Re: what is the relation between force and energy?
From: Andr? Michaud (srp_at_microtec.net)
Date: 10/17/04
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Date: 17 Oct 2004 05:39:44 -0700
greenfield_7@hotmail.com (Jim Greenfield) wrote in message news:<3c4afb26.0410162055.4ad882e6@posting.google.com>...
> srp@microtec.net (Andr? Michaud) wrote in message news:<562f286c.0410160230.74cb60dd@posting.google.com>...
> > greenfield_7@hotmail.com (Jim Greenfield) wrote in message news:<3c4afb26.0410151738.659621f1@posting.google.com>...
>
> > > > Presently, it mathematically boils down to zero at the center simply
> > > > because all of Earth's matter is "above" it in all directions, and
> > > > "pulls" about equally from all sides. Gravity being zero at the
> > > > center cannot mean anything more.
> > >
> > > Yes. Tricky how the gravity force is changed from a one directional
> > > (squashing the soles of my feet) to a "pressure" at the earth center-
> > > like all points outside that center trying to get to the opposite
> > > position!
> >
> > I am not certain I get your take here.
> >
> > The reason gravity holds you against the surface is that all of
> > the matter making up the Earth (and attracting you) is under you,
> > so all of it is pulling you down.
>
> I'm trying not to get too side-tracked here, but the pull towards the
> earth's center is only the net result of adding all the vector forces
> (attractions) which exist between every particle and every other
> particle.
Yes.
> Point being that IF the earth's mass was ALL at the center,
> the force on me would be vastly greater (all acting in the same
> direction)
No really, despite your impression. It would be exactly the same.
For all practical purposes, it is acting as if it all came from the
same direction.
In Newtonian gravitation, all calculations are made precisely as
if all of the mass was concentrated in the center.
When calculating the orbit of satellites, the radius used for
the orbit is the distance between the center of the Earth and
the orbit, not the distance between the satellite and the surface
of the Earth.
It has been mathematically established by Newton, and constantly
confirmed afterwards, that if the Earth was a homogenous sphere (it
is not, but it is close enough for the purpose), in fact, all
calculations for objects lying at the surface or moving above the
surface can be made as if the whole mass of the Earth was concentrated
at its center. It is one of the great discoveries/conclusions of Newton.
> I don't know if this is relevent to us, but in a binary star
> system??....or when orbiting bodies have much greater densities or
> differences in densities??
Then the center of mass of the binary system is the point at which
rotation equilibrium of the system is reached. If both stars have
similar masses, then this center will lie somewhere between the two
bodies for example.
> > If you were at the center, in a hypothetical cavity that would
> > prevent the pressure from crushing you and the heat from frying
> > you, all of the matter making up the Earth would be just about
> > equally spread around you, pulling from every direction.
> >
> > So, in whatever direction you would look, half of Earth's mass
> > would be in front of you and half would be behind you, both halves
> > pulling equally on you.
>
> as above
> >
> > In a newtonian set up, where force is involved, matter attracts
> > matter. Every particle attracts all other particles.
>
> Yes
>
> > Newton did not know about charged particles, but if force is
> > involved, the effect would be the same, since all stable matter
> > making up our bodies and the matter making up the planet is
> > made of stable, charged and scatterable particles (electrons,
> > quarks up and quarks down).
> >
> > > > > Therefore clocks should run (according to GR) at different
> > > > > rates.
> > > >
> > > > Very perceptive... if spacetime dilation was real. But see below
> > > > about clocks.
> > > >
> > > > > So how come both the core and the atmosphere complete an orbit
> > > > > of the sun in exactly the same time (whatever that may be).
> >
> > > > > The observation that the core isn't on the other side of the
> > > > > sun by now, is enough to make me bin GR right there!
> > > >
> > > > Common sense. The very same can be said about the atmosphere,
> > > > since at 10000 meters, clocks are already "verified" to run
> > > > faster than at ground level, so the question is why is the upper
> > > > atmosphere still orbiting the Sun at the same rate as the Earth.
> > >
> > > As in my reply to Tom, under SR time would fluctuate, but average the
> > > same. It obviously does not.
> >
> > My opinion also. I came to the conclusion that time is invariant.
> >
> > > > But again, see below for atomic clocks.
> > > >
> > > > > Clocks malfunction - time is invariant - end of story
> > > >
> > > > Common sense conclusion. But atomic clocks do not really malfunction.
> > > > it only is the interpretation of the measure that is warped to appear
> > > > to support SR and GR.
> > > >
> > > > Atomic clocks do not really run faster in altitude. They are just
> > > > electronically compensated to always match a very specific frequency
> > > > of ceasium (or hydrogen in hydrogen based clocks). But since these
> > > > frequencies increase with altitude (for reasons that have nothing to
> > > > do with time), it is interpreted as proof for SR and GR defenders
> > > > that time runs faster when gravitation decreases.
> > >
> > > I don't suppose you can send me to a link diagramatically describing
> > > atomic clocks?
> >
> > There are tens of links on the net talking about it, but none that
> > I scanned explains the real operation. I didn't have the patience
> > to scan them all.
> >
> > However, I can refer you to very clean source that you can go check
> > in just about any library, if you don't have the book yourself.
> > It is in one of the most popular and respected undergrad textbooks
> > around.
> >
> > "PHYSICS", by Halliday and Resnick.
>
> Thank you
> >
> > In the 1967 edition, you will find a complete description in pages
> > 7 to 11, with a clean schematic on page 9.
> >
> > They obviously believe that it means that times runs faster with
> > altitude as all physicists currently do, but you can draw your
> > own conclusions.
> >
> > Hydrogen and some other materials are also used in other types
> > of atomic clocks, but they all operate on the same principle.
> >
> > > I have long suspected that they rely on c=c+v, and that the Doppler
> > > you hint at ("compensated to always match a very specific frequency")
> > > is due to changed photon speed
> >
> > It has been thoroughly demonstrated that the speed of photons does
> > not change. What they do instead, when their energy increases is to
> > cycle faster (increase in frequency), just like lowering its energy
> > lowers its frequency instead of slowing it down.
>
> Beg to differ. I've looked for years, and am yet to find an experiment
> where two light pulses are "raced" (compared), when one pulse was
> emitted from a moving source, and another from a stationary one ref
> that location, at the same instant.
> All I found was a million reasons" from DHR's that such a race is not
> admissable when attacking SR
Someone has been trying to fool you then, because you are describing
the doppler effect. Same speed of all photons is what this effect
is based on. Doppler radars are used precisely to measure the speed
of objects, intensely used in the military as well as in civilian
applications.
> I maintain that the increase in energy of the photon is of a kinetic
> nature,
You are absolutely right. Photons energy is kinetic (it is a greek word
that means "motion". Photons are quanta of free electromagnetic energy
in inertial motion.
> as the photon is going faster.
I am not going to try to convince you, of course, but here is a little
info that you may possibly check.
The speed of light has been established approximately many centuries
ago (Roemer) and with rather high precision as far back as the mid 1800's
by many observers.
It can also be calculated with high precision from Maxwell's equations
and cleanly matches observation. In fact, it was Maxwell who discovered
that that speed is a property of free electromagnetic energy.
It is not a conclusion of SR. It is more fundamental than SR or
any other theory. It is a property of free moving energy.
If you dig into Halliday and Resnick or any other undergrad textbook,
you will find the equations and explanation.
c (speed of light) can also be calculated from the measured frequency
or wavelength of photons, it is the product of frequency and wavelength
of any photon
c = lambda nu
If the wavelength (lambda) is long, the frequency will be slow enough
for their product to give the speed of the photon (c). If the wavelength
is short, then the frequency will faster in such a way that their
product will still give the same speed.
They always match.
Doppler ranging radars would not work if this was not the case, and
they work fine with a high degree of precision.
If you read on the doppler effect, you will see why it couldn't
work if the speed of light could vary in a homogenous medium.
> > > (changing the observed frequency)
> >
> > More than simply an "observed" frequency, it also is the real
> > physical frequency.
> >
> > Frequencies emitted by quantum jumps from a specific orbital to
> > a lower specific orbital can increase for only one possible reason
> > in such circumstances, and it is that the nucleus attraction would
> > increase with altitude, which means that its mass has increased.
> >
> > Only one thing can do that, a tightening of the local orbits of the
> > captive up and down quarks that make up the nucleons, which causes
> > an increase in their relativistic inertia, thus their effective mass.
> >
> > Since these clocks are constantly monitored to recalibrate by
> > comparing the current chosen frequency of photons emitted by a
> > microwave oscillator to energize ceasium atoms, what is seen as
> > a measure of time dilation is the increase in frequency that the
> > oscillator must emit for the resulting beam of ceasium atom to
> > continue hitting the target as altitude increases.
>
> Part of my position is that gravity slows out-going photons. This may
> be significant here.
Absolutely, and very significant. In the case of photons, that "slowing"
takes the form of a loss of energy. It is called gravitational red-shift.
They lose energy as they climb against gravity, which diminishes their
frequency, but they still move at c. They lose energy instead of
slowing down.
For photons coming in with gravity, the opposite effect is observed.
They blue-shift, which means that their energy is increased, wich
increases their frequency (and shorten their wavelength) but they
still come in at c.
> > One point of interest is that this apparent time "dilation" exists
> > only for such atomic clocks. Mechanical clocks continue to give
> > perfectly synchronized time in these conditions.
>
> Yes. Funny how SR supporters are perfectly happy with mechanical
> clocks, until results come in which disagree with SR :-)
Yes. It is one of their invariant characteristic :-]
André Michaud
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