Experimental Spacetime Distortion: Generating Gravitational Waves in the Laboratory
Chance Michael Glenn
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Chance Glenn puts a spark gap next to a laser interferometer and watches the fringes. The spark is driven by a transformer reaching about 400,000 volts across tungsten tips filed to half a millimetre; the interferometer is a common-path Michelson with a total optical path of 725 millimetres, run with a green 532-nanometre laser and a red 650-nanometre one. When the spark fires, the fringes move — in step with the spark, by up to about 160 nanometres, always in the direction of a longer optical path, and falling away with distance from the spark. Most of the paper is the work of eliminating everything else it could be. Vibration is ruled out by the isolation platform and by moving the spark away while it keeps running. A changing refractive index is ruled out three ways: turning the spark through ninety degrees changes nothing, the two laser colours give nearly identical displacements where refraction predicts a ratio of 1.22, and white light near the spark produces no rainbow.
Why it matters hereChapter 4 argues that the metric is something you can act on, and this is one of the few papers with a bench, a budget and a number: a tabletop apparatus, an interferometric measurement, and a named list of the next experiments. Chapter 1 gets to watch the controls being run in public.
What it claims
01The apparatus is a high-voltage spark gap — a transformer capable of about 400,000 volts across tungsten rods filed to points of roughly 0.5 mm, with adjustable gap distance and a signal generator setting the repetition rate — observed with a common-path Michelson interferometer using 532 nm and 650 nm lasers, mirrors 150 mm from the splitter, screen 500 mm away, and a total optical path length of 725 mm.Section 3, Experimental Setup and Methodology
On the bench now02The interferometer consistently shows fringe movement synchronised with spark formation, reaching displacements of about 140 to 160 nanometres, always in the direction of an increase in optical path length, with a ringing settle after the pulse ends; the magnitude decreases with distance from the spark and drops off completely at around 20 mm, symmetrically on both sides of the beam.Section 4, Experimental Results, Figs. 10–13; Section 5.1
On the bench now03The competing explanations are each addressed with a control. Vibration and shock: the testbed sits on a vibration-resistant platform and the effect vanishes when the running spark is moved away on the same platform. Refractive index: orientations of 0 and 90 degrees give the same magnitude where Snell’s law predicts a significant difference; the 532 nm and 650 nm displacements are nearly identical where an index change predicts a ratio of 1.22; and white light near the spark shows no chromatic dispersion. Replacing air with helium does not remove the effect and makes it more pronounced.Section 4, mitigation strategies; Section 5.1, Summary of Observations, Eqs. 13–16
On the bench now04The response scales with energy density as the hypothesis requires. Adjusting input power and gap width isolated energy densities of 1.4 and 2.4 gigajoules per cubic metre, with power densities reaching one times ten to the eleventh watts per cubic metre at a 2.5 mm gap and eight times ten to the tenth at 5 mm; displacement rises with input power and the fringe movement tracks the spark repetition frequency.Section 4, Figs. 14–15; Section 5.1, Power Scaling and Energy Density
On the bench now05With multiple spark gaps placed in series the fringe movement appears to be additive, which Glenn proposes building on as a phased array of gwavelets — a four-by-four arrangement of spark-gap elements driven in amplitude, phase and frequency to shape and steer the resulting distortion, with fusion stabilisation, communications and propulsion named as the applications that would follow.Section 5.1, Series Configuration of Spark Gaps; Section 5.2; Fig. 16
Designed, not yet built06The next measurements are named: raise the energy density in a vacuum and in other gases, find the optimal drive frequency for maximising the distortion, and test the additional influence of rotational fields. The work is supported by a Phase I Small Business Innovation Research grant from the National Science Foundation, with Alabama A&M University providing research space.Section 6, Conclusion; Acknowledgment
What to watch
The way in
https://doi.org/10.24018/ejeng.2025.10.2.3246Open access under a Creative Commons Attribution 4.0 licence, so the full paper may be freely read, redistributed and reused with attribution; this page carries a summary and the publisher’s PDF is one click away.
How to cite it
Chance Michael Glenn (2025) Experimental Spacetime Distortion: Generating Gravitational Waves in the Laboratory. doi:10.24018/ejeng.2025.10.2.3246
Where it sits in the curriculum
The metric, warp drives and wormholesGravity control and superconductorsThe evidence ladder