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Original titles, attribution, publication details and summaries in the selected language.
Published entries: 206
Matching entries: 206. Showing 76–100 of 206.
Paper · 2024
Gauge invariance of the Aharonov-Bohm effect in a quantum electrodynamics framework
- Pablo L. Saldanha(Author)
Pablo Saldanha demonstrates that the Aharonov-Bohm effect is gauge invariant when the electromagnetic field is treated quantum mechanically. He solves exactly, in the Lorenz gauge, for the ground energy of the quantum field interacting with the classical charges and currents that source the potentials. First-order perturbation theory then gives the extra energy from a charged quantum particle, which depends on its path through an interferometer and so produces the Aharonov-Bohm phase difference. The phase difference is shown to be gauge invariant for the magnetic, electric and recently proposed electrodynamic versions of the effect. For open paths the phase could depend on the gauge, reinforcing that it is measurable only around closed paths.
Paper · 2003
Gravitomagnetic field of a rotating superconductor and of a rotating superfluid
- M. Tajmar(Author)
- C.J. de Matos(Author)
Martin Tajmar and Clovis de Matos quantise an extended canonical momentum that includes gravitational drag, and apply it to rotating ring-shaped superconductors and superfluids. The starting point is the Barnett effect, in which rotation magnetises a material, together with its gravitational analogue in weak-field general relativity. Measurements of magnetic flux in rotating superconductors disagree with predictions made without a gravitomagnetic term, and the authors ask how much of that gap the gravitomagnetic term explains. For rotating neutral superfluids, the drag effects implied by the superconductor data would still sit within current experimental noise. They propose measuring the torque such a field would exert on a spinning gyroscope, an experiment not yet done.
Paper · 2005
Gravitomagnetic London moment and the graviton mass inside a superconductor
- C.J. de Matos(Author)
- M. Tajmar(Author)
Clovis de Matos and Martin Tajmar use the Proca form of electromagnetism and gravitoelectromagnetism to derive the magnetic and gravitomagnetic properties of a rotating superconductor. A superconductor expels magnetic fields and, when rotated, produces a magnetic field called the London moment. Both perfect diamagnetism and the London moment follow from the photon acquiring mass inside the superconductor. By analogy, their proposal to resolve the Cooper pair mass anomaly reported by Tate is explained by a graviton mass inside the superconductor different from its cosmological value. For niobium the required graviton mass is about 10^-55 kg, 14 orders of magnitude above the free-space limit, just as the photon mass is greatly raised inside a superconductor by the Higgs mechanism.
Paper · 2011
Gravity Probe B: Final Results of a Space Experiment to Test General Relativity
- C. W. F. Everitt(Author)
- D. B. DeBra(Author)
- B. W. Parkinson(Author)
- J. P. Turneaure(Author)
- J. W. Conklin(Author)
- M. I. Heifetz(Author)
- G. M. Keiser(Author)
- A. S. Silbergleit(Author)
- T. Holmes(Author)
- J. Kolodziejczak(Author)
- M. Al-Meshari(Author)
- J. C. Mester(Author)
- B. Muhlfelder(Author)
- V. Solomonik(Author)
- K. Stahl(Author)
- P. Worden(Author)
- W. Bencze(Author)
- S. Buchman(Author)
- B. Clarke(Author)
- A. Al-Jadaan(Author)
- H. Al-Jibreen(Author)
- J. Li(Author)
- J. A. Lipa(Author)
- J. M. Lockhart(Author)
- B. Al-Suwaidan(Author)
- M. Taber(Author)
- S. Wang(Author)
Everitt and colleagues report Gravity Probe B’s measurements of geodetic precession and frame dragging using four cryogenic gyroscopes in a 642 km polar Earth orbit. Their joint analysis gives drift rates of −6601.8 ± 18.3 and −37.2 ± 7.2 milliarcseconds per year, respectively, compared with general relativity’s predictions of −6606.1 and −39.2. The uncertainties combine statistical and systematic contributions. Superconducting readout tracked the gyroscopes relative to the guide star IM Pegasi during eleven months of science observations. Unexpected electrostatic patch torques and evolving rotor motion required calibration and trapped-flux mapping. Independent gyroscope analyses and a second geometric method provided cross-checks, yielding reported accuracies of 0.28% for the geodetic effect and 19% for frame dragging.
Paper · 2010
Hawking Radiation from Ultrashort Laser Pulse Filaments
- F. Belgiorno(Author)
- S. L. Cacciatori(Author)
- M. Clerici(Author)
- V. Gorini(Author)
- G. Ortenzi(Author)
- L. Rizzi(Author)
- E. Rubino(Author)
- V. G. Sala(Author)
- D. Faccio(Author)
Belgiorno, Cacciatori, Clerici, Gorini, Ortenzi, Rizzi and colleagues test the prediction that event horizons, real or analogue, excite the quantum vacuum and emit Hawking radiation. They use ultrashort laser pulse filaments, intense pulses in a transparent Kerr medium that travel apparently without diffraction. The filament creates a travelling refractive index perturbation in fused silica glass that acts as an analogue event horizon. Photons emitted at 90 degrees to the beam are collected and their spectra recorded. They observe spontaneous photon emission with the characteristics of Hawking radiation, distinct from other known emission mechanisms, confirming theoretical predictions.
patent · 2019
High frequency gravitational wave generator
- Salvatore Cezar Pais(Author)
Salvatore Cezar Pais’s patent proposes a gravitational-wave generator built around a gas-filled shell and two internal acoustic resonators. Microwaves vibrate the charged outer shell, while sound drives charged cavity surfaces to produce a second electromagnetic field. The proposed conversion mechanism invokes the Gertsenshtein effect, with one electromagnetic field propagating through another. Counter-rotating cavities provide mechanical stability; the claims specify inert gas and asymmetric wedge-shaped resonators. The description predicts gravitational-wave power around 10¹⁰ watts using an assumed electromagnetic flux around 10³³ watts per square metre and magnetic fields around 10¹⁰ tesla. Its proposed room-temperature superconducting wiring uses a metal-coated insulating core exposed to abrupt electromagnetic pulses, making the wiring treatment another substantive part of the device concept.
Paper · 2021
High-accuracy thrust measurements of the EMDrive and elimination of false-positive effects
- M. Tajmar(Author)
- O. Neunzig(Author)
- M. Weikert(Author)
M. Tajmar, O. Neunzig and M. Weikert test the EMDrive, a proposed propellantless thruster in which microwaves in a closed tapered cavity would produce at least 1 mN/kW of thrust. Heat, mechanical load and large currents can create artefacts that look like thrust. They built an inverted counterbalanced double pendulum balance that removes most thermal drift, and ran the device on its own battery pack to avoid feedthrough interactions. Across a wide frequency band with several resonances and modes they found no thrust, limiting any anomalous thrust to below the force of classical radiation for the same power. The result sets strong limits for every proposed theory and rules out earlier test results by at least two orders of magnitude.
Paper · 1998
Hyperfast Interstellar Travel in General Relativity
- S. V. Krasnikov(Author)
S. V. Krasnikov asks whether a traveller who can partly control spacetime geometry could reach a distant object and return sooner than light would. The stakes are distance: about 200 parsecs to Polaris, 500 to Deneb and around 10 kiloparsecs to the galactic centre. Under reasonable assumptions in globally hyperbolic spacetimes, the outbound trip itself cannot be sped up. Yet an arbitrarily long round trip may take an arbitrarily short time as seen from Earth. The key difference lies in the return leg, since devices placed along the route in advance can reshape spacetime so the traveller comes back early.
Paper · 2024
Impedance Spectroscopy Distinguishes Active ZrO2-PdNiD NANOR-type LANR Components
- Mitchell Swartz(Author)
Mitchell Swartz uses impedance, or dielectric, spectroscopy, a nondestructive way to measure how the electrical properties of lattice-assisted nuclear reaction materials change with frequency. An applied field polarises the material, and the task is to separate that response into the mechanisms that contribute to it. He examined previously active, dry, preloaded NANOR-type components made of ZrO2-PdD and ZrO2-PdNiD from about 10^4 Hz to about 2 GHz. Bode, Cole-Cole, Nyquist and Smith-chart plots show clear, distinguishable differences from conventional materials and ohmic controls. Active materials have highly unusual transconduction while producing excess heat, and dry preloaded samples can suffer avalanche breakdown that ends that heat.
Paper · 1994
Inertia as a zero-point-field Lorentz force
- Bernhard Haisch(Author)
- Alfonso Rueda(Author)
- H. E. Puthoff(Author)
Haisch, Rueda and Puthoff propose that inertia, the resistance of matter to acceleration, arises from interactions with electromagnetic vacuum fluctuations. Their 1994 model represents matter through hypothetical charged constituents that oscillate like tiny springs. They calculate the magnetic part of the Lorentz force on these constituents during constant proper acceleration (measured in the particle’s momentary rest frame), averaging over the fluctuating field. The resulting force is proportional to acceleration, with its proportionality coefficient interpreted as inertial mass. Its magnitude depends on an unspecified internal mass and a high-frequency interaction limit set by the constituents’ assumed Planck-scale size. This limit restricts the response of matter, not the vacuum spectrum itself. In the final force expression, the authors select the sign that opposes acceleration, consistent with the resistance they seek to explain.
Paper · 1998
Inertia as reaction of the vacuum to accelerated motion
- Alfonso Rueda(Author)
- Bernhard Haisch(Author)
Rueda and Haisch propose that part of inertia, the resistance to acceleration, could arise from interaction with the electromagnetic vacuum. Their calculation describes an accelerating object encountering a flow of momentum in zero-point radiation, the background fields used in their model. They interpret absorption or scattering of that radiation as a force opposing acceleration. The proposed mass contribution depends on the object’s volume and the fraction of radiation interacting with it at each frequency. That fraction is assumed to decrease at high frequencies, limiting the contribution of those frequencies. The calculation covers forces along the direction of motion. The microscopic interaction remains unspecified, and the authors leave a quantum derivation and the connection to general relativity for further work.
Paper · 2022
Interaction Between Macroscopic Quantum Systems and Gravity
- A. Gallerati(Author)
- G. Modanese(Author)
- G.A. Ummarino(Author)
Gallerati, Modanese and Ummarino review experiments and theory on how gravity may interact with superconductors and other macroscopic quantum states. Their focus is whether coherent quantum macrosystems can locally alter the gravitational field around them. The question dates to the 1960s, when physicists first asked whether superconductors could serve as sensitive gravity probes. Podkletnov's weight anomaly experiments with large YBCO superconductor disks remain neither confirmed nor disproved, and settling them would need substantial research investment. They also cover superconducting gravitational detectors and the possible backreaction of a superfluid on the surrounding gravitational field, still far from fully understood.
Paper · 2016
Interaction of gravitational waves with superconductors
- N. A. Inan(Author)
- J. J. Thompson(Author)
- R. Y. Chiao(Author)
Inan, Thompson and Chiao apply the Helmholtz decomposition to linearised general relativity to get a gauge-invariant description of gravitational waves in matter. A London-like equation describes gravitational waves entering a superconductor, and in the static limit the magnetic-like gravitational field is expelled, a gravitational Meissner-like effect. The Cooper pair density follows a Ginzburg-Landau free energy in curved spacetime, while the ionic lattice is modelled as quantum harmonic oscillators coupled to the gravitational wave. Because the wave modulates the zero-point energy of the lattice phonons, the model predicts a possible dynamical Casimir effect. The Cooper pairs respond far less than the ionic lattice, which predicts a charge separation in the superconductor driven by the gravitational wave.
Paper · 2021
Introducing physical warp drives
- Alexey Bobrick(Author)
- Gianni Martire(Author)
Bobrick and Martire model warp spacetimes as moving shells surrounding a flat passenger region, rather than as self-propelling engines. Their 2021 paper develops spherical configurations with positive energy at speeds below light, allowing gravity outside the shell and slower clocks inside relative to distant observers moving with it. They also explore changes to shape, interior volume and clock rates in other geometries. Flattening an Alcubierre configuration reduces its calculated negative-energy requirement, but the superluminal examples still violate the averaged null energy condition, a restriction on energy along light rays. Even their extremely thin examples that meet selected quantum inequalities retain this problem. Changing a shell’s velocity requires propulsion; a stationary geometry alone supplies no acceleration mechanism.
Paper · 2018
Isotopic and Elemental Composition of Substance in Nickel-Hydrogen Heat Generators
- K. A. Alabin(Author)
- S. N. Andreev(Author)
- A. G. Sobolev(Author)
- S. N. Zabavin(Author)
- A. G. Parkhomov(Author)
- T. R. Timerbulatov(Author)
Alabin, Andreev, Sobolev, Zabavin, Parkhomov and Timerbulatov analyse the isotopes and elements in fuel and nearby material from nickel-hydrogen reactors, before and after runs with up to 790 MJ of excess energy. In such reactors the excess heat far exceeds what chemistry allows and is comparable to nuclear energy release, without harmful radiation or radioactivity. Four reactors of different designs, with excess energy from 100 to 790 MJ, were examined, including the substance accumulating in the reactor cavity. Nickel and lithium isotopes showed no significant change, except in the fuel analysis of the AP2 reactor at Uppsala University in Sweden. Concentrations of several impurity nuclides rose significantly, both in the fuel and in structural parts next to the active zones.
talk · 2020
Lattice Confinement Fusion (LCF) Overview
- L Forsley(Author)
- T Benyo(Author)
- B Steinetz(Author)
- V Pines(Author)
- M Pines(Author)
- A Chait(Author)
- L Dudzinski(Author)
- M Forsbacka(Author)
- R Litchford(Author)
This NASA Glenn overview presents an advanced energy conversion project whose goal is power and energy sources for long-duration deep space missions. The team reports demonstrating bremsstrahlung photoneutron initiated fusion in what they describe as a globally cold, locally hot environment. They state that the process is repeatable and works with different lattice materials holding the deuteron fuel. Their calculations indicate that electron screening increases localized fusion rates in dense fuel and increases large angle scattering between charged particles, enhancing quantum tunneling. Predicted fusion rates are consistent with the observed neutron flux, and the work appeared as two papers in Physical Review C.
Report · 2024
Lattice Confinement Fusion (LCF) Technology Utilized By Astral Systems Ltd
- Theresa L Benyo(Author)
- Lawrence Forsley(Author)
Benyo and Forsley describe lattice confinement fusion, a method developed by a Glenn Research Center team that accomplishes fusion reactions in a metal solid. Deuterium fuel is confined to the space between metal atoms, and with electrons in the lattice and a trigger such as a gamma beam, fusion reactions are produced. They note that this fusion occurs in a lattice at ambient temperature. Astral Systems reports boosting deuterium fusion neutron output by at least 50 times compared to a commercially available neutron generator predecessor. The company reports that 99 percent of the fusion reactions are produced by lattice confinement fusion within its electrostatic confinement device, and its operating prototype fits on a desktop.
talk · 2024
Lattice Confinement Fusion-Fast-Fission
- Lawrence P Forsley(Author)
- Pamela A Mosier-Boss(Author)
- Theresa L Benyo(Author)
Forsley, Mosier-Boss and Benyo present lattice confinement fusion, the fusion of hydrogen isotopes into helium without tokamak magnets or laser power supplies. The nuclear fuel is confined and triggered within the lattice, and the nuclear reactions are enhanced by electron screening. They describe the process as locally hot but globally cold, and note that NASA published results in Physical Review C. In the hybrid fast-fission reaction, fusion neutrons fission uranium, spent fuel rods or thorium, which the authors present as cleaner fission with no enriched uranium. The applications they list run from low Earth orbit and deep space power to terrestrial use, and the approach was commercialized in 2024 to produce medical radioisotopes.
Paper · 2022
Lattice Energy Converter
- F.E. Gordon(Author)
- H.J. Whitehouse(Author)
F. E. Gordon and H. J. Whitehouse report Lattice Energy Converters that start on their own and sustain a voltage and current for extended periods. The converter turns internal energy of a lattice such as palladium, or of hydrogen or deuterium held in it, into ionising radiation and electrical energy. Voltage and current rise with temperature, and the output resembles a nuclear battery's without any radioactive material. Producing the measured voltage and current would take the equivalent of several curies of ionising radiation. Two individuals have replicated the results, and a gas conduction model with drift and diffusion terms explains the unusual current-voltage curves.
Paper · 2022
Lattice Energy Converter II: Iron Hydrogen Host Material
- F.E. Gordon(Author)
- H.J. Whitehouse(Author)
Gordon and Whitehouse earlier reported a Lattice Energy Converter whose codeposited palladium-hydrogen electrode produced spontaneous, sustained electrical energy attributed to ionising radiation. Here an iron-hydrogen electrode, codeposited from aqueous iron chloride, shows the same spontaneous, sustained electrical output and ionising radiation, and these results have been replicated. Iron was a natural candidate: at room temperature hydrogen diffuses about two orders of magnitude faster in iron than in palladium. They show conduction in the converter differs from ordinary gas conduction, because its source is radiation produced within the hydrogen-loaded host material.
talk · 2023
LENR Products: Lattice Confinement Fusion (LCF), Fission, or Both?
- Theresa L. Benyo(Author)
- Pamela Mosier-Boss(Author)
- Lawrence Forsley(Author)
- Wayne Jennings(Author)
- Bruce Steinetz(Author)
- Gus Fralick(Author)
- Robert Hendricks(Author)
Benyo and colleagues report gas cycling experiments in which cycling deuterium through a palladium-silver tube produced anomalous behaviour. They suspected palladium fission driven by high energy neutrons from lattice confinement fusion. In bremsstrahlung irradiation experiments, neutron spectroscopy showed evidence of deuterium fusion and higher energy neutrons, while gamma spectroscopy showed evidence of uranium fission products. Electrolytic wet cell experiments gave evidence of deuterium fusion and higher energy neutrons, together with transmutation products observed on the outer co-deposition layer. The talk sets out candidate explanations for the transmutations: electron screened fusion, possible fission pairs, and hybrid fusion fission.
Paper · 2022
LENR Transmutation of Stable Sr and K Isotopes in Activated Microbiological Syntrophic Associations
- Alla Kornilova(Author)
- Sergey Gaydamaka(Author)
- Vladimir Vysotskii(Author)
Alla Kornilova, Sergey Gaydamaka and Vladimir Vysotskii previously reported speeding the decay of reactor caesium-137 by transmutation to barium-138 in growing microbial cultures. Caesium-137 and strontium-90 are the two long-lived reactor isotopes most dangerous to people, because the body absorbs them like potassium and calcium. Here they study stable strontium-88 turning into yttrium-89, as a stand-in for radioactive strontium-90. The work used anaerobic syntrophic microbial associations stimulated at a distance by weak undamped thermal waves. They report synchronised changes in strontium and yttrium, and in potassium and calcium, and suggest yttrium forms because it is a biochemical analogue of calcium.
Paper · 2015
Lessons from Cold Fusion Archives and from History
- Jed Rothwell(Author)
Jed Rothwell draws lessons from the cold fusion archives: the field's results look inconsistent, but history shows such ferment is healthy in emerging science. By contrast, plasma fusion has broad agreement and solid theory but little progress. Drawing on hundreds of the roughly 2000 documents at LENR-CANR.org, he finds the literature proves the effect is real and teaches how to replicate it. Failed experiments come in two kinds, amateur mistakes and noble failures; avoid the first by reading textbooks and the archive papers and consulting an electrochemist. A noble failure was Srinivasan's six months at SRI attempting the bulk nickel-hydrogen excess heat, and success will come through failures like that.
Paper · 2009
Macroscopic quantum electrodynamics and duality
- Stefan Yoshi Buhmann(Author)
- Stefan Scheel(Author)
Stefan Buhmann and Stefan Scheel ask when the duality between electric and magnetic fields is a true symmetry of macroscopic quantum electrodynamics, the theory of quantum light in real materials. The question is timely: magnetic effects are much smaller in natural materials, but recent developments have drawn fresh interest to them. Without free charges, Maxwell's equations are duality invariant at the operator level, although Lorentz forces and atom-field couplings generally are not. They prove that Casimir forces, local-field corrected decay rates and van der Waals potentials stay unchanged under a global swap of electric and magnetic quantities. This exact symmetry lets researchers deduce the physics of new configurations from ones already worked out.
Paper · 2012
Macroscopic quantum electrodynamics in nonlocal and nonreciprocal media
- Stefan Yoshi Buhmann(Author)
- David T Butcher(Author)
- Stefan Scheel(Author)
Buhmann, Butcher and Scheel formulate macroscopic quantum electrodynamics for the most general linear absorbing media, without assuming Onsager reciprocity. Such responses matter because cross-susceptibilities arise naturally in chiral metamaterials, topological insulators and moving media. For nonlocal media, they base field quantisation on the conductivity tensor and the electromagnetic Green tensor. For local media, permittivity, permeability and magnetoelectric susceptibilities give an explicitly duality-invariant scheme. They work out explicitly how the fields, the response functions and the Green tensor behave under duality transformations. Duality invariance holds as a continuous symmetry only when non-reciprocal responses are allowed, whereas simple isotropic media keep only a discrete duality symmetry.