Existence

Hi ICANT, Wrong, ICANT. I said that the car was enclosed. I then described using a rod to touch the blackboard from within the car before firing the lase. How can you touch the blackboard with a rod from inside an enclosed car unless the blackboard is also inside the car.I was about to apologize for being unclear until I re-read my proposal. I then noted this in your original response. So I definitely put the blackboard in the car, and you changed it. My error was failing to notice your change. I admit that I did not read your post carefully. But the answer to the question, where does the photon strike is unimportant. What is important is the path the photon takes, and the trajectory as measured in the car frame and the track frame.The problem with putting the blackboard on the salt flats is that we produce a thought experiment that operates in exactly the same way as the track sensor and detector thought experiment.To answer your question, yes, I believe that if the blackboard is in mounted on the ground, the photon will miss the blackboard. But I have no desire to convince you of that. None.Now that I've addressed your thought experiment, let's return to the experiment as I designed it. You say that the laser pen will operate "exactly as it does in the classroom". Well so do I. So let's analyze that result.In the car frame with the blackboard mounted inside the car, I say that the laser pen will strike the blackboard directly above the touch rod. That answer is the same whether or not the car is enclosed. In the car frame, the trajectory of the photon from emission to striking the blackboard is clearly at right angles to the direction of motion.However in the track frame, the blackboard moves up the tracks after the photon has been emitted as you yourself noted. Yet the photon must still hit the blackboard right above the touch rod. Quite obviously the photon trajectory cannot be at right angles to the direction of motion of the car in the track frame, or it could not hit the board in that spot. So, ICANT what is the angle between the motion of the car along the tracks and the trajectory of the photon?One simply question. Answer it correctly, and we can advance this discussion. I don't want to continue to discuss this without making some progress.I believe that you will refuse to address this scenario. You always become evasive whenever I request you to look at events as measured a two reference frames. Here is your chance to prove me wrong. Or tell me why the light pen in a moving car works "the same as it does in a classroom".

It is not found verbatim in what you quoted. So what? It is a fact nevertheless. It is in fact, a statement of postulate #2.As you yourself are completely aware, there are a number of completely equivalent, variant statements of postulate #2. I'm not stuck with the version of postulate #2 that you chose to provide here. Your pretense that there is no other version, when you yourself posted and linked to another one is just like you.You can find the version of postulate #2 that describes the speed of light as measured in any inertial reference frame being "c" in any physics textbook, or on wikipedia at the link you yourself provided. As I've discussed on several occasions in this thread, Einstein himself used the fact in his paper on relativity. That statement implies that an observer at rest in an inertial frame will always measure the speed of light in a vacuum to be c. If you insist on evidence, I'll provide it. But the fact is actually rather difficult to avoid. No ICANT. The car is at rest in one frame and moving at 0.5c as measured in a different frame. Neither the car nor the photon can be at rest and moving simultaneously as measured in a single frame. That's simply not possible. Actually, you cannot. You cannot do such a thing and still perform any physics or any meaningful observations. Since postulate #2 requires that photon move in a vacuum at speed c as measured in any reference frame, all information regarding the speed of objects other than the photon would have loose their meanings making it impossible to solve a physics problem. In your proposed frame, but the ground and the car would both be moving at speed c. The information that they moving at 0.5c relative to each other could not be applied in "photon frame"Going further to apply SR, then length contraction and time dilation associated with a frame moving at speed c would be infinite, meaning that distances along the direction of motion would collapse to zero, and no time would pass. Sorry ICANT, but a photon frame just does not work.But more to the point, claiming that we have a photon frame is a mere diversion. The photon will have coordinates and a speed c in both the track frame and the car frame regardless of whether there is a photon frame. We still have to apply postulate #2 to the car and track frames regardless of whether there is a photon frame. Your only purpose for bringing up a photon frame is to avoid discussing the other frames.You can bring up photon frames if you will. Expect that my response will be something like, "... but in the car frame, the photon is moving at a right angle to the direction of motion of the tracks with speed c." You of course will ignore what I say.

Nicely said, Scientist. Succinct and to the point. Quite unlike my own verbose response!

Actually ICANT, we are not at the same point. I do agree that the situations are remarkable similar. But for some reason you are now admitting that the angle between the tracks and the photon trajectory in the track frame is (due to the motion of the blackboard) different from the 90 degree angle measured in the car reference frame. The line connecting the emitting point and the point at which the photon strikes the blackboard is indeed the trajectory of the photon.What's new is that you have never admitted such a thing before.
And that Mr. ICANT, was the entire point of the experiment. To demonstrate that the photon trajectory creates different angles in the two different reference frames.I'll allow you to calculate the angle, which I predict will turn out to be a very familiar number. Make the distance from the light pen to the blackboard 10 feet (or any other distance other than zero that you find convenient) and let me confirm that the the car moves at 0.5c in the track frame of reference.I did want to point out another error in your thinking about reference frames. When I say that the car is moving at 0.5c in the track frame of reference, I don't need to additionally name an object that the motion is relative to. The car is moving at 0.5c relative to any object that is at rest in the track frame of reference.Edited by NoNukes, : No reason given.Edited by NoNukes, : Redo entire postEdited by NoNukes, : Change post completelyEdited by NoNukes, : No reason given.

Your answer is absolutely correct, and yet your answer still boggles my mind.Are you suggesting that if the laser pen and blackboard were mounted on top of the car rather than inside the car, that the photon from the laser pen would miss the blackboard.Yes, I think you do believe exactly that. You must if you also believe that the sensor on top of that pole was missed in that other experiment.Please tell me that I'm wrong about you. I must be wrong...ABE:And yet, I don't see how I can be wrong. The ridiculous tube you added to the light clock, your insistence on using an open flat car in the train experiment, your attempt to distinguish between the car frame of reference and the driver's frame inside the car. Your complete inability to rationally discuss frames of reference.Man do I feel foolish...I'm arguing about special relativity with a man who thinks physics works completely differently outdoors than indoors.Tell me, ICANT,How big an opening in the car would be needed to cause photons to start missing the blackboard. Would opening a window be enough? Opening the sun roof? Opening the rear hatch?Edited by NoNukes, : Reprise..Edited by NoNukes, : Yikes

Hi ICANT,You seem to be making a deliberate effort to ignore the consequences of postulate #2 even while asserting the postulate. You continue to ignore that very important part of postulate #2, and then are surprised when it is pointed out to you that your understanding is wrong. That definite velocity is "c" as measured in any reference frame. If the speed of light is "c" in a reference frame, that means that the speed of light is "c" relative to an observer at rest in the reference frame.Do you know how to measure the speed of light in a reference frame. You do that by using the coordinate system and clocks in the reference frame to calculate distance traveled by light. We will find that the speed of light relative to an object at rest in the reference frame is always "c" as directly required by postulate #2.Let's demonstrate that postulate #2 as you cite it requires that the speed of light in a vacuum be "c" for any inertial observer.Once we've picked one inertial reference frame, we also know that any reference frame moving at constant speed as measured using the coordinate system of that first reference frame is also an inertial reference frame. An observer at the origin of such a reference frame will measure "c" for the speed of light.Since postulate #2 says any inertial reference frame, then we can pick any observer moving at constant velocity, since any such observer will be at rest in some inertial reference frame. Therefore, any observer moving at constant speed must measure the speed of light in a vacuum to be speed "c".It's just that simple ICANT. The phrase "as measured in any inertial reference frame" inescapably means that all observers moving at constant speed will measure the speed of light to have the same value. The two phrases are equivalent, and given your admitted inability to give meaning to the phrase "as measured in any inertial reference frame" (See Message 1028) your denials are worthless.Here's you again on postulate #2. I think the exchange above sums up all of your arguments on special and general relativity. You don't understand the subject, and your arguments don't even get to the point of attacking what GR and SR predict. All you really have are denials, appeals to quacks as authority figures who for the most part have been demonstrated to be wrong, and science that you make up on the spot.

Golden One,Special relativity doubting has been always been in vogue. The physicists of Einstein's day had trouble accepting it, for various reasons, including some less than rigorous work on Einstein's part. But SR and GR have been subject to so much critical scrutiny that absolutely no credibility should be given to conspiracy theories.As a college freshman I once visited the seminary school where my dad was a faculty member and I was surprised to find that the school library had a science section with a several books on special relativity. But half of those few books were written by relativity doubters. I think that the major reason relativity is a target for creationists is because of GR and Big Bang cosmology. SR just happens to be an accessible attack point. Understanding GR well enough to attack it is generally not so easy.Anyway, the internet is replete with crackpots who deny special relativity, manned missions to the moon, and the link between smoking tobacco and lung cancer. Conservapedia has a fairly detailed SR/GR rebuttal page. If nothing else, ICANT has given us a small view into the goofy stuff that's out there.ICANT is also the only person I've ever encountered who actually tries to attack SR by refusing to accept/understand Newtonian/Galilean relativity. Truly unique among cranks.Edited by NoNukes, : No reason given.

I want to play ICANT science, too.ICANT believes an enclosed space defines reference frame, so that you can aim light at an object at rest in the enclosed frame, and the light will hit the object. However, he seems to believe that the same will not happen when the reference frame is not enclosed.So in an ICANT universe, if you were in an enclosed rail car proceeding down the tracks at 0.5 c, then you can aim a laser pen at a chalkboard exactly as if you were in a conventional high school physics classroom. But apparently, if you start taking down the sides of the rail car, at some point, light from the laser pen will veer off at at 26.5+ degree angle, landing well behind the point at which the laser is pointed.Of course, the above should apply to physical object and not just photons. After all, all objects are subject to Newton's law of inertia and inertial is what ICANT believes causes this silly behavior. So we ought to see this same behavior with bowling balls, juggling pins, among other things even in slow moving vehicles.So in universe ICANT, when the girl with kaleidoscope eyes is juggling objects on a train car moving at 100 mph, if I open one too many windows in the car thus 'exposing the objects to the earth frame of reference' the objects might well shoot to the back of the train.ICANT might complain that I'm wrong, because bowling balls can adopt the motion of the train, while photons cannot. But that complaint would not explain why the light beam in the enclosed moving car apparently did adopt the motion of the enclosed car under ICANT's science. A science which is apparently highly unreliable.

Maybe there is a need for clarification for the juggling experiment, but I was thinking we'd use a cutting torch to take down the sides of the enclosed rail car in that blackboard example. Also, as I recall, ICANT got real ornery when I called the flat car a rail car in an earlier mirror/laser thought experiment. I think I'm on pretty solid ground with the enclosed rail car bad science prediction.Of course there is also the fact that both the aether wind and existence of windows explanations would be pretty ridiculous.I found this in a previous ICANT thread regarding time and the origin of the universe.From Message 102 in the "ICANT'S position in the creation debate" topic.

Even if you could cheat in such a way, the direction to that "place" would not be north of the north pole. North is only defined on the surface of the glob.Similarly, if we are outside of space-time because we have found some new dimension along which to move, in what sense could our new found location represent "before" or "after"? None that I can see.

Hi ICANT,Serious question. Is anything anyone says about inertial reference frames ever going inform you? Have you ever drawn a graph ICANT? Do you find it necessary to stand directly over each point on your paper as you plot them? Can you plot your location on a map without viewing it from above?It is not necessary for the driver to view the coordinate system from above in order to determine what the coordinates in the driver's coordinate system actually are. If the driver (or you and I) knows the coordinates of an event, either by visual observation or calculation, then the driver or an equivalent inertial observer at rest in the frame (or you and I) can plot those coordinates on a map of the driver's reference frame. That's what Taq has done, and what you claim is impossible.I do note that you don't point to any errors in Taq's map.Your objection is completely ridiculous. We are discussing a thought experiment in which we can know everything that occurs in any reference frame we elect to consider. Your position that we are unable to calculate what happens in one particular reference frame, be it the driver's or some arbitrary reference frame of only academic interest is either completely asinine or deliberately evasive. Do you actually believe this question represents a reasonable way to avoid discussing events as plotted in the coordinate system of the driver's reference frame?Consider your own drawings.How does an observer on the tracks survive in a vacuum to draw events from the track reference frame? Can the NoNukes observer (who is in a vacuum) in your drawing actually see where that laser pen moving at 0.5c actually was when the sensor or detector was hit? Can he view the coordinates from above as you have drawn them?Yet you don't seem to have any problem drawing events in the track coordinate whenever you choose to do so. Why is that, inconsistent one? Why are vacuum and high speed no impediment to observer NoNukes? I say it is because you are only willing to discuss a single reference frame for each experiment. Discussing two frames risks you having to acknowledge time dilation due to relative motion.It is irrelevant what the driver can see. Taq's drawing represents what happens in the driver's coordinate system regardless of whether the driver can look down on the experiment. The driver can look down on Taq's paper later.I think my previous statements about relativity may not have been clear to you. What you are attempting to deny here is physics that was understood over one hundred years before Einstein by Galileo and Newton. We are not yet at the point of even applying special relativity in this experiment, because you are incapable of either understanding or admitting to understanding basic non-relativistic physics.Given the above, tell me why anyone would believe anything you say about the space-time, ICANT? You are worse than a novice. You have much baggage to overcome before you can even learn any physics, let alone pretend to lecture someone who knows the subject. None of that baggage has any relation to the Bible.

Completely wrong ICANT.There is no unbalanced force acting on objects in the car. It there were, the car or the objects in the car would be accelerating.

If you want to maintain that the photon hits where it is aimed, just as in a classroom, you need to come up with another explanation. There are no unbalanced forces acting on the photon, the car, or any other object inside the car.We know there are no unbalanced forces because neither the photon or any other objects in the car changes direction or speed at any point.The photon is emitted and travels in a straight line to the final destination. The car moves at a constant speed "c" in the track frame, the track frame being an inertial reference frame for the purposes of this thought experiment. No object with mass inside the car moves any significant distance in the car reference frame. The driver's coffee mug stays in the cup holder.Just what do you think is producing this unbalanced force, and why does this alleged force producer not act when the car is open rather than enclosed? How does it act on photons but no other objects in the car. You are familiar with the law of inertial right? You do understand that no unbalanced forces are required to allow an object to move at constant velocity?Perhaps you want to retract your prediction. Your prediction is correct, but there is no evidence of any unbalanced forces at work.Edited by NoNukes, : Make distinction between photon and other objects.

Hi ICANT,You continue to limit reference frames to what one observer can see despite the fact that you know that is not right. You did not need to describe NoNuke's surroundings. You put me outside the car near the tracks. It was only later that you started ranting about vacuums above the car. Unless you are postulating a vacuum that extends above the car but not on the sides of the car, NoNukes was in the same vacuum that exists above the car. So yeah, I'll take that space suit, if you please.First, the vacuum above the car is irrelevant. We are not discussing photons above the car, and we don't need an observer outside the car in order to discuss coordinates in the driver's reference frame. Do you yet appreciate how stupid a suggestion that is?Second, if we don't need to discuss the space suits, then pointing out that the driver is not wearing one is stupid. Just put the driver in a space suit if is necessary to answer the question. Space suits won't change the physics in anyway.Or don't use space suits. We only need the observers for a few nanoseconds. Humans can survive about 30 seconds or more in the vacuum of space. Or conduct the experiments in air. The results are the same for all practical purposes.Do you understand now why I consider the vacuum stuff to be a rabbit hole intended for avoiding the truth? A truth that you've already admitted as I pointed out in Message 1088. In fact this argument is really pretty close to being over. All that's left is debunking that unbalanced force you made up and then applying postulate #2. What the driver can see is irrelevant. We can plot the location of photons and objects in the driver's reference frame, and examine the physics of those objects even if the driver cannot see them. Is that clear yet? This concept been explained to you dozens of times. There are an infinite number of straight lines that pass through the emission point. Perhaps you can rephrase your question based on that information. We also want to make sure we are discussing an inertial frame of reference when answer the question. It is the case that Newton's laws hold in an inertial reference frame. I'm not sure that I would define an inertial reference frame in that way, but it's true nonetheless.But I'm not sure you know what a straight line is. I don't recall anyone in this thread postulating a path for a photon in an inertial reference frame that was not a straight line. Other posters just identify different straight lines than the ones you insist on.ABE:Upon further review, I noticed that the wording in your questions is very confused, and in fact the answer to your questions is no.You can do anything you want to a particle in an inertial reference frame including apply unbalanced forces to the particle. How could we do physics using a reference frame if we cannot apply forces to any particles?It is the motion of the frame that must be constant in speed and direction in order to have a inertial frame and not the motion of the particles we elect to examine.Here is a more correct statement.In an inertial frame, if there are no unbalanced forces on a particle, the particle will not accelerate. The particle will either remain at rest or continue moving in a straight line at constant speed. In a non-inertial frame, a particle with no unbalanced forces acting on it may or may not accelerate. Edited by NoNukes, : No reason given.Edited by NoNukes, : Correct ICANT regarding inertial frames.Edited by NoNukes, : No reason given.

Nope. The above is physics that you've made up.Since the photon is at all times, moving in a straight line at constant speed, no unbalanced force is required to explain its path. That's Newton's law of inertia, and not made up ICANT nonsense.What's the source of this unbalanced force ICANT? Surely it cannot be the motion of the car? Remember that the speed of the light in a vacuum is independent of the motion of the source, as measured in any inertial reference frame.I know you don't like the answer ICANT, but you cannot just make up forces that aren't there. And yes your tube was just as ridiculous. It is not necessary. For one thing, there was already a vacuum chamber around the light path of the light clock. Why wasn't that enough?Edited by NoNukes, : Address the tube