Advanced Space Propulsion Based on Vacuum (Spacetime Metric) Engineering

The paper says vacuum or spacetime-metric engineering for spaceflight is far-reaching but not ruled out a priori by modern physical theory.

Although far reaching, such a proposal is solidly grounded in modern physical theory, and therefore the possibility that matter/vacuum interactions might be engineered for spaceflight applications is not a priori ruled out

The paper states that the energy densities predicted for significant spacetime-metric perturbation exceed existing engineering capabilities by many orders of magnitude.

the required energy densities predicted by present theory exceed by many orders of magnitude values achievable with existing engineering techniques.

Its model-independent metric-tensor method assumes, rather than demonstrates, that a technology exists to control and manipulate spacetime.

it does not depend on knowledge of the specific mechanisms or dynamics that result in spacetime alterations but rather only assumes that a technology exists that can control and manipulate (that is, engineer) the spacetime metric to advantage.

The paper predicts that a hypothetical craft with an accelerated internal timeframe could appear to accelerate abruptly to an outside observer while occupants experience a more modest change in motion.

its flightpath that might seem precipitous from an external viewpoint (for example, sudden acceleration or deceleration) would be experienced as much less so by the craft’s occupants.

The paper hypothesizes that strengthened material binding energies in a metric-engineered region could allow a craft to strike water at high speed without apparent damage.

Such a craft could, for example, impact water at high velocities without apparent deleterious effects.

The paper explains that the Alcubierre metric permits arbitrarily large apparent faster-than-light speed for distant observers without locally exceeding light speed.

the spacecraft can be made to exhibit an arbitrarily large apparent faster-than-light speed as viewed by external observers without violating the local speed-of-light constraint within the spacetime-altered region.

The paper says an Alcubierre warp bubble would require exotic matter with negative energy or pressure and that its technical requirements were unlikely to be met in the foreseeable future.

one would have to construct a “warp bubble” that surrounded the spacecraft by generating a thin shell or surface layer of exotic matter—that is, a quantum field having negative energy and/or negative pressure.

The discussion states that significant peer-reviewed physics literature explores vacuum or metric engineering, but the analysis still assumes controllable spacetime variables.

a significant literature exists in peer-reviewed, Tier 1 physics publications in which the topic is explored in detail.

The paper concludes that it was premature to identify an optimum engineering strategy or a critical development path for the proposed technologies.

given our present level of technological evolution, it is premature to even guess about an optimum strategy, let alone attempt to form a critical path for the engineering development of such technologies.