An Introduction to Zero-Point Energy

Quantum physics predicts the existence of an underlying sea of zero-point energy at every point in the universe. This is different from the cosmic microwave background and is also referred to as the electromagnetic quantum vacuum since it is the lowest state of otherwise empty space. This energy is so enormous that most physicists believe that even though zero-point energy seems to be an inescapable consequence of elementary quantum theory, it cannot be physically real, and so is subtracted away in calculations.

A minority of physicists accept it as real energy which we cannot directly sense since it is the same everywhere, even inside our bodies and measuring devices. From this perspective, the ordinary world of matter and energy is like a foam atop the quantum vacuum sea. It does not matter to a ship how deep the ocean is below it. If the zero-point energy is real, there is the possibility that it can be tapped as a source of power or be harnassed to generate a propulsive force for space travel.

The propellor or the jet engine of an aircraft push air backwards to propel the aircraft forward. A ship or boat propellor does the same thing with water. On Earth there is always air or water available to push against. But a rocket in space has nothing to push against, and so it needs to carry propellant to eject in place of air or water. The fundamental problem is that a deep space rocket would have to start out with all the propellant it will ever need. This quickly results in the need to carry more and more propellant just to propel the propellant. The breakthrough one wishes for deep space travel is to overcome the need to carry propellant at all. How can one generate a propulsive force without carrying and ejecting propellant?

There is a force associated with the electromagnetic quantum vacuum: the Casimir force. This force is an attraction between parallel metallic plates that has now been well measured and can be attributed to a minutely tiny imbalance in the zero-point energy in the cavity between versus the region outside the plates. This is not useful for propulsion since it symmetrically pulls on the plates. However if some asymmetric variation of the Casimir force could be identified one could in effect sail through space as if propelled by a kind of quantum fluctuation wind. This is pure speculation.

The other requirement for space travel is energy. A thought experiment published by physicist Robert Forward in 1984 demonstrated how the Casimir force could in principle be used to extract energy from the quantum vacuum (Phys. Rev. B, 30, 1700, 1984). Theoretical studies in the early 1990s (Phys. Rev. E, 48, 1562, 1993) verified that this was not contradictory to the laws of thermodynamics (since the zero-point energy is different from a thermal reservoir of heat). Unfortunately the Forward process cannot be cycled to yield a continuous extraction of energy. A Casimir engine would be one whose cylinders could only fire once, after which the engine become useless.

The basis of zero-point energy is the Heisenberg uncertainty principle, one of the fundamental laws of quantum physics. According to this principle, the more precisely one measures the position of a moving particle, such as an electron, the less exact the best possible measurement of momentum (mass times velocity) will be, and vice versa. The least possible uncertainty of position times momentum is specified by Planck's constant, h. A parallel uncertainty exists between measurements involving time and energy. This minimum uncertainty is not due to any correctable flaws in measurement, but rather reflects an intrinsic quantum fuzziness in the very nature of energy and matter.

A useful calculational tool in physics is the ideal harmonic oscillator: a hypothetical mass on a perfect spring moving back and forth. The Heisenberg uncertainty principle dictates that such an ideal harmonic oscillator -- one small enough to be subject to quantum laws -- can never come entirely to rest, since that would be a state of exactly zero energy, which is forbidden. In this case the average minimum energy is one-half h times the frequency, hf/2.

Radio waves, light, X-rays, and gamma rays are all forms of electromagnetic radiation. Classically, electromagnetic radiation can be pictured as waves flowing through space at the speed of light. The waves are not waves of anything substantive, but are in fact ripples in a state of a field. These waves do carry energy, and each wave has a specific direction, frequency and polarization state. This is called a "propagating mode of the electromagnetic field."

Each mode is subject to the Heisenberg uncertainty principle. To understand the meaning of this, the theory of electromagnetic radiation is quantized by treating each mode as an equivalent harmonic oscillator. From this analogy, every mode of the field must have hf/2 as its average minimum energy. That is a tiny amount of energy, but the number of modes is enormous, and indeed increases as the square of the frequency. The product of the tiny energy per mode times the huge spatial density of modes yields a very high theoretical energy density per cubic centimeter.

From this line of reasoning, quantum physics predicts that all of space must be filled with electromagnetic zero-point fluctuations (also called the zero-point field) creating a universal sea of zero-point energy. The density of this energy depends critically on where in frequency the zero-point fluctuations cease. Since space itself is thought to break up into a kind of quantum foam at a tiny distance scale called the Planck scale (10-33 cm), it is argued that the zero point fluctuations must cease at a corresponding Planck frequency (1043 Hz). If that is the case, the zero-point energy density would be 110 orders of magnitude greater than the radiant energy at the center of the Sun.

When a passenger in an airplane feels pushed against his seat as the airplane accelerates down the runway, or when a driver feels pushed to the left when her car makes a sharp turn to the right, what is doing the pushing? Since the time of Newton, this has been attributed to an innate property of matter called inertia. In 1994 a process was discovered whereby the zero-point fluctuations could be the source of the push one feels when changing speed or direction, both being forms of acceleration. The zero-point fluctuations could be the underlying cause of inertia. If that is the case, then we are actually sensing the zero-point energy with every move we make (see origin of inertia).

The principle of equivalence would require an analogous connection for gravitation. Einstein's general relativity successfully accounts for the motions of freely-falling objects on geodesics (the "shortest" distance between two points in curved spacetime), but does not provide a mechanism for generating a gravitational force for objects when they are forced to deviate from geodesic tracks. It has been found that an object undergoing acceleration or one held fixed in a gravitational field would experience the same kind of asymmetric pattern in the zero-point field giving rise to such a reaction force. The weight you measure on a scale would therefore be due to zero-point energy (see gravitation).

The possibility that electromagnetic zero-point energy may be involved in the production of inertial and gravitational forces opens the possibility that both inertia and gravitation might someday be controlled and manipulated. This could have a profound impact on propulsion and space travel.

How fields themselves work, and their relation to space, time, matter and energy, is the core subject of any unifield theory of physics. For a very good discussion, I recommend Brian Greene's "The Elegant Universe."

Ahh, this is the core of the matter. I have long been familiar with the graphic image of the magnetic field propagating through space as a sine wave, with the electric field propagating along the same line but polarized at a right angle to the magnetic field. What I was really wondering is, what exactly is the medium through which the wave propagates? Because, as we all know, our conventional understand of waves and energy require that you can't have a wave formed of nothing; the wave is a traveling oscillation jostling gas (or other) molecules around, in the case of sound; or a mobile inequity in the depth of a body of water, in the case of surf.

Apparently, with electromagnetic waves it's some sort of transmissible inequity allowing energy to be stored and released sequentially, in a process that propagates at rate c, in space itself.

I'll have to look up that book.

Apparently, with electromagnetic waves it's some sort of transmissible inequity allowing energy to be stored and released sequentially, in a process that propagates at rate c, in space itself.

Waves propagate by changes in the strength of fields over time. Fields change their strengths because of changes in the state(s) of the particles that generate the fields. To go deeper requires consideration of the meanings of concepts such as space-time, mass and energy. At that level, thought and communication become rather difficult, because analogies and metaphors with common experience become problematical, to say the least. Our culture, language, semantic models and perhaps even our very brains are not designed for it. We are lucky when we finds ways to model such things using some formalism (e.g., mathematical equations.) We are even luckier when the meaning of such formal models can be translated into common natural language.

Fields change their strengths because of changes in the state(s) of the particles that generate the fields.

Granted, a general discussion of field propagation is probably beyond me at this point. Failing that, could you name the particles relevant to propagating, say, a radio wave through vacuum?

He may be right but he did not do a good job of explaining why he's right

You are right, he did not.

the original statement was probably as correct as anything you, yourself, could say in a sentence or two.

As an engineer, and on a forum of nonengineers, I can live with approximate explanations. Were I a mathematician or talking to other techies, the distinction would be too great to blur over. The difference between applying an overt force vs. changing the momentum flux of a working medium are most definitely related, but not identical.

For example, a pure ramjet is an efficient air-breathing engine at high Mach. Ideally, it is an open cylinder (imagine a paper towel tube), that has burning fuel injected into the center of the cylinder. The problem with this design is it can't start from zero velocity, but if you could get the thing going fast to start with and then "turn on" the ramjet, it would work just fine. Clearly, the engine isn't "pushing" on the air flowing through this hollow tube. It is the burning fuel which raises the energy of the air in the tube, which makes it expand at higher velocity (momentum) out the back of the tube than it was entering at the front of the tube. It is, in essence a thermodynamic process, rather than a mechanical one, which is why the "pushing" analogy (a mechanical analogy) is not the best one to make.

are the devices emitting bosons, or are they merely propagating waves through a soup of bosons already in place?

It is not correct to consider the existence of fields, waves and particles as independent things. They form a unified whole, and work together as a system.

Force-transmitting particles are the wave quanta of their associated fields. In other words, waves propagate through a force field in discrete units of state change, and we call those wave-propagated quanta of field state change "particles." Force-transmitting particles exist because wave-propagated state change in fields is required to be quantized.

So the devices you mentioned are emitting vector bosons, not merely propagating waves through a soup of pre-existing particles.

where or when you went to school

Actually, I got a new Webster's since then and it still says the same. Nothing has changed, except a lot of people seem to be questioning authority these days.

Question Authority!

Saw this today on the back of a Datsun stationwagon; sticker looked new, in better shape than the rest of the car.

It is well documented that you are paid spammers using money from George Soros, etal, to convert us to a new world order with LESS freedom than we enjoy in America today. For the curious, Soros, Zimmer, Sperling, Lewis are all for a new world order, total gun control, elimination of constitutional rights just so they can make money by ruling us in a global manner.

You are a leftist democrat pushing for democratic capitalism with wealth redistribution via taxation. You are anti-Bush, anti-Republican, pro-Clinton, etc.

Question that someone is still driving a blue Datson B210.

Had a few dates with a lady who drove a B210, back when a B210 could be slightly used. Good memories. Don't know about the car, but she was nice.

I suspect there are more late-70s B210s on the road than there are early-80s Yugos. How do you make a Yugo go faster? Hitch it up to a tow truck!

You're correct... we seem to have broken loose from the comforting moorings of Newtonian physics.

I would guess, then, that bosons have no mass in the conventional sense.

So the devices you mentioned are emitting vector bosons, not merely propagating waves through a soup of pre-existing particles.

...implying, therefore, that the devices either turn electrons into vector bosons, or (more likely, as I see it) use the energy derived from an electrical charge differential to generate those vector bosons.

You know, I really should quit bugging you about this and read that book. Thus far, however, your information has been pretty darn fascinating.

Ask FR.

Does anyone know the meaning of the m in y = mx + b? The classic equation of a straight line function. Why m and not a or s? Slope is the usual term, although sometimes it is called something else. Why the letter m in most of the textbooks?

A guess might be m representing to metron from Greek, possibly something Pythagorean, meaning the measure, but that is just a guess. Did Isaac Newton originate the m, or is it older?

I would guess, then, that bosons have no mass in the conventional sense.

Vector bosons have no rest mass, but thanks to the famous e=mc², they do have relativistic mass.

An electron is a quantum of charge. When it oscillates, it creates waves in its associated electric field, resulting in the propagation of electromagnetic waves, which transmit energy that is quantized by the particle called a photon.

There was a perfectly simple point made:
-- If you are on the ground you can push against it to move.
-- If you are in the water you can push against it to move.
--- If you are in the air you can push against it to move.

--- If you are in space you can't push against it to move, --- you must eject something away from you.

81 -tpaine-

-- You cannot refute the above point, so you reply with a silly personal attack. Typical hot air.
119 -tpaine-
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It is well documented that you are paid spammers using money from George Soros, etal, to convert us to a new world order with LESS freedom than we enjoy in America today. For the curious, Soros, Zimmer, Sperling, Lewis are all for a new world order, total gun control, elimination of constitutional rights just so they can make money by ruling us in a global manner.

You are a leftist democrat pushing for democratic capitalism with wealth redistribution via taxation. You are anti-Bush, anti-Republican, pro-Clinton, etc. -cin-
____________________________________

Good grief, you have lost all grip on your sanity.

-- Please, - please, I ~beg~ you, -- try to establish that -- "It is well documented" that I am a "paid spammer using money from George Soros, etal," -- I need more belly laughs at your insane rantings.

Once again you have lost all control, 'cin'.
How many times have you been banned now for this type of behavior?
-- Really, lighten up. I've got more than five years of posts here that testify to my constitutional conservative credentials..

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