On Sep 10, 1:15*pm, PD wrote:
On Sep 10, 12:24*pm, Pentcho Valev wrote:
On Sep 10, 6:48*pm, PD wrote:
On Sep 10, 11:22*am, Pentcho Valev wrote:
On Sep 10, 6:02*pm, PD wrote:
On Sep 10, 9:19*am, Pentcho Valev wrote:
On Sep 10, 3:50*pm, PD wrote:
On Sep 10, 8:28 am, Pentcho Valev wrote:
Clever Draper what are you talking about. The travelling clock returns
PHYSICALLY different from the clock at rest (according to Divine
Albert's Divine Idiocy),
No, it doesn't. When it returns and is compared with the clock at
rest, the rates of the clocks are identical.
Don't lie, Clever Draper. When the travelling clock is compared with
the clock at rest, they are PHYSICALLY different (according to Divine
Albert's Divine Idiocy).
No, they show different rates when viewed from different reference
frames, but the clocks are physically identical. This is no different
than a car having a different kinetic energy when viewed from a
different reference frame, but it still being a physically unchanged
car.
It would help if you understood what Divine Albert actually said,
Pentcho.
Divine Albert said that, when the travelling clock returns, its hands
occupy different positions (compared with the hands of the clock at
rest).
Now that's what I call a PHYSICALLY different clock.
I think it would be rather foolish to call it that.
Two cars travel from Sofia to Varna, Bulgaria.
One car's odometer reads 468 km, and the other car's odometer reads
497 km, when they meet again in Varna. They of course did not travel
side-by-side.
Now, do you conclude from the fact that they have different readings
that the odometers are now (or ever were) physically different from
each other?
http://fr.youtube.com/watch?v=4vuW6tQ0218
"I'm not prepared to pursue my line of inquiry any longer as I think
this is getting too silly!"
Pentcho Valev
I agree. It got quite silly when you said that two clocks that show a
different reading when they meet again is an indicator that one of the
clocks was now physically different.
But, Clever Draper, if instead of clocks we discussed the famous
twins, one would be younger than the other when they meet again
(according to Divine Albert's Divine Idiocy). Would you claim again
that "younger" does not imply "physically different"? The travelling
clock is also "younger", Clever Draper (according to Divine Albert's
Divine Idiocy).
So is the odometer, Pentcho. It reads a different number. Nothing
physical happened to the odometer to alter how it records the passage
of path length. The two odometers can be tested, taken apart, and
there will be nothing that can be identified in either odometer that
says, "Well, this one is clearly different now."
Same thing with the twin. Nothing physical happened to either twin to
alter how it records the passage of path length. The fact that the
twin records (not with a number but with gray hair) a different path
length does not imply that anything physical has happened differently
to that twin.
Let me give you another example, Pentcho, something that Galileo would
understand and hopefully you will too.
A car is traveling, the front of the car pointed eastward to Belgrade,
and it applies its brakes, changing its velocity by 50 km/hr.
Now, in one reference frame, where a fire hydrant happens to be at
rest, this small sequence of events is recorded as follows: The car is
initially traveling at 80 km/hr to the east, applies its brakes, and
ends up at 30 km/hr toward the east. The acceleration is in the
direction opposite the initial velocity, obviously, and the kinetic
energy has been reduced as a result of the application of the brakes.
Now, in another reference frame, where a police cruiser happens to be
at rest, this VERY SAME sequence of events is recorded as follows: The
car is initially traveling at 10 km/hr to the west, applies its
brakes, and ends up at 60 km/hr toward the west. The acceleration is
in the *same* direction as the initial velocity, obviously, and the
kinetic energy has been increased as a result of the application of
the brakes.
(It shouldn't surprise you that the police cruiser is traveling 90 km/
hr relative to the fire hydrant.)
Now, if you think that something happened to the car from one or the
other reference frame to change the relative orientation of the
acceleration and initial velocity, or to change whether the kinetic
energy increases or decreases, perhaps you can identify what that
physical process was.
Also keep in mind that what I just laid out for you is a completely
Newtonian example, not a damn bit of Einsteinia in it.
PD