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Breakthrough Propulsion Physics
Proposal Summaries

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An Experimental Test of a Dynamic Mach's Principle Prediction

Principal Investigator: John G. Cramer, University of Washington, Seattle, WA

(Text excerpted and adapted from proposal summary.)

Mach's Principle accounts for inertial reaction forces resulting from the gravitational attraction of all matter in the universe to an accelerating object. James Woodward of California State University at Fullerton has extended Sciama's 1953 demonstration that inertia can be understood as a gravitational effect in a linearized General Relativity framework. Woodward has shown that in addition to the acceleration dependant term that provides the basis for inertia, there is a time-dependent transient term. This term predicts that an object with a time-varying energy density will have a non-negligible variation in rest mass which depends on the second time-derivative of the energy.

Woodward has constructed an experiment which attempts to observe the predicted rest mass variations by vibrating a charging capacitor with a piezoelectric driver, and has reported measuring a mass variation in apparent qualitative confirmation of the predicted mass-variation effect. Results of these experiments, however, have been challenged in peer-reviewed literature due to the large number of uncontrolled variables in the methodology. In particular, it seems possible that the applied vibrations coupled with non-linear mechanical responses of the system might lead to false positive observations.

We propose to substitute rotation for vibration as the medium for accelerating the hypothetical varying mass. The centripetal acceleration of a charging capacitor produces a constant pseudo-force in the rest frame of the capacitor, and thus cannot couple in first order to dimensional changes of the capacitor that might arise from charging and discharging or to mechanical nonlinearities in the force measuring apparatus. We propose to create a rotating four-capacitor array with synchronized charging and discharging of the capacitors. If a mass variation is present, this should produce a constant unidirectional force. Any mechanical imbalance in the apparatus would tend not to yield a unidirectional force but rather a vibration, thus discriminating a real effect from system flaws.

Such a mass variation, even if it is small, has interesting implications for propulsion. Acceleration appropriately phased with the mass variations should produce a net unidirectional force relative to the surrounding mass of the universe. A spacecraft engine utilizing this principle would not require propellant, thus achieving the first mission of the Breakthrough Propulsion Physics program. If Woodward's effect is real, it is of the greatest importance to establish this fact. Therefore, a high priority should be to test the effect, preferably using an experimental design that avoids vibrations that might give rise to confusing background effects. The proposed verification of the Woodward effect needs only a modest investment in funding. However, if the Woodward effect is real, it has the potential to trigger enormous change in near-future spacecraft design and indeed to revolutionize the entire transportation industry.

Woodward, James F., "Measurements of a Machian Transient Mass Fluctuation," Foundations of Physics Letters, Vol. 4, No. 5, pp. 407-423, 1991.

The Use of Surfaces in Systems to Exploit Quantum Vacuum Energy: A Theoretical Study Using QED (Quantum Electrodynamics) Coupled with an Experimental Study Using MEMs (Microelectromechanical) Devices

Principle Investigator: Jordan Maclay, Quantum Fields LLC, Richland Center, WI

(Text excerpted and adapted from proposal summary.)

Quantum Electrodynamics (QED) is probably the best verified theory in physics. It makes some startling predictions about the importance of quantum fluctuations of the electromagnetic field in empty space. It predicts a near infinite vacuum energy density. Quantum fluctuations have been linked to particle mass, to spontaneous emission, to the speed of light, and to the topology of the universe. Since the presence of surfaces will change the energy density of the vacuum, surfaces can be used to alter parameters affected by vacuum fluctuations. The ability to alter these parameters could be of significant benefit to the BPP objectives. We will perform a theoretical investigation of the use of surfaces and cavity structures in order to alter vacuum energy. A microelectromechanical (MEMS) interferometric structure is planned to measure the index of refraction in a cavity, which will serve as a test of QED predictions.

The variations in vacuum energy produced by surfaces can also result in vacuum forces, such as the recently verified Casimir force between two parallel conducting plates. Very few other geometrical structures have been investigated, and our understanding of the role of surfaces in altering vacuum energy and generating vacuum forces is rudimentary. For rectangular cavities, forces are predicted on the walls that may be inward, outward, or zero, depending on the ratios of the sides. Such forces may be of use in operating MEMS devices, including resonant cavities. We propose to model and build a MEMS cavity structure, to verify the QED prediction of repulsive forces, and to study the properties of these cavities and the energy balance in a static and in a vibrating mode. When we have gained a greater understanding of cavities and vibrating structures, a second-generation MEMS structure will be designed, modeled, fabricated, and tested.

We will investigate the possibility of fluctuation-driven engines that operate between two regions of different energy density, in a similar manner to which heat engines operate between two heat reservoirs at different temperature. Two types of engine will be considered: one in which one set of surfaces moves relative to another, akin to an electric motor, and a second type in which a working fluid, perhaps consisting of atoms or electrons, passes between the two regions of different vacuum energy. We will develop several candidate structures for fluctuation engines and fabricate the most promising. In all theoretical and experimental work, care will be taken to understand energy balance requirements and conservation laws, and to determine what is possible and what is not. QED computations will be used as the guide.

This effort will answer many of the basic questions about the role of vacuum fluctuations, and lay a solid foundation of knowledge about vacuum energy, vacuum stresses and how to control them using surfaces and what their limitations are. Researchers will be able to build upon this knowledge to build more complex ideas and structures involving vacuum fluctuations.

Search for Effects of an Electrostatic Potential on Clocks in the Frame of Reference of a Charged Particle

Principal Investigator: Harry I. Ringermacher, General Electric Research and Development, Schenectady, NY

(Text excerpted and adapted from proposal summary.)

A new theory that self-consistently imbeds classical electrodynamics within the framework of non-Riemannian space-time, by way of introduction of an electrodynamic Torsion tensor into Einstein's equations, has been formulated and its field equations solved. The theory predicts that an intense, external electrostatic potential should measurably shift the internal clock of a charged particle analogously to the gravitational red shift. The internal clock refers to time as seen by a particle of charge-to-mass ratio, e/m, in its rest frame. We propose a nuclear magnetic resonance experiment to measure the influence of the electrostatic potential on the precession rate (clock) of a proton magnetic moment. The first of two definitive papers describing the theory has already been published [1]. Metric solutions of Einstein's field equations result in the correct electromagnetic potentials appearing in the metric tensor for several cases including spherical gravity plus electrostatic field, the line charge electric field, and the uniform magnetic field. The latter two solutions are exact. All of the solutions have been shown to satisfy a general equivalence principle including both attractive and repulsive forces resulting from two signs of charges.

Since the electromagnetic 4-vector potential (the scalar potential in g00) appears as the solution in the metric, much like the gravitational potential in the usual gravity theory, an experimental prediction is proposed that an electrostatic potential influences clocks in much the same way as gravitational potentials with one major difference: these solutions are in the frame of reference of the charged particle. Such a clock, which will be referred to as a charged clock, is arbitrary, much like a quantum phase, and will not influence measurable events. Only time differences could be measured. The application of nuclear magnetic resonance (NMR) offers an opportunity to synchronize charged clocks and subsequently read out changes arising from the application of intense electrostatic potentials during the NMR process. NMR is a natural way to read charged clocks since the NMR effect is itself induced in the rotating frame of the charged particle, in this case, a proton with a magnetic dipole moment (spin). The ideal effect, for a fully "supported" proton subjected to a l0-kV electric field, is expected to generate a frequency spectral line shift (equivalent to a shift in time) on the order of 6 ppm and broadening for a sharp proton resonance. This is easily measurable in a typical high resolution NMR spectrometer. The size of the actual measured effect will depend on the final choice of experimental conditions representing, as closely as possible, a "supported proton." A complementary NMR experiment would measure the effects of potential difference alone under zero field condition.

If this theory is proven, then there may exist solutions where electromagnetism can dynamically couple to space, time, and gravity, either explaining existing effects or predicting new ones. In particular, such solutions could be applied to the goal of creating propulsive effects.

I>Classical and Quantum Gravity, Vol. 11, pp. 2383-2394, 1994.

Exploration of Gravity Modification by Josephson Junction Effects in Magnetized High-Tc Superconducting Oxides

Principal Investigators: Glen A. Robertson and Ron R. Litchford, NASA Marshall Space Flight Center, Huntsville, AL

(Text excerpted and adapted from proposal summary)

In response to the propulsion challenges specified by NASA's Breakthrough Propulsion Physics (BPP) program, the NASA Marshall Space Flight Center proposes to empirically explore the possibility of inducing gravity modification through Josephson junction effects in magnetized, high-Tc superconducting oxides. Our technical goal is to critically test emerging physical concepts and provide rigorous empirical confirmation (or refutation) of anomalous effects related to the manipulation of gravity by magnetized type-II superconductors. Because the current empirical evidence for gravity modification is anecdotal, we propose, as a first step, to design, construct, and meticulously carry out a discriminating experiment. Our approach is unique in that we will construct an extremely sensitive torsional gravity balance to measure gravity modification effects by radio-frequency-pumped type-II superconductor test masses. Analysis indicates that an effective change in mass of less than 1 percent would be readily detectable by state-of-the-art differential capacitance transducers. The entire project is to be completed in 12 months.

If uncontested positive effects can be detected, it would seem to imply a fundamentally new method for creating motion without propellant. This goes directly to the heart of BPP goal 1 which has the stated aim of reducing or eliminating the need for mass ejection from spacecraft propulsion systems.

Detection of Superluminal propagation at low or near resonance frequencies and the dynamics of the Forerunners

Principle Investigator: Kevin Y. Malloy, University of New Mexico, Albuquerque, MN

(Text excerpted and adapted from proposal summary.)

In recent years, the subject of superluminal propagation has received much attention. A complete review of this field is provided in reference [1]. At the present, a body of experimental evidence [2-7] suggests the reality of superluminal group velocities for tunneling photons (and perhaps electrons); however, there is no universal agreement on the interpretation of these facts. In all of the above experiments, the magnitude of the incoming wave is attenuated upon tunneling and consequently the energy velocity remains subluminal. [8].

In principal, a rather more striking superluminal behavior can be exhibited in the case of inverted medium. Under special circumstances photons can travel through an inverted medium with phase, group, energy, and signal velocities all exceeding the velocity of the light in vacuum [1, 9]. This phenomenon can occur either at low frequencies or at frequencies close to resonance. While the low- frequency behavior is easier to understand (the index becomes less than 1), the higher frequency response can be understood in terms of tachyon-like excitation process, in which undamped atomic polarization waves are strongly coupled to electromagnetic waves. This phenomenon is different in nature from the previously studied tunneling effects and in principal can be observed over long distances. While the theoretical foundation for the above anomalous effect is well established [9], as to date, there has not been any experimental verification. We propose exploring the above possibility via experiments with inverted media such as fiber amplifiers or rubidium vapor. Since both the low frequency and the tachyonic propagation involves exchange of energy between the wave and matter resulting in superluminal energy velocities, it is perhaps necessary to redefine energy velocity such that this rather anomalous effect is properly explained [ 10].

It is believed that in all superluminal propagation (low frequency, tachyonic or tunneling), the very front of the optical or microwave signal shall remain luminal in order to properly address the requirements of the special relativity and causality. Therefore, a careful investigation of these early parts of the signal, so called "forerunners" is of tremendous importance in regard to propulsion "make-or-break" issues. The form of the forerunners is dictated by the details of the dispersion relation and the incoming wave. Since in our tunneling experiments and many others, the optical multi-layers, also known as one dimensional photonic crystals (1DPC), are used [11], it is natural that we investigate the dynamics of forerunners for this particular structure. In this proposal, we envision a theoretical formulation of the forerunner's field and the possible experimental detection of these fields for the case of 1DPCs. Clearly, a correct mathematical formulation of the forerunners and possible consequent detection of these disturbances strongly suggests that, regardless of superluminal observation of group, signal, or even energy velocity, the requirements of causality is fully observed, and no violation of principal axioms are allowed.

Although it is premature and non-scientific at present to suggest a detailed and direct connection between the proposed tasks and possible future BPP devices, the suggested tasks are in close correlation with the expressed desire of "conducting experiments or advancing theories that address critical unknowns, make-or-break issues or curious effects." In other words, while the proposed ideas are far from becoming breakthroughs in near future, they provide a starting point for scientifically assessing the ideas regarding the application of theses anomalous effects to propulsion physics.

  • [1] Chiao and Steinberg, Progress in Optics, 37, 345 (1997).
  • [2] Steinberg, Kwiat, and Chiao, Phys. Rev. Lett., 71, 708 (1993); Steinberg and Chiao, Phys. Rev. A., 51, 3525 (1995).
  • [3] Enders and Nimtz, J. Phys. I France, 2, 1693 (1992).
  • [4] Ranfagni, Fabeni, Pazzi, and Mugnai, Phys. Rev. E., 48, 1453 (1993); Mugnai, Ranfagni, and Ronchi, Phys. Lett. A., 247, 281 (1998).
  • [5] Spielmann, Szipocs, Stingl, and Krausz, Phys. Rev. Lett., 73, 2308 (1994).
  • [6] Mojahedi, Schamiloglu, Agi, and Malloy, submitted to Phys. Rev. E.
  • [7] Mojahedi and Malloy, to be published.
  • [8] Scalora, Dowling, Manka, Bowden, and Haus, Phys. Rev. A., 52, 726 (1995).
  • [9] Chiao, Phys. Rev. A., 48, R34 (1993); Chiao, Boyce, and Mitchell, Appl. Phys. B 60, 259 (1995); Chiao, Kozhekin, and Kurizki, Phys. Rev. Lett., 77, 1254 (1996); Morgan and Chiao, Am. J. Phys. 66, 14 (1998); Chiao, Population inversion and superluminality, in Amazing Light: a volume dedicated to Charles Hard Townes on his 80th birthday (Springer-Verlag, New York, 1996), p. 91.
  • [10] Diener, Phys. Lett. A., 235, 118 (1997).
  • [11] Yablonovitch, J. Opt. Soc. Am. B 10, 283 (1993).

Negative Energy for Hyper-fast Travel

Principal Investigator: Serguei Krasnikov, Independent researcher, Altamonte Springs, FL

(Text excerpted and adapted from proposal summary.)

It has been shown that the travel time for a spaceship can be reduced beyond the restrictions seemingly imposed by the light speed limit provided that the spaceship is able to curve spacetime in an appropriate way. It is most likely, however, that the matter required for such a process would be of a very specific nature ("exotic" matter). It has been conjectured that this fact can make circumventing the light barrier unphysical, since the required amount of exotic matter may turn out to be enormous.

The proposed research will determine whether this exotic matter is absolutely necessary to create the desired effects and whether the required amounts of this matter are indeed prohibitively great. The previously published suggestions for hyperfast travel will be compared to the most general case to assess the necessity of exotic matter. To this end the simplest mathematical case will be considered, for which the answer can be obtained within well-established methods of quantum field theory in a curved background without invoking additional hypotheses or approximations.


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