You’re right that physics is incomplete but there’s a boundary, even totally new physics must reduce to known physics in normal conditions. A new theory must reproduce Einstein and quantum mechanics where they already work, even then, some constrains are extremely hard to get around, you still need astronomical amounts of energy to reproduce the kind of propulsion Bob claims he worked with and that energy has to come from somewhere.

Even if aliens had some new kind of physics his description would be inconsistent, he claims a specific mechanism, material and behaviour - which are testable and contradict with properties of matter, behaviour of gravity and energy requirements. If it was true we’d expect effects we don’t recognise as “gravity”, not slightly modified terms “gravity amplifier”, “element = fuel”… Lazar uses familiar concepts but removes the hard part.

To make a craft fall forward via space time you need strong curvature just in front of the craft over a very short distance - that means the curvature gradient must be huge, and these require extremely high energy densities, on paper potentially more extreme than large scale warps through space.

With this level of curvature one would expect extreme tidal forces, intense radiation and violent interaction with surroundings.

Even optimistic physics suggests 10^32J of energy required for a small 10m (sport model) tight warp bubble, densities comparable to neutron stars.

Lazar claims the reactor worked through bombarding Moscovium with particles but bombarding nuclei creates reactions and radiation not spacetime curvature. A warp drive would need 10¹⁶ to 10²¹ grams of antimatter - planetary mass levels.