Gravitomagnetic London Moment
| Gravitomagnetic London Moment | |
|---|---|
| Overview | |
| Theoretical Basis | Li-Torr gravitomagnetic coupling (1991) |
| Analog of | Electromagnetic London moment |
| Key Prediction | Amplified Bg from rotating superconductor (~10¹¹× GR) |
| Experimental Evidence | Tate Experiment (indirect, 84 ppm); Tajmar (direct, disputed) |
| Engineering Application | Magneto Speeder rotor array design basis |
| Status | Theoretical · Partially supported by experiment |
| The core mechanism connecting conventional superconductor physics to magnetogravitic propulsion | |
| ⚡️ | Electrogravitics - Electrogravitic Tech | Electrokinetics - Electrokinetic Tech |
| 🧲 | Magnetogravitics - Magnetogravitic Tech | Magnetokinetics - Magnetokinetic Tech |
The gravitomagnetic London moment is the predicted gravitational analog of the well-known electromagnetic London moment. Just as a spinning superconductor generates a magnetic field aligned with its rotation axis (the London moment), Ning Li and Douglas Torr predicted in 1991 that the same spinning superconductor generates a gravitomagnetic field — a field that acts on mass the way magnetic fields act on charge. [1]
This mechanism is the central theoretical pillar of the Magneto Speeder's propulsion system. If the gravitomagnetic London moment can be engineered to sufficient strength, a rotor array of spinning superconductors could generate controllable gravitational thrust.
The Electromagnetic London Moment
The standard London moment is one of the most precisely verified predictions of superconductor physics. When a superconductor rotates at angular velocity , the Cooper pairs (which carry the supercurrent) lag behind the lattice, creating a net current that generates a magnetic field: [2]
Key properties:
- The coefficient is universal — independent of material, geometry, or temperature
- The field is exactly proportional to angular velocity
- This was confirmed experimentally to high precision (e.g. Gravity Probe B used it for gyroscope readout)
- The Tate Experiment measured it to 84 ppm precision and found an anomalous mass excess
The Gravitomagnetic London Moment
Physical Motivation
In Gravitoelectromagnetism, any rotating mass generates a gravitomagnetic field (frame-dragging):
For laboratory-scale masses, this field is fantastically weak (~10⁻²⁶ rad/s per rad/s of angular velocity). [3]
However, in a superconductor, Ning Li argued that the quantum coherence of the condensate creates a qualitatively different situation. The Cooper pairs are locked to one another across the entire superconductor, forming a macroscopic quantum state. When this state interacts with the lattice ions, the gravitomagnetic coupling is amplified by a factor related to the ion density.
The Li-Torr Derivation
Li and Torr began from the electromagnetic London equation:
where is the Cooper pair mass, is the superfluid number density, is the Cooper pair charge, and is the supercurrent density.
By analogy, they introduced a gravitomagnetic London equation: [4]
where is the mass-current density of the superfluid. The critical step is recognizing that in a rotating superconductor, the mass current involves both the Cooper pairs and (via quantum-mechanical coupling) the lattice ions.
Amplification Mechanism
The electromagnetic London moment depends only on the electron mass because the Cooper pairs carry charge but the lattice ions do not. For the gravitomagnetic case, everything carries mass — both the Cooper pairs and the lattice ions.
In a normal material, the lattice and conduction electrons move independently and their gravitomagnetic contributions are negligible and incoherent. In a superconductor, the Cooper condensate is quantum-mechanically locked to the lattice (via the electron-phonon interaction that creates Cooper pairs in the first place). This locking means the gravitomagnetic contribution of the massive lattice ions (~10⁵ × heavier than electrons per unit cell) is coherently added.
Li-Torr predicted the gravitomagnetic field of a rotating superconductor:
where:
- is the Cooper pair effective mass (measured by Tate Experiment)
- is the lattice ion mass
- is the coherence amplification factor (~10¹¹ over classical GR)
- is the angular velocity
The Amplification Factor
The amplification factor arises from:
| Source | Contribution | Approximate magnitude |
|---|---|---|
| Ion/electron mass ratio | ~10⁵ (for Nb, ) | |
| Cooper pair density | All pairs coupled coherently | ~10²² per cm³ |
| Coherence volume | Pairs correlated over coherence length | ~10⁻⁵ m (Nb) |
| Total vs GR | Product of all factors ÷ GR prediction | ~10¹¹ |
The net result: where classical GR predicts ~10⁻²⁶ rad/s per rad/s, Li-Torr predicts ~10⁻¹⁵ rad/s per rad/s. Still extremely small, but:
- 11 orders of magnitude larger than the GR prediction
- Potentially measurable with precision gyroscopes (which is exactly what Martin Tajmar attempted)
Experimental Evidence
| Experiment | Year | Measurement | Supports Gravitomagnetic London Moment? |
|---|---|---|---|
| Tate Experiment | 1989 | Cooper pair mass excess = 84 ± 2 ppm | Indirect support — anomaly is consistent with gravitomagnetic coupling |
| Podkletnov | 1992 | Weight reduction above spinning YBCO disc | Unconfirmed — never independently replicated |
| Tajmar (initial) | 2006 | ~10⁻⁸ coupling in spinning Nb ring | Possible detection — ~10¹⁸× GR prediction |
| Tajmar (revised) | 2012 | Helium artifact identified | Inconclusive — effect may be mundane |
| Gravity Probe B | 2011 | Confirmed GR frame-dragging in space | Validates GEM framework — no superconductor amplification tested |
| NASA BPP | 1996–2002 | Attempted Li-Torr replication | No detection — but sensitivity may have been insufficient |
The Measurement Gap
The Li-Torr prediction (~10⁻¹⁵ rad/s per rad/s) falls in a difficult gap:
- Too weak for mechanical detectors (which bottom out at ~10⁻¹² rad/s)
- Too strong for astronomical observation (which works at ~10⁻²⁶)
- Just barely within range of precision fiber-optic or ring-laser gyroscopes
Tajmar's reported coupling of ~10⁻⁸ is actually much stronger than Li-Torr predicted. If Tajmar's signal is real, it implies additional amplification mechanisms beyond what Li-Torr calculated.
Engineering Requirements
For the Magneto Speeder, the required gravitomagnetic field strength to produce measurable thrust:
where is the vehicle mass density, is volume, is velocity, and is the gravitomagnetic field.
To hover a 1000 kg vehicle against Earth's gravity (9.8 m/s²):
(assuming vehicle structural velocity m/s through the gravitomagnetic field)
| Parameter | Li-Torr Prediction | Tajmar Measurement | Required for Magneto Speeder |
|---|---|---|---|
| coupling | ~10⁻¹⁵ | ~10⁻⁸ (disputed) | ~10⁻¹ to 1 |
| Gap from Li-Torr | — | 10⁷× stronger | 10¹⁴× stronger |
| Gap from Tajmar | — | — | 10⁷× stronger |
| Rotor angular velocity | ~100 rad/s | ~420 rad/s | ~10⁴ rad/s (design target) |
This gap defines the engineering challenge of the Magneto Speeder — achieving the amplification factors needed for practical thrust generation.
Proposed Amplification Strategies
| Strategy | Mechanism | Potential Gain |
|---|---|---|
| Higher materials | Stronger electron-phonon coupling may → stronger gravitomagnetic coupling | Unknown (YBCO, MgB₂, H₃S) |
| Multiple rotor array | Constructive superposition of B_g fields | Linear in number of rotors |
| Resonant oscillation | Time-varying ω may access resonant amplification (Li-Torr 1993) | Potentially exponential [5] |
| Nested counter-rotation | Counter-rotating nested shells amplify gradient | ~N² for N shells |
| Pais Effect integration | HEEMFG field + superconductor hybrid | Speculative |
Connection to Kaluza-Klein Theory
In the Kaluza-Klein Unification framework, the gravitomagnetic London moment has a deeper interpretation. The 5D metric unifies gravity and electromagnetism, meaning the electromagnetic London moment and the gravitomagnetic London moment are projections of the same 5D phenomenon onto different sectors of the metric.
The electromagnetic London moment measures (off-diagonal metric components), while the gravitomagnetic London moment measures (gravitomagnetic sector). In the full 5D theory, these are coupled:
A change in (electromagnetic, i.e. conventional London moment) necessarily implies a change in (gravitomagnetic) through the off-diagonal coupling — precisely what Li-Torr predicted from a bottom-up condensed-matter approach.
Mathematical Chain
The complete theoretical chain from established physics to engineering application:
| Step | Physics | Status |
| 1 | KK: EM = geometry of 5th dimension | Established theory |
| 2 | GEM: weak-field GR → Maxwell-like equations | Established (confirmed by Gravity Probe B) |
| 3 | London moment: spinning SC → magnetic field | Established (precision-verified) |
| 4 | Tate: Cooper pair mass has 84 ppm anomaly | Experimental fact (interpretation disputed) |
| 5 | Li-Torr: anomaly = gravitomagnetic coupling | Peer-reviewed theory |
| 6 | Gravitomagnetic London moment: spinning SC → B_g field | This page — theoretical prediction |
| 7 | Tajmar: possible detection of B_g near spinning SC | Experimental (disputed/inconclusive) |
| 8 | Rotor array: engineering B_g for thrust | Speculative engineering |
See Also
- Gravitoelectromagnetism
- Kaluza-Klein Unification
- Ning Li
- Tate Experiment
- Martin Tajmar
- Gravity Probe B
- Magnetogravitics
- Magneto Speeder
- Magnetogravitic Tech
- Pais Effect
References
- ↑ Li, N. & Torr, D.G. (1991). "Effects of a gravitomagnetic field on pure superconductors." Physical Review D 43(2), 457–459. doi:10.1103/PhysRevD.43.457
- ↑ London, F. (1950). Superfluids, Vol. 1. Wiley, New York.
- ↑ Mashhoon, B. (2003). "Gravitoelectromagnetism: A Brief Review." In: Iorio, L. (ed.) The Measurement of Gravitoelectromagnetism: A Challenging Enterprise. Nova Science. arXiv:gr-qc/0311030
- ↑ Li, N. & Torr, D.G. (1991). "Gravitational effects on the magnetic attenuation of superconductors." Physical Review B 44(10), 5081–5083. doi:10.1103/PhysRevB.44.5081
- ↑ Li, N. & Torr, D.G. (1993). "Gravitoelectric-electric coupling via superconductivity." Foundations of Physics Letters 6(4), 371–383. doi:10.1007/BF00665654