Re: The real twin paradox.

"Sue..." <suzysewnshow@xxxxxxxxxxxx> wrote in
news:5d2cac2e-2244-452b-b4e1-cd72dfad444d@xxxxxxxxxxxxxxxxxxxxxxxxxxxx:

[...]
http://www.fourmilab.ch/etexts/einstein/specrel/www/

He concludes that the laws of relative motion apply to light, to
electrons and to all ponderable masses.

We of course know that is not true.
Light beams would replace thrusters if it were.

'WE' do NOT know that.

first, the statement I gave above says NOTHING about imponderable masses
such as light exerting pressure so your response is off target. second,
light DOES exert pressure. finally, the use of high intensity light beams
as a rocket thruster (as opposed to using ground based lasers to push
payloads into space) is prohibited by two laws:
1) the law against using
high energy beam weapons to destroy launch pads (the ship would vaporize
the launch pad) and
2) the batteries to drive the laser are kind of
heavy.
I have worked with a 500 Watt CW laser. It would take a small
moving van to move it with another for the 20,000 volt at 20 amp power
supply.

It would only produce 500 Newton meters/second of thrust, or 369
ft lbf/s of force.

Hardly enough to accelerate the power supply plus laser plus sue-bungee-
type extension cord.

Yes, nuclear fusion could supply enough power to make it worth while, but
we might as well use the laser and the fusion reaction to push the 'ash'
[helium] away and gain even more of a boost.

http://en.wikipedia.org/wiki/Radiation_pressure
http://www.u.arizona.edu/~lilley98/

[quote http://www.technovelgy.com/ct/content.asp?Bnum=694]
The existence of light pressure was demonstrated as theoretically possible
by James Clerk Maxwell in 1873. Confirming laboratory experiments waited
until the turn of the century. [unquote]

[quote http://www.livescience.com/technology/070327_laser_jet.html]
Physicists know that the heat of lasers can move liquid. But this test
found that the light itself, not heat, did the pushing. [unquote]

[quote http://www.springerlink.com/content/rx72j316032p4148/]
Summary Attention is paid to the effect of light pressure, completely
ignored in the present explanations on the energetics of dynamical
processes in atmosphere. It seems even to be of great importance and play
a great role, especially in the upper atmosphere. It seems there are three
phenomena produced probably by this process: 1) Appearing of the earth
atmosphere tide on the night side. 2) Presence of strong west winds on the
great altitude. 3) Vertical oscillations of the upper atmosphere density.
[unquote]

[quote http://www.esc.cam.ac.uk/Library/Journals/J.Conf.Abs./1/222.html]
Contrary to bigger meteoroids which are controlled by gravitational
interactions dynamics of submicron-sized particles is dominated by
radiation pressure and by electromagnetic interactions with the
interplanetary magnetic field. [unquote]

Finally, to see light pressure in action, just observe the tails of
comets. They always point away from the sun because the pressure of the
light drives them away from the sun. [that is not to say that the solar
particle 'wind' has no effect, but the effect seen is the sum of several
effects INCLUDING light pressure].

.....
For this reason
E. Mach demanded a modification of the
law of inertia in the sense that the
inertia should be interpreted as an
acceleration resistance of the bodies
against one another and not against "space".
This interpretation governs the expectation
that accelerated bodies have concordant
accelerating action in the same
sense on other bodies (acceleration induction).
This interpretation is even more
plausible according to general relativity
which eliminates the distinction between
inertial and gravitational effects.
It amounts to stipulating that, apart
from the arbitrariness governed by the
free choice of coordinates, the
gm v -field shall be completely determined
by the matter. Mach's stipulation is favoured
in general relativity by the circumstance
that acceleration induction in accordance
with the gravitational field equations really
exists, although of such slight intensity
that direct detection by mechanical experiments
is out of the question. >>
http://nobelprize.org/nobel_prizes/physics/laureates/1921/einstein-lectur
e.html

Conformablily with popular notions does not justfiy
the use of Lorenz gauge and improper transformations.

We have established that four light paths may be unequal in length.
How does that violate causality, the speed of light or PoR ?

Causality is only violated by the transmission of information faster than
light. This has never been observed.

73



Perhaps bowing to experimental evidence goes against your preference
for obfuscation via random citation but TRY READING for understanding.

The Nobel prize lecture says nothing about light clocks acting differently
than ponderable clocks, nor does it say that light exerts no pressure, nor
does it say that the Lorentz-Einstein transforms for time have no reality.

Nothing you have cited make any statement that support your contentions
that time is absolute. And when you make your extension cord 'stretchy'
signals sent down it will show the same doppler shifts as signals
transmitted through the dielectric medium of space.


--
bz

please pardon my infinite ignorance, the set-of-things-I-do-not-know is an
infinite set.

bz+spr@xxxxxxxxxxxxxxxxxxxx remove ch100-5 to avoid spam trap
.

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