THE ENERGETIC VACUUM: IMPLICATIONS FOR ENERGY RESEARCH

 Reproduced below, with the permission of the author, is a paper written by Dr.

Harold E. Puthoff, a respected physicist in quantum electrodynamics (QED) and

in the relatively new field of stochastic electrodynamics (SED).  This paper

originally appeared in Speculations in Science and Technology, vol. 13, no. 4,

pp. 247-257, 1990.  The reader is encouraged to obtain a copy of the original

paper since the figures could not be reproduced here in ASCII.

This paper speculates, using current theories, that *net* energy MIGHT (and

only might) be extractable from the vacuum of space.  Such a possibility does

not necessarily violate current thermodynamic laws since all we need to do is

to redraw our thermodynamic boundaries to include the vacuum energy of the

universe and its attributes.  Dr. Puthoff is currently pursuing experimental

studies to ascertain whether or not there is tappable "excess" energy in the

vacuum (theoretical considerations cannot ascertain the answer to this although

there are several possible reasons why it could exist).  Since the publication

of this paper, some preliminary experimental results by Dr. Puthoff and his

associates using a "condensed charge technology device" indicate that the

vacuum indeed has significant "excess" energy that is tappable;  further work

to make sure of their results (to avoid the problems that plagued the cold

fusion controversy), and eventual publication will be done.  A patent has

already been granted on this device:  Patent Number 5,018,180, "Energy

Conversion Using High Charge Density..."

As an interesting aside, in my conversation with Dr. Puthoff recently, he

believed that anomalous heat generation observed in several "cold fusion"

experiments was not fusion, rather it was vacuum energy extraction (either net

energy extraction from vacuum energy "excess", or vacuum energy charging and

later extraction similar to a battery).  This could explain why any anomalous

heat generation was not accompanied by a neutron and radiation signature

indicating nuclear fusion.  Thus, I'm cross-posting this to the fusion energy

newsgroup for their comment.

The reader is also referred to four other related papers by Dr. Puthoff which

appeared in the literature (three appeared in Physical Review):

"Ground State of Hydrogen as a Zero-Point-Fluctuation-Determined State",

Physical Review D, vol. 35, no. 10, pp. 3266-3269, 15 May 1987.

"Gravity as a Zero-Point-Fluctuation Force", Physical Review A, vol. 39, no. 5,

pp. 2333-2342, 1 March 1989.

"Source of Vacuum Electromagnetic Zero-Point Energy", Physical Review A, vol.

40, no. 9, pp. 4857-4862, 1 November 1989.  See also his replies to comments in

Physical Review A, vol. 44, no. 5, page 3382 and 3385-3386, and an Erratum in

Physical Review A, vol. 41, no. 5, page 2902.

"Everything for Nothing", New Scientist, pp. 52-55, 28 July 1990.

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-Beginning of Paper-

THE ENERGETIC VACUUM:  IMPLICATIONS FOR ENERGY RESEARCH

H.E. Puthoff

Institute for Advanced Studies at Austin

1301 Capital of Texas Highway S., Suite A-232

Austin, TX 78746

(512) 346-9947

"The existence of an actual vacuum was a subject of debate among scientists

from Aristotle into the twentieth century.  Since light, magnetic fields and

heat all travel through a vacuum, something must be there.  Borrowing a word

from Aristotle, scientists described various kinds of 'aethers' that exist in

even the hardest vacuum and that pervade space.  Maxwell's theory of electro-

magnetism reduced these different types to just one, called the ether.  Various

experiments were developed to detect this ether, of which the most famous was

the Michelson-Morley experiment, which failed to find it.  Finally, in 1905,

Einstein banished the ether by means of special relativity and allowed the true

vacuum to exist.

"But not for long.  The Heisenberg uncertainty principle of 1927 led particle

physicists to predict that particles would arise spontaneously from the vacuum,

so long as they disappeared before violating the uncertainty principle.  The

quantum vacuum is a very active place, with all sorts of particles appearing

and disappearing.  Careful experiments have demonstrated that the quantum

theorists are correct in this interpretation of the vacuum...  Furthermore,

starting in 1980 with the theory of the inflationary universe, particle

physicists have told us that the entire universe was created as a 'false

vacuum', a quantum vacuum that has more energy in its nothingness than it

should.  The decay of that particular vacuum to an ordinary quantum vacuum

produced all the mass in the universe and started the Big Bang."

From "The Timetables of Science", Simon and Schuster, 1988

INTRODUCTION

Modern physical theory, specifically quantum electrodynamics (QED), tells us

that the vacuum can no longer be considered a void.  This is due to the fact

that, even in the absence of matter, the vacuum is neither truly particle nor

field free, but is the seat of virtual particle-pair (e.g. electron-positron)

creation and annihilation processes, as well as zero-point-fluctuation (ZPF) of

such fields as the vacuum electromagnetic field, which will be the focus of our

study here.

Formally, the energy density associated with the vacuum electromagnetic ZPF

background is considered to be infinite.  With appropriate high-frequency

cutoffs the ZPF energy density is still conservatively estimated to be on the

order of nuclear energy densities or greater.[1]  The enormity of the figures

describing the vacuum electromagnetic zero-point energy raises the question as

to whether these numbers should be taken seriously, whether they are due to

some defect or misinterpretation of the theory, whether the ZPF fields ought to

be considered as 'virtual' or 'real'.[2]  There is, however, no question but

that the ZPF fields lead to real, measurable physical consequences.  One

example is the very real Casimir force,[3-6] an experimentally-verified [7-9]

ZPF-induced attractive quantum force between closely-spaced metal or dielectric

plates.  An elegant analysis by Milonni, et al., at Los Alamos National

Laboratory shows that the Casimir force is due to radiation pressure from the

background electromagnetic zero-point energy which has become unbalanced due to

the presence of the plates, and which results in the plates being pushed

together.[10]  (We will discuss this effect in more detail later when we

address the possibility of ZPF energy extraction.)  Other effects which can be

traced back to interactions involving the ZPF fields in a fundamental way

include the Lamb shift (the slight perturbation of the emission lines seen from

transitions between atomic states),[11-13] the van der Waals chemical binding

forces,[14] the stabilization of atomic structure against radiative collapse,

[15-16] quantum field mechanisms underlying the gravitational interaction,[17]

and spontaneous emission.[18]

ZERO-POINT ENERGY

To understand just what the significance of zero-point energy is, let us begin

with a simple harmonic oscillator as shown in Figure 1.  According to classical

theory, such a harmonic oscillator, once excited but with excitation removed,

will come to rest (because of friction losses) as shown in Figure 1(a).  In

quantum theory, however, this is not the case.  Instead, such an oscillator

will always retain a finite amount of 'jiggle', as shown in Figure 1(b).  The

average energy (kinetic plus potential) associated with this residuum of

motion, the so-called zero-point energy, is given by: <E>= hw/2, where 'h' is

Planck's constant (h= 1.054e-34 joule/sec) and 'w' [really 'omega'] is the

frequency of oscillation.  The meaning of the adjective 'zero-point' is that

such motion exists even at a temperature of absolute zero where no thermal

agitation effects remain.  Similarly, if a cavity electromagnetic mode is

excited and then left to decay, as shown in Figure 2, the field energy dies

away, again to a minimum value <E>= hw/2 (half a photon's worth), indicating

that fields as well as mechanical systems are subject to zero-point

fluctuations.  It is the presence of such ZPF 'noise' that can never be gotten

rid of, no matter how perfect the technology, that sets a lower limit on the

detectability of electromagnetic signals.

If we now consider the universe as a whole as constituting a giant cavity, then

we approach a continuum of possible modes (frequencies, directions) of

propagation of electromagnetic waves.  Again, even in the absence of overt

excitation, quantum theory has us assign an <E>= hw/2 to each mode.  

Multiplication of this energy by a density of modes factor [19] then yields

an expression for the spectral energy density that characterizes the vacuum

electromagnetic zero-point energy

rho(w)dw = [w^2/pi^2*c^3]/[hw/2]dw 

         = (hw^3)/(2*pi^2*c^3)dw  joules/m^3            (eqn. 1)

There are a number of properties of the zero-point energy distribution given in

equation 1 that are worthy of note.  First, the frequency behavior is seen to

diverge as w^3.  In the absence of a high-frequency cutoff this would imply an

infinite energy density.  (This is the source of such statements regarding a

purely formal theory.)  As discussed by Feynman and Hibbs, however, we have no

evidence that QED remains valid at asymptotically high frequencies (vanishingly

small wavelengths).[1]  Therefore, we are justified in assuming a high-

frequency cutoff, and arguments based on the requirements of general relativity

place this cutoff near the Planck frequency (~10^-33 cm).[17]  Even with this

cutoff the mass-density equivalent of the vacuum ZPF fields is still on the

order of 10^94 g/cm^3.  This caused Wheeler to remark that "elementary

particles represent a percentage-wise almost completely negligible change in

the locally violent conditions that characterize the vacuum...In other words,

elementary particles do not form a really basic starting point for the

description of nature.  Instead, they represent a first-order correction to

vacuum physics."[20]  As high as this value is, one might think that the vacuum

energy would be easy to observe.  Although this is true in a certain sense (it

is the source of quantum noise), by and large the homogeneity and isotropy

(uniformity) of the ZPF distribution prevent naive observation, and only

departures from uniformity yield overtly observable effects.

Contributing to the lack of direct observability is a second feature of the ZPF

spectrum;  namely, its Lorentz invariance.  Whereas motion through all other

radiation fields, random or otherwise, can be detected by Doppler-shift

phenomena, the ZPF spectrum with its cubic frequency dependence is unique in

that detailed cancellation of Doppler shifts with velocity changes leaves the

spectrum unchanged.  (Indeed, one can derive the ZPF spectrum to within a scale

factor by simply postulating a Lorentz-invariant random radiation field.

[21,22])  Thus, although any particular component may Doppler shift as a result

of motion, another component Doppler shifts to take its place.  It is also the

case, again unique to the ZPF cubic-frequency-dependent spectrum, that Doppler

shifts due to other phenomena (e.g., cosmological expansion, gravitation) also

do not alter the spectrum.  [23]  This stands in contrast to, for example, the

3 K blackbody (thermal) microwave background left over from the Big Bang which

cools with cosmological expansion.

Yet another feature of the ZPF spectrum, related to its Lorentz invariance and

again unique in comparison with all other competitors, is the complete lack of

a drag force on a charged particle passing through it.  This is because such a

drag forced (the so-called Einstein-Hopf drag [24]) is proportional to the

factor [rho(w) - (w/3)*(d rho/dw)], and this vanishes identically for

rho(w) ~= w^3.

On the other hand, accelerated motion through the vacuum can in principle

reveal the presence of the ZPF energy density directly.  Unlike uniform motion

in which delicate cancellations of Doppler shifts leave the motion undetected,

in accelerated motion the Doppler-shift cancellations are no longer sustained.

As a result, the Lorentz-invariant spectrum which holds in uniform motion is

augmented by additional terms.  One factor yields a thermal (Planck) spectrum

of temperature T= h*a/2*pi*c*k, where 'a' is acceleration, 'k' is Boltzmann's

constant and 'T' is temperature.  This is known as the Davies-Unruh effect.

[25,26]  Yet another factor which shows up in the ZPF spectrum of an

accelerated observer is found, via the equivalence principle, to reveal a deep

connection between zero-point energy and gravity along lines originally

proposed by Sakharov [27] (that gravity could be understood as an induced

effect brought about by changes in the quantum fluctuation energy of the vacuum

due to the presence of matter [17]).

Thus we see that, with its roots in relativity theory which banished the ether,

QED has in some sense come full circle to provide us with a model of an

energetic vacuum that once again constitutes a plenum rather than a void.

SOURCE OF ZERO-POINT ENERGY

The fact that the vacuum constitutes an energy reservoir leads naturally to the

question as to where the zero-point energy comes from, specifically, the vacuum

electromagnetic zero-point energy under discussion here.  (This is an

especially important issue if one considers the possibility of extracting such

energy for use.)  Nature provides us with but two alternatives:  existence by

fiat as part of the boundary conditions of the present universe (like, for

example, the 3 K cosmic background radiation left over from the Big Bang), or

generation by the (quantum fluctuation) motion of charged particles that

constitute matter.  This latter possibility was explored in a recent paper by

the author, with positive results.[23]

The argument goes as follows.  Given charged particles in quantum zero-point

motion throughout the universe, a 1/r^2 dependence of the radiation from such

motion, and an average volume distribution of such particles in spherical

shells about any given point that is proportional to the area of the shell

(that is,proportional to r^2), one could reasonably expect to find at any given

point a sum of contributions from the surrounding shells that yielded a high-

density radiation field.  (Recall a similar argument in astronomy associated

with Olbers' paradox.)  The high-density ZPF fields would appear to be just

such a field.

The details of the calculations examine the possibility that ZPF fields drive

particle motion, and that the sum of particle motions throughout the universe

in turn generates the ZPF fields, in the form of a self-regenerating

cosmological feedback cycle not unlike a cat chasing its own tail.  This self-

consistent field approach, carried out assuming inflationary cosmology, is

found to yield the correct frequency distribution and the correct order of

magnitude to match the known ZPF distribution, thus supporting the hypothesis

that the ZPF fields are dynamically generated.

As it turns out, there is an additional bonus from the calculations.  A derived

expression relating the zero-point energy density to such factors as the mass

density and size of the universe also yields a precise expression for an

observed 'cosmological coincidence' often discussed in the context of Dirac's

large-numbers hypothesis:  namely, that the electromagnetic-to-gravitational

force ratio between an electron and proton is equal to the ratio of the Hubble

distance to the size of the classical electron.  According to the relevant

calculations such a cosmological coincidence is seen to be a consequence of the

cosmologically-based ZPF-generation mechanism under consideration that serves

to link cosmological and atomic parameters.

The overall picture that emerges, then, is that the electromagnetic ZPF

spectrum is generated by the motion of charged particles throughout the

universe which are themselves undergoing ZPF-induced motion, in a kind of self-

regenerating grand ground state of the universe.  In contrast to other

particle-field interactions, the ZPF interaction constitutes an underlying,

stable 'bottom-rung' vacuum state that decays no further but reproduces itself

on a dynamic-generation basis.  In such terms it is possible to explicate on a

rational basis the observed presence of vacuum zero-point energy.

VACUUM ENERGY EXTRACTION?

As we have seen, the vacuum constitutes an extremely energetic physical state.

Nonetheless, it is a giant step to consider the possibility that vacuum energy

can be 'mined' for practical use.  To begin, without careful thought as to the

role that the vacuum plays in particle-vacuum interactions, it would only be

natural to assume that any attempt to extract energy from the vacuum might

somehow violate energy conservation laws or thermodynamic constraints (as in

misguided attempts to extract energy from a heat bath under equilibrium

conditions).  As we shall see, however, this is not quite the case.

The premier example for considering the possibility of extracting energy from

the vacuum has already appeared in the literature in a paper by R.L. Forward

entitled "Extraction of Electrical Energy From the Vacuum..."[28];  it is the

Casimir effect.  Let us examine carefully this ZPF-driven phenomenon.

With parallel, non-charged conducting plates set a distance D apart, only those

(electromagnetic) modes which satisfy the plate boundary conditions (vanishing

tangential electric field) are permitted to exist.  In the interior space this

constrains the modes to a discrete set of wavelengths for which an integer

number of half-wavelengths just spans the distance D (see Figure 3).  In

particular, no mode for which a half-wavelength is greater than D can fit;  as

a result, all longer-wavelength modes are excluded, since for these wavelengths

the pair of plates constitutes a cavity below cutoff.  The constraints for

modes exterior to the plates, on the other hand, are much less restrictive due

to the larger spaces involved.  Therefore, the number of viable modes exterior

is greater than that interior.  Since such modes, even in vacuum state, carry

energy and momentum, the radiation pressure inward overbalances that outward,

and detailed calculation shows that the plates are pushed together with a force

that varies as 1/D^4, viz,[10]

F/A = -(pi^2/240)(h*c/D^4)  newtons/m^2    (eqn. 2)

The associated attractive potential energy (Casimir energy) varies as 1/D^3,

U/A = -(pi^2/720)/(h*c/D^3)  joules/m^2    (eqn. 3)

As is always the case, bodies in an attractive potential, free to move, will do

so, and in this case the plates will move toward each other.  The conservation

of energy dictates that in this process potential energy is converted to some

other form, in this case the kinetic energy of motion.  When the plates finally

collide, the kinetic energy is then transformed into heat.  (The overall

process is essentially identical to the conversion of gravitational potential

energy into heat by an object that falls to the ground.)  Since in this case

the Casimir energy derives from the vacuum, the process constitutes the

conversion of vacuum energy into heat, and is no more mysterious than in the

analogous gravitational case.

In such fashion we see that the conversion of vacuum energy into heat, rather

than violating the conservation of energy, is in fact required by it.  And this

conversion can be traced microjoule by microjoule as modes (and their

corresponding zero-point energies) are eliminated by the shrinking separation

of the plates.  What takes getting used to conceptually is that the vacuum

state does not have a fixed energy value, but changes with boundary conditions.

In this case vacuum-plus-plates-far-apart is a higher energy state than vacuum-

plus-plates-close-together, and the combined system will decay from the higher-

energy state to the lower, in the process creating kinetic energy, then heat,

to conserve overall energy.  Similar vacuum-decay processes have been discussed

within the context of so-called charged vacuum states.[29]

With regard to extracting zero-point energy for use, in Forward's proposed

embodiment the two plates in a Casimir experiment are charged with the same-

sign charge (e.g., electrons).  At sufficiently small spacings the Coulomb

repulsion between the plates (which goes in an inverse square law 1/D^2 or

less, depending on spacing and geometry) can always be overcome by the stronger

1/D^4 attractive Casimir force.  The plates will therefore be drawn together in

a collapsing motion.  This confines the charge distribution to a smaller and

smaller volume and results in an increased electric field strength in the

vicinity of the plates.  In such fashion the zero-point energy (Casimir energy)

is transformed into stored Coulomb energy, which can then be extracted by a

variety of means.

Although demonstrating in principle the extraction of energy from the vacuum,

Forward's embodiment is admittedly impractical for significant, continuous

energy generation, for a number of reasons.  First and foremost is the fact

that the generator is a 'one-shot' device.  To recycle the generator one must

put as much energy into the device to return the plates to their original

separated positions as was obtained during the collapse phase, as would be

expected in any conservative potential.  As a result, given the losses in any

real system, not even 'break-even' operation can be achieved, let alone net

energy gain.

Let us carry this one step further, however.  If one could arrange to have an

inexhaustible supply of such devices, and if it took less energy to make each

device than was obtained from the Casimir-collapse process, and if the devices

were discarded after use rather than recycled, then one could envision the

conversion of vacuum energy to use with a net positive yield.  Although almost

certainly not achievable in terms of mechanical devices, a possible candidate

for exploitation along such lines would be the generation of a cold, dense,

non-neutral (charged) plasma in which charge condensation takes place not on

the basis of charged plates being drawn together, but on the basis of a Casimir

pinch effect.  (Casimir pinch effects have been explored in the literature, not

with regard to energy conversion, but in terms of semiclassical modelling of

charge confinement in elementary particles, hadron bag models, etc.[30])  Such

an approach would constitute a 'Casimir-fusion' process, which in its cycle of

operation would mimic the nuclear-fusion process.  It would begin, like its

nuclear counterpart, with an initial energy input into a plasma to overcome a

Coulomb barrier, followed by a condensation of charged particles drawn together

by a strong, short-range attractive potential (in this case a Casimir rather

than a nuclear potential), and with an accompanying energy release.  Should the

energy requirements for plasma formation, and electrical circuit and heat

losses be kept at a level below that required for break-even operation, then

net, useful energy could in principle be generated, as in the nuclear case.

Such a proposal is, of course, highly speculative at this point, and further

detailed analysis of the energetics involved may yet uncover some hidden flaw

in the concept.  Nonetheless, known to this author are programs in the United

States, the Soviet Union and other countries to explore just such an approach

on an experimental basis.

The above provides just one example of the type of concept that can be explored

with regard to possible vacuum energy extraction.  Other proposals for

extracting vacuum energy have been made as well,[31] covering the gamut from

the clearly unworkable to the intriguing.  To this author's way of thinking,

however, there is as yet neither clear-cut evidence of experimental success nor

an absolutely unimpeachable theoretical construct.  Nonetheless, it is only by

continued, careful consideration of such proposals that we can hope to resolve

the issue as to whether energy can be extracted from the vacuum, as part of a

generalized 'vacuum engineering' concept of the type suggested by Nobel

Laureate T.D. Lee.[32]  As a caution along the way, the prudent scientist,

while generally keeping an open mind as to the possibility of vacuum energy

extraction, must of course approach any particular device claim or theoretical

proposal with the utmost rigor with regard to verification and validation.

Can the energy crisis be solved by harnessing the energies of the zero-point

sea?  In the final analysis, given our relative ignorance at this point we must

of necessity fall back on a quote given by Podolny [33] when contemplating this

same issue.  "It would be just as presumptuous to deny the feasibility of

useful application as it would be irresponsible to guarantee such application."

Only the future can reveal whether a program to extract energy from the vacuum

will meet with success.

ACKNOWLEDGEMENTS

I wish to express my appreciation to G.W. Church, Jr., for helpful discussion

in the exploration of the concepts developed here.  I also wish to thank K.R.

Shoulders of Jupiter Technologies, Austin, Texas, and William L. Stoner, III,

of OmniTech International, Springdale, Virginia, for continuing impetus and

encouragement to explore these issues.

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-End of Paper-