Evil_bOb1Join Date: 2002-07-13Member: 938Members, Squad Five Blue
<!--quoteo(post=1876616:date=Sep 23 2011, 04:07 PM:name=Align)--><div class='quotetop'>QUOTE (Align @ Sep 23 2011, 04:07 PM) <a href="index.php?act=findpost&pid=1876616"><{POST_SNAPBACK}></a></div><div class='quotemain'><!--quotec-->I'd expect the guys doing these kind of experiments to take such factors into account, if it's applicable.<!--QuoteEnd--></div><!--QuoteEEnd-->
They even took the continental drift into account :p
<!--quoteo(post=1876623:date=Sep 23 2011, 11:35 PM:name=Sops)--><div class='quotetop'>QUOTE (Sops @ Sep 23 2011, 11:35 PM) <a href="index.php?act=findpost&pid=1876623"><{POST_SNAPBACK}></a></div><div class='quotemain'><!--quotec-->The time difference is due to the jet stream, think of the atmosphere as an ocean with currents. (because that is exactly what it is)<!--QuoteEnd--></div><!--QuoteEEnd-->
I see, i never knew that until i googled it just now, i always just assumed it had to with the rotation of the planet. Learn something new every day.
<!--quoteo(post=1876636:date=Sep 24 2011, 12:34 AM:name=Nossah)--><div class='quotetop'>QUOTE (Nossah @ Sep 24 2011, 12:34 AM) <a href="index.php?act=findpost&pid=1876636"><{POST_SNAPBACK}></a></div><div class='quotemain'><!--quotec-->I see, i never knew that until i googled it just now, i always just assumed it had to with the rotation of the planet. Learn something new every day.<!--QuoteEnd--></div><!--QuoteEEnd-->
Relativity is sort of exactly why it isn't due to the rotation of the planet. Everything on the planet moves relative to the planet, the planet is the reference frame for everything on the planet.
Which is why we don't notice that we're actually whizzing round the sun at a bajillion miles an hour, and around the galactic centre even faster, and probably even faster away from the centre of the universe.
If velocity were absolute, then moving in certain directions would make you behave differently than if you moved in others, in fact you'd experience a constant force in one direction because of 'universal drag' or something causing you to stedily decelerate, which obviously doesn't happen.
X_StickmanNot good enough for a custom title.Join Date: 2003-04-15Member: 15533Members, Constellation
<!--quoteo(post=1876616:date=Sep 23 2011, 11:07 PM:name=Align)--><div class='quotetop'>QUOTE (Align @ Sep 23 2011, 11:07 PM) <a href="index.php?act=findpost&pid=1876616"><{POST_SNAPBACK}></a></div><div class='quotemain'><!--quotec-->I'd expect the guys doing these kind of experiments to take such factors into account, if it's applicable.
I don't think any collider was involved?<!--QuoteEnd--></div><!--QuoteEEnd-->
<i>That's</i> the part of my argument you challenge?
<!--quoteo(post=1876648:date=Sep 24 2011, 01:46 AM:name=X_Stickman)--><div class='quotetop'>QUOTE (X_Stickman @ Sep 24 2011, 01:46 AM) <a href="index.php?act=findpost&pid=1876648"><{POST_SNAPBACK}></a></div><div class='quotemain'><!--quotec--><i>That's</i> the part of my argument you challenge?<!--QuoteEnd--></div><!--QuoteEEnd--> Why would I want to point out that a joke is factually incorrect...?
The reason rotation doesn't matter for aircraft is that the aircraft "rotates to the east" at the exact same speed as the surface of the earth and most of the atmosphere does when it's on the ground. So even when it (and we ourselves, for that matter) is standing still, it's still "moving to the east" at high speed.
Maybe I'm making a mistake somewhere, but I could imagine the earth's rotational speed could make an extraordinarily tiny difference for measurements of light speed. Consider this: A photon moves at the speed of light at all times. Never any slower, never any faster. Any test setup on the surface of the earth, at the equator, "moves east" constantly, due to the earth's rotation. That speed is ca. 463 m/s, which is a tiny fraction of the speed of light. But if you're firing photons west-east, the detecter is moving AWAY from the photons at that speed, whereas if you're firing them east-west it's moving towards them. Thus there should be a tiny difference in the time it takes for them to travel.
But the difference would be extremely tiny. We're talking a speed difference of something like 0,0003%. And that's under conditions designed to maximize the effects, if you weren't firing east-west or west-east, or if you weren't at the equator, the effect would be even smaller. So that probably wouldn't account for this.
Moreover, if something like that DOES matter, it sound implausible to me that they'd make that mistake. Assumptions of infallibility are bad science, but this IS CERN we're talking about - they're no amateurs at particle physics. It's not impossible they've made a very basic mistake somewhere, but it is highly unlikely.
But there's most likely a mistake SOMEWHERE. I just don't think it's something we'll be able to think of, because I we can, then so can they.
Another reason I've always been confused about the speed of light being a constant is that I thought velocity was relative. As has already been discussed, when we generally measure a speed here on earth, we measure it relative to the surface of the earth, which is spinning fast around its axis, around the sun, through the galaxy, etc. If the big bang theory is correct, the whole universe is expanding outwards. Is there really such a thing as "absolute zero speed" (which I would think would be required in order for light to have a constant speed) when our whole universe is moving? let's say this "absolute zero speed" is at the center of the universe. if you shined a flashlight from your point on earth toward the center of the universe, wouldn't the light travel much slower relative to where you are than it would if you shined it in the opposite direction?
Or, if I'm thinking about it wrong and light travels at speed c relative to where it's emitted from, then if I were standing by the side of the road and I shined a flashlight at the tail of a speeding car, wouldn't the light be traveling at c - 60mph from the perspective of the driver?
edit: I have a feeling this is where the relationship with mass and time comes in and that's why I can't wrap my mind around it.
Yeah, their speed is the same, but since they travel in opposite directions one is going to be travelling x, and the other -x, a difference of 2x. In this case, x happens to be c. What I'm saying is that there's nothing strange about the total adding up to more than c, which DiscoZombie apparently found strange.
InsaneAnomalyJoin Date: 2002-05-13Member: 605Members, Super Administrators, Forum Admins, NS1 Playtester, Forum Moderators, NS2 Developer, Constellation, NS2 Playtester, Squad Five Blue, NS2 Map Tester, Subnautica Developer, Pistachionauts, Future Perfect Developer
edited September 2011
<!--quoteo(post=1876752:date=Sep 24 2011, 03:56 PM:name=Align)--><div class='quotetop'>QUOTE (Align @ Sep 24 2011, 03:56 PM) <a href="index.php?act=findpost&pid=1876752"><{POST_SNAPBACK}></a></div><div class='quotemain'><!--quotec-->Yeah, their speed is the same, but since they travel in opposite directions one is going to be travelling x, and the other -x, a difference of 2x. In this case, x happens to be c. What I'm saying is that there's nothing strange about the total adding up to more than c, which DiscoZombie apparently found strange.<!--QuoteEnd--></div><!--QuoteEEnd-->
Except c is constant. So from the reference frame of the first photon, the second would appear to be moving away at the speed of light, and vice versa. From the reference frame of a third position, the photons would appear to be moving apart at the speed of light. Whatever your reference frame, you'll get the same measurement for the speed of light in a vacuum.
InsaneAnomalyJoin Date: 2002-05-13Member: 605Members, Super Administrators, Forum Admins, NS1 Playtester, Forum Moderators, NS2 Developer, Constellation, NS2 Playtester, Squad Five Blue, NS2 Map Tester, Subnautica Developer, Pistachionauts, Future Perfect Developer
Because at the speed of light the usual facts about relative velocity no longer hold up. It doesn't matter how fast an observer is travelling, light will always appear to travel at c.
I doubt the rotation of the Earth factors into this, considering they're firing the beam to the southeast... if they didn't account for it, it would take more time, not less.
@ Align - think of it like this - you have a giant, glowing digital clockface that reads 3:00. When you're moving relative to it, time passes 'normally', ie: 3:01 takes 1 minute. You know this because the digital numbers are emitting light, and the light is in the shape of the numbers.
Now, say you get into a spaceship and start heading out away from the clock. As you travel away from it at any speed, you experience time dilation, even if it's very minute. This is because as the photons that leave the clockface that form the numbers are trapped at the speed limit <i>c</i>, traveling away from it means that while the clock itself only takes 1 minute to change to 3:01, by the time the light catches up to you, it will have taken slightly longer (since you're expanding the gap). If you're going 0.5<i>c</i>, time according to the clockface is traveling at half speed.
If you are going exactly <i>c</i>, the numbers will never change and will forever read 3:00, because the new 'information' about time cannot catch up to you, while an observer next to the clock sees that it's 3:01, 3:30, 10:00, whatever. If you were going <i>faster</i> than <i>c</i>, time would appear to go backwards, as you catch up to the light from 2:59.
Now, in the case of the photons traveling away from each other, observing from one photon to the other will never see the other photon 'move away' from you, because the information about its position is traveling at <i>c</i>, which just happens to be your current speed. Thus, you will never observe it to go faster than <i>c</i>.
Now, one thing I've never been able to wrap my mind around are the specifics of time dilation.
Shouldn't time travel be simply illusionary? If I'm traveling at 2<i>c</i> towards another star, the Earth behind me would appear to get younger, while the star in front of me would rapidly get older. From the earth, we see stars as they were many thousands of years ago, some of which may have already exploded and died but we don't know it yet. If I travel far enough, I could observe the solar system before the earth was even formed (you know, about 5 billion lightyears), but does that mean the earth doesn't exist? No, and for every minute I went backwards relative to earth, I went a minute forward somewhere else.
This is where I don't understand the whole time dilation letting a light-speed traveler somehow age slower than others... If I returned to earth, I would accelerate FORWARD through time and thus arrive back on earth aged exactly as I should have, shouldn't I?
EDIT: I've been doing some more reading and this is pretty brain-bending stuff, but it appears that my flaw is that I'm thinking of time dilation in reference to observers, when it seems time dilation occurs because you are moving fast in relation to <i>time itself</i>. Such that were special relativity based on the frame of reference of observers, there would be no fundamental difference in one guy traveling at 0.8<i>c</i> away from a stationary guy, since velocity is meaningless without reference, it should/could appear that the stationary person is moving away from the space traveler at 0.8<i>c</i> and thus 'would' experience time dilation, but that's not the case - time dilation only occurs in the 'moving' body due to approaching the speed of light. As he approaches <i>c</i>, his movement through spacetime is effectively instantaneous, and should, I imagine, experience nothing at all, as all biological processes and even his thoughts would be slowed relative to his movement through time - at <i>c</i>, this would mean no passage of time whatsoever...
No, because as that strip clearly demonstrates, <b>xkcd is not, and has never been funny</b>. Randall Dumbroe is a egotistical math snob, we get it already.
Though you may find <a href="http://www.garfield.com/" target="_blank">this</a> or <a href="http://www.cad-comic.com/" target="_blank">this</a> to your liking.
<!--quoteo(post=1876832:date=Sep 25 2011, 05:41 AM:name=Temphage)--><div class='quotetop'>QUOTE (Temphage @ Sep 25 2011, 05:41 AM) <a href="index.php?act=findpost&pid=1876832"><{POST_SNAPBACK}></a></div><div class='quotemain'><!--quotec-->If you are going exactly <i>c</i>, the numbers will never change and will forever read 3:00, because the new 'information' about time cannot catch up to you, while an observer next to the clock sees that it's 3:01, 3:30, 10:00, whatever. If you were going <i>faster</i> than <i>c</i>, time would appear to go backwards, as you catch up to the light from 2:59.
Now, in the case of the photons traveling away from each other, observing from one photon to the other will never see the other photon 'move away' from you, because the information about its position is traveling at <i>c</i>, which just happens to be your current speed. Thus, you will never observe it to go faster than <i>c</i>.<!--QuoteEnd--></div><!--QuoteEEnd-->But I'm not talking about observing one from the other, I'm talking about the speed difference of one and the other. What you're saying actually supports what I said.
(also could you remove that dotted line, it ###### up my browser formatting)
<!--quoteo(post=1876615:date=Sep 23 2011, 05:04 PM:name=Nossah)--><div class='quotetop'>QUOTE (Nossah @ Sep 23 2011, 05:04 PM) <a href="index.php?act=findpost&pid=1876615"><{POST_SNAPBACK}></a></div><div class='quotemain'><!--quotec-->When you take a flight from europe to america and back there is a 2 hour difference in flight time because of the rotation of the earth. Since this measurement was made over a distance of 750 or so kilometers ON EARTH.<!--QuoteEnd--></div><!--QuoteEEnd--> Looks like you were on to something but for the wrong reason, the problem was they were not taking the measurement from Earth <a href="http://www.fellowgeek.com/a-Einstein%E2%80%99s-Theory-Still-Safe.html" target="_blank">http://www.fellowgeek.com/a-Einstein%E2%80...Still-Safe.html</a>
Although this hasn't been fully reviewed yet either.
<!--quoteo(post=1876832:date=Sep 25 2011, 12:41 AM:name=Temphage)--><div class='quotetop'>QUOTE (Temphage @ Sep 25 2011, 12:41 AM) <a href="index.php?act=findpost&pid=1876832"><{POST_SNAPBACK}></a></div><div class='quotemain'><!--quotec-->... Now, one thing I've never been able to wrap my mind around are the specifics of time dilation.
Shouldn't time travel be simply illusionary? If I'm traveling at 2<i>c</i> towards another star, the Earth behind me would appear to get younger, while the star in front of me would rapidly get older. From the earth, we see stars as they were many thousands of years ago, some of which may have already exploded and died but we don't know it yet. If I travel far enough, I could observe the solar system before the earth was even formed (you know, about 5 billion lightyears), but does that mean the earth doesn't exist? No, and for every minute I went backwards relative to earth, I went a minute forward somewhere else.
This is where I don't understand the whole time dilation letting a light-speed traveler somehow age slower than others... If I returned to earth, I would accelerate FORWARD through time and thus arrive back on earth aged exactly as I should have, shouldn't I?
EDIT: I've been doing some more reading and this is pretty brain-bending stuff, but it appears that my flaw is that I'm thinking of time dilation in reference to observers, when it seems time dilation occurs because you are moving fast in relation to <i>time itself</i>. Such that were special relativity based on the frame of reference of observers, there would be no fundamental difference in one guy traveling at 0.8<i>c</i> away from a stationary guy, since velocity is meaningless without reference, it should/could appear that the stationary person is moving away from the space traveler at 0.8<i>c</i> and thus 'would' experience time dilation, but that's not the case - time dilation only occurs in the 'moving' body due to approaching the speed of light. As he approaches <i>c</i>, his movement through spacetime is effectively instantaneous, and should, I imagine, experience nothing at all, as all biological processes and even his thoughts would be slowed relative to his movement through time - at <i>c</i>, this would mean no passage of time whatsoever...
...<!--QuoteEnd--></div><!--QuoteEEnd-->
I've always thought of it as light conveys more information than just em waves. Say it's the signal that tells metaphysical "clocks" to tick. So the speed of light is the speed of time. It'd be like if you took a set of instructions on a PC and ran them at a different clock speed than other instructions in the program.
In any case, the only sane thing to do when confronted by this stuff is to abandon the idea of time as a concept all together. :P At least unless your Michio Kaku or Hawking or someone who can actually comprehend.
<!--quoteo(post=1876832:date=Sep 25 2011, 05:41 AM:name=Temphage)--><div class='quotetop'>QUOTE (Temphage @ Sep 25 2011, 05:41 AM) <a href="index.php?act=findpost&pid=1876832"><{POST_SNAPBACK}></a></div><div class='quotemain'><!--quotec-->No, because as that strip clearly demonstrates, <b>xkcd is not, and has never been funny</b>. Randall Dumbroe is a egotistical math snob, we get it already.
Though you may find <a href="http://www.garfield.com/" target="_blank">this</a> or <a href="http://www.cad-comic.com/" target="_blank">this</a> to your liking.<!--QuoteEnd--></div><!--QuoteEEnd-->
Ehh, I figure anyone with a brain will get most of them.
I have zero mathematics training and I still get most of them.
Comments
They even took the continental drift into account :p
I'm intrigued but remain skeptical. I look forward to additional experiments being run and new data being released!
I see, i never knew that until i googled it just now, i always just assumed it had to with the rotation of the planet. Learn something new every day.
Relativity is sort of exactly why it isn't due to the rotation of the planet. Everything on the planet moves relative to the planet, the planet is the reference frame for everything on the planet.
Which is why we don't notice that we're actually whizzing round the sun at a bajillion miles an hour, and around the galactic centre even faster, and probably even faster away from the centre of the universe.
If velocity were absolute, then moving in certain directions would make you behave differently than if you moved in others, in fact you'd experience a constant force in one direction because of 'universal drag' or something causing you to stedily decelerate, which obviously doesn't happen.
I don't think any collider was involved?<!--QuoteEnd--></div><!--QuoteEEnd-->
<i>That's</i> the part of my argument you challenge?
<img src="http://imgs.xkcd.com/comics/neutrinos.png" border="0" class="linked-image" />
Why would I want to point out that a joke is factually incorrect...?
Maybe I'm making a mistake somewhere, but I could imagine the earth's rotational speed could make an extraordinarily tiny difference for measurements of light speed. Consider this: A photon moves at the speed of light at all times. Never any slower, never any faster. Any test setup on the surface of the earth, at the equator, "moves east" constantly, due to the earth's rotation. That speed is ca. 463 m/s, which is a tiny fraction of the speed of light. But if you're firing photons west-east, the detecter is moving AWAY from the photons at that speed, whereas if you're firing them east-west it's moving towards them. Thus there should be a tiny difference in the time it takes for them to travel.
But the difference would be extremely tiny. We're talking a speed difference of something like 0,0003%. And that's under conditions designed to maximize the effects, if you weren't firing east-west or west-east, or if you weren't at the equator, the effect would be even smaller. So that probably wouldn't account for this.
Moreover, if something like that DOES matter, it sound implausible to me that they'd make that mistake. Assumptions of infallibility are bad science, but this IS CERN we're talking about - they're no amateurs at particle physics. It's not impossible they've made a very basic mistake somewhere, but it is highly unlikely.
But there's most likely a mistake SOMEWHERE. I just don't think it's something we'll be able to think of, because I we can, then so can they.
Or, if I'm thinking about it wrong and light travels at speed c relative to where it's emitted from, then if I were standing by the side of the road and I shined a flashlight at the tail of a speeding car, wouldn't the light be traveling at c - 60mph from the perspective of the driver?
edit: I have a feeling this is where the relationship with mass and time comes in and that's why I can't wrap my mind around it.
Discozombie - In your 60ph car + flashlight example, the light is still going at c, only its redshifted (wavelength changed).
What I'm saying is that there's nothing strange about the total adding up to more than c, which DiscoZombie apparently found strange.
What I'm saying is that there's nothing strange about the total adding up to more than c, which DiscoZombie apparently found strange.<!--QuoteEnd--></div><!--QuoteEEnd-->
Except c is constant. So from the reference frame of the first photon, the second would appear to be moving away at the speed of light, and vice versa. From the reference frame of a third position, the photons would appear to be moving apart at the speed of light. Whatever your reference frame, you'll get the same measurement for the speed of light in a vacuum.
@ Align - think of it like this - you have a giant, glowing digital clockface that reads 3:00. When you're moving relative to it, time passes 'normally', ie: 3:01 takes 1 minute. You know this because the digital numbers are emitting light, and the light is in the shape of the numbers.
Now, say you get into a spaceship and start heading out away from the clock. As you travel away from it at any speed, you experience time dilation, even if it's very minute. This is because as the photons that leave the clockface that form the numbers are trapped at the speed limit <i>c</i>, traveling away from it means that while the clock itself only takes 1 minute to change to 3:01, by the time the light catches up to you, it will have taken slightly longer (since you're expanding the gap). If you're going 0.5<i>c</i>, time according to the clockface is traveling at half speed.
If you are going exactly <i>c</i>, the numbers will never change and will forever read 3:00, because the new 'information' about time cannot catch up to you, while an observer next to the clock sees that it's 3:01, 3:30, 10:00, whatever. If you were going <i>faster</i> than <i>c</i>, time would appear to go backwards, as you catch up to the light from 2:59.
Now, in the case of the photons traveling away from each other, observing from one photon to the other will never see the other photon 'move away' from you, because the information about its position is traveling at <i>c</i>, which just happens to be your current speed. Thus, you will never observe it to go faster than <i>c</i>.
Now, one thing I've never been able to wrap my mind around are the specifics of time dilation.
Shouldn't time travel be simply illusionary? If I'm traveling at 2<i>c</i> towards another star, the Earth behind me would appear to get younger, while the star in front of me would rapidly get older. From the earth, we see stars as they were many thousands of years ago, some of which may have already exploded and died but we don't know it yet. If I travel far enough, I could observe the solar system before the earth was even formed (you know, about 5 billion lightyears), but does that mean the earth doesn't exist? No, and for every minute I went backwards relative to earth, I went a minute forward somewhere else.
This is where I don't understand the whole time dilation letting a light-speed traveler somehow age slower than others... If I returned to earth, I would accelerate FORWARD through time and thus arrive back on earth aged exactly as I should have, shouldn't I?
EDIT: I've been doing some more reading and this is pretty brain-bending stuff, but it appears that my flaw is that I'm thinking of time dilation in reference to observers, when it seems time dilation occurs because you are moving fast in relation to <i>time itself</i>. Such that were special relativity based on the frame of reference of observers, there would be no fundamental difference in one guy traveling at 0.8<i>c</i> away from a stationary guy, since velocity is meaningless without reference, it should/could appear that the stationary person is moving away from the space traveler at 0.8<i>c</i> and thus 'would' experience time dilation, but that's not the case - time dilation only occurs in the 'moving' body due to approaching the speed of light. As he approaches <i>c</i>, his movement through spacetime is effectively instantaneous, and should, I imagine, experience nothing at all, as all biological processes and even his thoughts would be slowed relative to his movement through time - at <i>c</i>, this would mean no passage of time whatsoever...
what is this i don't even
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<!--quoteo(post=1876653:date=Sep 24 2011, 01:02 AM:name=DiscoZombie)--><div class='quotetop'>QUOTE (DiscoZombie @ Sep 24 2011, 01:02 AM) <a href="index.php?act=findpost&pid=1876653"><{POST_SNAPBACK}></a></div><div class='quotemain'><!--quotec--><b>surely everyone already follows xkcd</b>, but:
<img src="http://imgs.xkcd.com/comics/neutrinos.png" border="0" class="linked-image" /><!--QuoteEnd--></div><!--QuoteEEnd-->
No, because as that strip clearly demonstrates, <b>xkcd is not, and has never been funny</b>. Randall Dumbroe is a egotistical math snob, we get it already.
Though you may find <a href="http://www.garfield.com/" target="_blank">this</a> or <a href="http://www.cad-comic.com/" target="_blank">this</a> to your liking.
Now, in the case of the photons traveling away from each other, observing from one photon to the other will never see the other photon 'move away' from you, because the information about its position is traveling at <i>c</i>, which just happens to be your current speed. Thus, you will never observe it to go faster than <i>c</i>.<!--QuoteEnd--></div><!--QuoteEEnd-->But I'm not talking about observing one from the other, I'm talking about the speed difference of one and the other. What you're saying actually supports what I said.
(also could you remove that dotted line, it ###### up my browser formatting)
Looks like you were on to something but for the wrong reason, the problem was they were not taking the measurement from Earth
<a href="http://www.fellowgeek.com/a-Einstein%E2%80%99s-Theory-Still-Safe.html" target="_blank">http://www.fellowgeek.com/a-Einstein%E2%80...Still-Safe.html</a>
Although this hasn't been fully reviewed yet either.
Now, one thing I've never been able to wrap my mind around are the specifics of time dilation.
Shouldn't time travel be simply illusionary? If I'm traveling at 2<i>c</i> towards another star, the Earth behind me would appear to get younger, while the star in front of me would rapidly get older. From the earth, we see stars as they were many thousands of years ago, some of which may have already exploded and died but we don't know it yet. If I travel far enough, I could observe the solar system before the earth was even formed (you know, about 5 billion lightyears), but does that mean the earth doesn't exist? No, and for every minute I went backwards relative to earth, I went a minute forward somewhere else.
This is where I don't understand the whole time dilation letting a light-speed traveler somehow age slower than others... If I returned to earth, I would accelerate FORWARD through time and thus arrive back on earth aged exactly as I should have, shouldn't I?
EDIT: I've been doing some more reading and this is pretty brain-bending stuff, but it appears that my flaw is that I'm thinking of time dilation in reference to observers, when it seems time dilation occurs because you are moving fast in relation to <i>time itself</i>. Such that were special relativity based on the frame of reference of observers, there would be no fundamental difference in one guy traveling at 0.8<i>c</i> away from a stationary guy, since velocity is meaningless without reference, it should/could appear that the stationary person is moving away from the space traveler at 0.8<i>c</i> and thus 'would' experience time dilation, but that's not the case - time dilation only occurs in the 'moving' body due to approaching the speed of light. As he approaches <i>c</i>, his movement through spacetime is effectively instantaneous, and should, I imagine, experience nothing at all, as all biological processes and even his thoughts would be slowed relative to his movement through time - at <i>c</i>, this would mean no passage of time whatsoever...
...<!--QuoteEnd--></div><!--QuoteEEnd-->
I've always thought of it as light conveys more information than just em waves. Say it's the signal that tells metaphysical "clocks" to tick. So the speed of light is the speed of time. It'd be like if you took a set of instructions on a PC and ran them at a different clock speed than other instructions in the program.
In any case, the only sane thing to do when confronted by this stuff is to abandon the idea of time as a concept all together. :P At least unless your Michio Kaku or Hawking or someone who can actually comprehend.
Though you may find <a href="http://www.garfield.com/" target="_blank">this</a> or <a href="http://www.cad-comic.com/" target="_blank">this</a> to your liking.<!--QuoteEnd--></div><!--QuoteEEnd-->
Ehh, I figure anyone with a brain will get most of them.
I have zero mathematics training and I still get most of them.