Some troubling assumptions of SR

"Lester Zick" wrote in message
...
On 13 Feb 2007 10:09:03 -0800, (Daryl
McCullough) wrote:
...
Fact is that your usage is longer and leaves the impression that an
object can be "not at rest" in a frame of reference.

And that impression is the correct impression. If I specify a
reference frame F, then some objects are at rest in that frame,
and some are not.

Then in SR they're in different reference frames.

In your question, objects A and B define a common frame
but object C is moving in that frame, and of course A
and B are moving in the rest frame of C.

George

On Feb 13, 12:54 pm, Lester Zick wrote:

As I recollect most recently on this current thread DvdM lectured
on the commonly held opinion that "time is what a clock measures"
and I had the temerity to ask what a clock was?

Franz Heymann wrote on Nov. 14, 2002:
"A clock is a device which executes a...repeatable periodic motion.
Objects in an ensemble of different kinds of object which are
suspected of being clocks may be sorted into the category 'clock'
by grouping together all those which keep in step. By a pair
keeping in step I mean that if B completes b cycles whenever A
completes a cycles, then b/a is a conserved quantity. Elapsed time
is proportional to the number of cycles of motion completed by a
clock. Any arbitrary one of a collection of clocks may be chosen
to be the one for which the constant of proportionality is deemed
to be 1. From then on, that specimen defines the units in which
time is measured....The ensemble of objects must be at the same
place and in the same state of motion when the sorting is done....
In the case of a pendulum oscillating in a gravitational field,
the clock is not the pendulum, but the pendulum earth combination."

Satisfied?

Jerry

Daryl McCullough wrote:


Okay, I see that you lack certain prerequisites for discussing
physics. You don't know what a rotation is? Do you know what a
coordinate system is?

He is devoid of any mathematical understanding. Our Boy Zick is on a par
with one of Aristotle's C+ students. About 2300 years behind the times.

Bob Kolker

Daryl McCullough wrote:
Lester, you lack all the basics in understanding physics. It doesn't
make any sense for me to go through each and every one of your comments
and explain what's wrong with them. What's a much more efficient use of
everyone's time is for you to take some introductory course in physics.
I would gladly go through it with you online.

He won't. He is a Legend in His Own Mind.

Bob Kolker

Lester Zick wrote:



Unfortunately you don't. Says more for retards than you.

The most common type of clock is a harmonic oscillator. That works for
everything from a grandfather clock (a kind of pendulum clock) to a
quartz crystal timing circuit to an atomic clock.

Clocks based on harmonic oscillators will keep in pretty good step with
each other. I say "pretty good" because mechanical clocks are affected
by friction and temperature effects so they don't keep "perfect time".
That fact that clocks tend to stay in step with each other, at least for
a limited duration, leads to the metaphysical assumption of time
independent of clocks.

People have been using periodic or cyclic phenomenon to "keep time"
since the dawn of the human race. Our first clock was the earth with the
apparent motions of the sun, the moon and the stars resulting from the
revolution of the earth about its axis.

Bob Kolker

Dirk Van de moortel says...

Daryl, still not convinced that you're dealing with a troll?
Sorry - couldn't resist :-)

It seems to me the hypothesis that Lester is just *very*
ignorant fits the observations. But since he's not interested
in actually learning anything, I'm putting him in my killfile.
Lately, I'm trying to follow the rule that if person A is
likely to never learn anything from me, and I'm not likely
to ever learn anything from person A, then I should just
avoid discussions with him completely. As I will with
Lester from now on.

Actually, Lester was already in my killfile from sci.logic,
but I hadn't added him to my sci.physics.relativity or sci.math
killfiles.

--
Daryl McCullough
Ithaca, NY

Lester Zick says...

Nor do I understand exactly what you mean by "events" and
"distance between" since "events" are presumably temporal in nature
and "distance" a metric.

Then you need to back up and actually learn Special Relativity.

Well it might help if you could explain what you're talking about
first.

You don't have the prerequisites, Lester. Start with Cartesian
coordinate systems. Learn about rotations and translations.
Then when you're comfortable with that, learn about Galilean
transforms and Newtonian physics. At that point, you will be
in a position to talk about Special Relativity.

--
Daryl McCullough
Ithaca, NY

"Jerry" wrote in message oups.com...
On Feb 13, 12:54 pm, Lester Zick wrote:

As I recollect most recently on this current thread DvdM lectured
on the commonly held opinion that "time is what a clock measures"
and I had the temerity to ask what a clock was?

Franz Heymann wrote on Nov. 14, 2002:
"A clock is a device which executes a...repeatable periodic motion.
Objects in an ensemble of different kinds of object which are
suspected of being clocks may be sorted into the category 'clock'
by grouping together all those which keep in step. By a pair
keeping in step I mean that if B completes b cycles whenever A
completes a cycles, then b/a is a conserved quantity. Elapsed time
is proportional to the number of cycles of motion completed by a
clock. Any arbitrary one of a collection of clocks may be chosen
to be the one for which the constant of proportionality is deemed
to be 1. From then on, that specimen defines the units in which
time is measured....The ensemble of objects must be at the same
place and in the same state of motion when the sorting is done....
In the case of a pendulum oscillating in a gravitational field,
the clock is not the pendulum, but the pendulum earth combination."

Satisfied?

Ah, good old Franz. He left us way too soon.
Thanks for digging this up, T :-)

Replace the phrase "repeatable periodic motion" with "countable
process" and the circularity is removed.
See messages 1 up to (and including!) 17 of thread
http://groups.google.com/group/sci.p...45722d11389de1
Have a look at the little discussion between Franz, Gregory and
Mati, and specially at puppet_sock's remark. I'm with him and
with Greg on this.
Franz agreed that he was happy to call the above a good definition
of a "perfect clock", which i.m.o. is a mere philosophical issue.
No one in the world uses perfect clocks. They use clocks, and
no physicist should need a definition of a clock, just like a
philosopher doesn't need a definition of pencil and paper to do
his job, and just like Lester's dentest doesn't need a definition
of teeth do start working on Lester's.

Dirk Vdm

"Bob Kolker" wrote in message ...
Lester Zick wrote:



Unfortunately you don't. Says more for retards than you.

The most common type of clock is a harmonic oscillator. That works for
everything from a grandfather clock (a kind of pendulum clock) to a
quartz crystal timing circuit to an atomic clock.

Clocks based on harmonic oscillators will keep in pretty good step with
each other. I say "pretty good" because mechanical clocks are affected
by friction and temperature effects so they don't keep "perfect time".
That fact that clocks tend to stay in step with each other, at least for
a limited duration, leads to the metaphysical assumption of time
independent of clocks.

People have been using periodic or cyclic phenomenon to "keep time"
since the dawn of the human race. Our first clock was the earth with the
apparent motions of the sun, the moon and the stars resulting from the
revolution of the earth about its axis.

Armchair philosopers like Chester are not impressed by what
humatity has been doing since its dawn. They have decided that
time can not be defined without circularity, and to that purpose,
when you tell them to count their heart beat to see how many
beats it takes to see someonre run from here to there, they panic
and go: "Surely, it can't be *that* simple? What about Kant then???"

Dirk Vdm

On Feb 14, 3:15 am, "Dirk Van de moortel" dirkvandemoor...@ThankS-NO-
SperM.hotmail.com wrote:

Ah, good old Franz. He left us way too soon.
Thanks for digging this up, T :-)

You guessed right with "T". I only knew Franz a little bit, but
T knew him well, and remembered this one right away.

Jerry