Re: Clock synch


"Tom Roberts" <tjroberts137@xxxxxxxxxxxxx> schreef in bericht
news:kU9Dg.6016$9T3.619@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Nicolaas Vroom wrote:
"Nicolaas Vroom" <nicolaas.vroom@xxxxxxxxxx> schreef in bericht
news:ItWBg.10231$fQ5.270355@xxxxxxxxxxxxxxxxxxxxxxxx
"Tom Roberts" <tjroberts137@xxxxxxxxxxxxx> schreef in bericht
news:Z3SAg.3029$kO3.2790@xxxxxxxxxxxxxxxxxxxxxxxxxxxxx
There is no "time dilation", in the sense of a clock physically
ticking slower, or in the sense of "time moving slower". There is no
"shortening/elongating", in the sense of a given object physically
getting shorter or longer.

The effects called "time dilation" and "length contraction" in SR are
not physical effects, and are due to different measurement procedures
used by differently moving observers.

Suppose there are two Observers A and B at the same position P1
which both have identical clocks and which initially show the same value.
How would you call the effect, that, if those two Observers move
from P1 to P2 along a different path, that when they meet,
they realize that the two clocks show a different value ?
What is wrong by calling that a physical effect ?

There is nothing wrong with that, indeed that is what we mean by "physical
effect". But that is NOT "time dilation".

Accordingly to the book "Introducing Einstein's relativity" by
Ray d'Inverno at page 33 "Thus moving clocks go slow by a factor
SQR(1- v*v/c*c). This phenomenon is called time dilation."

IMO this is the situation I have described above.
(Implying that time dilation is a physical effect)
If Observer A stayed at home and Observer B did not than still
both moved from P1 to P2 along a different path.

As I have said so often, time dilation is the difference in projections
onto different coordinates.

How would you describe an experiment that demonstrates above

Your example involves the difference in elapsed proper time for different
paths between the same two points.

versus an experiment that demonstrates above.
What is the most important difference between the two ?
I expect that in both the Lorentz factor is involved.

In Euclidean geometry, the analogy to time dilation is the fact that a
meterstick held at 45 degrees relative to the X axis subtends only .707
meters along the X axis. The analogy to your example is a triangle ABC:
the path AB has a different path length than the path ACB.


Tom Roberts

Nicolaas Vroom
http://users.pandora.be/nicvroom/


.

Relevant Pages

  • Re: Clock synch
    ... or in the sense of "time moving slower". ... "shortening/elongating", in the sense of a given object physically ... Suppose there are two Observers A and B at the same position P1 ... What is wrong by calling that a physical effect? ...
    (sci.physics.relativity)
  • Re: Clock synch
    ... or in the sense of "time moving slower". ... Suppose there are two Observers A and B at the same position P1 ... which both have identical clocks and which initially show the same ... And accordingly to you what Rat described is not a physical effect? ...
    (sci.physics.relativity)
  • Re: Why does a multiplication by gamma > 1 result in a contraction?
    ... >> Let O and A be the traditional two observers, ... >> Now let A include a rod along the direction of travel of a known ... I'm not entirely sure how one can define the length of a moving ... Measure the velocity by using the two points on the ground. ...
    (sci.physics.relativity)
  • Re: I am Trying To Learn Relativity
    ... The postulate says that light travels at c in every frame. ... If an observer is moving relative to the coordinate ... The observers at rest measure light to travel at c relative to ... The closing speeds of c+v and c-v were calculated, ...
    (sci.physics.relativity)
  • Re: Was Einstein the most ignorant, immoral, stupid, dishonest plagerist,
    ... A and B are two observers. ... and now, as it is moving faster relative to A, it will be even shorter ... The rod is never longer that its proper length, no matter which iFoR it is ... In their own frame .. ...
    (sci.physics.relativity)
Quantcast