Here is the original Podkletnov and Modanese paper from 2001, “Impulse Gravity Generator Based on Charged YBa_2Cu_3O_{7-y} Superconductor with Composite Crystal Structure”. You may remember Dr Eugene Podkletnov from his “gravity shielding” experiments with rotating superconductors in the 1990s. This is a different (although possibly related) phenomenon, created by discharging a high voltage Marx generator through a superconductor placed in an intense magnetic field, with a pulse length of 60 to 70 nanoseconds. The claimed effects are wild.
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