Python
2024-08-17 12:52:46 UTC
**An Interesting Case of Mental Blockage and Cognitive Dissonance:**
*Einstein-Poincaré Synchronization Procedure and Dr. Lengrand*
What’s fascinating about certain cranks is that just when you think
you’ve seen all the absurdities they can come up with, they manage to
produce something even worse. Their cognitive dissonance and ability to
pull out bizarre notions from who knows where, on top of a perfectly
well-defined technical procedure, is astonishing. We’ve seen this before
with GPS, where Hachel invents all sorts of fantasies, like atomic
clocks in the receivers or synchronization with a clock infinitely far
away in a fourth spatial dimension...
This is a report of exchanges on the synchronization procedure described
by Einstein in his 1905 paper, discussions that took place 17 years ago
and more recently on sci.physics.relativity and fr.sci.physique.
https://groups.google.com/g/fr.sci.physique/c/KgqI9gqTkR8/m/oMc9X0XjCWMJ
*Reminders on the Procedure:*
Two identical clocks, A and B, are stationary relative to each other at
a certain distance. Their identical functioning (within measurement
accuracy) allows us to assume that they "tick at the same rate." NOTHING
more is assumed, especially regarding the time they display; the purpose
is PRECISELY to adjust one of these clocks by applying a correction
after a calculation involving the values indicated on these clocks
during specific events, events that occur AT THE LOCATION OF EACH CLOCK.
Einstein’s procedure is not strictly a synchronization procedure but a
method to VERIFY their synchronization. This is the main difference from
Poincaré’s approach. However, it can be proven that Poincaré’s method
leads to clocks synchronized in Einstein’s sense. You can also transform
Einstein’s verification method into a synchronization procedure because
it allows calculating the correction to apply to clock A.
*Steps of Einstein's Method:*
When clock A shows t_A, a light signal is emitted from A towards B.
When this signal is received at B, clock B shows t_B, and a light signal
is sent from B back towards A.
When the signal is received at A, clock A shows t'_A.
The values t_A, t_B, and t'_A relate to events that all occur exactly at
the location of the clock displaying these measurements. They are
perfectly objective and independent of any observer. Anywhere in the
universe, whether at A, B, or on Andromeda, observers can obtain these
values (via astronaut carrier pigeons, for example).
Hachel/Lengrand manages to deny this simple FACT. This is the first
level of severe cognitive dissonance.
Einstein points out that the experiment (measuring time during round
trips, thus involving only one clock) justifies the formula: 2(AB)/(t'_A
- t_A) = c (*).
He then introduces a *convention*: t_B - t_A = t'_A - t_B (**).
Here, Hachel/Lengrand believes this is only possible if the clocks have
been specially pre-set, but there is nothing like that in Einstein’s
procedure. The point is *precisely* to check whether this formula holds
or not. And if it doesn’t, to find a way to make it true.
This shows Hachel/Lengrand’s ability to introduce additional conditions
out of nowhere (to put it politely) and then go completely off track
with objective values that don’t have the same value for everyone,
comparing it to an entirely irrelevant "Langevin-style" scenario...
*Epilogue: What to Do if (**) Is False??*
Starting from:
2(AB)/(t'_A - t_A) = c
t_B - t_A = t'_A - t_B
Elementary algebra allows us to express t_A in terms of the other
quantities involved:
t'_A = t_A + 2(AB)/c
t'_A = 2*t_B - t_A
=> t_A + 2(AB)/c = 2*t_B - t_A
=> 2*t_A = 2( t_B - (AB)/c )
=> t_A = t_B - (AB)/c
The value t_A should have been t_B - (AB)/c.
If the value was different, say t_Aerr, then adjust clock A by t_Aerr +
t_B - (AB)/c.
An operator at A knows all the involved values; either they’ve been
observed, known in advance (distance AB), or received via some transport
method (t_B).
The procedure works regardless of the initial settings of the two
clocks. We can then call the relationship (**) verified by the two
clocks as "A is synchronized with B" or "A synch B."
To validate this, we still need to verify that "synch" (under the
hypothesis 2(AB)/(t'_A - t_A) = c, which Hachel/Lengrand considers true!):
A synch A (reflexivity)
A synch B => B synch A (symmetry)
A synch B AND B synch C => A synch C (transitivity)
Einstein deemed it unnecessary to do this in his paper, considering it
obvious to his readership (he wasn’t there to preemptively manage cranks).
The procedure is also experimentally falsifiable, despite its
conventional aspect: by retesting synchronization after a minute, an
hour, a year, or a century for the same clocks left to run their course,
one would notice a desynchronization due to some phenomenon (except for
a technical defect in the clocks), which gives meaning to the often-read
phrase in popular science books: "time flows more or less quickly here
and there." Countless experiments validate this aspect of Einstein’s
procedure.
This procedure gives meaning to the coordinate "t" of an event for any
inertial reference frame (thus t', t'', etc.).
In General Relativity, we find this procedure with a limitation: it is
purely local; it holds in the spatiotemporal vicinity of an event. And
it must be taken into account that, by the definition of Gravitation,
two freely moving bodies (no acting forces) can see their trajectories
diverge or converge.
This subtlety sheds light on a circular aspect of physics (which is
entirely normal and quite a good sign): clocks are set to make Newton’s
first law true, and Newton’s first law allows clocks to be set
consistently (locally). Thanks to J. J. Lodder for pointing out this.
It’s no coincidence that the "real-time" event labeling proposed by
Hachel/Lengrand is incoherent in this sense: with such coordinates,
Newton’s first law is systematically violated; at worst, we even get a
speed ("apparent") that is not only variable but *discontinuous* (if the
body's trajectory crosses the observer).
I’ve written a small Python program that graphically demonstrates this
phenomenon:
https://gitlab.com/python_431/cranks-and-physics/-/tree/main/Hachel/code
*Einstein-Poincaré Synchronization Procedure and Dr. Lengrand*
What’s fascinating about certain cranks is that just when you think
you’ve seen all the absurdities they can come up with, they manage to
produce something even worse. Their cognitive dissonance and ability to
pull out bizarre notions from who knows where, on top of a perfectly
well-defined technical procedure, is astonishing. We’ve seen this before
with GPS, where Hachel invents all sorts of fantasies, like atomic
clocks in the receivers or synchronization with a clock infinitely far
away in a fourth spatial dimension...
This is a report of exchanges on the synchronization procedure described
by Einstein in his 1905 paper, discussions that took place 17 years ago
and more recently on sci.physics.relativity and fr.sci.physique.
https://groups.google.com/g/fr.sci.physique/c/KgqI9gqTkR8/m/oMc9X0XjCWMJ
*Reminders on the Procedure:*
Two identical clocks, A and B, are stationary relative to each other at
a certain distance. Their identical functioning (within measurement
accuracy) allows us to assume that they "tick at the same rate." NOTHING
more is assumed, especially regarding the time they display; the purpose
is PRECISELY to adjust one of these clocks by applying a correction
after a calculation involving the values indicated on these clocks
during specific events, events that occur AT THE LOCATION OF EACH CLOCK.
Einstein’s procedure is not strictly a synchronization procedure but a
method to VERIFY their synchronization. This is the main difference from
Poincaré’s approach. However, it can be proven that Poincaré’s method
leads to clocks synchronized in Einstein’s sense. You can also transform
Einstein’s verification method into a synchronization procedure because
it allows calculating the correction to apply to clock A.
*Steps of Einstein's Method:*
When clock A shows t_A, a light signal is emitted from A towards B.
When this signal is received at B, clock B shows t_B, and a light signal
is sent from B back towards A.
When the signal is received at A, clock A shows t'_A.
The values t_A, t_B, and t'_A relate to events that all occur exactly at
the location of the clock displaying these measurements. They are
perfectly objective and independent of any observer. Anywhere in the
universe, whether at A, B, or on Andromeda, observers can obtain these
values (via astronaut carrier pigeons, for example).
Hachel/Lengrand manages to deny this simple FACT. This is the first
level of severe cognitive dissonance.
Einstein points out that the experiment (measuring time during round
trips, thus involving only one clock) justifies the formula: 2(AB)/(t'_A
- t_A) = c (*).
He then introduces a *convention*: t_B - t_A = t'_A - t_B (**).
Here, Hachel/Lengrand believes this is only possible if the clocks have
been specially pre-set, but there is nothing like that in Einstein’s
procedure. The point is *precisely* to check whether this formula holds
or not. And if it doesn’t, to find a way to make it true.
This shows Hachel/Lengrand’s ability to introduce additional conditions
out of nowhere (to put it politely) and then go completely off track
with objective values that don’t have the same value for everyone,
comparing it to an entirely irrelevant "Langevin-style" scenario...
*Epilogue: What to Do if (**) Is False??*
Starting from:
2(AB)/(t'_A - t_A) = c
t_B - t_A = t'_A - t_B
Elementary algebra allows us to express t_A in terms of the other
quantities involved:
t'_A = t_A + 2(AB)/c
t'_A = 2*t_B - t_A
=> t_A + 2(AB)/c = 2*t_B - t_A
=> 2*t_A = 2( t_B - (AB)/c )
=> t_A = t_B - (AB)/c
The value t_A should have been t_B - (AB)/c.
If the value was different, say t_Aerr, then adjust clock A by t_Aerr +
t_B - (AB)/c.
An operator at A knows all the involved values; either they’ve been
observed, known in advance (distance AB), or received via some transport
method (t_B).
The procedure works regardless of the initial settings of the two
clocks. We can then call the relationship (**) verified by the two
clocks as "A is synchronized with B" or "A synch B."
To validate this, we still need to verify that "synch" (under the
hypothesis 2(AB)/(t'_A - t_A) = c, which Hachel/Lengrand considers true!):
A synch A (reflexivity)
A synch B => B synch A (symmetry)
A synch B AND B synch C => A synch C (transitivity)
Einstein deemed it unnecessary to do this in his paper, considering it
obvious to his readership (he wasn’t there to preemptively manage cranks).
The procedure is also experimentally falsifiable, despite its
conventional aspect: by retesting synchronization after a minute, an
hour, a year, or a century for the same clocks left to run their course,
one would notice a desynchronization due to some phenomenon (except for
a technical defect in the clocks), which gives meaning to the often-read
phrase in popular science books: "time flows more or less quickly here
and there." Countless experiments validate this aspect of Einstein’s
procedure.
This procedure gives meaning to the coordinate "t" of an event for any
inertial reference frame (thus t', t'', etc.).
In General Relativity, we find this procedure with a limitation: it is
purely local; it holds in the spatiotemporal vicinity of an event. And
it must be taken into account that, by the definition of Gravitation,
two freely moving bodies (no acting forces) can see their trajectories
diverge or converge.
This subtlety sheds light on a circular aspect of physics (which is
entirely normal and quite a good sign): clocks are set to make Newton’s
first law true, and Newton’s first law allows clocks to be set
consistently (locally). Thanks to J. J. Lodder for pointing out this.
It’s no coincidence that the "real-time" event labeling proposed by
Hachel/Lengrand is incoherent in this sense: with such coordinates,
Newton’s first law is systematically violated; at worst, we even get a
speed ("apparent") that is not only variable but *discontinuous* (if the
body's trajectory crosses the observer).
I’ve written a small Python program that graphically demonstrates this
phenomenon:
https://gitlab.com/python_431/cranks-and-physics/-/tree/main/Hachel/code