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Abstracts.Pdf Mach Effect Gravity Assist Drive- New Results Jim Woodward Abstract: New experimental results on the Mach effect gravitational assist drive, including the new duo-drive results. Movies of the runs taken will be shown. Below you see two 3 second pulses and a 10 second sweep over 24 kHz between them. We have two 19nF devices in parallel so we needed to incorporate a new tuning circuit. Paul March used circuit maker to design a resonant circuit with a 1:(1.5) step up transformer and a tuning coil of 515 μH. The plots represent 2 forward runs and 3 reverse run averages. Pitfalls of the Maxwellian approximation in GR Lance L. Williams For a talk, I would like to present on the Maxwellian approximation in GR. I would call it maybe "Maxwellian mirages in GR", or "Pitfalls of the Maxwellian approximation in GR." It involves considerations of gauge freedom, coordinate choices, and invariant potentials. Theoretical and numerical analysis of Mach-effect space-propulsion José J. Rodal, Ph.D. ABSTRACT: The theoretical foundations of Mach-effect space-propulsion are discussed. It is shown that the validity of Woodward's equation does not depend on the actual value of the mass-density of the universe. A covariant gravito- electro-magnetic analogy valid in the nonlinear domain of general relativity, as well as its non-local gravitational potentials are examined. Numerical comparisons between models and experimental observations are made. Quark Matter in the Solar System: A Resource for Advanced Propulsion? T. Marshall Eubanks!Space Initiatives, Inc., E-mail:[email protected] Submitted to the 2018 Estes Park Advanced Propulsion Workshop. Nuggets of condensed strange quark matter are a viable theory for macroscopic Dark Matter (DM), consistent with astrophysical constraints, despite their non- negligible cross sections, due to their very small cross section to mass ratios. This paper describes the observable consequences of the nugget theory developed by Ariel Zhitnitsky and his collegues, which predicts a stable nugget mass (MQ) 5 10 somewhere in the range 10 MQ 4 × 10 kg. DM is rarely considered to be important in the formation of the Solar system. However, under very general assumptions there would be “primordial capture” of DM due to gravitational potential changes during the collapse of the proto-planetary nebulae. For reasonable models of galactic DM velocity distributions and a giant molecular cloud mass comparable to the Orion-A star-forming region, the total amount of primordially captured DM for a Sun-type star would be ∼ 10−8 to 10−6 M⊙. Although almost any sort of DM would be subject to this process, the primordial capture of quark nuggets would lead to interesting consequences for the Solar System. In particular, masses in the range allowed by the Zhitnitsky theory could possibly resolve the “meter barrier” of planetary formation, serving as nucleation centers for proto-planetesimals and leading directly to a prediction that quark nuggets would reside today in the cores of the planets and asteroids. In the Zhitnitsky theory asteroids with radii 200 m would either not have a quark nugget core at all, or would be dominated by the mass of their strange matter core. Such “strange asteroids” would have unusually large masses and gravitational binding, but very small moment of inertia-mass ratios, leading to a prediction that some would sustain unusually fast rotation rates under Yarkovsky- O?Keefe- Radzievskii-Paddack (YORP) radiative torquing. The small Near Earth Objects (NEO) do indeed contain a population apparently consistent with these predictions, 10 12 implying, if these are gravi- tationally bound, that 10 MQ 10 kg, which overlaps with the stable mass range predicted by the Zhitnitsky theory. The interpretation of these asteroids as strange objects is complicated by the non-negligible cohesion expected from van deer Waals forces, and by the possibility that some such small bodies could be monolithic objects. At least for the fastest rotators it is hard, however, to see how either van der Waals forces, or a reasonable asteroid tensile strength, would be sufficient to pro- tect these bodies against rotational disruption without some additional binding mechanism, supporting (but not proving) the strange asteroid hypothesis. 1 The discovery of even a single quark nugget in the Solar System would of course be of immense scientific value. The Zhitnitsky theory is likely to be confirmed or denied as a consequence of the exploration and mining of NEO, as the existence of a quark core should be evident to in situ spacecraft examination. A completely independent way to search for quark matter is through neutrino radiography of the Earth’s core; as quark matter is opaque to the few GeV neutrinos currently used in long baseline neutrino experiments, a beam passed directly through the center of the Earth’s core would be absorbed by any quark matter there, but not by the ordinary matter of the core. The existing long baseline experiments possess sufficient sensitivity to perform this experiment, assuming they were suitably relocated. 2 Time Varying Chameleon Fields, Propagating Scalar Waves and Advanced Propulsion T. Marshall Eubanks Space Initiatives, Inc., E-mail:[email protected] Submitted to the 2018 Estes Park Advanced Propulsion Workshop The discovery of the accelerating expansion of the universe has led to a renewed interest in modifications of General Relativity. In particular, the addition of a scalar field (or fields) with energies comparable to the cosmo- logical constant could potentially provide a cosmologically significant “dark energy” component to gravity (1, 2). However, massless (Jordan-Brans-Dicke) scalar fields are subject to stringent constraints from laboratory and solar system tests of gravity and of the principle of equivalence (3). These tests require massless scalar fields to be much weaker than gravity, and thus unable to provide cosmologically significant corrections to standard gravity on any size scale. Chameleon fields are massive self-interacting scalar fields whose effective mass depends on the density of the surrounding normal matter; for sufficiently large and dense bodies in vacuum chameleon fields are restricted to a thin surface layer, greatly reducing the chameleon forces from such objects and allowing chameleon fields to evade the stringent constraints from laboratory and solar system tests while remaining dynamically important on galactic and intergalactic scales (2, 4, 5). For a laboratory sized or larger baryonic object in vacuum the thin chameleon surface layer will act in many ways like a surface electrical charge on a conductor (6). A time-varying chameleon field follows a Klein-Gordon equation for a massive scalar field with the resulting group velocity, vc, being (7) v 1 g = (1) c m2 1 + eff q k2 in natural units, where meff is the effective chameleon particle mass and the Planck constant and the speed of light are set to unity. Define Reff to be the Compton radius of meff ; this parameter sets the scale constant of the chameleon Yukawa potential and is constrained experimentally to be . 1 µm in baryonic matter (8). At the surface of a laboratory-sized mass of dimension R therefore v R g ∝ eff ≪ 1. (2) c R while in vacuum Equation 2 is inappropriate and vg ∼ c. Vibrations of a surface with a thin chameleon field in vacuum will generate propagating scalar waves, similar to the generation of waves from a moving surface charge in electromagnetism, although scalar waves will also support monopole radiation. The coupling between chameleon and matter fields thus implies that a non-relativistically vibrating mass in vacuum can be much more efficient at generating scalar radiation than at generating tensor gravitational waves; scalar wave generation will be most efficient when the size of the object is comparable to the crossing time of the 2 scalar waves. A laboratory mass with R ∼ 0.1 m will have a crossing time, R / vg ∼ R / (c Reff ), . 30 µs, and thus would generate scalar radiation most effectively at frequencies of order 30 kHz. Scalar radiation can transfer energy and momentum through vacuum, and thus could be used for propulsion in deep space. The effects described in this paper would not be evident in the numerous static or very low frequency 1 tests for a fifth force, and there are at present very few limits on frequency-dependent violations of the weak Equivalence Principle. However, it would be straightforward to search for this radiation with existing laboratory techniques, and it is possible it has been detected in work aimed at verifying Mach effect thrusters. References 1. P. J. Peebles and B. Ratra. The cosmological constant and dark energy. Reviews of Modern Physics, 75:559– 606, April 2003. 2. J. Khoury and A. Weltman. Chameleon Fields: Awaiting Surprises for Tests of Gravity in Space. Phys. Rev. Lett., 93(17):171104, October 2004. 3. C. M. Will. The Confrontation between General Relativity and Experiment. Living Reviews in Relativity, 17:4, June 2014. 4. J. Khoury and A. Weltman. Chameleon cosmology. Phys. Rev. D, 69(4):044026, February 2004. 5. C. Burrage and J. Sakstein. Tests of Chameleon Gravity. ArXiv e-prints, September 2017. 6. C. Burrage, E. J. Copeland, A. Moss, and J. A. Stevenson. The shape dependence of chameleon screening. J. Cosmology and Astroparticle Physics, 1:056, January 2018. 7. J. Ø. Lindroos, C. Llinares, and D. F. Mota. Wave propagation in modified gravity. Phys. Rev. D, 93(4):044050, February 2016. 8. J. Sakstein. Tests of gravity with future space-based experiments. Phys. Rev. D, 97(6):064028, March 2018. 2 Simulating and Testing Propulsion Devices on a Low-Thrust Torsion Pendulum Jamie Ciomperlik This presentation will focus on how a low-thrust torsional pendulum was fabricated, work with testing speculative propulsion devices, and how that lead to simulations and tests involving mechanically oscillating devices.
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