. However, since the Special Theory suggests dilation as the only relativistic time distortion caused by high velocity, any blue shift experienced by converging objects is really problematic. Blue-shifted light would indicate a contraction of time, something that the Special Theory doesn't consider at all. But maybe we should.
Do a few thought problems, and it becomes clear that, at least with regard to velocity, time dilation is but one side of a two-sided Doppler coin.
The Special Theory is great, but maybe not the last word, even in dealing with just velocity effects. It doesn't pay much attention to vectors. It hints at but doesn't really address the possibility that, when two objects have a relationship of extreme velocity, what is most distorted by relativistic effects is not either object's length, mass, or passage through time, but each object's ability to use light to "observe" the other, particularly with regard to its location and velocity.
After one hundred years of digesting the Special Theory, we really ought to be doing more than creating more dazzling illustrations of it. It needs correcting and refining, too.
I think it is interesting that, though the U.S. frequently is equated with unbridled free markets, there is the persistent residue of a different economic model that can still be found in lots of small towns and a few tight-knit urban neighborhoods. I don't have a label for it, but I've seen it at work. The small town/neighborhood model can be really determined about discouraging competition. Small town culture can find lots of ways to undercut the opening of a business that would undercut an existing business. Likewise, small town culture often puts a lot of pressure on locals to put up with being gouged by a local business, even though there is a better deal available, a few miles away. Yes, there is a price to pay for such parochialism, but likewise for globalism.
You're not that far off of describing the search engine I'd really like to see, sort of a "Name that Tune" search engine. Instead of inputting a text string, you would be able to put in a musical notation string and have the search engine return a listing of tunes that contain (or begin with, or end with, or repeat) that string. It would be useful for trying to deal (probably unsuccessfully) with those snippets of music that occasionally create an endless loop in your head. It would also help tunesmiths avoid inadvertent plagarism. You could put in the "new" tune you just composed and be reminded that it was actually an old tune you heard once at a party ten years ago.
The most dependable printer I've ever had is a Stylewriter 2500 with the ethernet adapter. After all these years, it still works fine, and cartridges are still easy and cheap to get. The biggest problem I have is that Apple didn't write an OS X driver for it, so unless I'm printing out of a classic application, I'm stuck using the Lexmark that came bundled with the iMac. What a waste.
When I bought a new (classic) iMac, a year ago, I bought a copy of VPC5 with XP primarily because my kids wanted to use a webcam someone had given them that wouldn't work with a Mac. To our great disappointment, I found that VPC didn't pick up the USB connection. Then I tried a digital camera that was set up for Windows. Likewise, VPC wouldn't recognize the USB link. Aside from printers, I found that VPC wouldn't recognize any Windows USB peripherals I could get my hands on. I ended up returning VPC for a refund for just that reason. Still, I'd consider it again if the new version gave thorough support for Windows USB.
The court cases in question may help clarify some legal principles about the meaning of "ownership," but they won't effect the ability of people to purchase professionally third-party editted versions of movies in the long run. The reason, as usual, is technological. My understanding of how Clean Flicks operates is that they purchase VHS copies of of movies and physically remove the "objectionable" segments of videotape from the cassette for their clients (the old-fashioned form of editting). So what they are doing is akin to buying a copy of Playboy magazine for a prude and ripping out the pages that would offend your client before delivering it. The courts will ultimately make some kind of judgement about whether that practice is legal, but it's a moot point. By the time these litigants have exhausted all the inevitable appeals, movies will no longer be distributed on videotape, and I am not aware of any means of physically editting a standard DVD that will allow it to be played again. The question of whether a copy of a DVD can be made, editted, burned and sold (along with the DVD that it was copied from), will also be moot by the time it is adjudicated, because it will be much simpler to develop a playback system that will only allow a DVD to be played when it is accompanied by a third-party set of edit commands (to be downloaded from the censor of your choice). Even if a DVD is somehow setup to prevent jumping forward through objectionable parts, use of a TIVO-like buffer will allow the edit instructions to be followed anyway. After a great deal of turmoil, what is most likely to happen is that the movie producers will come to appreciate that THEY can charge an added premium for DVD's that come originally equipped with alternate edits that can be selectively blocked by the end user. Given a choice between letting other businesses profit off of after-market editting instructions, or selling the service themselves, the producers will inevitably chose to pre-empt the after-market and make a few extra bucks.