Re: A funny kind of rectilinearity


Tom Roberts wrote:
> msadkins04@xxxxxxxxx wrote:
> > Tom Roberts wrote:
> >>The light always propagates with SPEED c in any inertial
> >>frame, but its direction in any frame clearly depends on the orientation
> >>of the source in that frame.
> >
> > I hope you're not suggesting that in one frame the laser is pointed
> > toward the detector, whereas in another frame the laser is pointing
> > toward an empty section of space where the detector will be in future,
> > and that the empty section of space the detector points toward is
> > different for every such frame.
>
> This depends on what you mean by "point". If you mean something like
> "the centerline of the laser extended along its length simultaneously",
> then yes -- the sticky point is that "simultaneously". If you mean the
> actual direction the beam takes, then no.

I didn't say "point", I said pointed.

>
>
> > Either the laser is pointing
> > toward the detector, in which case it does so in every frame, or else
> > the laser is pointed into space (but then we have the absurd conclusion
> > that the angle between laser and detector is different for every
> > frame).
>
> This does not make sense -- two objects do not determine any sort of
> "angle".

It does make sense, nitwit, because I've already explicitly stated that
the angle in question is the angle between the source/detector line and
the direction of motion of S' (according to S). That you are unable to
"comprehend" this obvious relation implicitly without a constant
explicit repetition, demonstrates just how brittle and off-base your
"comprehension" is.

>
>And look above for the ambiguity in your "pointing".

No ambiguity. Either the laser points to the detector or not, as per
my earlier comments. Only a dullard would find this ambiguous enough
to be confusing. Are you sure you aren't an artificial intelligence
program? They seem to have a great deal of trouble interpreting
English, even when perfectly well-formed by human grammatical
standards.

>
> But if the laser beam hits the detector when viewed from one frame, it
> of course does so when viewed from any other frame. Note my phrasing --
> objects are not "in" any frame; frames are used for viewing only (i.e.
> measuring). Of course objects can be "at rest in" a given frame, but
> that is quite different from being "in" the frame (which implies
> exclusivity which is not possible).
>
>
> >> BTW this is true in Newtonian physics for light or any object
> >> with finite speed, such as cannonballs -- drive past a cannon
> >> firing vertically, and in the frame of your car the cannon is
> >> not aimed straight up (where "aimed" is defined by where the
> >> cannonball goes, not necessarily the orientation of the cannon
> >> itself).
> >
> > Yes, but in Newtonian physics velocities are additive and it makes
> > perfect sense that something sharing the scalar component of a velocity
> > vector should share the directional component as well. When the scalar
> > component isn't shared, as in SR, it's rather puzzling that the
> > directional component is shared.
>
> You confuse yourself by attempting to separate "scalar part" from
> "directional component". The transforms most naturally relate the
> components of _vectors_ (3-vectors in NM, 4-vectors in SR).

I don't confuse *myself* about this, you obfuscatory fool.

>
> > The relative motion is observed, but the attribution of that motion to
> > either of the two frames is an assumption. That is, it is an
> > *assumption* that frame S' is moving (the assumption of S), and it is
> > an *assumption* that frame S' is at rest (the assumption of S').
>
> No. You are caught up in old-fashioned words. There is no "at rest",
> there is only "at rest relative to S" (or S'). There is no "moving",
> there is only "moving relative to S" (or S').

Yes. I am not caught up in old-fashioned words. I explicitly said
above that the "movement" of S' is "the assumption of S" and that the
"rest" state of S' is "the assumption of S'". Go back to SR
kindergarten, little boy, if you can't even get this stuff straight.

>
>
> > Either a frame is moving, or it is not. [...]
>
> That seems to me to be the central part of your error and confusion.
> There is no "moving", there is only "moving relative to S" (or S').
>
>
> Tom Roberts tjroberts@xxxxxxxxxx

Try reading what I actually wrote, nitwit, instead of pretending that I
wrote something different and then falsely attributing confusion on the
basis of your misrepresentation.

Mark Adkins
msadkins04@xxxxxxxxx

.

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