Re: GR ?


"Significant Zero" <paulpsremove@xxxxxxxxxx> wrote in message
news:1122061613.84099.0@xxxxxxxxxxxxxxxxxxxxxxx
>
> "Tom Roberts" <tjroberts@xxxxxxxxxx> wrote in message
> news:ImDDe.1901$fx4.1574@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx
> | Significant Zero wrote:
> | > "Tom Roberts" <tjroberts@xxxxxxxxxx> wrote in message
> | > news:lOYCe.673$lX2.670@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx
> | > [...]
> | > This seems to be saying that length contraction and time dilation are
> just
> | > observational distortions in the same way that railway lines get
> apparenly
> | > nearer as they extend to the horizon.
> |
> | Sort of -- both are effects of perspective, but different effects.
> |
> |
> | > Is this the way you explain to
> | > yourself the experimental variation in muon decay and contraction in
the
> | > direction of motion ?
> |
> | It is the way SR explains them. Just like rotations in 3D -- what
> | "explanation" do you use for the fact that a 10-foot-long ladder will
> | fit through a 3-foot-wide door in one orientation but not in another?
>
> Nice example but neither the doorway or the ladder change in physical
> reality only the relationship between the ladder and door.

And the same in SR - neither the coordinate system or the clock change in
physical reality only the relationship between them.

> The pov can
> change as much as it likes it still will not enable the ladder to fit
> through the door in the inappropriate orientation.

The same with SR - clocks will not measure time dilated unless they have the
appropriate 'orientation's wrt the coordinate system.

> The physical fact of the
> ladder and door are not changed by observation or measurement

The same with SR - the proper time is not changed either.

> and any
> measurement that fails to correct for factors it is aware are imbedded in
> its methodology needs a poke in the eye with a sharp stick.

And so does SR - which is why proper time is the only invariant time.

Bill

> BTW try a piano as they take no notice of observational distortion or
> perspective but are effected by gravity and velocity.{:-)
>
> | I say it is because the PROJECTION of the ladder's length onto the axis
> of
> | the door's width depends on their relative orientations.
>
> Yes as a physical fact.
>
> | Similarly in
> | SR, the PROJECTION of a rod's length, and the PROJECTION of a clock's
> | tick-interval, depend on their orientation relative to the measuring
> | apparatus. This is, of course, orientation in spaceTIME.
>
> This is not a physical fact its a observational or mathematically
engineered
> one and has no comparison or effect on the ladder or the doorway or rod
and
> clock.
> You appear to be mixing physical facts with observational and or
> mathematical ones and then forgetting which is which.
>
> |
> | On a Euclidean plane, the x' axis of Cartesian coordinates
> | rotated relative to x-y coordinates has a nonzero dy/dx.
> | In 2-d spacetime the x' axis of Minkowskian coordinates
> | rotated relative to x-t coordinates has nonzero dx/dt --
> | that is clearly a relative velocity. The rotation is of
> | course hyperbolic, not circular as in the Euclidean case.
> |
> |
> | > | > i.e A cubic meter of the vacuum state between galaxies
> | > | > has different characteristics to a cubic meter just outside an
event
> | > | > horizon[...]
> | >
> | > This may be difficult to explain but perhaps you will agree that a
clock
> in
> | > the in the two vacuum cases above will tick at different rates,
> |
> | No, I don't agree to that highly-ambiguous statement.
>
> Well I did not think it was particularly ambiguous as if you don't agree
to
> that then you must not agree that clocks generally run slower on earth
than
> in space and you must now have switched to the view that GR is invalid ?
>
> | Before you can say
> | anything about this you have to define how the rates of the two clocks
> | are compared. Once you realize that, you will realize that you cannot
> | possibly separate "difference in tick rate" from "effects on the signals
> | used to compare them".
> |
> | In GR this is modeled as geometry in spacetime. To do that the intrinsic
> | rate of a clock cannot depend on its environment.
>
> All the proof seems to contradict you as the intrinsic rate of clocks
> appears the be dependent on Gravityand and velocity.
>
> | For instance if you
> | define "comparison of tick rates" by placing a standard clock next to
> | each clock to be compared and then comparing those clocks to the
> | standard clocks, you will immediately see that their tick rates are the
> | same.
>
> Yes, because they are now in the same environment.
>
> |
> |
> | > so time
> | > according to the clocks is moving at a different rate ?
> |
> | The word "moving" does not apply to "time".
>
> I disagree, process is moving both in space and time.
>
> |
> | A simple way to avoid such nonsense is to remember that in physics
> | anything worth discussing must be MEASURABLE. How could one possibly
> | measure "motion of time"???
>
> With a clock.
>
> |
> |
> | > If so then if c is
> | > measured locally constant in these two environments but the clocks are
> | > running at different rates then actual length must have changed to
> | > accommodate the actual but locally unobservable change in c ?
> |
> | See above. You confuse yourself by attempting to use incomplete sound
> | bites to describe things instead of complete and detailed descriptions.
> |
> | Most people, especially around here, do not realize how important
> | precision in thought and word is. Modern physics is quite subtle, and
> | precision is ABSOLUTELY ESSENTIAL. My insistence on such precision is
> | not "nit picking", but is ESSENTIAL to understanding the concepts.
>
> That's fine but I would like to nit pick some of your statements
definitions
> and contradictions starting with your apparent contradictions with regard
to
> physical reality, observational reality, personal conceptual reality and
> common conceptual reality.
>
> |
> |
> | > | Certainly the Lagrangian of a system does not, in general, by itself
> | > | define energy. But if it is invariant over time translations then it
> | > | does (via Noether's theorem). And if it is not so invariant, energy
is
> | > | not so useful....
> | >
> | > That makes no sense to me as energy is a dynamic and the only
relatively
> | > static and invariant over time, form of energy that I can think of at
> the
> | > moment is a partical. Which implies that Lagrangian are not
applicable
> to
> | > energy of fields.
> |
> | You clearly do not understand Lagrangians. Study them. Don't merely
> | fling words around without understanding.
> |
>
> I might if I was convinced they applied to fields.
>
>
> |
> | > | The metric _IS_ the geometry.
> | >
> | > I tend to think as the metric as being [...]
> |
> | You clearly do not understand differential geometry. Study it. Don't
> | merely fling words around without understanding.
>
> Thanks you can snip you own statments and views as well.
>
> |
> |
> | > | And in general it is not possible to
> | > | "refer" a curved Lorentzian manifold to a "flat Euclidean geometry".
> | >
> | > I don't see the difficulty in overlaying one metric space with another
> and
> | > translating between them other than the complexity.
> |
> | You clearly do not understand differential geometry. Study it. Don't
> | merely fling words around without understanding.
> |
> | Specifically: the topology of a curved manifold can be, and usually is,
> | incompatible with the topology of a flat Euclidean manifold. So such
> | "referal" or "translating" is simply not possible.
> |
> | Why do you think that it is impossible to cover the surface
> | of a sphere with a single coordinate system? That is
> | directly related to the impossibility I discuss here.
> |
>
> Latitude and longitude seem a fairly good system.
>
> |
> | > In fact curvature is a
> | > Euclidean statement [...]
> |
> | Not true. You clearly do not understand differential geometry. Study it.
> | Don't merely fling words around without understanding.
>
> Perhaps you are pompously flinging concepts and words around without
> understanding them.
> --
> Significant Zero E-field = Electric field, M-field =Magnetic field, two
> unbound field effects
> http://home.freeuk.com/paulps/
> Maybe updates. (1-(1/(1/3))^2)/(1 + (1/(1/3))^2) = - 0.08 = FTL ? -p<+p
or
> (m*-v)<(m*+v) or (m*-c^2)<(m*+c^2) =g?
> .
> |
> |
> | Tom Roberts tjroberts@xxxxxxxxxx
>
>


.

Relevant Pages

  • Re: SR WITHOUT THE LIGHT POSTULATE?
    ... along a continuum of numbers is a clock. ... understanding the Shubertian model of spacetime. ... Axiomatization of Physics - Step 1". ...
    (sci.physics.relativity)
  • Re: The speed of gravity revisited
    ... clock experiences when the temperature increases: the clock slows, but nothing happens to real time as used to measure change in the universe at large. ... miracle means "an act of God". ... That is the meaning I intended in my use of the word in this physics context. ... the apple falls from the tree because there is a net graviton wind blowing down toward Earth because Earth blocks part of the graviton wind coming up from below. ...
    (sci.physics.relativity)
  • Re: Relativistic Physics - Science or Religion?
    ... >Modern physics, at least that part which is based upon Dr. Einstein's work, is ... >compared the time recorded by that clock with the time recorded by an identical ... He did not accept the possibility that the velocity of the trip ... but neither theory is a theory of gravity. ...
    (sci.physics)
  • Re: collection of ideas on relativity
    ... Take note that when we measure *anything* our measurements may ... It should be physics' goal in general to have all ... have a light-source and a light-detector, and perhaps a clock and a ... an amount of time while a light-clock *derives* an amount of time. ...
    (sci.physics.relativity)
  • Relativistic Physics - Science or Religion?
    ... Relativistic Physics - Science or Religion? ... physicist transported an atomic clock around the world on jet airliner and ... He did not accept the possibility that the velocity ... with a medium, called the Aether. ...
    (sci.physics.relativity)
Loading