time - Tilted Forum Project Discussion Community

AppleSauceMcGee · 07-07-2003, 09:20 PM

ever notice that when u look at a clock the second hand or number seems to be frozen for a long time when u first look at it??? its not really anything to do with philosophy but i did not know where to post it.... maybe times stops... or ever knotice how a group of people can percieve time to go by "fast" or "slow"..... often people that have not done the same activities will say "man today was slow"

papermachesatan · 07-07-2003, 09:41 PM

That's entirely a matter of perspective.

urgodhere · 07-07-2003, 09:54 PM

i agree with the papermachesatan...its all a matter of perspective. Also you might want to look int the Theory of Relativity. That might answer some of the thoughts that are running atound in your head.

guypunkr · 07-07-2003, 09:57 PM

Is there a simple way to explain the Theory of Relativity? I've never found anyone that could put it in "Lame Man's terms." (I've also heard that only about a dozen people on earth truly understand the theory completely.)

oxymorphone · 07-07-2003, 11:49 PM

Einstein's Special Theory of relativity is easily explained, you just have to accept that time slows down as you get closer to moving at the speed of light. The General Theory of Relativity is much more complicated and I've never seen it explained without a bunch of math.

Even more relevant though is the Theory of Classroom Clocks which states that time slows down as you approach graduation.

CSflim · 07-11-2003, 11:43 AM

The speed of light is absolutely constant. In effect time will "change" in order to accomodate this.

You start off driving down a raod at 10mph. You look out the window, and see the scenery flying by. To you, you could imagine that YOU are infact stationary, and that it is everything else, which is moving at 10mph.

Now a second car, coming up behind you is travelling at 30mph. You watch it as it passes you. From your perspective, the car appears to pass you at 20mph. This is relative velocity.

Now repeat the experiment. This time in space. Two space ships are side by side. Space ship A takes off at a quarter the speed of light. Very fast indeed! After a very brief pause, Spaceship B switches on his headllamps. The beams off light shoot off after Spaceship A at the speed of light, and eventually catch up and overtake spaceship A.

Now suppose you are in Spaceship A, lookign out your window. At what speed will the light APEAR to pass you at? Well, appling classical mechanics, it would appear that you would see the light pass you at 3/4 the speed of light. Right?

Wrong! Like I said, the speed of light is absolutely constant. You will see the light beam pass you at the full speed of light. How is this possible?

Well, you are looking out your window at or world speeded up. Or, put another way, in your spaceship, time is running slower than for the rest of the world! You could, in a way, travel into the future! Since you are seeing the outside world age more quickly, if you timed yourself and waited say a year, and returned to earth, you would find that you had been gone for longer than a year! Travelled into the future!

This traveling into the future IS NOT just some mathematical conjecture. It is an observable fact! Indeed we have time travellers living among us today! No I'm not from some weird cult: Many astronaughts are fractions of a second younger than they should be!
Also artificial satelites of earth must have their clocks periodically re-callibrated, as the accuracy of their measurements requires extrememly accurate time measurements... this is componded by the fact that they lose minute fractions of a second every year through "time travel".

Now go back to our spaceships experiment. As you move faster and faster, you experience time slower and slower. If you were to extrapoate these results, you could come to some interesting conclusions.
At the speed of light, your experience of time would stop! Time would pass at a rate of...0!
Looking out your window you would see everything happen at once! From your position, there is no time!
Now what would happen if we were to go even faster than the speed of light? Well, again extrapolating our results we would find that our experience of time would become negative. We would travel BACKWARDS in time!

As you can see, these results show why it would be impossible for us to accelerate to the speed of light.

Schwan · 07-11-2003, 11:48 AM

Quote:

Originally posted by CSflim
As you can see, these results show why it would be impossible for us to accelerate to the speed of light.

What if we built this large rotating mechanism with an infinitely long outstreching arm and sit at the end of it and...

Oh, never mind.

debaser · 07-11-2003, 02:46 PM

Quote:

Originally posted by CSflim

As you can see, these results show why it would be impossible for us to accelerate to the speed of light.

Actually the thing that prevents us from achieving the speed of light is the strange fact that as an object increases velocity, it gains mass. This is described by the Lorentz Invariant. As an object approaches the speed of light it will also aproach infinite mass. To accelerate such an object would take, you guessed it, infinite energy. Thus, no light speed for you.

Schwan · 07-11-2003, 02:52 PM

Quote:

Originally posted by debaser
Actually the thing that prevents us from achieving the speed of light is the strange fact that as an object increases velocity, it gains mass. This is described by the Lorentz Invariant. As an object approaches the speed of light it will also aproach infinite mass. To accelerate such an object would take, you guessed it, infinite energy. Thus, no light speed for you.

Well, okay, but then, how does light itslef... oh, wait, it doesn't have any mass... but you just said that to achieve the speed of light... AAAAAAAAARGH

cheerios · 07-11-2003, 03:24 PM

no, light does TOO have mass! remember light is both a particle and a wave, and particles have mass.

Schwan · 07-11-2003, 03:31 PM

So I might just as well ask. How does it achieve infinte mass and energy, then?

CSflim · 07-11-2003, 04:06 PM

Quote:

Originally posted by debaser
Actually the thing that prevents us from achieving the speed of light is the strange fact that as an object increases velocity, it gains mass. This is described by the Lorentz Invariant. As an object approaches the speed of light it will also aproach infinite mass. To accelerate such an object would take, you guessed it, infinite energy. Thus, no light speed for you.

In my defense I was trying to explain it in as simple as words as possible. But yes, you are correct.

debaser · 07-11-2003, 04:10 PM

Quote:

Originally posted by cheerios
no, light does TOO have mass! remember light is both a particle and a wave, and particles have mass.

Actually it behaves like both a particle and a wave, whatever thats worth to you...

CSflim · 07-11-2003, 04:11 PM

Quote:

Originally posted by cheerios
no, light does TOO have mass! remember light is both a particle and a wave, and particles have mass.

Light doesn't have a mass. Not all particles have mass. Many "fundamental" particles are volumeless "points" and are massless.

That being said, light does have energy, and as we know, light and mass are equivalent, but not the same. Mass is a particular (structured) form of energy. So in a way you could say that light has a mass, but not as we think of it. So it really means that it depends on what type of mass you are talking about

http://www.math.ucr.edu/home/baez/ph...ight_mass.html

CSflim · 07-11-2003, 04:53 PM

Quote:

Originally posted by AppleSauceMcGee
ever notice that when u look at a clock the second hand or number seems to be frozen for a long time when u first look at it???

Get yourself a Rolex!

cheerios · 07-11-2003, 05:53 PM

apologies CS, partof it is is i'm too lazy to find my physics book and look this up properly, and it's been like a year an a half since I've had to think about this stuff.

that said, light does too have mass. i distinctly remember this. if you'll excuse me while i rummage through boxes of books, I'll check for ya.

debaser · 07-11-2003, 07:11 PM

Light does not have mass per se. It behaves as a particle or a wave, depending on how and when you measure it. A photon has energy which is in many ways equal to mass (remember an objects energy equals its mass times the speed of light squared), but it does not have actual mass, as it would then be impossible for it move as fast as it does. As a particle it displays many of the behaviors of other massive particles, such as being effected by gravity, but at the same time it's behavior as a wave dissallows it from having mass. Confusing, no?

07-07-2003, 09:20 PM	#1 (permalink)
AppleSauceMcGee Tilted Location: universe	time ever notice that when u look at a clock the second hand or number seems to be frozen for a long time when u first look at it??? its not really anything to do with philosophy but i did not know where to post it.... maybe times stops... or ever knotice how a group of people can percieve time to go by "fast" or "slow"..... often people that have not done the same activities will say "man today was slow" __________________ "The Church says the Earth is Flat, But I know that it is Round, For I have seen the Shadow on the Moon. And I Have more faith in a shadow Than in the Church." - Ferdinand Magellan

07-11-2003, 11:43 AM	#6 (permalink)
CSflim Sky Piercer Location: Ireland	The speed of light is absolutely constant. In effect time will "change" in order to accomodate this. You start off driving down a raod at 10mph. You look out the window, and see the scenery flying by. To you, you could imagine that YOU are infact stationary, and that it is everything else, which is moving at 10mph. Now a second car, coming up behind you is travelling at 30mph. You watch it as it passes you. From your perspective, the car appears to pass you at 20mph. This is relative velocity. Now repeat the experiment. This time in space. Two space ships are side by side. Space ship A takes off at a quarter the speed of light. Very fast indeed! After a very brief pause, Spaceship B switches on his headllamps. The beams off light shoot off after Spaceship A at the speed of light, and eventually catch up and overtake spaceship A. Now suppose you are in Spaceship A, lookign out your window. At what speed will the light APEAR to pass you at? Well, appling classical mechanics, it would appear that you would see the light pass you at 3/4 the speed of light. Right? Wrong! Like I said, the speed of light is absolutely constant. You will see the light beam pass you at the full speed of light. How is this possible? Well, you are looking out your window at or world speeded up. Or, put another way, in your spaceship, time is running slower than for the rest of the world! You could, in a way, travel into the future! Since you are seeing the outside world age more quickly, if you timed yourself and waited say a year, and returned to earth, you would find that you had been gone for longer than a year! Travelled into the future! This traveling into the future IS NOT just some mathematical conjecture. It is an observable fact! Indeed we have time travellers living among us today! No I'm not from some weird cult: Many astronaughts are fractions of a second younger than they should be! Also artificial satelites of earth must have their clocks periodically re-callibrated, as the accuracy of their measurements requires extrememly accurate time measurements... this is componded by the fact that they lose minute fractions of a second every year through "time travel". Now go back to our spaceships experiment. As you move faster and faster, you experience time slower and slower. If you were to extrapoate these results, you could come to some interesting conclusions. At the speed of light, your experience of time would stop! Time would pass at a rate of...0! Looking out your window you would see everything happen at once! From your position, there is no time! Now what would happen if we were to go even faster than the speed of light? Well, again extrapolating our results we would find that our experience of time would become negative. We would travel BACKWARDS in time! As you can see, these results show why it would be impossible for us to accelerate to the speed of light. __________________

07-11-2003, 07:11 PM	#17 (permalink)
debaser Sir, I have a plan... Location: 38S NC20943324	Light does not have mass per se. It behaves as a particle or a wave, depending on how and when you measure it. A photon has energy which is in many ways equal to mass (remember an objects energy equals its mass times the speed of light squared), but it does not have actual mass, as it would then be impossible for it move as fast as it does. As a particle it displays many of the behaviors of other massive particles, such as being effected by gravity, but at the same time it's behavior as a wave dissallows it from having mass. Confusing, no? __________________ Fortunato became immured to the sound of the trowel after a while.

07-07-2003, 09:41 PM	#2 (permalink)
papermachesatan Psycho Location: Texas	That's entirely a matter of perspective.

07-07-2003, 09:54 PM	#3 (permalink)
urgodhere Banned Location: Limbo	i agree with the papermachesatan...its all a matter of perspective. Also you might want to look int the Theory of Relativity. That might answer some of the thoughts that are running atound in your head.

07-07-2003, 09:57 PM	#4 (permalink)
guypunkr Loser Location: Newport News, VA	Is there a simple way to explain the Theory of Relativity? I've never found anyone that could put it in "Lame Man's terms." (I've also heard that only about a dozen people on earth truly understand the theory completely.)

07-07-2003, 11:49 PM	#5 (permalink)
oxymorphone Upright Location: under a rock	Einstein's Special Theory of relativity is easily explained, you just have to accept that time slows down as you get closer to moving at the speed of light. The General Theory of Relativity is much more complicated and I've never seen it explained without a bunch of math. Even more relevant though is the Theory of Classroom Clocks which states that time slows down as you approach graduation.

07-11-2003, 03:24 PM	#10 (permalink)
cheerios Banned Location: 'bout 2 feet from my iMac	no, light does TOO have mass! remember light is both a particle and a wave, and particles have mass.

07-11-2003, 03:31 PM	#11 (permalink)
Schwan A boy and his dog Location: EU!	So I might just as well ask. How does it achieve infinte mass and energy, then?

07-11-2003, 05:53 PM	#16 (permalink)
cheerios Banned Location: 'bout 2 feet from my iMac	apologies CS, partof it is is i'm too lazy to find my physics book and look this up properly, and it's been like a year an a half since I've had to think about this stuff. that said, light does too have mass. i distinctly remember this. if you'll excuse me while i rummage through boxes of books, I'll check for ya.