**THE ABRAHAM FORCE**

**A mechanical force of electromagnetic origin**

Experiments have been reported which verified that at low frequencies a time-varying polarisation P in a dielectric, if taking place in a magnetic field H, results in a **mechanical force.** This force is not predicted by the Minkowski energy-momentum tensor, but the Abraham form of that tensor gives a force density in an homogeneous isotropic body, usually called **the Abraham force.**

## The **Abraham force** constitutes the physical basis for explaining the **Biefeld-Brown effect**.

The Quantum Antigravity Space Propulsion is a type of **propellantless propulsion** that essentially stems from the Abraham force (see more below) —** a mechanical force of electromagnetic origin** — and from the method of its amplification. It is capable, in principle, of propelling a spacecraft to near the speed of Light velocities.

The complete mathematical description of **quantum antigravity** will slowly come later in due time, in a manner similar to Faraday-Maxwell developments. After all, Thomas Edison didn’t need all the math of quantum mechanics, or of Einstein’s photoelectric effect, or of de Broglie’s wave–particle duality to make his lightbulb work.

For an interplanetary spaceship, equipped with the Quantum Antigravity Space Drive, to be accelerated to near the speed of Light velocity, it needs to be powered. Solar power is good enough for slow orbital maneuvers. The Quantum Antigravity Space Drive could be powered by a thorium reactor, by a molten salt reactor, by a helium-3 reactor, by a **Wendelstein stellarator,** or by Taylor Wilson’s **fusion reactor,** in addition to a conventional nuclear reactor. All US Navy aircraft carriers and submarines built since 1975 are nuclear-powered. Some of them have up to 4 nuclear reactors on board. Since the last conventional aircraft carrier USS Kitty Hawk was decommissioned in May 2009, there have been only nuclear-powered aircraft carriers and submarines in the US Navy.

### Observation of the intrinsic Abraham force in time-varying magnetic and electric fields

The experimental observation of the Abraham force induced by an oscillating electric field and a static magnetic field was reported by James and by Walker et al in solid dielectrics, and recently by Rikken and Van Tiggelen in gases. These observations clearly invalidated the Minkowski version, although modifications of the Minkowski energy-momentum tensor have been proposed to make it consistent with these results. However, the Abraham force due to an oscillating magnetic field and a static electric field has so far never been observed and was even reported unobservable in a specifically designed experiment.

The Abraham force exerted by a time-dependent electromagnetic field on neutral, polarizable matter has two contributions. The one induced by a time-varying magnetic field and a static electric field is reported here for the first time. We discuss our results in the context of the radiative momentum in matter.

### ON THE **FEIGEL EFFECT** — EXTRACTION OF MOMENTUM FROM VACUUM

The Green-function formalism for the electromagnetic field in a magnetoelectric (ME) medium is constructed, as a generalization of conventional Casimir theory. It is shown how the formalism predicts electromagnetic momentum to be extracted from the vacuum field, just analogous to how energy is extracted in the Casimir case. The possibility of extracting momentum from vacuum was discussed recently by Prof. Alexander Feigel. By contrast to **Feigel’s approach,** we assume that the ME coupling occurs naturally, rather than being produced by external strong fields. We also find the same effect qualitatively via an other route, by considering one single electromagnetic mode.

In the case of high frequency fields, in particular optical fields, the Minkowski theory appears to be both simple and capable of describing all experiments. However, at low frequencies where the effect of the oscillations are themselves observable – notably in the Walker-Lahoz experiment – the experiments agree not with the Minkowski but rather with the Abraham force, at these frequencies.

Before leaving this idea, let us however note the following point: Assume that strong crossed fields E and H are applied between the conducting plates. Then, during the time when the external fields increase in strength, there acts an Abraham force in the fluid in the interior. Integrating over time, we see that the following mechanical momentum density is imparted to the fluid. This is the dominant momentum given to the fluid between the plates. In addition comes the momentum transferred from the wave modes. The momentum is actually very similar to the momentum, or more strictly to the angular momentum, transferred to the suspended dielectric cylindrical shell in the Walker-Lahoz experiment in ordinary electrodynamics.

### A new form of the energy-momentum tensor of the interaction of an electromagnetic field with a non-conducting medium

Wave equation for momentum density describes simultaneous transfer of momentum and angular momentum regardless of radiation polarization. From the tensor follow the balance equations of the electromagnetic forces for the momentum density in a continuous medium, and lead to the conclusion about the equality and mutual complementation of Minkowski’s and Abraham’s forms of momentum density. It is shown that the Abraham force exists only in the medium where the vectors D and E, H and B, are not colinear.

# A Blueprint for a Quantum Propulsion Machine

The quantum vacuum has fascinated physicists ever since Hendrik Casimir and Dirk Polder suggested in 1948 that it would exert a force on a pair of narrowly separated conducting plates. Their idea was eventually confirmed when the force was measured in 1997. Just how to exploit this force is still not clear, however.

In recent years, a new way of thinking about the quantum vacuum has emerged which has vastly more potential. And today, one physicist describes how it could be used to create propulsion.

Before we discuss that, let’s track back a little. According to quantum mechanics, any vacuum will be filled with electromagnetic waves leaping in and out of existence. It turns out that these waves can have various measurable effects, such as the Casimir-Polder force.

The new approach focuses on the momentum associated with these electromagnetic fields rather than the force they exert. The question is whether it is possible to modify this momentum because, if you can, you should receive an equal and opposite kick. **That’s what rocket scientists call propulsion.**

Today, Prof. Alexander Feigel at the Soreq Nuclear Research Center, a government lab in Yavne Israel, suggests an **entirely new way to modify the momentum of the quantum vacuum and how this can be exploited to generate propulsion. **Feigel’s approach combines two well-established ideas.

The first is the Lorentz force experienced by a charged particle in electric and magnetic fields that are crossed. The second is **the magneto-electric effect, the phenomenon in which an external magnetic field induces a polarised internal electric field in certain materials, and vice versa.**

The question that Feigel asks is in what circumstances the electromagnetic fields in a quantum vacuum can exert a Lorentz force. The answer is that **the quantum vacuum constantly interacts with magneto-electric materials generating Lorentz forces. Most of the time these forces sum to zero.**

However, Feigel says there are four cases in which the forces do not sum to zero. Two of these are already known, for example confining the quantum field between two plates, which excludes longer wavelength waves.

But Feigel says the two others offer entirely new ways to exploit the quantum vacuum using magneto-electric nanoparticles to interact with the electromagnetic fields it contains.

The first method is to rapidly aggregate a number of magneto-electric nanoparticles, a process which influences the boundary conditions for higher frequency electromagnetic waves, generating a force.

### The second one, is to **simply rotate, like a gyro, **a group of magneto-electric nanoparticles, which also generates a Lorentz force.

Either way, the result is a change in velocity. As Feigel puts it: *“mechanical action of quantum vacuum on magneto-electric objects may be observable and have a significant value.”*

**The beauty of Feigel’s idea is that it can be easily tested.** He suggests building an addressable array of magneto-electric nanoparticles, perhaps made of a material such as FeGaO3 which has a magneto-electric constant of 10^-4 in a weak magnetic field.

These nanoparticles **simply have to be rotated** in the required way to generate a force. Feigel calls it a magneto-electric quantum wheel.

Of course, nobody is getting a free lunch here. ** “Although the proposed engine will consume energy for manipulation of the particles, the propulsion will occur without any loss of mass,”** says Feigel. He even suggests, with masterful understatement, that this might have practical implications.