Gravitational Field Propulsion Technologies: From Superconducting Coils to Warp Drives

September 27, 2026

Could a spacecraft move by engineering the gravitational environment around it? For researcher Gary Stephenson, answering that question starts with separating a collection of ideas into specific physical mechanisms, proposed experiments, and unresolved engineering problems. His survey of gravitational field propulsion technologies stretches from superconducting coils and oscillating fusion plasmas to warp drives, quantum transitions, and speculative forms of teleportation. Developed through his volunteer work with the Scientific Coalition for UAP Studies, the project asks whether any of these approaches could help explain unusual aerospace observations—and, more practically, whether they could point toward technologies humans might eventually build.

Building a Map of Gravitational Propulsion

Stephenson’s investigation began with an assignment from the Scientific Coalition for UAP Studies, or SCU. After joining the all-volunteer organization, he asked where his background could be most useful. Because he’d worked on gravitational waves, the organization asked him to examine gravitational field propulsion: Did the idea make physical sense, could it conceivably relate to UAP behavior, and might it offer a starting point for developing human-built vehicles?

Rather than championing a single device, Stephenson organized the possibilities into two broad categories. The first encompasses classical approaches based on general relativity, including moving mass, generating gravitational waves, and shaping spacetime geometry. The second explores quantum approaches, including proposed transitions that could emit gravitational radiation and ideas involving specially conditioned materials. That distinction gives the survey its structure while allowing very different mechanisms to be considered without treating them as interchangeable.

A second part of the assignment was to submit the material for expert review. Stephenson says he presented the survey at the Marcel Grossmann 17 meeting in Italy, where researchers working on general relativity could examine it. According to his account, the work subsequently appeared in the conference proceedings following peer review. He’d previously presented related research at Marcel Grossmann 15 and 16, particularly his investigations of superconducting mass-flow configurations.

The result is a taxonomy rather than a blueprint for a finished engine. Some entries concern mathematical descriptions of spacetime, others propose ways to generate a measurable gravitational signal, and still others extend into much more speculative territory. Throughout the presentation, an important distinction emerges: producing a gravitational interaction isn’t automatically the same thing as producing propulsion. A workable vehicle would require a controlled effect that goes beyond demonstrating that an interaction exists.

Revisiting Robert Forward’s Mass-Flow Coil

The approach Stephenson knows best traces back to Robert Forward, whose career overlapped with his at Hughes. Stephenson worked at Hughes Aircraft while Forward was associated with the company’s Malibu research laboratories. Forward’s proposal, first published in the early 1960s, involved a coil carrying a circulating flow of mass. In Stephenson’s description, that motion would produce a Lense–Thirring effect in the surrounding spacetime, with the geometry concentrating the interaction toward the coil’s center.

The obstacle was scale. Stephenson characterizes the original concept as requiring enormous amounts of circulating mass—“huge numbers of solar masses”—to produce the desired result. That made it difficult to connect the theoretical configuration to anything resembling laboratory hardware. He returned to the problem in work he dates to 2019 and 2021, prompted by a collaboration involving nanotechnology and the possibility of carrying exceptionally large electrical currents through superconducting wires.

In the revised concept, the circulating mass would be carried by electrons rather than a macroscopic stream of material. Stephenson argues that very high currents, combined with electrons accelerated toward the speed of light, could make the configuration worth reconsidering. His proposal relies on the gravitational contribution of that energetic flow. He presents it as a possible route toward a measurable effect, not as an experimentally established method of generating useful thrust.

A further connection made the geometry especially interesting to him: it resembles superconducting magnetic energy storage, or SMES, technology, which he says the Department of Energy has investigated for energy storage. Stephenson proposes leveraging that engineering heritage to study a gravitational potential concentrated inside a toroidal coil and more dispersed around its edges. Placing a larger mass in the central region is part of his suggested arrangement, although his presentation doesn’t report a measured propulsive force from it.

Generating Gravitational Waves with Fusion Plasma

Another branch of Stephenson’s work asks whether controlled plasma motion inside a tokamak could generate gravitational waves. He says he first developed calculations for this approach in 2003, then revisited it for a high-frequency gravitational-wave summit in Chengdu, China, in 2017. He also identifies Andy Beckwith as a researcher who has explored related questions. The central idea is to use organized changes in a plasma’s mass-energy distribution as the source.

The motion must have the appropriate structure. Stephenson describes plasma oscillating in a quadrupole pattern rather than merely moving back and forth as a single undifferentiated mass. In the gravitational-wave power relationship he discusses, the relevant quantity involves the square of the third time derivative of the mass quadrupole moment. His emphasis is therefore on both geometry and how rapidly the distribution changes—not simply on how much plasma the apparatus contains.

Ordinary plasma motion wasn’t enough for the effect he wanted to investigate. According to Stephenson, the calculations didn’t produce a sufficiently large change in mass-energy to make a measurement promising. That led him toward a burning plasma undergoing fusion. He describes alternating activity between fusion nodes, with the changing distribution supplying an additional contribution beyond the motion of non-fusing plasma alone.

Even that would address only the generation problem. As Stephenson puts it, “Now, that still doesn’t get us to propulsion.” A source could produce an oscillating gravitational disturbance without functioning as a useful engine. His next question is whether the oscillation could be arranged or transformed into a directional effect—a separate challenge that occupies an important place in the survey.

Turning an Oscillation into a Directional Effect

Stephenson describes this challenge as gravitational-wave rectification: trying to turn an alternating interaction into something that behaves more like a sustained directional influence. His proposed starting point is an asymmetric cycle. The plasma would move rapidly in one direction and return more slowly in the other. Because the power relationship is highly sensitive to the rate of change, he argues that the fast impulse and slow relaxation could contribute very differently.

The next step involves combining two toroidal configurations. Stephenson proposes arranging their emissions so that gravitational waves reinforce one another in selected regions around a craft. In his description, the geometry would produce constructive interference on one side while allowing part of the radiation to escape elsewhere. The intended result is a directional effect arising from the timing and spatial arrangement of the sources, rather than from a single symmetric oscillation.

He’s explicit about a limitation of this particular scheme: its rectification efficiency could never exceed 50%, and would probably be substantially lower. That figure isn’t a demonstrated propulsion efficiency or an overall electrical-to-thrust conversion rate. It’s the ceiling he assigns to the wave-handling arrangement he describes, in which part of the generated radiation is effectively discarded. Generating the radiation strongly enough in the first place remains an additional problem.

Stephenson also mentions the Christodoulou memory effect as another possible avenue. He describes it as a permanent displacement remaining after a gravitational-wave disturbance has passed, raising the question of whether such a displacement could contribute to propulsion. Here again, he presents a possibility to investigate rather than a completed mechanism. His discussion doesn’t establish how that effect would become a repeatable, controllable propulsion cycle.

Converting Electromagnetic Energy into Gravitational Waves

Moving plasma isn’t the only proposed source in Stephenson’s classical category. He also discusses the Gertsenshtein effect, which he describes as a route for converting part of an electromagnetic wave into gravitational radiation when the wave encounters a strong magnetic field. Unlike the plasma proposal, this approach begins with electromagnetic fields rather than deliberately oscillating a bulk mass distribution.

Stephenson references his own 2005 paper in connection with this subject and discusses related work by Boccaletti. In his account, those studies broaden the range of possible field arrangements, including static electric fields, magnetic fields, or combinations of the two interacting with electromagnetic radiation. He places these proposals within calculations based on Einstein’s classical field equations, distinguishing them from the quantum-transition concepts introduced later.

The source could operate with pulses or a continuous stream, according to the configurations he describes. That provides several ways to imagine an experimental arrangement, but changing the waveform doesn’t by itself answer the central engineering question. The apparatus would still need to produce enough gravitational radiation to distinguish the effect from the much larger electromagnetic activity used to drive it.

Stephenson acknowledges that difficulty directly, saying it’s “highly debatable whether it’s strong enough to ever have a measurable effect.” That qualification defines the status of this part of the survey. The proposed conversion mechanism offers something to calculate and investigate, but his presentation doesn’t supply a measured conversion efficiency, a demonstrated gravitational-wave source of useful strength, or propulsion hardware based on it.

Warp Drives, Wormholes, and Shaped Gravitational Fields

Warp drives approach the problem from another direction: specify a spacetime configuration that could produce the desired motion, then confront the question of how to create it. Stephenson begins with Alcubierre’s familiar proposal and points to subsequent alternatives, including Natário’s work. He emphasizes research intended to reduce energy requirements, presenting the field as an evolving collection of mathematical solutions rather than a single design that has remained unchanged.

One distinction particularly interests him: whether a proposed configuration merely maintains a steady state or includes acceleration. He describes a family of six metrics, including a globally accelerating case, as especially noteworthy. In the context of his survey, that matters because describing a moving spacetime configuration and explaining how a craft could change its motion are different problems. His enthusiasm concerns the expanding mathematical possibilities, not an announcement that the necessary machinery exists.

Stephenson places wormholes alongside warp drives because both would require deliberate manipulation of spacetime geometry. He distinguishes a wormhole by its connecting, hole-like structure, rather than treating it as simply another shape of warp bubble. The common engineering question is how the required stretching or restructuring of spacetime could be produced. His presentation surveys these geometries without providing a construction method for either a navigable wormhole or an operational warp drive.

He also discusses work by Matt Visser and collaborators on specially shaped fields that could act as tractor, pressor, or stressor beams. A tractor beam would pull, a pressor beam would push, and a stressor configuration would apply differential forces. These examples extend the discussion beyond moving an entire vehicle to manipulating other objects. Stephenson makes their status clear: “Obviously, it’s not experimental yet, but it’s a mathematically interesting case.”

Quantum Transitions as Gravitational-Wave Sources

The quantum portion of the survey changes the proposed source of the interaction. Instead of relying on large circulating currents or bulk plasma motion, Stephenson asks whether carefully selected quantum transitions could emit gravitational radiation directly. He credits work by Fontana and connects the topic to an earlier presentation he’d given for Ventura’s conference. The key mechanism under consideration is a spin-2 transition.

Stephenson discusses a superconducting junction as a possible setting for stimulating such transitions. Although the materials might initially be described in terms of high- and low-temperature superconductors, he says that temperature labels aren’t the decisive distinction. In his account, the important contrast is between Type I and Type II superconductors because of the quantum transitions associated with the proposed arrangement.

He summarizes the particle-count relationship as a “divide-by-2 situation” and describes a reciprocal detector concept in which an absorbed graviton would yield two photons. The proposed emission and detection processes are therefore linked: the same general interaction being explored as a source could also motivate a receiver. These are descriptions of a proposed conversion scheme, not reports that individual gravitons have been generated and detected with the apparatus.

Detection also gives the research a purpose beyond propulsion. Stephenson highlights the possibility of high-frequency gravitational-wave astronomy and asks whether quantum devices could provide a way to investigate that regime. The prospect of a useful detector doesn’t depend on first building a gravitational engine. In this part of the survey, the ambition broadens from moving spacecraft to creating instruments capable of observing gravitational phenomena.

Metamaterials and Vacuum Metric Engineering

Stephenson next considers whether specially conditioned metamaterials might provide another route to shaping spacetime. He references work associated with Sarfatti and connects it to conceptual descriptions of a Tic Tac-shaped vehicle. The proposal is conditional: it depends on materials with the required properties and an interaction capable of producing the intended spacetime effect. He doesn’t present a tested material that has already achieved that result.

A related question concerns whether engineered materials could influence the light-cone structure associated with space and time. Stephenson includes this as part of the broader search for ways to control gravitational behavior through material properties rather than through enormous moving masses. His presentation outlines the research direction, but doesn’t specify a verified material composition, fabrication process, or measured performance for a propulsion application.

Vacuum metric engineering takes the discussion from material structures to the proposed conditioning of vacuum fluctuations. In Stephenson’s description, the objective is to manipulate quantities represented as spacetime density or an effective refractive index, using energy rather than simply introducing more matter. Those terms belong to the models he’s reviewing; the presentation doesn’t demonstrate an apparatus that can adjust them on demand.

He points to Hal Puthoff’s work in the late 1990s and early 2000s as a familiar example, alongside related ideas associated with Morris, Thorne, and Visser. Within the survey, vacuum metric engineering also connects propulsion to teleportation because it raises the possibility of changing the environment through which motion occurs. The proposed advantage is control over spacetime itself, while the unresolved issue is how that control would be physically implemented.

Teleportation: Changing the Meaning of Travel

For the teleportation portion of the survey, Stephenson relies heavily on Eric Davis’s 2004 study for Edwards Air Force Base. He describes it as an extensive review containing roughly 250 references and adopts its categories to organize several very different possibilities. These include vacuum metric engineering, quantum-entanglement approaches, extra-dimensional scenarios, and alleged psychokinetic effects. Including them in one survey doesn’t make them equivalent mechanisms or place them at the same evidentiary level.

In discussing entanglement-based concepts, Stephenson uses an analogy of destructive reading at one location and reconstruction at another. He compares the imagined process to destroying an object while reading its state, then recreating that state elsewhere—something like coordinated three-dimensional disassembly and printing. His account extends into a speculative matter-reconstruction scenario; it isn’t a report of a demonstrated system for teleporting a macroscopic object.

Stephenson draws on Figures 6 and 7 from Davis’s study to explain the distinction between copying and reconstruction. A conventional fax-machine analogy leaves an original behind while producing a copy elsewhere. The scenario he describes instead involves destroying the original state during the reading process. The diagrams serve as conceptual illustrations of what such a process would mean, rather than engineering plans for a working transporter.

Extra-dimensional approaches introduce a different possibility: reaching another location through a structure beyond the familiar spacetime description. Stephenson references Kaluza–Klein theory and work by Randall and Sundrum while acknowledging the gap between mathematically characterizing additional dimensions and accessing them. He notes that the original Kaluza–Klein formulation wasn’t a teleportation proposal. The question is whether such frameworks could ever be extended into a usable transportation mechanism.

The Most Speculative Part of the Survey

Stephenson reserves the psychokinetic claims for the end, describing this as the topic he finds most troubling and knows least about. Drawing from Davis’s review, he discusses reports from China and the former Soviet Union involving people allegedly moving objects between sealed containers. These accounts are presented as claims in the literature he surveyed, not as experiments Stephenson conducted or independently verified.

The reported procedures included high-speed cameras and, in at least one account, a radio-emitting device placed inside an object. Stephenson recounts descriptions of objects disappearing for periods ranging from seconds to minutes before appearing elsewhere. He also describes a claim that the embedded transmitter’s signal disappeared while the object was absent and resumed after its reported reappearance. The interview doesn’t provide the underlying experimental records needed to evaluate those accounts.

An important boundary applies to the publication history. Stephenson explicitly says he omitted the psychokinetic material from his Marcel Grossmann presentation because the meeting’s focus was classical general relativity. His statement that the conference work underwent peer review therefore shouldn’t be read as validation of these teleportation claims. This portion of the interview is separate from the material he says he presented there.

He also mentions neuroquantology as an area he wants to watch for possible connections between brain function and unusual physical claims, while describing it as being in disarray. His interest is exploratory: could something missing from the current account of these phenomena eventually suggest new physics? The interview establishes that he considers the question worth examining, but it doesn’t establish that psychokinetic teleportation occurs or that it offers an engineering path to propulsion.

From Proposed Mechanisms to Observable Signatures

Stephenson’s next research step is more discriminating than simply expanding the catalog. He wants to compare the expected signatures of different proposed propulsion mechanisms with reported UAP observations. “Every different form of propulsion has its own characteristic signatures,” he says. The objective is to determine what each mechanism should produce and whether those expectations line up with the available observations.

At the time of the presentation, he identified an SCU meeting in Huntsville on June 6–8 as a venue for reporting on that work. He described the taxonomy as the preceding phase of the investigation, with the signature comparison representing the next stage. The interview doesn’t present a completed ranking of mechanisms or identify one as the established explanation for UAP behavior. It outlines the comparison he intended to pursue.

That transition matters because the survey contains several distinct technical challenges. Forward-style coils raise questions about circulating mass-energy and measurable field strength. Plasma and electromagnetic sources confront the difficulty of generating useful gravitational radiation. Rectification introduces the additional problem of producing a directional effect, while warp metrics and quantum proposals require their own physical implementations. An interesting calculation in one category doesn’t automatically solve the problems in another.

The central question running through Stephenson’s survey is therefore not which proposal looks most like science fiction, but which interaction can become a measurable, repeatable, and controllable effect. His taxonomy offers a way to organize that search without pretending every entry is equally mature. For gravitational field propulsion to progress from a collection of possibilities into a technology, the decisive bridge will be between a proposed mechanism, an observable signature, and an experiment that can demonstrate the connection.