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Author Topic:   Existence
Taq
Member
Posts: 10158
Joined: 03-06-2009
Member Rating: 4.7


(1)
Message 1141 of 1229 (631163)
08-30-2011 7:10 PM
Reply to: Message 1135 by ICANT
08-30-2011 1:18 PM


Re: I'll chase the rabbit a bit.
But the blackboard moves 2 feet from the point the photon is emitted,
Why do you have such a tough time with inertial frames. The blackboard is motionless in that frame of reference.
However, the tracks are moving in the driver's frame of reference, and yet you think the light will hit the detector.
Why so dense?

This message is a reply to:
 Message 1135 by ICANT, posted 08-30-2011 1:18 PM ICANT has not replied

crashfrog
Member (Idle past 1549 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 1142 of 1229 (631198)
08-30-2011 11:29 PM
Reply to: Message 1117 by ICANT
08-30-2011 9:28 AM


Re: What ICAN'T can't do
But I did not mistake there movement to be my movement.
Because you could make observations of a third reference frame - the road and buildings around you, which you assume to be "stationary". That's an intelligence-based way to privilege a reference frame. But if you could not see those buildings and the road, you would have no way to determine if cars were driving past you, or you were driving past them, or some combination of the two. That's because there is no physics-based way to privilege a reference frame.
When two cars pass each other, it's as equally correct to say that Car A passed Car B as it is to say that Car B passed Car A. There are no privileged reference frames.
How would I be able to feel the motion of the train under me?
The train would not be moving.
You've never had the experience, so you don't know. You'll just have to take my word that the illusion is so strong, you're made to feel the "acceleration" of the train even though the train is stationary. It's roughly the same effect as you might feel in a flight simulator, or more accessibly, one of those 3D video amusement park "rides" that don't actually go anywhere.
If you've really never ridden on trains like this, or gone to an amusement park, your sheltered life is going to make it somewhat difficult to try to explain things to you since you won't have any of the obvious referents. Maybe you should stop posting here and get out more?
But the track will move less than the width of a human hair relative to the car in the amount of time the photon takes to reach the detector.
The car will move 2 feet relative to the track in the amount of time the photon takes to reach the detector.
That's just stupid. Distances are reciprocal - if A is a certain distance from B, B by definition must be the same distance from A. How could it be otherwise?
You've clearly made an incredibly stupid blunder, here. Would you like to take it back and try again?
In Taq's fantasy world but not in reality.
No, it is exactly accurate in reality, which is why relativistic physics models are so adept at explaining reality, compared to your idiosyncratic "models" which would necessarily lead to being able to determine one's absolute location in the universe by means of a flashlight, which obviously nobody is able to do.

This message is a reply to:
 Message 1117 by ICANT, posted 08-30-2011 9:28 AM ICANT has not replied

NoNukes
Inactive Member


(1)
Message 1143 of 1229 (631419)
08-31-2011 11:15 PM


Inertial reference frames ... again
After reading some confused statements and questions about inertial reference frames, I thought it might be productive to say some correct things about them rather than to wait to refute incorrect statements about them.
First, the definition
From Wikipedia,
Inertial frame of reference - Wikipedia
quote:
Within the realm of Newtonian mechanics, an inertial frame of reference, or inertial reference frame, is one in which Newton's first law of motion is valid.
http://www.physics.smu.edu/kehoe/1301S06/Ch4Relativity.pdf
quote:
Given the concept of inertia, we find it useful to talk about 'inertial reference frames' which are three-dimensional coordinate systems which travel at constant velocity. In such a frame, an object is observed to have no acceleration when no forces are acting on it.
Inertial Frame of Reference | Zona Land Education
quote:
There are several ways to describe an inertial frame. Here are a few descriptions:
An inertial frame of reference is a frame of reference with constant velocity.
An inertial frame of reference is a non-accelerating frame of reference.
An inertial frame of reference is a frame of reference in which the law of inertia holds.
An inertial frame of reference is a frame of reference in which Newton's laws of motion hold.
In an inertial frame of reference no fictitious forces arise.
Given the above definitions, it should be quite easy to recognize that a coordinate system moving at constant speed and direction, whether enclosed or unenclosed is an inertial reference frame.
Now let's see if some of the things said about inertial reference frames in this thread are correct.
ICANT writes:
The reference frame that is enclosed inside the car is a non-inertial reference frame as everything inside the car is acted upon by an unbalanced force.
The car being discussed above is moving in a straight line at constant speed 0.5c along tracks. Thus the car, enclosed or open is an inertial reference frame.
But what about the unbalanced forces acting on objects inside the car? Well in reality, there weren't any such forces. But if there were such forces, as long as the objects in the car obeyed the Newtons laws of motion, then the reference frame would still be an inertial reference frame. Since ICANT does not claiming that the objects do not obey Newton's laws, his rationale is simply wrong.
ICANT writes:
Once you remove the sides the photon will not be acted upon by an unbalanced force and therefore will go in a straight line from the point emitted from the laser pen at a 90 angle relative to the motion of the blackboard.
First, ICANT provides no mechanism for a force to appear and disappear depending on whether the sides are taken down. Instead he insists that his prediction of where the photon will go is correct, and then insists that a force must exist or fail to exist so that his prediction can be correct. That is simply nonsense.
But more importantly, the presence or absence of an unbalanced force on a photon does not qualify or disqualify a frame from being an inertial reference frame. The question to be answered is whether the photon responds to the presence or absence of an unbalanced force as required by Newton's laws of motion.

Replies to this message:
 Message 1144 by crashfrog, posted 09-01-2011 10:00 AM NoNukes has replied
 Message 1150 by ICANT, posted 09-07-2011 11:16 AM NoNukes has seen this message but not replied

crashfrog
Member (Idle past 1549 days)
Posts: 19762
From: Silver Spring, MD
Joined: 03-20-2003


Message 1144 of 1229 (631494)
09-01-2011 10:00 AM
Reply to: Message 1143 by NoNukes
08-31-2011 11:15 PM


Re: Inertial reference frames ... again
I think ICANT believes that a force is acting on a constant-velocity, moving car because it is moving; that is, ICANT has Aristotle's understanding of motion where force is necessary to maintain motion.
In other words most of ICANT's problems here come from the fact, as you've identified previously, that ICANT rejects not only relativistic physics, but Newtonian physics as well. The rest of us understand that there is no net force acting on the car because it is not accelerating.

This message is a reply to:
 Message 1143 by NoNukes, posted 08-31-2011 11:15 PM NoNukes has replied

Replies to this message:
 Message 1145 by Taq, posted 09-01-2011 11:19 AM crashfrog has not replied
 Message 1146 by NoNukes, posted 09-01-2011 2:37 PM crashfrog has not replied
 Message 1148 by ICANT, posted 09-07-2011 10:25 AM crashfrog has replied
 Message 1152 by Buzsaw, posted 09-07-2011 12:00 PM crashfrog has replied

Taq
Member
Posts: 10158
Joined: 03-06-2009
Member Rating: 4.7


(1)
Message 1145 of 1229 (631502)
09-01-2011 11:19 AM
Reply to: Message 1144 by crashfrog
09-01-2011 10:00 AM


Re: Inertial reference frames ... again
In other words most of ICANT's problems here come from the fact, as you've identified previously, that ICANT rejects not only relativistic physics, but Newtonian physics as well.
ICAN'T also rejects Galilean physics which states:
"any two observers moving at constant speed and direction with respect to one another will obtain the same results for all mechanical experiments"
So ICAN'T rejects a frames of reference as defined by Newton and invariance between reference frame as defined by Galileo. It seems that ICAN'T has not caught up to 300 year old physics.

This message is a reply to:
 Message 1144 by crashfrog, posted 09-01-2011 10:00 AM crashfrog has not replied

NoNukes
Inactive Member


(1)
Message 1146 of 1229 (631514)
09-01-2011 2:37 PM
Reply to: Message 1144 by crashfrog
09-01-2011 10:00 AM


Re: Inertial reference frames ... again
I think ICANT believes that a force is acting on a constant-velocity, moving car because it is moving; that is, ICANT has Aristotle's understanding of motion where force is necessary to maintain motion
I've been trying to figure out a consistent framework for ICANTs thinking. I don't think your proposed idea is it. ICANT did express the belief that a force was required to maintain constant velocity at one time, but didn't we beat that fallacy out of him during the space cycle discussion? ICANT did finally admit that the space cycle did not need to operate a propulsion system to continue moving through space at 0.5c.
Further, ICANT does not seem to have any problem understanding that an open system moving at 0.5c relative to the tracks is an inertial reference frame.
ICANT does not have or pretend to have a coherent scientific understanding. He simply adopts whatever allows him to deny or oppose science he does not like. He does not want to admit that a photon can travel at a 26.5 degree angle in an inertial reference frame, because that is tantamount to admitting to time dilation. As a result, it is far easier to find inconsistencies in ICANTs post that it is to find any consistent ideas, correct or otherwise.
Given that ICANT has admitted that photons cannot be accelerated beyond speed "c" in such situations, he's actually already admitted to far too much to avoid time dilation. For example in discussing the tube ICANT added to the light clock, ICANT and I had the following exchange in Message 855.
ICANT writes:
NoNukes writes:
It should be abundantly clear by now that you are being asked to draw the path of the photon including the 'dragging' you mention above. Since you've acknowledged that photons cannot be accelerated such that the speed of the photon is increased above c, you are also being asked to show that the resultant speed of the 'dragged' photon does not exceed "c".
No place have I said light can be forced to exceed "c".
If I am in my van on a oval race course and set my cruise control at 100 mph I will be traveling at 100 miles per hour and yet I will be accelerating due to the force exerted upon the car and my body will want to go toward the passenger side of the car.
ICANT here correctly describes acceleration as including changes in direction without a change in speed.
So regardless of ICANT ever agrees that an enclosed car is an inertial frame, he's already taken the position that 1) The photon must travel at some angle other 90 to hit the blackboard and 2) that the photon travels at speed "c" while doing so. Those admissions are sufficient to establish time dilation. However, ICANTs admissions are not 100 per cent correct, so I'm uncomfortable with using this line of argument other than to illustrate the problems with arguing with ICANT.
ICANT seems to have no problem with stating inconsistent things in order to avoid what appears to be immediately inevitable. For example, ICANT feels free to draw maps from an overhead perspective that include the paths of photons in the track frame of reference, but when Taq or I do the same thing for a different frame of reference, ICANT complains about observers in vacuums and events moving too fast to record without a high speed camera. See Message 1125.
Here are a couple more of ICANT's greatest hits
Example #1.
Me in Message 846
NoNukes writes:
Already answered. The photon pulse moves up and down while also moving horizontally along with the tube. The combined motion is along a diagonal.
ICANT's response from Message 847
ICANT writes:
NoNukes writes:
The combined motion is along a diagonal.
What is going at a diagonal?
Note ICANT quoting my question without any context so that he can pretend not to know what was asked.
Example #2.
ICANT writes:
I do not disagree that if the tube was clear and somehow the pulse could not escape and you could take a video of the entire trip you could see the pulse at a point that would look like it travels at an angle.
If you could slow down the trip frames to a femtosecond of movement of the pulse you could probably see the the pulse go at an angle across the .5 meter from top mirror to bottom mirror.
But that will never happen.
Hello? Why isn't this discussion over? ICANT admits and denies the truth all in the space of a few sentences. It was actually necessary to introduce yet another thought admittedly identical in principle thought experiment (train/blackboard) without any opaque tubes just to make the tiniest of advances in the discussion.
It is difficult to argue with someone who feels free to use the tactics illustrated above without expressing at least some frustration. I regret that I've allowed myself to slip a number of times during this thread. I'll try to do better.

This message is a reply to:
 Message 1144 by crashfrog, posted 09-01-2011 10:00 AM crashfrog has not replied

Replies to this message:
 Message 1147 by ICANT, posted 09-07-2011 10:06 AM NoNukes has replied

ICANT
Member (Idle past 109 days)
Posts: 6769
From: SSC
Joined: 03-12-2007


Message 1147 of 1229 (632343)
09-07-2011 10:06 AM
Reply to: Message 1146 by NoNukes
09-01-2011 2:37 PM


Re: Inertial reference frames ... again
Hi NoNukes,
NoNukes writes:
I've been trying to figure out a consistent framework for ICANTs thinking.
It would be much easier to just read what I present.
NoNukes writes:
He does not want to admit that a photon can travel at a 26.5 degree angle in an inertial reference frame,
Relative to what does the photon travel at a 26.5 angle?
I will restate what I believe for you. Pay close attention to the words I use.
If the photon is released from a laser pen traveling at a 180 angle relative to the laser pen it will go in a straight line at c until it hits something and scatters or is absorbed. Unless the direction of the photon is changed by an unbalanced force.
Einstein'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.
Source
According to postulate # 2 the light is propagated in a vacuum at c independent of the state of the motion of the emitting body.
An inertial reference frame which is under discussion says:
quote:
An inertial frame of reference is one in which the motion of a particle not subject to forces is in a straight line at constant speed.
Source
Therefore, if the car is traveling at zero relative to the tracks on the Salt Lake Flats with the laser pen mounted at a 90 angle relative to the position of the car on the tracks, if a photon is emitted from the laser pen it will travel in a straight line across the car and hit the opposite side of the car.
If we mount a detector at the spot on the car that the photon hits as long as the car is sitting still relative to the tracks the photon will hit the detector.
I think we would be in agreement so far.
But when the car is put into motion and reaches 0.5 c using the distance for the photon to travel being 4 feet if the photon travels in a straight line at c it will not hit the detector unless the photon is acted upon by an unbalanced force.
You disagree and say the photon will hit the detector.
But for the photon to hit the detector the photon must travel at a 26.5 angle relative to the direction it was traveling when it was emitted from the laser pen.
You have presented no mechanism whereby the photon can change its direction and hit the detector which has moved 2 feet in the time it took for the photon to travel 4 feet.
The laser pen is mounted at a 90 angle relative to the motion of the car.
So, what changes the direction of the photon to cause it to hit the detector?
Now if we go back to the car on the tracks that are mounted to the Salt Lake Flats with the frame on the rear of the car with the sensors and detectors and modify the laser pen to emitt a laser beam when it is trigered rather than a photon the first photon would hit the detector and there would be a solid laser beam hitting the sensors and detectors until the laser pen is turned off.
I don't think you will disagree with this as you can produce such an experiment by pointing your laser pen at the ceiling on one side of the room holding the on button down and moving your hand where the beam makes a solid line on the ceiling in any direction you point the laser pen.
So the only thing we disagree about is the direction the photon will travel when emitted from the laser pen.
I believe the photon will travel in a straight line in the direction it is emitted traveling in unless that direction is changed by an unbalanced force.
I think that is in agreement with postulate #2 and the definition of an inertial frame.
The photon is traveling at c independent of the emitter.
The photon is traveling in a straight line in the direction emitted.
Your claim is that the photon is traveling at a 26.5 angle relative to the direction it was traveling in when it was emitted from the laser pen.
What causes that change in direction of travel?
God Bless,

"John 5:39 (KJS) Search the scriptures; for in them ye think ye have eternal life: and they are they which testify of me."

This message is a reply to:
 Message 1146 by NoNukes, posted 09-01-2011 2:37 PM NoNukes has replied

Replies to this message:
 Message 1149 by Son, posted 09-07-2011 11:00 AM ICANT has replied
 Message 1155 by NoNukes, posted 09-07-2011 1:15 PM ICANT has replied
 Message 1157 by Taq, posted 09-07-2011 2:27 PM ICANT has not replied

ICANT
Member (Idle past 109 days)
Posts: 6769
From: SSC
Joined: 03-12-2007


Message 1148 of 1229 (632346)
09-07-2011 10:25 AM
Reply to: Message 1144 by crashfrog
09-01-2011 10:00 AM


Re: Inertial reference frames ... again
Hi crash,
crashfrog writes:
I think ICANT believes that a force is acting on a constant-velocity, moving car because it is moving; that is, ICANT has Aristotle's understanding of motion where force is necessary to maintain motion.
The laser pen is not mounted at a 180 angle relative to the motion of the car.
The laser pen is mounted at a 90 angle relative to the motion of the car.
The photon emitted from the laser pen will travel at c across the car to the oposite side.
If the car is traveling at a constant speed of 0.5 c the car will move 2 feet in the time it takes the photon to travel 4 feet from the laser pen to the oposite side of the car and hit a detector.
If the detector is mounted where the photon will strike the detector when the car is moving zero relative to the tracks on the Salt Lake Flats, it will miss the detector when the car is traveling at 0.5 c relative to the tracks on the Salt Lake Flats unless the photon is acted upon by an unbalanced force.
The photon is not traveling in the same direction as the car is traveling. No unbalanced force can be added to the photon as per the definition of postulate #2.
The photon is traveling horozontal to the travel of the car in a straight line and to hit a target that has moved 2 feet from the time the photon is emitted requires an unbalanced force be applied to accomplish this feat.
Unless the laser pen is mounted at a 26.5 angle relative to the motion of the car to cause it to hit the target 2 feet from where it was when the photon was emitted.
The problem is the laser pen is mounted at a 90 angle relative to the motion of the car.
God Bless,

"John 5:39 (KJS) Search the scriptures; for in them ye think ye have eternal life: and they are they which testify of me."

This message is a reply to:
 Message 1144 by crashfrog, posted 09-01-2011 10:00 AM crashfrog has replied

Replies to this message:
 Message 1159 by crashfrog, posted 09-07-2011 4:58 PM ICANT has not replied

Son
Member (Idle past 3912 days)
Posts: 346
From: France,Paris
Joined: 03-11-2009


Message 1149 of 1229 (632354)
09-07-2011 11:00 AM
Reply to: Message 1147 by ICANT
09-07-2011 10:06 AM


Re: Inertial reference frames ... again
I thought that you have spent the days during which you were absent to learn some basic physics, but it doesn't seem to be the case...
ICANNT writes:
Your claim is that the photon is traveling at a 26.5 angle relative to the direction it was traveling in when it was emitted from the laser pen.
Our claims is that the photon is traveling at a 90 angle relative to the direction the car is traveling in the CAR's frame of reference. You still refuse to address the point that for every description of travel, you NEED to say which frame you use and why.

This message is a reply to:
 Message 1147 by ICANT, posted 09-07-2011 10:06 AM ICANT has replied

Replies to this message:
 Message 1151 by ICANT, posted 09-07-2011 11:31 AM Son has replied

ICANT
Member (Idle past 109 days)
Posts: 6769
From: SSC
Joined: 03-12-2007


Message 1150 of 1229 (632359)
09-07-2011 11:16 AM
Reply to: Message 1143 by NoNukes
08-31-2011 11:15 PM


Re: Inertial reference frames ... again
Hi NoNukes,
NoNukes writes:
The car being discussed above is moving in a straight line at constant speed 0.5c along tracks. Thus the car, enclosed or open is an inertial reference frame.
But the photon under discussion is not traveling in the same direction that the car is traveling. In fact it is traveling at a 90 angle relative to the travel of the car.
So what makes the photon hit the detector which has moved 2 feet during the time it takes for the photon to travel the 4 feet across the car?
NoNukes writes:
Since ICANT does not claiming that the objects do not obey Newton's laws, his rationale is simply wrong.
But I do claim that the photon does not obey Newton's laws and the definition of an inertial frame if it hits the detector as you claim. If it does obey those laws it will not hit the detector.
NoNukes writes:
First, ICANT provides no mechanism for a force to appear and disappear depending on whether the sides are taken down. Instead he insists that his prediction of where the photon will go is correct, and then insists that a force must exist or fail to exist so that his prediction can be correct. That is simply nonsense.
Your conclusions is what is nonsense.
I am simply saying if the laws of Newton and the definition of an inertial frame and Einstein's postulate #2 is correct the photon which is emitted from a laser pen which is mounted at a 90 angle relative to the 0.5 c motion of the car can not hit a detector that is mounted at a 180 angle relative to the laser pen after the detector has moved 2 feet unless an unbalanced force is applied to the photon.
If no unbalanced force is applied to the photon it will miss the detector whether in an enclosed or open car.
NoNukes writes:
But more importantly, the presence or absence of an unbalanced force on a photon does not qualify or disqualify a frame from being an inertial reference frame.
From your source you quoted.
quote:
Inertia: An object moves at constant velocity unless acted upon by an external force.
This sentence immediately preceeds your quote.
NoNukes writes:
http://www.physics.smu.edu/kehoe/1301S06/Ch4Relativity.pdf
quote:
Given the concept of inertia, we find it useful to talk about 'inertial reference frames' which are three-dimensional coordinate systems which travel at constant velocity. In such a frame, an object is observed to have no acceleration when no forces are acting on it.
According to that if the photon is acted upon by an external force the reference frame in which the photon is, is not an inertial reference frame.
So unless an unbalanced force is placed upon the direction the photon is traveling in the enclosed car what causes the photon to travel at a 26.5 angle relative to the point and direction the photon is traveling at when emitted?
NoNukes writes:
The question to be answered is whether the photon responds to the presence or absence of an unbalanced force as required by Newton's laws of motion.
What else do you apply to cause the photon to travel at a 26.5 angle relative to the point and direction the photon is traveling at when emitted as per your assertion?
If an unbalanced force does not change the direction of the photon what does cause it to hit the detector 2 feet from where the laser pen was pointed at the moment the photon was emitted?
God Bless,

"John 5:39 (KJS) Search the scriptures; for in them ye think ye have eternal life: and they are they which testify of me."

This message is a reply to:
 Message 1143 by NoNukes, posted 08-31-2011 11:15 PM NoNukes has seen this message but not replied

ICANT
Member (Idle past 109 days)
Posts: 6769
From: SSC
Joined: 03-12-2007


Message 1151 of 1229 (632363)
09-07-2011 11:31 AM
Reply to: Message 1149 by Son
09-07-2011 11:00 AM


Re: Inertial reference frames ... again
Hi Son,
Son writes:
Our claims is that the photon is traveling at a 90 angle relative to the direction the car is traveling in the CAR's frame of reference. You still refuse to address the point that for every description of travel, you NEED to say which frame you use and why.
So you are in agreement with me that the photon travels at a 90 angle relative to the motion of the car.
Wouldn't that be true in every inertial reference frame?
Is that an inertial frame of reference where the photon can only go in the direction at c relative to the point it was emitted, the photon that is emitted will travel in a straight line from the point emitted and hit the side of the car 2 feet from where the laser pen was pointed at the moment the photon was emitted unless an unbalanced force is applied to the photon to change it's direction.
God Bless,

"John 5:39 (KJS) Search the scriptures; for in them ye think ye have eternal life: and they are they which testify of me."

This message is a reply to:
 Message 1149 by Son, posted 09-07-2011 11:00 AM Son has replied

Replies to this message:
 Message 1154 by Son, posted 09-07-2011 12:22 PM ICANT has not replied
 Message 1161 by Boof, posted 09-07-2011 8:07 PM ICANT has replied

Buzsaw
Inactive Member


Message 1152 of 1229 (632364)
09-07-2011 12:00 PM
Reply to: Message 1144 by crashfrog
09-01-2011 10:00 AM


Re: Inertial reference frames ... again
Crashfrog writes:
The rest of us understand that there is no net force acting on the car because it is not accelerating.
How does that size up to 3LoT, in that there is no perpetual machine? Not having followed the thread, perhaps that has been addressed.
--------------------------------------------------------------------------------

BUZSAW B 4 U 2 C Y BUZ SAW.
The Immeasurable Present Eternally Extends the Infinite Past And Infinitely Consumes The Eternal Future.

This message is a reply to:
 Message 1144 by crashfrog, posted 09-01-2011 10:00 AM crashfrog has replied

Replies to this message:
 Message 1153 by Panda, posted 09-07-2011 12:10 PM Buzsaw has not replied
 Message 1156 by DrJones*, posted 09-07-2011 1:34 PM Buzsaw has not replied
 Message 1160 by crashfrog, posted 09-07-2011 5:03 PM Buzsaw has not replied

Panda
Member (Idle past 3795 days)
Posts: 2688
From: UK
Joined: 10-04-2010


(1)
Message 1153 of 1229 (632365)
09-07-2011 12:10 PM
Reply to: Message 1152 by Buzsaw
09-07-2011 12:00 PM


Re: Inertial reference frames ... again
Buzsaw writes:
How does that size up to 3LoT, in that there is no perpetual machine?
quote:
Newton's First law: The velocity of a body remains constant unless the body is acted upon by an external force.
Edited by Panda, : No reason given.

Always remember: QUIDQUID LATINE DICTUM SIT ALTUM VIDITUR
Science flies you into space; religion flies you into buildings.

This message is a reply to:
 Message 1152 by Buzsaw, posted 09-07-2011 12:00 PM Buzsaw has not replied

Son
Member (Idle past 3912 days)
Posts: 346
From: France,Paris
Joined: 03-11-2009


(1)
Message 1154 of 1229 (632366)
09-07-2011 12:22 PM
Reply to: Message 1151 by ICANT
09-07-2011 11:31 AM


Re: Inertial reference frames ... again
ICANT writes:
So you are in agreement with me that the photon travels at a 90 angle relative to the motion of the car.
Wouldn't that be true in every inertial reference frame?
How could that be true???
In the car's frame of reference, if the photon hits where you think it will, the path of the photon will make a 26.5 angle whereas it would make a
90 angle relative to the direction the car is traveling in the Salt Flat Lake's of reference. That's because in this case, your photon would go backward in the car's frame of reference.
As I said, please go learn what an inertial reference frame is. There's no way you would write such idiocies if you knew what it meant.

This message is a reply to:
 Message 1151 by ICANT, posted 09-07-2011 11:31 AM ICANT has not replied

NoNukes
Inactive Member


Message 1155 of 1229 (632372)
09-07-2011 1:15 PM
Reply to: Message 1147 by ICANT
09-07-2011 10:06 AM


Re: Inertial reference frames ... again
Hi ICANT,
There are answers to questions from more than one of your posts here.
ICANT writes:
NoNukes writes:
I've been trying to figure out a consistent framework for ICANTs thinking.
It would be much easier to just read what I present.
Easier, perhaps, but that's not how I roll. I want to understand the 'science' underlying your answers. I've already concluded that your explanations do not agree with reality as I understand it. But beyond that your explanations are not consistent.
But when the car is put into motion and reaches 0.5 c using the distance for the photon to travel being 4 feet if the photon travels in a straight line at c it will not hit the detector unless the photon is acted upon by an unbalanced force.
Yet this unbalanced force is without explanation. It appears and disappears as needed for the sole purpose of making your prediction of where the photon hits come true. This force inexplicably knows whether the car is open or enclosed and selectively applies or does not apply itself to the photon.
ICANT writes:
An inertial reference frame which is under discussion says:
quote:
An inertial frame of reference is one in which the motion of a particle not subject to forces is in a straight line at constant speed.
You are badly misreading the correct statement above. Yes it is true that in an inertial reference frame, a particle not subject to forces moves in a straight line at constant speed (or remains at rest). But what happens in an inertial reference frame when a particle is subject to an unbalanced force? Well the above statement is silent about that.
The answer is that the particle will obey Newton's laws. In particular, F=ma would apply.
ICANT writes:
quote:
Given the concept of inertia, we find it useful to talk about 'inertial reference frames' which are three-dimensional coordinate systems which travel at constant velocity. In such a frame, an object is observed to have no acceleration when no forces are acting on it.
According to that if the photon is acted upon by an external force the reference frame in which the photon is, is not an inertial reference frame.
Wrong again, ICANT. You have again misunderstood the exact same physics. The sentence describes how a particle acts in an inertial reference frame WHEN no forces are acting on the particle. In such a case, the particle does not accelerate. The sentence says nothing about what happens when a force IS acting on the particle. But we do have other definitions/descriptions that do apply in that situation, don't we ICANT?
Notice that the first part of the quote tells us that reference frames traveling at constant velocity (for example rail cars with their sides taken down) are inertial reference frames. Well isn't that awful inconvenient for you?
The definitions/descriptions I provided in that prior post all apply to every inertial reference frame. A coordinate system moving at a constant velocity (like an open car) is an inertial reference frame. If a reference frame (the car) is not accelerating, then a particle not subject to a net force will either move at constant velocity or remain at rest. If a force is acting on the particle in an inertial reference frame, then a different one of Newton's law's applies, namely F=ma.
Frankly, your attempts to lecture people who understand physics on inertial reference frames, when you don't understand how to use reference frames of any kind is pretty amusing. The sac involved in attempting to apply postulate 2 after admitting that you don't understand a substantial part of it ("As measured in any inertial reference frame") is even admirable in a way. But it would be the sheerest of coincidences if anything you said about an inertial coordinate system were correct. So far you are batting well below the Mendoza line.
I believe the photon will travel in a straight line in the direction it is emitted traveling in unless that direction is changed by an unbalanced force.
First, that statement has nothing to do with postulate #2, as you yourself have previously admitted. You indicated that the statement was based on the law of inertial and postulate #1. That's pretty much right. Let me know if you need a pointer to your previous message.
Postulate #2 says that the speed of light in a vacuum having the value "c" as measured in any inertial reference frame. Postulate #2 would allow light to change direction by bouncing off a mirror without having a force applied.
Second, I do not describe the photon changing direction after being emitted. Nobody here has done that.
What I do say is that as measured in different frames, the angle between the tracks and the direction along which the photon travels (I will call this angle the photon's trajectory angle) will be different in different reference frames.
As measured in the car frame of reference, the photon trajectory angle is 90. Since the blackboard and laser pen are stationary in the car reference frame, that 90 trajectory angle means that the photon hits the blackboard.
On the other hand, the trajectory angle for the photon is different as measured in the track frame of reference. The reason for the difference is that the separation between the origin of the track reference frame and the origin of the car reference frame increases with time at a rate of 0.5c. If we ignore special relativity, we will calculate the trajectory angle as measured in the track frame of reference to be 26.5. If we apply postulate #2 of special relativity, we will calculate a trajectory angle of 30. These trajectory angles are consistent with the fact that the blackboard does indeed move away from the point at which the photon was emitted when measured in the track frame of reference.
When we analyze the results one reference frame at a time, the results comply with postulate #1 for each frame. As measured in either one of the two frames under discussion, the photon travels at a constant speed, in a constant direction. That's all that's required to satisfy newton's laws of inertial, so no force is required to explain the results in either frame.
ICANT writes:
What causes that change in direction of travel?
There is no change in direction of travel. There are only different measurements in different reference frames. The photon trajectory angle, the light pen aiming angle, the velocity of the blackboard, and the velocity of the tracks are all parameters that have different values as measured in the two reference frames under discussion. If you can understand at least that, then you can see where your questions are not working.
So you are in agreement with me that the photon travels at a 90 angle relative to the motion of the car.
Wouldn't that be true in every inertial reference frame?
No ICANT. It would not be true in every inertial reference frame which is why everyone except you specifies the reference frame for the measurement whenever more than one reference frame is involved. Further, I have demonstrated that this statement is not correct using diagrams and mathematics. I also provided a link to a video in which a physicist discussed coordinate transforms between inertial reference frames to confirm my position. Yet you continue to insist on a wrong answer. It's well past time that you supported your belief with a reference.
Trajectory angles for photons and other objects traveling at finite velocities are not consistent between different inertial reference frames when the origins of the coordinate systems are in relative motion. Neither postulate #1 not postulate #2 require any such thing either for massless photons or for objects with mass.
Your position is that one of Einstein's postulates used to generate special relativity is actually inconsistent with SR. I'm open to having you demonstrate that, but you aren't going to make a successful argument without knowing even what an inertial reference frame is. And you don't.
I think it is about summary time.
Edited by NoNukes, : Grammar, and spell Mendoza with a Z.

This message is a reply to:
 Message 1147 by ICANT, posted 09-07-2011 10:06 AM ICANT has replied

Replies to this message:
 Message 1162 by ICANT, posted 09-08-2011 4:35 AM NoNukes has replied

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