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Spin and Energy
I enjoy reading The Industrial Physicist,
since I’ve spent most of my career in practical
applications of physics. I am surprised
to find the article “Spin
and energy—free?” (Briefs, item 2)
in the August/September
issue. Apart from
my skepticism, this is not an “applied
research and product development” subject,
but one of fundamental physics. In my opinion,
applied research should be practiced
with all the quality control and peer review
of fundamental research. This subject should
go through the normal scientific-journal evolution
of review, publication, and independent
checking before the applications community
is alerted to it.
Victor van Lint
Consultant
La Jolla, California
[A. O. Wistrom replies: The experimental
observations of Coulomb torque have been
published in Refs. 4 and 5, where we also
presented the results of the asymptotic
analysis of the predicted torque. Furthermore,
in order to set the stage for the full
theoretical derivation of Coulomb torque,
we derived the general expansion of the surface
potentials for a three-dimensional system
comprising N spherical conductors that
was published in Ref. 6, following the procedures
outlined in Ref. 2*. Finally, the theoretical
basis for Coulomb torque was published
in Ref. 3*. So far, our research has
been published in four reputable and peerreviewed
journals, which testifies to the
soundness of the work.
*See Reprise, The
Industrial Physicist,
October/November]
The news brief on three-body Coulomb
forces, which seem to induce increasing spin
in charged spheres with no outside energy
transfer, shows a monopole charge distribution
as it is presented. The effect depends on
the electromechanical asymmetry of three
monopoles induced in the three spheres, if I
read the brief correctly. Wouldn’t it be more
correct to represent the charge distribution
as multipole? For example, in the two-sphere
case with axial symmetry, the monopoles
would represent the net charges at the center
of the spheres, while the induced charge
asymmetry would give rise to two coaxial
dipoles, one in each sphere, with their negative
charges facing each other. Similarly, the
three-sphere case should give rise to a multipole
distribution, which I cannot visualize
without an analysis. I think the dynamics of
the system would change if higher-order
multipoles and their interactions were introduced.
These would be different from monopole
interactions. Then energy would probably
be conserved.
But perhaps Wistrom’s analysis included
this. I am unable to comment on the experiment
without seeing the data, and I should
really look up the J. Phys. A reference before I
try. But I can visualize a situation in which
energy is added to the system as charge
flows into the fixed sphere, enough to add
the torsion energy to the suspension wires.
Charles W. Lear
Ogden, Utah
[A. O. Wistrom replies: The theoretical
analysis is based on a multipole expansion
of the potentials using a recently published
expression that accounts for an arbitrary
number of spheres in three-dimensional
space (6). We find that the addition of the
third sphere introduces an asymmetric surface
charge distribution with
both polar and azimuthal
dependencies that do not
cancel for other than a perfect
equilateral arrangement
of equal spheres and when
the spheres are linearly
arranged. Indeed, we find it
is the higher-order multipoles
that give rise to the
observed Coulomb torque.]
With regard to the article “Spin
and energy—free?” I
would hope that actual experiments with
the conducting spheres are performed in
such a way as to take into account the
effect that a rotating sphere has in the presence
of Earth’s magnetic field. As we know,
a moving conductor in the presence of a
magnetic field produces a potential in the
conductor, and also a current, if there is a
return path. For the case of the sphere, the
resulting current produces a magnetic field
of its own which opposes the inducing
field. I point this out only because of how
easy it is to forget something so often taken
for granted.
Ivan Cowie
Time Domain Corp.
Huntsville, Alabama
[A. O. Wistrom replies: The experiments
were electrostatic and were performed with
the conducting spheres held stationary
in space.
References
4. Wistrom, A. O.; Khachatourian, A. V. M. Appl. Phys. Lett. 2002,
80 (15), 2800–2801;
correction 81 (25), 4871.
5. Khachatourian, A. V. M.; Wistrom, A. O.
Europhys. Lett. 2002, 59 (4), 521–525: correction
60 (2), 330.
6. Khachatourian, A. V. M.; Wistrom, A. O.
A sum rule for associated Legendre polynonomials
with sphere triangles. J. Math.
Phys. 2002, 44 (2), 849–852; correction 44
(2), 849–852.]
I was disappointed to see the article “Spin
and energy—free?” in the August/September
issue. The articles referenced present theoretical
and experimental results that suggest
that a net rotation can be imparted to sets of
conducting spheres by the introduction of
an electric potential.
The brief, however, seems to have extrapolated
these results to an energy-and-spinfor-free situation. It implies
that, in theory, an arrangement of three spheres could transfer
unlimited amounts of energy into the
spinning spheres—a violation of conservation
of energy. The authors of those papers
do not make a claim in this regard in either
of the original papers. In fact, in the earlier
paper, the first figure shows a schematic of
the experimental setup, with a power supply
clearly indicated. One of the authors of
those original papers (A. O. Wistrom) is
quoted in the diagram caption, but it is not
clear whether the authors were shown an
advance copy of this brief. I doubt they are
pleased with the association of their work
with claims of perpetual motion.
I teach physics to undergraduates and I
like to bring in just-published articles and
discuss them with the class. The Industrial
Physicist is especially relevant because of its
real-world feel. Undergraduates, however,
like much of the general public, seem to
have an exaggerated hope that perpetual
motion devices, time travel, travel faster
that the speed of light, etc., are possible.
Finding such a brief in a publication of the
American Institute of Physics (AIP) is a
potential educational setback of mammoth
proportions. I understand that The Industrial
Physicist is not meant to be a teaching
tool. Still, an AIP publication should edit
its content more carefully, especially during
The World Year of Physics.
Joseph O. West
Department of Physics
Indiana State University
Terre Haute, Indiana
[Author replies: It is the
policy of The Industrial Physicist (TIP) to have researchers
review all news briefs for
accuracy in advance of publication,
and this brief was
no exception. In reviewing the article, A. O.
Wistrom emphasized that angular momentum
is conserved in the system. But he
agreed that, in his view, a torque would be
continuously applied on two of the spheres.
With a low-friction bearing, this would lead
to a continous spin-up. Since the third
sphere was kept at a fixed potential, but, in
Wistrom’s view, passed no current, it would
not be providing energy. Thus, Wistrom’s
work does describe an apparent violation of
conservation of energy.
We decided nonetheless to publish a
description of this work, sensational as it
was. The news brief itself made clear the
problems, both theoretical and experimental,
with the reported work. When a startling
claim is published in respected journals,
it is only appropriate that news
publications like ours draw the attention of
the community to such work so that its
validity can be discussed and, hopefully,
tested by further experiment or explained
in a less surprising way.
In my view, the letters we received show
that we are succeeding in this intent. The
first letter, by George Levin, proposes a plausible
alternative explanation, in the form of a
corona discharge current that would supply
the energy needed to produce a spin.
In reporting spectacular claims, there are two pitfalls of science
journalism. One of these is to
dismiss all “unorthodox”
claims. This risks overlooking
real advances, which
almost always seem
unorthodox at first. The
other is to uncritically
report the latest speculations
(such as “dark energy,” “wormholes in space,” and so on), which tends, as you fear,
to blur the line between science and science fiction.
In this case, TIP has tried to avoid both pitfalls
with fair, but skeptical, reporting.
Your students could find this process of
publication-and-reply a good example of
how the scientific community can sift
through spectacular claims in a positive way.
Eric Lerner]
The Grid
Thanks for the informative and sensible
analysis of the recent electric grid problems
(“What’s wrong with the electric grid?” by
Eric J. Lerner). As you point out, the solution proposed
by the Department of Energy, the
Federal Energy Regulatory Commission,
and their masters at the Electric Power
Research Institute and the Edison Electric
Institute will largely benefit energy traders
at the expense of consumers—just another
example of the recent trend of “government
of the people, by the stooges, for the
fat cats.” As you also point out, the start of
a responsible solution—if “our” government
is actually interested in serving the
people instead of the profiteers—is to
repeal Order 888. I, for one, am not holding
my breath until the day that happens.
Kim L. Ground
Automation Specialist
Tampa, Florida
Great issue as usual, but the article “What’s wrong with the electric grid?” was
outstanding. It was the first intelligent story
I’ve read on the subject. Good job.
Jimmie Hutchison
Dominion Environmental
Phoenix, Arizona
I read Eric J. Lerner’s article about the
problems with our national power grid and
found it enlightening and disconcerting.
Lerner’s explanations of the physics and
realities of the North American power grid
explain clearly why we had a blackout and
why we will have more in the future.
I was unprepared for the politics and
greed of the situation. I understand electricity,
and I understand the concept of deregulation.
I had always assumed that deregulation
meant more independent generating plants
within a specific locale selling power into the
local power grid. I never envisioned deregulation
to mean selling power across local
boundaries. That is ludicrous.
Lerner’s suggested solution for a return
to regulated power monopolies is a step in
the wrong direction. Instead, I suggest that
power sales be limited regionally and
directed to local consumers and/or distributors.
If power generation facilities want to
sell into other grids in the same manner
that Quebec sells into the Northeast, then
the generator should be responsible for
owning, buying, or leasing unilateral transmission
facilities. The solution is: Local
power sale/free transmission—Wholesale
remote power sale/pay for the wiring.
The issue of reactive power can also be
addressed. Local transmission facilities
would be required to farm out reactive
power requirements to match power generation
purchases and, in this manner, better
utilize the system and get direct financial
feedback for the cost of reactive power.
I don’t think the citizens of North America
should pay for extensive remote-transmission
wiring to facilitate
a boondoggle in
remote-power commerce.
The additional taxpayer
cost is not necessary and
comes with no financial
feedback, whereas requiring
the generator to lease
lines between sites gives
direct financial incentive
to create power transmission
lines without burdening the taxpayers.
Congress could assist in this matter by
making the creation of transmission lines
less onerous than they are now due to local
and fringe civil resistance.
Bob Strachan
Lake George, New York
Thank you for your most informative
article, “What’s wrong with the electric
grid?” Although this problem is not a topic
I deal with in my job, my degree is in
physics, and I wish to make a few remarks.
First there is the economic problem of
reactive power. Generating sources should be
economically compensated, mostly in terms
of required kVA, not just wattage. It may not
be politically possible to reverse all of Order
888, at least in a timely manner, but this economic
adjustment must get a high priority.
Similarly, stress factors that are not as susceptible
to this approach—such as distance
between power source and consumption—
should be appropriately taxed. The tax could
be made more palatable by returning the revenue
to research, information sharing, or
another related central resource. Finally,
information hoarding must be illegal. In the
case of the federal government, we have the
Freedom of Information Act. The same reasoning
can be applied to force the industry
to make vital information public. As long as
all parties are treated with equal fairness, no
legitimate business will be hurt, and all will
benefit from such an open exchange.
George Warner
Computer systems engineer
Chantilly, Virginia
In treating the electric grid as a single
machine, you do not go far enough. The
lion’s share of peaking load is now represented
by air conditioning. The major
change since 1965 is that air conditioning
has become ubiquitous. Furthermore, the
vast majority of air conditioners have thermostats.
They get switched on in the
spring and switched off in the fall, and, for
practical purposes, they are part of the single
machine. The single machine is automatically
trying to respond to the weather.
Temperature fluctuations do not cancel
over large areas. A scorching day in New
York may be a byproduct of a wind blowing
from Mexico, and its effects are naturally
on a continental scale. I think the parable
of King Canute and the tide is applicable.
The electric machine’s great weakness is
its bureaucratic ignorance of half of its
plant. If you think in whole-system terms,
you can install large numbers of geothermal
heat pumps at attractive prices, thus
reducing temperature-induced fluctuations.
Similarly, in many climates, solar
water heaters with large storage tanks are
immensely attractive. Householders are
reluctant to plunk down, say, $5,000 for
new equipment. Their marginal source of
credit is likely to be unsecured consumer
credit (e.g., credit cards) at about 25%
interest. What electric utilities can do is to
act as “risk assumers,” undertaking to heat
and cool a building to within stated limits
for a stated monthly price.
Andrew D. Todd
Morgantown, West Virginia
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