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Descent Thoughts (was - something and nothing)



 
 
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  #21  
Old June 28th 03, 09:40 PM
G=EMC^2 Glazier
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Default Descent Thoughts (was - something and nothing)

Odysseus You are wrong. Gravity is a particle attraction,and walking
between two mountains does try to pull at your body.(its in the books)
not to flame me. Bert

  #22  
Old June 28th 03, 09:54 PM
G=EMC^2 Glazier
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Default Descent Thoughts (was - something and nothing)

Hi oc I thought Wolter,and you would like my showing the blackhole
singularity,and the time before the big bang similarity I got two
emails that liked these thoughts,and they boosted my ego oc I'm
trying to think like Wolter some of the time,and hope to tickle both of
you. Bert

  #23  
Old June 29th 03, 03:54 AM
G=EMC^2 Glazier
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Default Descent Thoughts (was - something and nothing)

Hi Sally You say the pivot friction would slow the pendulum down. We
are now making magnetic bearings. No metal touching metal. In
your thinking the bob would go back and forth just like the spinning
disc. I don't think so. Bert

  #24  
Old June 29th 03, 11:50 AM
Sally
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Default Descent Thoughts (was - something and nothing)

But I do think so! Assuming no frictional losses of course. You still
haven't demonstrated a thought experiment where a frictionless system of
masses moving through G fields will lose energy.

Let us attack this from a different angle then....where does the energy from
the elevator go in your model? You have acknowledged that energy cannot be
destroyed. As the elevator slows down and the oscillations reduce in
amplitude the energy must be transferred away somehow. By what mechanism can
this happen?

By the way, try doing a Google search using "pendulum perpetual motion" and
some interesting stuff comes up. Some of it is thought provoking, some of it
downright wierd. I notice that there is frequently some confusion between
"perpertual motion" which is possible in our thought experiments and
"perpetual energy" machines which are supposed to supply energy forever. You
might need your silver foil hat for some of the latter sites g.

Sally

"G=EMC^2 Glazier" wrote in message
...
Hi Sally You say the pivot friction would slow the pendulum down. We
are now making magnetic bearings. No metal touching metal. In
your thinking the bob would go back and forth just like the spinning
disc. I don't think so. Bert



  #25  
Old June 29th 03, 08:33 PM
Bill Sheppard
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Default Descent Thoughts (was - something and nothing)

Bert, try picturing the oscillating pendulum this way - From 'way out in
space, look at the Earth-moon system directly from the side; the side-on
view shows the moon's orbit as a straight line. You only see the moon
moving from side to side, "stopping" at each end of the swing. This
might help visualize Sally's argument on why a frictionless pendulum
would never 'run down'.

oc

  #26  
Old June 29th 03, 08:48 PM
Sally
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Default Descent Thoughts (was - something and nothing)

Regarding the synchronising pendulums...I would need some pretty good
convincing that there was absolutely no mechanical or other coupling between
them before I abandoned my current world view. It smacks of dowsing, UFOs
and the like...

However...what would you say if I told you that I could design an
oscillating system that could respond to another oscillating system many
miles away? My system uses feather light electrons instead of a pendulum bob
and I reduce the friction in the system to a very low level so that the
merest hint of external influence will set it oscillating wildly. I also
make the resonant frequency of my oscillator the same as the distant one
because any coupling will be highly magnified if both oscillators actually
*want * to swing in synchronism. I activate the distant oscillator by
pouring electrical energy into it and my local set-up responds in kind!
Without any mechanical or electrical connection and over half a continent!

Magic? The end of physics as we know it? Well, yes it was ...in a way. When
Gugleilmo Marconi demonstrated it in 1894 after James clerk Maxwell had
hinted at the possibility of radio communication in his mathematical paper
of thirty years earlier.

Now...back to the energy loss thread...The energy needed to reverse
direction of the bob at the end of the swing is already contained in it. It
was stored as potential energy as the pendulum was rising, that is why it
slows down as it nears the end of the swing. Its kinetic energy gets
converted to potential energy. As the pendulum falls the potential energy
gets converted back to kinetic energy and it speeds up. Just like the
oscillating elevator. This is all well established school grade physics so
why do we need to postulate new theories of the universe when the existing
physical laws can explain everything that happens perfectly well? The words
"Occam" and "Razor" come to mind.

I have forgotten the point of this thread...was it something to do with
gravity and particles? My thoughts on that may not be too far from your
own...if gravity waves can be conclusively demonstrated then gravity
particles must then be accepted, in principle. Any wavelike property also
has a particle-like aspect as you will know. Of course, detecting such
particles is another matter entirely and I wouldn't expect such evidence to
crop up during such everyday observations as swinging pendulums or whatever.

This is turning into a "it does/it does not" sort of see-saw now so maybe it
is time to turn our minds to more constructive things and agree to
disagree...don't you think? Let us quit while it is still fun. g

Sally

"G=EMC^2 Glazier" wrote in message
...
Hi Sally Lots of fascinating things about pendulums Put a pendulum in a
room that's swing is out of step with the other pendulum in the room,and
in a few minutes their bobs swing in unison.(this helps Mach's inertia
theory). Pendulums near the poles align their swing to the stars(again
helping Mach's inertia theory) Sally you asked where the energy
would go if motion had no friction? The pendulum makes a arc(say a half
circle) at each end of the arc it comes to a complete stop lets say at
this stop point it is a rest.It now uses its kinetic energy to fall
back. I'm thinking some of its kinetic energy is lost because the bob
has inertia,and has to reverse its direction. Objects at rest want to
remain at rest,and energy is needed. This is where the energy will
go,and a pendulum in a vacuum with no friction at its pivot will swing
back and forth,but each swing will be a little shorter than the last.
Back and forth is not nearly as good as going round and round.
Bert PS Sally I could be wrong,but I'm going with my own thoughts on
this. My high IQ friends don't want me to go to google.



  #27  
Old June 29th 03, 10:45 PM
G=EMC^2 Glazier
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Default Descent Thoughts (was - something and nothing)

Hi oc I don't think stop and go action is as good as circular energy no
matter what. I think stop and go takes more energy than an object going
round and round. Pendulums stop and go. Nature uses spin,and
rotation. Never stop and go. I'm going with nature. Bert

  #28  
Old June 29th 03, 11:47 PM
Bill Sheppard
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Default Descent Thoughts (was - something and nothing)

Bert wrote,

I don't think stop and go action is as good as circular energy no

matter what. I think stop and go takes more energy than an object
going round and round. Pendulums stop and go. =A0 =A0 =A0 =A0 =A0 =A0

By golly you may be right after all, Bert, if the system's energy is
disspated by gravity-wave radiation. It's be awful small, and would take
a lonnnng time. Lessee what Sally thinks.

oc

  #29  
Old June 30th 03, 12:11 AM
Bill Sheppard
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Default Descent Thoughts (was - something and nothing)

To Sally, Bert, and gang-

The Taylor-Hulse binary pulsar reveals the first indirect evidence of GW
radiation, first predicted by Einstein in 1915. See-

www.psc.edu/science/Taylor/Relativity.html

oc

  #30  
Old June 30th 03, 12:46 AM
Sally
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Default Descent Thoughts (was - something and nothing)

Sally, you're failing to make the distinction between gravity and
'gravitational waves', which are two different critters.

No I'm not failing to make a distinction between them. I'm fully aware that
they would propagate outward from the oscillating source mass at C and I'm
aware of the distinction between gravity waves and gravity fields. I'm also
aware that they might be detected by small longitudinal changes in
dimensions of matter as they pass through it. So far, though, no experiment
has detected such waves. Presumably, current experiments are not sensitive
enough.

GW radiation
(if it's real) arises from oscillating masses or massive gravitational
events, and propagates as a longitudinal (compression-rarefaction) wave
(vis-a-vis EM radiation which propagates as a transverse wave, making it
subject to polarization).

As an aside, EM radiation contains two components, hence the name. I'm not
aware of more than one field component in the GW model, or the need for one.

GW radiation could more correctly be called a
'spatial acoustic pressure wave' in the fabric of space, propagating at
c. "Gravity-wave particles", or gravitons, would not be needed at all.
BUT if you believe space is functionally void (which
the mainstream almost universally does), then you do need the "messenger
particles"- flying photons, gravitons etc. to explain radiation thru
'nothingness'.

Yes, but...

There is at least one other option...we know that, at the quantum level, the
locations of particles can be "smeared" so that their position is not well
defined. One small modification to the math results in all particles being
smeared and having some minute chance of existing *anywhere*. According to
this view every particle is "smeared" throughout all of existence. They are
all touching and there is no such thing as "distance" and messengers are not
needed. The awkwardness of "action at a distance" through the void is no
longer needed.

Back to the distinction between gravity and GW
radiation- the distinction remains in place whether you believe in
void-space or the flowing-space model of gravity. Gravity remains a
centerward-bearing 'field', while GW radiation remains an outward-bound
flow of waves (or under void-space, "gravitons"). Don't feel bad- the
mainstream literature usually blurs the distinction, too, between
gravity and "gravity waves".

I don't feel bad, your paragraph is pretty much my understanding of the
concept.

In a previous reply to Bert, I suggested picturing the Earth-moon system
in side-on view to illustrate the pendulum idea. But since every
co-orbiting system presumably radiates GW energy, would not a
mechanically-frictionless pendulum also radiate GW energy? Though
miniscule, it would still represent a dissapative loss that will
eventually 'run down' the system. What do you think?

Yes, and if Bert had suggested that I may have agreed, but only after
allowing for a change in our original model to accept that specific
none-Newtonian dissipative feature. I was sort of skirting around the
subject of energy dissipation via GWs when I mentioned extreme accelerations
and masses falling into black holes a few posts back. I didn't pursue that
line of discussion at the time because we were still talking Newtonian
physics..at least..I was g. Bert...you reading this ?

It would seem to me that some of the energy of any object falling into a BH
would be radiated as a spike of gravitational energy. This would be more
like a gravitational shock wave than the continuous waves produced by
oscillating masses and I believe that if GWs are ever detected it will be as
these relatively strong single pulses long before GWs from orbiting masses
are ever detected.

Sally






 




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