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Author Topic:   Existence
Stile
Member
Posts: 4295
From: Ontario, Canada
Joined: 12-02-2004


Message 546 of 1229 (620309)
06-15-2011 12:37 PM
Reply to: Message 516 by ICANT
06-14-2011 12:11 PM


The Difference Between Bullets and Light
The Speed of Bullets
1. A bullet is fired, it travels at exactly b (Where 'b' is a value for the speed of bullets in a vacuum).
2. A rocket is launched chasing the bullet, it travels at exactly 0.5b
Observation: As far as the rocket is concerned, the bullet is travelling away from it at a speed of 0.5b
The Speed of Light
1. A photon is emitted, it travels at exactly c (Where 'c' is a value for the speed of light in a vacuum).
2. A rocket is launched chasing the photon, it travels at exactly 0.5c
Observation: As far as the rocket is concerned, the photon is travelling away from it at a speed of c
I take it ICANT doesn't agree?
This is reality. It is fact. It has been tested, retested, verified and confirmed many, many times by many different scientists around the world. Disagreeing with this is like saying (as someone else already pointed out) "3 apples + 2 oranges = 5 apples".
Light does not behave as things like bullets and other mundane objects do. Repeated observations of reality show that light behaves under significantly different rules. If you ignore those rules, or think they are unnecessary for reality... you are simply wrong.
If you are okay denying reality, and simply being wrong, then no one will be able to show you the light.

This message is a reply to:
 Message 516 by ICANT, posted 06-14-2011 12:11 PM ICANT has not replied

Stile
Member
Posts: 4295
From: Ontario, Canada
Joined: 12-02-2004


Message 914 of 1229 (627302)
08-02-2011 12:26 AM
Reply to: Message 905 by ICANT
07-29-2011 4:53 PM


Another Attempt
The photon doesn't miss the target.
If the vehicle and apparatus was accelerating, you would be correct, and the photon would miss the target (towards the back of the vehicle).
If the vehicle and apparatus was deccelerating, you would be correct, and the photon would miss the target (towards the front of the vehicle).
However, the vehicle and appartus are not accelerating (either positive or negative)... therefore, the photon hits the target dead-centre.
If you were right, if the photon actually missed the target (towards the back of the vehicle), only under velocity and no acceleration/decceleration... then can you understand that this would cause the photon to actually hit the target if the vehicle was under a certain amount of decceleration??
Can you understand that this makes no sense at all?
Think of it... you're in a car, moving forward at a constant speed, you toss an apple in the air... all of a sudden the brakes slam on... and the apple doesn't slam into the windshield??? You actually catch it just fine in your hand again? Are you serious?
You're not even wrong about a complicated aspect of physics. You're wrong about the simple parts...
Light is not different from anything else in this simple aspect... it's different in the difficult areas that you're just surrounding the example with to make it seem like you're arguing a "higher level" point... but you're not... you're wrong and arguing about the simple physics point that is very basic.
It's just so simply shown to be a wrong way of thinking about the reality of physics...

This message is a reply to:
 Message 905 by ICANT, posted 07-29-2011 4:53 PM ICANT has not replied

Stile
Member
Posts: 4295
From: Ontario, Canada
Joined: 12-02-2004


(1)
Message 1167 of 1229 (632503)
09-08-2011 10:43 AM
Reply to: Message 1162 by ICANT
09-08-2011 4:35 AM


What about a balloon?
Let's try a simpler scenario to see if you can understand your error.
A) We have a car travelling on the Salt Lake Flats at a steady 100 km/h (no acceleration), it's got a sunroof. A guy inside the car has a balloon.
1. The sunroof is closed. He holds the balloon in front of his chest at arms length (above his knees). He lets go. The balloon drops as any balloon would (due to gravity) and gently hits his knees. Do you agree?
2. He opens the sunroof and holds the balloon outside the car. He lets go. The balloon gets whooshed away behind him and is left far behind. Do you agree?
B) We have a car travelling on the Salt Lake Flats at a steady 0.5c (no acceleration), it's got a sunroof. A guy inside the car has a balloon.
1. The sunroof is closed. He holds the balloon in front of his chest at arms length (above his knees). He lets go. The balloon drops as any balloon would (due to gravity) and gently hits his knees. Do you agree?
2. He opens the sunroof and holds the balloon outside the car. He lets go. The balloon gets whooshed away behind him and is left far behind, very, very quickly. Do you agree?
C) We have a car travelling in space, where there is no wind resistance or friction to consider, at a steady 100 km/h (no acceleration), it's got a sunroof. A guy inside the car has a balloon.
1. The sunroof is closed. He holds the balloon in front of his chest at arms length (above his knees). He lets go. This time, since there is no gravity where he is in space, the balloon just sits there, in front of him, exactly where he let it go... floating in mid-air. Do you agree?
2. He puts on a space-suit, opens the sunroof and holds the balloon outside the car. He lets go. This time, the balloon just sits there, directly above the car, exactly where he let it go... floating in mid-space. Travelling along with the car at exactly 100 km/h. Do you agree?
D) We have a car travelling in space, where there is no wind resistance or friction to consider, at a steady 0.5c (no acceleration), it's got a sunroof. A guy inside the car has a balloon.
1. The sunroof is closed. He holds the balloon in front of his chest at arms length (above his knees). He lets go. This time, since there is no gravity where he is in space, the balloon just sits there, in front of him, exactly where he let it go... floating in mid-air. Do you agree?
2. He puts on a space-suit, opens the sunroof and holds the balloon outside the car. He lets go. This time, the balloon just sits there, directly above the car, exactly where he let it go... floating in mid-space. Travelling along with the car at exactly 0.5c. Do you agree?
I take it, from your responses in this thread, that you do agree with all of A) and B). However, you only agree with C)1. and D)1. and not C)2. and D)2.? I think this is your error. I assure you that these sorts of behaviours have been experimentally tested and verified many, many times. All the above situations I have explained are exactly what happens in the real world. If you do not agree, (especially with C)1. where the balloon is being let go in space at 100km/h and remains floating directly over the car) you have a fundamental flaw in your understanding of physics and that basic flaw needs to be corrected before moving on to things like near-light speed travel and photon activity.
If you could clarify your disagreement with these simpler examples, I'm sure the more physically-inclined here would be better able to tune their answers to where your physics knowledge needs to be improved.
Things like friction (wind resistance, gravity..) are very common on earth and affect our "common-sense" thinking of how physics work. They tend to blur the lines between the definitions of velocity and acceleration unless we explicitly understand exactly how everything is working together.
A car on the Salt Lake Flats travelling at a constant velocity of 100km/h requires continuous force (acceleration from gas to the engine) to overcome the external forces (like wind resistance) that are restricting it. That's why the inside of the car and the outside of the car react so differently.
However, when we move to outer space, velocity and acceleration are more distinct and we can clearly see how the two are different. In space, without external forces (wind resistance, gravity...) inside the car and outside the car are exactly the same. Once you're going 100km/h, if you take your foot off the gas pedal the car will not slow down as it would on Earth (assuming that in space, the gas pedal controls fuel to the rocket boosters or something). I think you're having trouble accepting this because you're so used to thinking of things as they react on Earth. If you could clarify where you're having issues... I'm sure we could clarify our answers. The simpler the scenario is where we can find a disagreement, the simpler the explanation will be in order to find a meeting of the minds.

This message is a reply to:
 Message 1162 by ICANT, posted 09-08-2011 4:35 AM ICANT has replied

Replies to this message:
 Message 1174 by ICANT, posted 09-08-2011 12:39 PM Stile has replied

Stile
Member
Posts: 4295
From: Ontario, Canada
Joined: 12-02-2004


Message 1181 of 1229 (632548)
09-08-2011 1:11 PM
Reply to: Message 1174 by ICANT
09-08-2011 12:39 PM


Re: What about a balloon?
ICANT writes:
Hi Stile,
Long time no communication.
Yes, I've been... in and out of town.
I don't have any problem with what a balloon might or might not do.
Does that mean you agree with all the above scenarios? This will be helpful to your understanding... if you're interested in understanding. Just let me know if you have an issue with any of the balloon scenarios. I will be happy to go through things with you until we both understand what's going on, if you'd like.
A balloon is not a photon traveling at c when it exits the emitter.
You are correct. However, the portion of the photon-exiting-the-emitter scenario that you're getting wrong has nothing to do with the difference between regular objects (like balloons travelling at 100km/h) and photons . If you can understand what happens to the balloon, then you will understand what happens to the photon. This is why the balloon example is meaningful.
However, let's forget about balloons, if you'd like, and focus on the quote you keep bringing up.
ICANT writes:
Eienstein's postulate #2 says:
quote:
2. Second postulate (invariance of c)
As measured in any inertial frame of reference, light is always propagated in empty space with a definite velocity c that is independent of the state of motion of the emitting body.
I'm going to focus on the part I bolded.
Scenario 1
The car and apparatus on top is not moving at all through space.
The photon is emitted.
The photon hits the target, dead centre.
Scenario 2
The car and apparatus on top are moving at 0.5c through space.
The photon is emitted.
Stile says: The photon hits the target, dead centre.
ICANT says: The photon does not hit the target dead centre. All of a sudden the photon's propagation takes it somewhere behind dead centre.
All we've changed in the scenario is the "state of motion of the emitting body" (in Scenario 1 the emitting body is not moving and in Scenario 2 the emitting body has a motion of 0.5c through space).
But the Second postulate that you've quoted says this shouldn't change anything about the photon... the photon is propagated independent of the state of motion of the emitting body.
You keep quoting the Second postulate... but you keep demanding that the photon misses the target. It doesn't seem to add up.
My answer stays the same. My answer takes into acount that the photon's propagation is independent of the state of motion of the emitting body.
Your answer changes... and then you quote a postulate that your answer directly refutes? I don't understand your thought process.
If you are interested in understanding this level of physics, I advise you to ask questions about the balloon scenarios I described. They will be much easier to grasp and transfer that understanding to the propagation of photons.

This message is a reply to:
 Message 1174 by ICANT, posted 09-08-2011 12:39 PM ICANT has not replied

Stile
Member
Posts: 4295
From: Ontario, Canada
Joined: 12-02-2004


Message 1209 of 1229 (632657)
09-09-2011 9:14 AM
Reply to: Message 1202 by ICANT
09-08-2011 6:34 PM


Another Tidbit
One other thing to point out is that even if we do accept your error about the photon missing the target... you still have to accept time dilation... which is the very thing you were attempting to avoid.
Original Situation:
Car in space is travelling at 0.5c with photon apparatus on top. A photon is fired and hits the target dead centre.
While in space, Photons always travel at c.
Observer on car sees: Photon goes straight up and down.
Observer on Salt Lake Flats sees: By the time the photon gets to the target, the car has travelled 2 feet. So this observer sees the photon actually travel on an angle (the beginning of the saw-tooth pattern)... time must change in order for this situation to make sense.
That is time dilation.
ICANTs Situation:
Car in space is travelling at 0.5c with photon apparatus on top. A photon is fired and misses the target by 2 feet.
While in space, Photons always travel at c.
Observer on car sees: By the time the photon gets to the level of the target, the car has travelled 2 feet. The photon is now behind the emitter by two feet. I believe the angle was calculated by ICANT to be 26 degrees, or something?
Observer on Salt Lake Flats sees: Photon goes straight up and down... time must change in order for this situation to make sense.
That is time dilation... again.
As we can see, your attempt to correct what you don't want to accept doesn't really correct anything at all. All it does is change which observer sees the photon travel on an angle and which sees it go straight up and down.
Therefore... we have the exact same situation.
One observer sees the photon travel at a 90 degree angle, straight up and down.
One observer sees the photon travel at 26 degrees off where the final "up" is two-feet behind where it started... the beginning of the sawtooth pattern and this travelled angular distance is obviously larger than the straight up and down distance.
However, the photon is always travelling at c.
Therefore, either way, time must change in order for this situation to make sense.
That is time dilation... either way.
Of course, one way matches reality (the original situation) and one is incorrect (ICANTs situation)... but both display time dilation anyway!!
Wasn't the entire point of you claiming the photon misses the target to get around time dilation? All you've done is switch which observer sees the straight up-and-down and which sees the angle. The time dilation issue still exists, only reversed.

This message is a reply to:
 Message 1202 by ICANT, posted 09-08-2011 6:34 PM ICANT has replied

Replies to this message:
 Message 1212 by NoNukes, posted 09-09-2011 4:44 PM Stile has seen this message but not replied
 Message 1214 by ICANT, posted 09-10-2011 1:52 AM Stile has seen this message but not replied

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