Wonderful!
in [Physics]
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From: PD on 22 Dec 2009 09:38 On Dec 21, 6:40 pm, mpc755 <mpc...(a)gmail.com> wrote: > On Dec 21, 3:58 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Dec 21, 1:44 pm, mpc755 <mpc...(a)gmail.com> wrote: > > > > On Dec 21, 12:14 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Dec 17, 12:05 pm, mpc755 <mpc...(a)gmail.com> wrote: > > > > > > On Dec 17, 1:03 pm, "papar...(a)gmail.com" <papar...(a)gmail.com> wrote: > > > > > > > On 17 dic, 14:59, mpc755 <mpc...(a)gmail.com> wrote: > > > > > > > > On Dec 17, 12:54 pm, "papar...(a)gmail.com" <papar...(a)gmail.com> wrote: > > > > > > > > The water is at rest relative to the embankment. There is a single > > > > > > > LIGHTNING STRIKE in the water at A/A' and a single LIGHTNING STRIKE in > > > > > > > the water at B/B'. Where does the Observer at M' measure to in order > > > > > > > to determine how far the LIGHT travels? Does the Observer at M' > > > > > > > measure to A' and B', or does the Observer at M' measure to A and B in > > > > > > > order to determine how far the LIGHT travels to M'? > > > > > > > Observer M' is passing by the location of observer M, at time t0. M' > > > > > > is moving at a speed v, relative to observer M, on the direction of x. > > > > > > All this is happening in deep space, without an gravitational mass > > > > > > (including water). Later, at time t1, observer M sees TWO simultaneous > > > > > > light signals A and B arriving from opposite directions along x.. > > > > > > > Question: a) Since observer M', in the interval of time (t1-t0) has > > > > > > already moved towards the source of the light signal B, did he observe > > > > > > the light signal coming from B before observer M, or did he not? > > > > > > b) Since at time t1, the ligth signal coming from point A is at the > > > > > > location of observer M, is it true that the light signal coming from > > > > > > point A has some travel to do to arrive to the location of observer > > > > > > M', or is it not true? > > > > > > c) From (a) and (b) is it true that observer M' will declare that he > > > > > > received two non simultaneous light signals (first the ligt signal > > > > > > from point B, later the light signal from point A), or is it not true? > > > > > > > Miguel Rios > > > > > > The water is at rest relative to the embankment. There is a single > > > > > LIGHTNING STRIKE in the water at A/A' and a single LIGHTNING STRIKE in > > > > > the water at B/B'. > > > > > I'm glad you're at least talking about two strikes, not four. That's > > > > at least somewhat close to Einstein's gedanken. > > > > > > Where does the Observer at M' measure to in order > > > > > to determine how far the LIGHT travels? Does the Observer at M' > > > > > measure to A' and B', or does the Observer at M' measure to A and B in > > > > > order to determine how far the LIGHT travels to M'? > > > > > M' measures to A' (because that's where the lightning struck) and to > > > > B' (because that's where the lightning struck). > > > > And the Observer at M' would be incorrect. The light from the > > > lightning strike at A/A' and B/B' travels with respect to the water > > > which is at rest with respect to the embankment. The light from the > > > lightning strikes DOES NOT travel from A' and B' to M', the light from > > > the lightning strikes travels from A and B to M'. > > > At the time of the lightning strike, A and A' are at the same > > location. Then the light leaves that common spot before A and A' > > separate. Therefore to say that the light comes from A and not A', > > when A and A' were at the SAME PLACE at the moment of the strike, is > > not just stupid, it is spectacularly stupid. > > The water is at rest with respect to the embankment. A pebble is > dropped into the water when A and A' are at the same location. The > wave the pebble creates propagates outward in all directions at the > same speed WITH RESPECT TO THE WATER. The wave the pebble creates > propagates outward in all directions at the same speed WITH RESPECT TO > A. That's true for water. What's true for light is this experimental observation: The speed of light approaching M from either direction is the same: c. The speed of light approaching M' from either direction is the same: c. The fact that what you say about water is true does not mean that the experimental facts about light I just listed are disputable. They aren't. > > When the wave the ripple makes in the water reaches the Observer at > M', has the wave traveled from A' to M' or from A to M'? The ripple > the pebble makes in the water travels from A to M'. A' is meaningless > when discussing the distance the wave travels to M'. > > The water is at rest with respect to the embankment. A flash of light > occurs when A and A' are at the same location. The light wave the > flash creates propagates outward in all directions at the same speed > WITH RESPECT TO THE WATER. The light wave the flash creates propagates > outward in all directions at the same speed WITH RESPECT TO A. > > When the light wave the flash makes in the water reaches the Observer > at M', has the wave traveled from A' to M' or from A to M'?
From: glird on 22 Dec 2009 10:23 On Dec 21, 5:13 pm, Michael Moroney wrote: > mpc755 writes: > >The problem with Einstein's train gedanken is it is assumed the state > >of the aether does not matter, but even Einstein punted on this one: > >'Ether and the Theory of Relativity by Albert Einstein' > >http://www-groups.dcs.st-and.ac.uk/~history/Extras/Einstein_ether.html > >"If we assume the ether to be at rest relatively to K, but in motion > >relatively to K', the physical equivalence of K and K' seems to me > >from the logical standpoint, not indeed downright incorrect, but > >nevertheless unacceptable." > > I think you need to read his next two sentences: "The next position which > it was possible to take up in face of this state of things appeared to be > the following. The ether does not exist at all." > > There are too many contradictions when trying to involve an aether. > Physicists wrestled with it many decades ago and generally came to the > conclusion that there is no need for an aether, and it likely simply does > not exist. This would be a "particle" artifact of the photon that all > "particles" in physics have with the wave/particle duality. A "particle" > has no need for a medium, just like a bullet doesn't need air (or anything > else) to shoot through. A bullet itself is a solid particle. If, then, a "bullet-particle" has no need for a medium, is it made out of nothing? I think you have to read Einstein's next paragraph: "More careful reflection teaches us however, that the special theory of relativity does not compel us to deny ether. We may assume the existence of an ether; only we must give up ascribing a definite state of motion to it, i.e. we must by abstraction take from it the last mechanical characteristic which Lorentz had still left it. We shall see later that this point of view, the conceivability of which I shall at once endeavour to make more intelligible by a somewhat halting comparison, is justified by the results of the general theory of relativity." glird
From: mpc755 on 22 Dec 2009 10:40 On Dec 22, 8:29 am, "papar...(a)gmail.com" <papar...(a)gmail.com> wrote: > On 22 dic, 09:48, mpc755 <mpc...(a)gmail.com> wrote: > > > > > On Dec 22, 6:57 am, "papar...(a)gmail.com" <papar...(a)gmail.com> wrote: > > > > The correct sentence is: > > > > The wave the pebble creates propagates outward in all directions at > > > the same speed WITH RESPECT TO THE LOCATION A/A' WHERE THE PEBBLE HIT > > > THE WATER. The wave the pebble creates propagates outward in all > > > directions at the same speed WITH RESPECT TO A/A'. > > > > > When the wave the ripple makes in the water reaches the Observer at > > > > M', has the wave traveled from A' to M' or from A to M'? The ripple > > > > the pebble makes in the water travels from A to M'. A' is meaningless > > > > when discussing the distance the wave travels to M'. > > > > Wrong!!! Once created the wave just propagates and eventually it will > > > reach the location of both observers M and M'. The hit point > > > coordinates exist in both frames of reference. So when you say A/A', > > > it means a point A with coordinates (-x_A,t_A) and a point A' with > > > coordinates (-x_A',t_A'). The light signal front is propagating with > > > some definite equations of movement involving the location of the > > > front (in terms of the coordinates (x,t) at the embankment frame and > > > (x',t') at the train frame). > > > 'Light signal front'? > > Have you ever drop a pebble into a pool? There are several concentric > waves propagating after the pebble hit the water. The first of all > those waves is the signal front, and you use it to define the > coordinates of the propagating signal. > > > We are discussing the WATER wave a pebble makes when it is dropped > > into the water when A and A' occupy the same point in three > > dimensional space. > > That is right, at a given time (say t=0 on the embankment frame K) > points A and A' coincide on a certain location (say when x=-x_A on > frame K). The coordinates of those two points are the following: > > Point A on frame K: (x,t)=(-x_A,0) > Point A' on frame K': (x',t')=(-x_A',t_A'), where x' and t' are > related through the Lorentz Transformation Equations. > > > Does the WATER wave the pebble creates in the water propagate outward > > at the same speed in all directions with respect to the water? > > Sure it does!, but with respect to its source coordinates. So it is an > expanding circle with center in points A/A' at the time the pebble hit > the water. > > > Yes, and since A is at rest with respect to the water, the WATER wave > > the pebble creates in the water propagates outward at the same speed > > in all directions with respect to A. A' is meaningless when discussing > > the propagation of the WATER wave. > > Wrong again!!! > > For instance if the pebble hit the water at time t=0 (as measured on > the embankment frame of reference), then the equation of movement of > the light signal on the frame K is: > > x(t)=ct-x_A > > The equation of movement of the same light signal, but now viewed from > the frame K' of the train is: > > x'(t)=ct'-x_A' > > So for sure that A and A' are both relevant to these calculations. > > Miguel Rios Yes, I have dropped pebbles into water and what occurs is the wave propagates outward in all directions at the same speed with respect to the water.
From: mpc755 on 22 Dec 2009 10:50 On Dec 22, 8:40 am, glird <gl...(a)aol.com> wrote: > On Dec 21, 12:39 pm, PD wrote: > > mpc755 wrote: > ><< Is the Observer at M able to measure to A and B in order to determine how far the light traveled to reach M? When the Observer measures to A and B and determines that A and B are equidistant from M, can the Observer at M conclude the lightning strikes occurred simultaneously? >> > > PD answered:>< Yes, of course he can measure from where he is standing to where there is a scorch mark left by the lightning, with a tape measure.. > > Yes, he can conclude that the lightning strikes occur simultaneously. > He needs to know the following things: > 1. That the distances traveled from A to M and from B to M are equal. > 2. That the speed of the light going from A to M and from B to M are > equal. knows also that the time it takes for the light to travel from > A to M equals the time it takes for the light to travel from B to M. > Therefore, if the light arrives at M at the same time, then the light > left A and B at a common earlier time. > (1) is determined by a measurement with a tape measure. > (2) is determined by isotropy experiments. > > > Dear mpc, > Please don't reply to any more arguments against your thesis on this > newsgroup! Although we disagree on some of the details, I will defend > your position from now on. Along the way it will become evident that > NONE of the physicists who've been attacking your thesis understand > STR any better than you do. > > glird Dear glird, I understand STR better than anyone. Do you understand the point I am trying to make with waves in water? Do you understand light waves travel with respect to the water? "In accordance with the principle of relativity we shall certainly have to take for granted that the propagation of light always takes place with the same velocity w with respect to the liquid, whether the latter is in motion with reference to other bodies or not." - Albert Einstein Do you understand if the water is at rest with respect to the embankment and if the Observer on the train knows everything in the Einstein train gedanken is moving relative to water at rest with the respect to the embankment and if the Observer on the train is able to determine the trains speed relative to the embankment then when the light from B' and then the light from A' reaches M', if the light from the lightning strikes at A and B reach M simultaneously, the Observer at M' will measure to B' and to A' and calculate when the lightning strikes occurred based on when the light from B' and A' reached M', while factoring in the light travels with respect to the water at rest with respect to the embankment, and the Observer at M' will conclude the lightning strikes at A/A' and B/B' where simultaneous, in nature? You have to understand the above sentence in order to understand light travels at 'c' with respect to the aether. mpc755
From: PD on 22 Dec 2009 10:54
On Dec 22, 9:50 am, mpc755 <mpc...(a)gmail.com> wrote: > On Dec 22, 8:40 am, glird <gl...(a)aol.com> wrote: > > > > > On Dec 21, 12:39 pm, PD wrote: > > > mpc755 wrote: > > ><< Is the Observer at M able to measure to A and B in order to determine how far the light traveled to reach M? When the Observer measures to A and B and determines that A and B are equidistant from M, can the Observer at M conclude the lightning strikes occurred simultaneously? >> > > > PD answered:>< Yes, of course he can measure from where he is standing to where there is a scorch mark left by the lightning, with a tape measure. > > > Yes, he can conclude that the lightning strikes occur simultaneously.. > > He needs to know the following things: > > 1. That the distances traveled from A to M and from B to M are equal. > > 2. That the speed of the light going from A to M and from B to M are > > equal. knows also that the time it takes for the light to travel from > > A to M equals the time it takes for the light to travel from B to M. > > Therefore, if the light arrives at M at the same time, then the light > > left A and B at a common earlier time. > > (1) is determined by a measurement with a tape measure. > > (2) is determined by isotropy experiments. > > > > Dear mpc, > > Please don't reply to any more arguments against your thesis on this > > newsgroup! Although we disagree on some of the details, I will defend > > your position from now on. Along the way it will become evident that > > NONE of the physicists who've been attacking your thesis understand > > STR any better than you do. > > > glird > > Dear glird, > > I understand STR better than anyone. Oh dear. Here is where you've gone off the deep end in a big way. And you can't swim. > > Do you understand the point I am trying to make with waves in water? > > Do you understand light waves travel with respect to the water? > > "In accordance with the principle of relativity we shall certainly > have to take for granted that the propagation of light always takes > place with the same velocity w with respect to the liquid, whether the > latter is in motion with reference to other bodies or not." - Albert > Einstein > > Do you understand if the water is at rest with respect to the > embankment and if the Observer on the train knows everything in the > Einstein train gedanken is moving relative to water at rest with the > respect to the embankment and if the Observer on the train is able to > determine the trains speed relative to the embankment then when the > light from B' and then the light from A' reaches M', if the light from > the lightning strikes at A and B reach M simultaneously, the Observer > at M' will measure to B' and to A' and calculate when the lightning > strikes occurred based on when the light from B' and A' reached M', > while factoring in the light travels with respect to the water at rest > with respect to the embankment, and the Observer at M' will conclude > the lightning strikes at A/A' and B/B' where simultaneous, in nature? > > You have to understand the above sentence in order to understand light > travels at 'c' with respect to the aether. > > mpc755 |