AOH :: CAPACITS.TXT Borderland: Intro to Dielectricity and Capacitance - E. Dollard
```

Introduction to
DIELECTRICITY AND CAPACITANCE
by Eric Dollard

CAPACITANCE
The phenomena of capacitance is a type of electrical energy storage in the form of a field
in an enclosed space.  This space is typically bounded by two parallel metallic plates or
two metallic foils on an intervening insulator or dielectric.  A nearly infinite variety of
more complex structures can exhibit capacity, as long as a difference in electric
potential exists between various areas of the structure.  The oscillating coil represents
one possibility as to a capacitor of more complex form, and will be presented here.

The perception of capacitance as used today is wholly inadequate for the proper
understanding of this effect.  Steinmetz mentions this in his introductory book Electric
Discharges, Waves and Impulses.  To quote, "Unfortunately, to  large extent in dealing
with dielectric fields the prehistoric conception of the electrostatic charge (electron) on
the conductor still exists, and by its use destroys the analogy between the two
components of the electric field, the magnetic and the dielectric, and makes the
consideration of dielectric fields unnecessarily complicated."

LINES OF FORCE AS REPRESENTATION OF DIELECTRICITY
Steinmetz continues, "There is obviously no more sense in thinking of the capacity
current as current which charges the conductor with a quantity of electricity, than there is
of speaking of the inductance voltage as charging the conductor with a quantity of
magnetism.  But the latter conception, together with the notion of a quantity of
magnetism, etc., has vanished since Faraday's representation of the magnetic field by
lines of force."

THE LAWS OF LINES OF FORCE
All the lines of magnetic force are closed upon themselves, all dielectric lines of force
terminate on conductors, but may form closed loops in electromagnetic radiation.
These represent the basic laws of lines of force.  It can be seen from these laws that any
line of force cannot just end in space.

FARADAY & LINES OF FORCE THEORY
Farady felt strongly that action at a distance is not possible thru empty space, or in other
words, "matter cannot act where it is not."  He considered space pervaded with lines of
force.  Almost everyone is familiar with the patterns formed by iron filings around a
magnet.  These filings act as numerous tiny compasses and orientate themselves along
the lines of force existing around the poles of the magnet.  Experiment has indicated that
a magnetic field does possess a fibrous construct.  By passing a coil of wire thru a
strong magnetic field and listening to the coil output in headphones, the experimenter
will notice a scraping noise. J. J. Thompson performed further experiments involving the
ionization of gases that indicate the field is not continuous but fibrous (electricity and
matter, 1906).

PHYSICAL CHARACTERISTICS OF LINES OF FORCE
Consider the space between poles of a magnet or capacitor as full of lines of electric
force.  See Fig.1.  These lines of force act as a quantity of stretched and mutually
repellent springs.  Anyone who has pushed together the like poles of two magnets has
felt this springy mass.  Observe Fig.2.  Notice the lines of force are more dense along
AB in between poles, and that more lines on A are facing B than are projecting outwards
to infinity.  Consider the effect of the lines of force on A.  These lines are in a state of
tension and pull on A.  Because more re pulling on A towards B than those pulling on A
away from B, we have the phenomena of physical attraction.  Now observe Fig. 3.  Notice
now that the poles are like rather than unlike, more or all lines pull A away from B; the
phenomena of physical repulsion.

MASS ASSOCIATED WITH LINES OF FORCE IN MOTION
The line of force can be more clearly understood by representing it as a tube of force or a
long thin cylinder.  Maxwell presented the idea the tension of a tube of force is
representative of electric force (volts/inch), and in addition to this tension, there is a
medium through which these tubes pass.  There exists a hydrostatic pressure against
this media or ether.  The value of this pressure is one half the product of dielectric and
magnetic density.  Then there is a pressure at right angles to an electric tube of force.  If
through the growth of a field the tubes of force spread sideways or in width, the
broadside drag through the medium represents the magnetic reaction to growth in
intensity of an electric current.  However, if a tube of force is caused to move endwise, it
will glide through the medium with little or no drag as little surface is offered.  This
possibly explains why no magnetic field is associated with certain experiments
performed by Tesla involving the movement of energy with no accompanying magnetic
field.

INDUCTANCE AS AN ANALOGY TO CAPACITY
Much of the mystery surrounding the workings of capacity can be cleared by close
examination of inductance and how it can give rise to dielectric phenomena.  Inductance
represents energy storage in space as a magnetic field.  The lines of force orientate
themselves in close loops surrounding the axis of current flow that has given rise to
them.  The large the space between this current and its images or reflections, the more
energy that can be stored in the resulting field.

MECHANISM OF STORING ENERGY MAGNETICALLY
The process of pushing these lines or loops outward, causing them to stretch,
represents storing energy as in  rubber band. A given current strength will hold a loop of
force at a given distance from conductor passing current hence no energy movement.  If
the flow of current increases, energy is absorbed by the field as the loops are then
pushed outward at a corresponding velocity.  Because energy is in motion an E.M.F.
must accompany the current flow in order for it to represent power.  The magnitude of
this EMF exactly corresponds to the velocity of the field.  Then if the current ceases
changing in magnitude thereby becoming constant, no EMF accompanies it, as no power
is being absorbed. However, if the current decreases and represents then a negative
velocity of field as the loops contract.  Because the EMF corresponds exactly to velocity
it reverses polarity and thereby reverses power so it now moves out of the field and into
the current.  Since no power is required to maintain a field, only current, the static or
stationary field, represents stored energy.

THE LIMITS OF ZERO AND INFINITY
Many interesting features of inductance manifest themselves in the two limiting cases of
trapping the energy or releasing it instantly.  Since the power supply driving the current
has resistance, when it is switched off the inductance drains its energy into this
resistance that concerts it into the form of heat.  We will assume a perfect inductor that
has no self resistance.  If we remove the current supply by shorting the terminals of the
inductor we have isolated it without interrupting any current.  Since the collapse of field
produces EMF this EMF will tend to manifest.  However, a short circuit will not allow an
EMF to develop across it as it is zero resistance by definition.  No EMF can combine
with current to form power, therefore, the energy will remain in the field.  Any attempt to
collapse forces increased currents which pushes it right back out  This is one form of
storage of energy.

INSTANT ENERGY RELEASE AS INFINITY
Very interesting (and dangerous) phenomena manifest themselves when the current path
is interrupted, thereby causing infinite resistance to appear.  In this case resistance is
best represented by its inverse, conductance.  The conductance is then zero.  Because
the current vanished instantly the field collapses at a velocity approaching that of light.
As EMF is directly related to velocity of flux, i tends towards infinity.  Very powerful
effects are produced because the field is attempting to maintain current by producing
whatever EMF required.  If a considerable amount of energy exists, say several kilowatt
hours* (250 KWH for lightning stroke), the ensuing discharge can produce most profound
effects and can completely destroy inadequately protected apparatus.
* The energy utilized by an average household in the course of one day.

ANOTHER FORM OF ENERGY APPEARS
Through the rapid discharge of inductance a new force field appears that reduces the rate
of inductive EMF formation.  This field is also represented by lines of force but these are
of a different nature than those of magnetism.  These lines of force are not a
manifestation of current flow but of an electric compression or tension.  This tension is
termed voltage or potential difference.

DIELECTRIC ENERGY STORAGE SPATIALLY DIFFERENT THAN MAGNETIC ENERGY
STORAGE
Unlike magnetism the energy is forced or compressed inwards rather than outwards.
Dielectric lines of force push inward into internal space and along axis, rather than
pushed outward broadside to axis as in the magnetic field.  Because the lines are
mutually repellent certain amounts of broadside or transverse motion can be expected
but the phenomena is basically longitudinal.  This gives rise to an interesting paradox
that will be noticed with capacity.  This is that the smaller the space bounded by the
conducting structure the more energy that can be stored.  This is the exact opposite of
magnetism.  With magnetism, the units volumes of energy can be though of as working
in parallel but the unit volumes of energy in association with dielectricity can be thought
of as working in series.

VOLTAGE IS TO DIELECTRICITY AS CURRENT IS TO MAGNETISM
With inductance the reaction to change of field is the production of voltage.  The current
is proportionate to the field strength only and not velocity of field.  With capacity the field
is produced not by current but voltage.  This voltage must be accompanied by current in
order for power to exist.  The reaction of capacitance to change of applied force is the
production of current.  The current is directly proportional to the velocity of field strength.
When voltage increases a reaction current flows into capacitance and thereby energy
accumulates.  If voltage does not change no current flows and the capacitance stores the
energy which produced the field.  If the voltage decreases then the reaction current
reverses and energy flows out of the dielectric field.
As the voltage is withdrawn the compression within the bounded space is relieved.
When the energy is fully dissipated the lines of force vanish.

AGAIN THE LIMITS ZERO AND INFINITY
Because the power supply which provided charging voltage has internal conductance,
after it is switched off the current leaking through conductance drains the dielectric
energy and converts it to heat.  We will assume a perfect capacitance having no leak
conductance.  If we completely disconnect the voltage supply by open circuiting the
terminals of the capacitor, no path for current flow exists by definition of an open circuit.
If the field tends to expand it will tend towards the production of current.  However, an
open circuit will not allow the flow of current as it has zero conductance.  Then any
attempt towards field expansion raises the voltage which pushes the field back inwards.
Therefore, energy will remain stored in the field. This energy can be drawn for use at any
time.  This is another form of energy storage.

INSTANT ENERGY RELEASE AS INFINITY
Phenomena of enormous magnitude manifest themselves when the criteria for voltage or
potential difference is instantly disrupted, as with a short circuit.  The effect is analogous
with the open circuit of inductive current.  Because the forcing voltage is instantly
withdrawn the field explodes against the bounding conductors with a velocity that may
exceed light.  Because the current is directly related to the velocity of field it jumps to
infinity in its attempt to produce finite voltage across zero resistance.  If considerable
energy had resided in the dielectric force field, again let us say several KWH the
resulting explosion has almost inconceivable violence and can vaporize a conductor of
substantial thickness instantly.  Dielectric discharges of great speed and energy
represent one of the most unpleasant experiences the electrical engineer encounters in
practice.

ENERGY RETURNS TO MAGNETIC FORM
The powerful currents produced by the sudden expansion of a dielectric field naturally
give rise to magnetic energy.  The inertia of the magnetic field limits the rise of current to
a realistic value.  The capacitance dumps all its energy back into the magnetic field and
the whole process starts over again.  The inverse of the product of magnetic storage
capacity and dielectric storage capacity represents the frequency or pitch at which this
energy interchange occurs.  This pitch may or may not contain overtones depending on
the extent of conductors bounding the energies.

CHARACTERISTIC IMPEDANCE AS REPRESENTATION OF PULSATION OF ENERGY FIELD
The ratio of magnetic storage ability to that of the dielectric is called the characteristic
impedance.  This gives the ratio of maximum voltage to maximum current in the
oscillatory structure.  However, as the magnetic energy storage is outward and the
dielectric storage is inward the total or double energy field pulsates in shape or size.
The axis of this pulsation of force is the impedance of the system displaying oscillations
and pulsation occurs at the frequency of oscillation.

ENERGY INTO MATTER
As the voltage or impedance is increased the emphasis is on the inward flux.  If the
impedance is high and rate of change is fast enough (perfect overtone series), it would
seem possible the compression of the energy would transform it into matter and the
reconversion of this matter into energy may or may not synchronize with the cycle of
oscillation.  This is what may be considered supercapacitance, that is, stable long term
conversion into matter.

MISCONCEPTIONS OF PRESENT THEORY OF CAPACITANCE
The misconception that capacitance is the result of accumulating electrons has seriously
distorted our view of dielectric phenomena.  Also the theory of the velocity of light as a
limit of energy flow, while adequate for magnetic force and material velocity, limits our
ability to visualize or understand certain possibilities in electric phenomena.  The true
workings of free space capacitance can be best illustrated by the following example.  It
has been previously stated that dielectric lines of force must terminate on conductors.
No line of force can end in space.  If we take any conductor and remove it to the most
remote portion of the universe, no lines of force can extend from this electrode to other
conductors.  It can have no free space capacity, regardless of the size of the electrode,
therefore it can store no energy.  This indicates that the free space capacitance of an
object is the sum mutual capacity of it to all the conducting objects of the universe.

FREE SPACE INDUCTANCE IS INFINITE
Steinmetz in his book on the general or unified behavior of electricity The Theory and
Calculation of Transient Electric Phenomena and Oscillation, points out that the
inductance of any unit length of an isolated filamentary conductor must be infinite.
Because no image currents exist to contain the magnetic field it can grow to infinite size.
This large quantity of energy cannot be quickly retrieved due to the finite velocity of
propagation of the magnetic field.  This gives a non reactive or energy component to the
inductance which is called electromagnetic radiation.

WORK OF TESLA, STEINMETZ AND FARDAY
In the aforementioned books of Steinmetz he develops some rather unique equations for
capacity.  Tesla devoted an enormous portion of his efforts to dielectric phenomena and
made numerous remarkable discoveries in this area.  Much of this work is yet to be fully
uncovered.  It is my contention that the phenomena of dielectricity is wide open for
profound discovery.  It is ironic that we have abandoned the lines of force concept
associated with a phenomena measure in the units called farads after Farady, whose
insight into forces and fields has led to the possibility of visualization of the electrical
phenomena.

QUESTION AS TO THE VELOCITY OF DIELECTRIC FLUX
It has been stated that all magnetic lines of force must be closed upon themselves, and
that all dielectric lines of force must terminate upon a conducting surface.  It can be
inferred from these two basic laws that no line of force can terminate in free space.  This
created an interesting question as to the state of dielectric flux lines before the field has
had time to propagate to the neutral conductor.  During this time it would seem that the
lines of force, not having reached the distant neutral conductor would end in space at
their advancing wave front.  It could be concluded that either the lines of force propagate
instantly or always exists and are modified or conjugate space exists within the same
boundaries as ordinary space.  The properties of lines of force within this conjugate
space may not obey the laws of normally conceived space.

IMPORTANT REFERENCE MATERIAL

1. Electricity and Matter, J. J. Thompson, New York, l906, Scribner's Sons, and l904,
Yale University.

2. Elementary Lecture on Electric Discharges, Waves, and Impulses and other
Transients, C. P. Steinmetz, second edition, 1914, McGraw-Hill.

3.  Theory and Calculation of Transient Electric Phenomena and Oscillations, C. P.
Steinmetz, third edition, l920, McGraw-Hill.  Section III Transients in Space, Chapter VIII,
Velocity of Propagation of Electric Field.

```

The entire AOH site is optimized to look best in Firefox® 3 on a widescreen monitor (1440x900 or better).