The Meaning of Life, the Universe, and Everything.
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Now, I'm not too good at Physics, usually gives me a headache, yet I like thinking about it nonetheless.
Feel free to use this thread to talk about any variety of physics you want. But I have a specific couple of questions in mind at the moment to get the ball rolling....
1. I live on the fifteenth floor of an apartment building and recently the elevator has been making a few disturbing sounds. I'm a little concerned that maybe a cable will snap and send me plummeting to my death. So I was wondering... if that did happen, and if I timed it just right, would jumping right before the elevator hit the ground actually help at all? First of all my guess is that I "could" jump, because the elevator and myself within it would be falling as one contained unit, and therefore everything within the unit would be relative...? But, would jumping actually help? My guess is no, or not much, because the speed at which I propel myself upward when jumping probably wouldn't be enough to counteract the speed of the fall....
2. This one came to mind while thinking about the aforementioned issue; a question I heard a few years ago that I've never been able to answer with any real satisfaction: If you are travelling forward in a vehicle at the speed of light and turn your headlights on, does anything happen? Here, I kinda wanna say yes; the light would turn on, but it would be contained to its source, unable to project any farther in the direction that the vehicle is travelling. My reasoning for this is that if the light did project forward as normal from its source (a source which is already travelling at light speed) then it would have to travel twice the speed of light in order to do so.... ...right?
1. Nah. Typical height of a floor is 4 metres, so 15 stories is 60 metres.
Final velocity = square root of (two multiplied by acceleration multiplied by distance plus initial velocity squared)
=sqrt(2*9.81*60 + 0) = 34.31 metres per second = 123.52 kilometres per hour.
That's how fast the elevator will be traveling when it hits the ground, neglecting any resistances. We don't know an elevator's terminal velocity so we can't calculate it with air resistance accounted for. Doesn't matter though, it'd still be bloody fast.
Average human jump speed is around three metres per second. So, if you jumped at the last minute you'd still be travelling downwards at 31 metres per second. Good thing modern elevators have safety brakes, because otherwise you'd need a closed-casket funeral.
2. Ah, relativity. IIRC, light travels at light speed regardless of the reference frame, so it'd travel the at light speed away from you from your point of view, but the same speed as you from the point of view of someone standing still. Also, you can't travel at the speed of light. If you did, when you stop you would have traveled an infinite distance and an infinite amount of time would have passed
1. Nah. Typical height of a floor is 4 metres, so 15 stories is 60 metres.
Final velocity = square root of (two multiplied by acceleration multiplied by distance plus initial velocity squared)
=sqrt(2*9.81*60 + 0) = 34.31 metres per second = 123.52 kilometres per hour.
That's how fast the elevator will be traveling when it hits the ground, neglecting any resistances. We don't know an elevator's terminal velocity so we can't calculate it with air resistance accounted for. Doesn't matter though, it'd still be bloody fast.
Average human jump speed is around three metres per second. So, if you jumped at the last minute you'd still be travelling downwards at 31 metres per second. Good thing modern elevators have safety brakes, because otherwise you'd need a closed-casket funeral.
2. Ah, relativity. IIRC, light travels at light speed regardless of the reference frame, so it'd travel the at light speed away from you from your point of view, but the same speed as you from the point of view of someone standing still. Also, you can't travel at the speed of light. If you did, when you stop you would have traveled an infinite distance and an infinite amount of time would have passed
So given the possibility that the safety breaks fail, then I guess I was right, jumping ain't gonna help. Thank you, puts my mind at ease....
Also, you can't travel at the speed of light.
lol, I know, that particular question was meant to be theoretical... ^
If you did, when you stop you would have traveled an infinite distance and an infinite amount of time would have passed
That's more than just theory now? Geez, I'm way behind on things.
In the first case, yes, I was fairly certain of that too. But in the second case, there's nothing to say that if light speed were possible then theoretically travelling at the speed of light in a vehicle designed to travel at the speed of light would kill you... so that would only be a theoretical death. I'm good with that.
2. I had this discussion with some guys at school like 3 years ago! (#memory), we got onto this subject after a discussion about if you could stop time (We believe that you would be unable to move as you are 'moving' faster that atoms and particles, but that's for another time). I believe that the light would be 'trapped' in its centre of production (the car-light) and would therefore be invisible... I think,
Nah, the light would travel away from its point of creation at the speed of light. Einstein asked the same question, and so did my 5th grade teacher who was really cool. It's all relative, but I believe that if you were to look at a man on a train travelling at the speed of light and he turned on his flashlight then the light would turn on and create a beam, but because of time dilation it would appear to you that the light and train were moving slower and because of this turning on the light on the train wouldn't make the light travelling at double the speed of light. Correct me if I'm wrong.
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All that is gold does not glitter, Not all those who wander are lost
The old that is strong does not wither, Deep roots are not reached by the frost
From the ashes a fire shall be woken, A light from the shadows shall spring
Renewed shall be the blade that was broken, The crownless again shall be king
In every case, I have no idea, what I said previously was a hypothesis made by me and a bunch of associates. Your theory seems cooler therefore it is probably true because;
I'm pretty sure the scientific consensus says that the light will move away at the speed of light, but is how would you know G1 Drift?
Rollback Post to RevisionRollBack
All that is gold does not glitter, Not all those who wander are lost
The old that is strong does not wither, Deep roots are not reached by the frost
From the ashes a fire shall be woken, A light from the shadows shall spring
Renewed shall be the blade that was broken, The crownless again shall be king
Nah, the light would travel away from its point of creation at the speed of light. Einstein asked the same question, and so did my 5th grade teacher who was really cool. It's all relative, but I believe that if you were to look at a man on a train travelling at the speed of light and he turned on his flashlight then the light would turn on and create a beam, but because of time dilation it would appear to you that the light and train were moving slower and because of this turning on the light on the train wouldn't make the light travelling at double the speed of light. Correct me if I'm wrong.
Quote from DaBomb: light travels at light speed regardless of the reference frame, so it'd travel the at light speed away from you from your point of view, but the same speed as you from the point of view of someone standing still
And that is the dilemma I've got with this.... Ok, so in theory, if your sitting in the vehicle travelling at the speed of light and you turn your headlights on, the light appears to project ahead of you as normal from your own perspective... (because apparently light travels at light speed regardless of its reference frame) But I still cant see how that's possible... I mean, How can that happen without that same projection of light being observed from an outside point of view as well as from the perspective of the person in the vehicle.
And that is the dilemma I've got with this.... Ok, so in theory, if your sitting in the vehicle travelling at the speed of light and you turn your headlights on, the light appears to project ahead of you as normal from your own perspective... (because apparently light travels at light speed regardless of its reference frame) But I still cant see how that's possible... I mean, How can that happen without that same projection of light being observed from an outside point of view as well as from the perspective of the person in the vehicle.
Okay. You turn on the headlights and the light moves away from you at the speed of light, you take measurements on it. An observer takes measurement on the car and the speed of light. What would happen would be, because relativity, you and the observer would disagree on the times involved. This is relativity, and it means that no laws would be broken.
Quantum Mechanics... nipping us in the butt again.
"Erwin! Stop staring at the cat!"
"But mum! If I look away then Tiddles will die!"
Gotta love bad science puns
Those poor cats...
Actually, quantum mechanics is separate from this. The theory of relativity has to do with the bigger picture of space while quantum mechanics works on topics that are smaller than an atom. The combining of the two, a so called "Theory of Everything," is one of the most sought after discoveries in science today since we'd be able to explain everything from the largest galaxy to the smallest parts of an atom.
Okay. You turn on the headlights and the light moves away from you at the speed of light, you take measurements on it. An observer takes measurement on the car and the speed of light. What would happen would be, because relativity, you and the observer would disagree on the times involved. This is relativity, and it means that no laws would be broken.
Ah yes, that.... I did hear about a certain experiment that was run by NASA on a trip to the ISS station (I think), where astronauts brought an atomic clock on board of the Space Shuttle while an identical clock was left on earth, both running at exactly the same time. Apparently the clock that returned from space was running behind a few seconds because time on the space shuttle had slowed down slightly because of the speed the craft was travelling. The faster you travel the more time slows down.... So yeah, I guess that's a plausible explanation.
Ah yes, that.... I did hear about a certain experiment that was run by NASA on a trip to the ISS station (I think), where astronauts brought an atomic clock on board of the Space Shuttle while an identical clock was left on earth, both running at exactly the same time. Apparently the clock that returned from space was running behind a few seconds because time on the space shuttle had slowed down slightly because of the speed the craft was travelling. The faster you travel the more time slows down.... So yeah, I guess that's a plausible explanation.
It best be a plausible explanation because a big chunk of modern science is based off it.
To conclude, everybody would say that the light was going at the speed of light, but because of time dilation they would not agree on the time. If you want to look into more this link might help.
Rollback Post to RevisionRollBack
All that is gold does not glitter, Not all those who wander are lost
The old that is strong does not wither, Deep roots are not reached by the frost
From the ashes a fire shall be woken, A light from the shadows shall spring
Renewed shall be the blade that was broken, The crownless again shall be king
It best be a plausible explanation because a big chunk of modern science is based off it.
Well, no, just plausible at best really. I mean, the thing is, spacetime should get warped at speeds like that, so the laws of nature as we know them no longer apply, it's therefore impossible to predict what would actually happen in the opening post scenario, even with our modern science. But as I mentioned, I still like to think about it nonetheless. Always good to hear other peoples points of view.
Well, no, just plausible at best really. I mean, the thing is, spacetime should get warped at speeds like that, so the laws of nature as we know them no longer apply, it's therefore impossible to predict what would actually happen in the opening post scenario, even with our modern science. But as I mentioned, I still like to think about it nonetheless. Always good to hear other peoples points of view.
The original post situation is impossible. Nothing with mass can travel at the speed of light. The idea of the original post is that the warping of space time makes it so that nothing goes past the speed of light, one of the ideas of the theory of relativity. Einstein's theory makes up the basis of modern science, it's been proved that space time warps at great speeds. Time dilation is an actual 100% real thing. Also, the theory of relativity is the law of nature, and it very much applies in that situation. It's all but a fact that that is how the situation would turn out (say the train is travelling at 1/2 the speed of light, that's much easier to do) and the idea that that situation creates is one of the ideas that makes up the basis of modern science.
Edit: This guy is the world's greatest time traveler.
The original post situation is impossible. maybe,for now.
Nothing with mass can travel at the speed of light. Yet. I hope you are aware that the world was believed to be flat until it was proven otherwise.
The idea of the original post is that the warping of space time makes it so that nothing goes past the speed of light, one of the ideas of the theory of relativity. You mean the idea I had in mind when I wrote the original post? Nah, I was speculating on an unanswered questions and eager to hear what others had to say about it. Fortunately there has been no shortage of that. I wasn't really expecting someone to know the answer without any doubt because, you know, we can't travel at the speed of light.
Einstein's theory makes up the basis of modern science. Yes
it's been proved that space time warps at great speeds. True, I may have even mentioned it at some point...
Time dilation is an actual 100% real thing. Also, the theory of relativity is the law of nature, and it very much applies in that situation. well, sure, that's all we have to go on atm.
It's all but a fact that that is how the situation would turn out. I should think not a fact, because, as it has been made clear many times, we can not travel at light speed in order to be 100% certain of this, and therefore we still only have a theory based on current knowledge. But the theory does sound right, doesn't it?
(say the train is travelling at 1/2 the speed of light, that's much easier to do) and the idea that that situation creates is one of the ideas that makes up the basis of modern science. Einstein's preferred method of travel was a train.
Edit: This guy is the world's greatest time traveler.
And how is it that you may know that these theories are facts? Well, simple really, and in the words of some science teacher somewhere out there; "because we've never observed a case otherwise...."
That's more than just theory now? Geez, I'm way behind on things.
Yeah, time dilation and length contraction work on the same factor:
G = sqrt(1-v^2/c^2)
Where v is the speed you're travelling and c is the speed of light.
From the point of view of the person on the train, stationary lengths and distances would contract to d*G, where d is the distance, and time of stationary objects would expand to t/G, where t is the time. If you traveled at the speed of light:
v = c
G = sqrt(1-v^2/c^2) = sqrt(1-c^2/c^2) =sqrt(1-1) = sqrt(0) = 0
So, if you traveled the speed of light, from your point of view the universe would contract into a 2D plane perpendicular to your velocity, and by travelling through that plane you would have traveled an infinite distance. Stationary time would be the time you traveled at the speed of light divided by zero, so you would have traveled for an infinite length of time. This is why you can't travel the speed of light. You would need an infinite amount of energy and there's presumably only a finite amount of energy in the universe.
I thought it would be easier just to respond with Bold in your Quote:
And how is it that you may know that these theories are facts? Well, simple really, and in the words of some science teacher somewhere out there; "because we've never observed a case otherwise...."
It is impossible to travel at the speed of light. To suggest the possibility otherwise goes against everything modern science stands on... People bring up the fact that the world used to be thought of as flat, but that's only because nobody ever tried to prove otherwise. Many scientists over many years have rigorously tried to find a way to disprove this theory, but none have found any way to do so. They are two entirely separate situations and are the same in very few ways.
It is an answered question. the question has been asked for around 100 years now and Einstein provided his answer a little less than 100 years ago. The answer to the problem, if we were to be very strict on having the speed the train was going at be the speed of light, would be that the situation is absolutely impossible. My ideas are based off of the idea that light moving away from a moving source should, according to common logic, be breaking the cosmic speed limit.
Also, a response to your final comment. A better wording might be, "never been proved otherwise," as action is much more efficient than observation. While it's nice to think that there may be a massive paradigm shift right around the corner, the truth is that it's really not going to happen. Modern scientific theories go through such rigorous testing and continuous attempts at disproof that we can be relatively (no pun intended) sure that our theories our correct.
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All that is gold does not glitter, Not all those who wander are lost
The old that is strong does not wither, Deep roots are not reached by the frost
From the ashes a fire shall be woken, A light from the shadows shall spring
Renewed shall be the blade that was broken, The crownless again shall be king
Anyway... I do know that everything takes energy, but still, I'm fairly certain there have been other presumably impossible accomplishments accomplished by discovering other ideas.
In the first case, yes, I was fairly certain of that too. But in the second case, there's nothing to say that if light speed were possible then theoretically travelling at the speed of light in a vehicle designed to travel at the speed of light would kill you... so that would only be a theoretical death. I'm good with that.
Without going into the numbers, it's generally regarded that the faster you go and the closer you get to the speed of light the more mass you acquire. It's assumed as you reach that speed you would or could basically acquire infinite mass. It's way massless (or near massless) particles like photons and smaller are the only known particles - theoretical or otherwise - to reach those speeds (though I could be wrong). Like-wise, the mass you acquire the more energy you would need to maintain acceleration.
Ignoring a source of energy, it can surmised that anything you use to accelerate you and the vehicle to the speed required to reach the speed of light in an observable way will be going so fast that the acceleration will effect you - the passenger - with ever increasing G-forces noticeable most in initial stages. These forces would probably crush you. As well, the relative speed you're travelling may kill you through the same principle.
Assuming that somehow acceleration forces won't kill you, then the increase in mass will; but this stretches the scenario but is funner to think about. At some point you and the vehicle would acquire so much mass on its way to infinity in both mass and energy you would probably collapse in on yourself from gravitational forces created in the vehicle and the pilot and form your own small black-hole. Here you would go out with an exotic crunch as you're collapsed in on yourself and torn and stretched as your small point of highly concentrated gravity creates a nice deep black hole.
In short, you'd be dead before the phenomenon of relative light-speeds can be observed or dead before you can report it - if you're even capable of reporting it in the first place.
Perhaps as you die you might experience the Star Gate sequence from 2001: A Space Odyssey
Or maybe you get to experience the inside of a Black Hole before you die without the bother of entering it, unlike Interstellar.
Now, I'm not too good at Physics, usually gives me a headache, yet I like thinking about it nonetheless.
Feel free to use this thread to talk about any variety of physics you want. But I have a specific couple of questions in mind at the moment to get the ball rolling....
1. I live on the fifteenth floor of an apartment building and recently the elevator has been making a few disturbing sounds. I'm a little concerned that maybe a cable will snap and send me plummeting to my death. So I was wondering... if that did happen, and if I timed it just right, would jumping right before the elevator hit the ground actually help at all? First of all my guess is that I "could" jump, because the elevator and myself within it would be falling as one contained unit, and therefore everything within the unit would be relative...? But, would jumping actually help? My guess is no, or not much, because the speed at which I propel myself upward when jumping probably wouldn't be enough to counteract the speed of the fall....
2. This one came to mind while thinking about the aforementioned issue; a question I heard a few years ago that I've never been able to answer with any real satisfaction: If you are travelling forward in a vehicle at the speed of light and turn your headlights on, does anything happen? Here, I kinda wanna say yes; the light would turn on, but it would be contained to its source, unable to project any farther in the direction that the vehicle is travelling. My reasoning for this is that if the light did project forward as normal from its source (a source which is already travelling at light speed) then it would have to travel twice the speed of light in order to do so.... ...right?
1. Nah. Typical height of a floor is 4 metres, so 15 stories is 60 metres.
Final velocity = square root of (two multiplied by acceleration multiplied by distance plus initial velocity squared)
=sqrt(2*9.81*60 + 0) = 34.31 metres per second = 123.52 kilometres per hour.
That's how fast the elevator will be traveling when it hits the ground, neglecting any resistances. We don't know an elevator's terminal velocity so we can't calculate it with air resistance accounted for. Doesn't matter though, it'd still be bloody fast.
Average human jump speed is around three metres per second. So, if you jumped at the last minute you'd still be travelling downwards at 31 metres per second. Good thing modern elevators have safety brakes, because otherwise you'd need a closed-casket funeral.
2. Ah, relativity. IIRC, light travels at light speed regardless of the reference frame, so it'd travel the at light speed away from you from your point of view, but the same speed as you from the point of view of someone standing still. Also, you can't travel at the speed of light. If you did, when you stop you would have traveled an infinite distance and an infinite amount of time would have passed
You'd be dead in both cases.
That's what would happen.
My DeviantArt, so sexy
I actually have no clue what I'm talking about but I just wanted to contribute and maybe learn something.
With 1 I'm pretty sure, no matter what, the roof of the elevator would collapse on you and you'd die.
Even if it didn't, the elevator would be falling way too fast for you to jump.
Even if you were able to jump, then you'd still die because it would be the equivalent of hitting the ground (I think..?)
So given the possibility that the safety breaks fail, then I guess I was right, jumping ain't gonna help. Thank you, puts my mind at ease....
lol, I know, that particular question was meant to be theoretical... ^
That's more than just theory now? Geez, I'm way behind on things.
In the first case, yes, I was fairly certain of that too. But in the second case, there's nothing to say that if light speed were possible then theoretically travelling at the speed of light in a vehicle designed to travel at the speed of light would kill you... so that would only be a theoretical death. I'm good with that.
Nah, the light would travel away from its point of creation at the speed of light. Einstein asked the same question, and so did my 5th grade teacher who was really cool. It's all relative, but I believe that if you were to look at a man on a train travelling at the speed of light and he turned on his flashlight then the light would turn on and create a beam, but because of time dilation it would appear to you that the light and train were moving slower and because of this turning on the light on the train wouldn't make the light travelling at double the speed of light. Correct me if I'm wrong.
All that is gold does not glitter, Not all those who wander are lost
The old that is strong does not wither, Deep roots are not reached by the frost
From the ashes a fire shall be woken, A light from the shadows shall spring
Renewed shall be the blade that was broken, The crownless again shall be king
I'm pretty sure the scientific consensus says that the light will move away at the speed of light, but is how would you know G1 Drift?
All that is gold does not glitter, Not all those who wander are lost
The old that is strong does not wither, Deep roots are not reached by the frost
From the ashes a fire shall be woken, A light from the shadows shall spring
Renewed shall be the blade that was broken, The crownless again shall be king
This might just be a coincidence, but my avatar's name if Drift and is commonly referred to as G1 Drift. G1 stands for Generation 1.
Drift is on the right
All that is gold does not glitter, Not all those who wander are lost
The old that is strong does not wither, Deep roots are not reached by the frost
From the ashes a fire shall be woken, A light from the shadows shall spring
Renewed shall be the blade that was broken, The crownless again shall be king
And that is the dilemma I've got with this.... Ok, so in theory, if your sitting in the vehicle travelling at the speed of light and you turn your headlights on, the light appears to project ahead of you as normal from your own perspective... (because apparently light travels at light speed regardless of its reference frame) But I still cant see how that's possible... I mean, How can that happen without that same projection of light being observed from an outside point of view as well as from the perspective of the person in the vehicle.
Okay. You turn on the headlights and the light moves away from you at the speed of light, you take measurements on it. An observer takes measurement on the car and the speed of light. What would happen would be, because relativity, you and the observer would disagree on the times involved. This is relativity, and it means that no laws would be broken.
All that is gold does not glitter, Not all those who wander are lost
The old that is strong does not wither, Deep roots are not reached by the frost
From the ashes a fire shall be woken, A light from the shadows shall spring
Renewed shall be the blade that was broken, The crownless again shall be king
Those poor cats...
Actually, quantum mechanics is separate from this. The theory of relativity has to do with the bigger picture of space while quantum mechanics works on topics that are smaller than an atom. The combining of the two, a so called "Theory of Everything," is one of the most sought after discoveries in science today since we'd be able to explain everything from the largest galaxy to the smallest parts of an atom.
Edit: Here's a drawing.
All that is gold does not glitter, Not all those who wander are lost
The old that is strong does not wither, Deep roots are not reached by the frost
From the ashes a fire shall be woken, A light from the shadows shall spring
Renewed shall be the blade that was broken, The crownless again shall be king
Ah yes, that.... I did hear about a certain experiment that was run by NASA on a trip to the ISS station (I think), where astronauts brought an atomic clock on board of the Space Shuttle while an identical clock was left on earth, both running at exactly the same time. Apparently the clock that returned from space was running behind a few seconds because time on the space shuttle had slowed down slightly because of the speed the craft was travelling. The faster you travel the more time slows down.... So yeah, I guess that's a plausible explanation.
It best be a plausible explanation because a big chunk of modern science is based off it.
To conclude, everybody would say that the light was going at the speed of light, but because of time dilation they would not agree on the time. If you want to look into more this link might help.
All that is gold does not glitter, Not all those who wander are lost
The old that is strong does not wither, Deep roots are not reached by the frost
From the ashes a fire shall be woken, A light from the shadows shall spring
Renewed shall be the blade that was broken, The crownless again shall be king
Well, no, just plausible at best really. I mean, the thing is, spacetime should get warped at speeds like that, so the laws of nature as we know them no longer apply, it's therefore impossible to predict what would actually happen in the opening post scenario, even with our modern science. But as I mentioned, I still like to think about it nonetheless. Always good to hear other peoples points of view.
The original post situation is impossible. Nothing with mass can travel at the speed of light. The idea of the original post is that the warping of space time makes it so that nothing goes past the speed of light, one of the ideas of the theory of relativity. Einstein's theory makes up the basis of modern science, it's been proved that space time warps at great speeds. Time dilation is an actual 100% real thing. Also, the theory of relativity is the law of nature, and it very much applies in that situation. It's all but a fact that that is how the situation would turn out (say the train is travelling at 1/2 the speed of light, that's much easier to do) and the idea that that situation creates is one of the ideas that makes up the basis of modern science.
Edit: This guy is the world's greatest time traveler.
All that is gold does not glitter, Not all those who wander are lost
The old that is strong does not wither, Deep roots are not reached by the frost
From the ashes a fire shall be woken, A light from the shadows shall spring
Renewed shall be the blade that was broken, The crownless again shall be king
And how is it that you may know that these theories are facts? Well, simple really, and in the words of some science teacher somewhere out there; "because we've never observed a case otherwise...."
Yeah, time dilation and length contraction work on the same factor:
G = sqrt(1-v^2/c^2)
Where v is the speed you're travelling and c is the speed of light.
From the point of view of the person on the train, stationary lengths and distances would contract to d*G, where d is the distance, and time of stationary objects would expand to t/G, where t is the time. If you traveled at the speed of light:
v = c
G = sqrt(1-v^2/c^2) = sqrt(1-c^2/c^2) =sqrt(1-1) = sqrt(0) = 0
So, if you traveled the speed of light, from your point of view the universe would contract into a 2D plane perpendicular to your velocity, and by travelling through that plane you would have traveled an infinite distance. Stationary time would be the time you traveled at the speed of light divided by zero, so you would have traveled for an infinite length of time. This is why you can't travel the speed of light. You would need an infinite amount of energy and there's presumably only a finite amount of energy in the universe.
It is impossible to travel at the speed of light. To suggest the possibility otherwise goes against everything modern science stands on... People bring up the fact that the world used to be thought of as flat, but that's only because nobody ever tried to prove otherwise. Many scientists over many years have rigorously tried to find a way to disprove this theory, but none have found any way to do so. They are two entirely separate situations and are the same in very few ways.
It is an answered question. the question has been asked for around 100 years now and Einstein provided his answer a little less than 100 years ago. The answer to the problem, if we were to be very strict on having the speed the train was going at be the speed of light, would be that the situation is absolutely impossible. My ideas are based off of the idea that light moving away from a moving source should, according to common logic, be breaking the cosmic speed limit.
Also, a response to your final comment. A better wording might be, "never been proved otherwise," as action is much more efficient than observation. While it's nice to think that there may be a massive paradigm shift right around the corner, the truth is that it's really not going to happen. Modern scientific theories go through such rigorous testing and continuous attempts at disproof that we can be relatively (no pun intended) sure that our theories our correct.
All that is gold does not glitter, Not all those who wander are lost
The old that is strong does not wither, Deep roots are not reached by the frost
From the ashes a fire shall be woken, A light from the shadows shall spring
Renewed shall be the blade that was broken, The crownless again shall be king
..........................................................................................................................................................................................
Anyway... I do know that everything takes energy, but still, I'm fairly certain there have been other presumably impossible accomplishments accomplished by discovering other ideas.
Without going into the numbers, it's generally regarded that the faster you go and the closer you get to the speed of light the more mass you acquire. It's assumed as you reach that speed you would or could basically acquire infinite mass. It's way massless (or near massless) particles like photons and smaller are the only known particles - theoretical or otherwise - to reach those speeds (though I could be wrong). Like-wise, the mass you acquire the more energy you would need to maintain acceleration.
Ignoring a source of energy, it can surmised that anything you use to accelerate you and the vehicle to the speed required to reach the speed of light in an observable way will be going so fast that the acceleration will effect you - the passenger - with ever increasing G-forces noticeable most in initial stages. These forces would probably crush you. As well, the relative speed you're travelling may kill you through the same principle.
Assuming that somehow acceleration forces won't kill you, then the increase in mass will; but this stretches the scenario but is funner to think about. At some point you and the vehicle would acquire so much mass on its way to infinity in both mass and energy you would probably collapse in on yourself from gravitational forces created in the vehicle and the pilot and form your own small black-hole. Here you would go out with an exotic crunch as you're collapsed in on yourself and torn and stretched as your small point of highly concentrated gravity creates a nice deep black hole.
In short, you'd be dead before the phenomenon of relative light-speeds can be observed or dead before you can report it - if you're even capable of reporting it in the first place.
Perhaps as you die you might experience the Star Gate sequence from 2001: A Space Odyssey
Or maybe you get to experience the inside of a Black Hole before you die without the bother of entering it, unlike Interstellar.
My DeviantArt, so sexy