Types Field propulsion

1 types

1.1 practical methods
1.2 speculative methods
1.3 field propulsion based on physical structure of space
1.4 conservation laws
1.5 advantages

types
practical methods

although not presently in wide use space, there exist proven terrestrial examples of field propulsion , in electromagnetic fields act upon conducting medium such seawater or plasma propulsion, known magnetohydrodynamics or mhd. mhd similar in operation electric motors, rather using moving parts or metal conductors, fluid or plasma conductors employed. ems-1 , more yamato 1 examples of such electromagnetic field propulsion systems, first proposed in patent 5333444 . there potential apply mhd space environment , experiments such nasa s electrodynamic tether, lorentz actuated orbits, wingless electromagnetic air vehicle, , magnetoplasmadynamic thruster (which use propellant) lay solid foundation using fields propel spacecraft without propellant , standard concepts of chemical thrust. since electrodynamics proven science, electromagnetic fields carry momentum (see nichols radiometer), , electromagnetic field propulsion not limited ejection velocity of particle propellants, these new concepts offer tremendous potential future space propulsion system. represent radical departure current ideas of aeronautics , rocket propulsion, , such controversial, field propulsion may offer radical breakthroughs in performance capabilities required deep space exploration. main limiting factors appear generation of significant amounts of electrical power required , method of coupling fields large volumes.

electrohydrodynamics method whereby electrically charged fluids used propulsion , boundary layer control such ion propulsion

other practical methods loosely considered field propulsion include: gravity assist trajectory, uses planetary gravity fields , orbital momentum; solar sails , magnetic sails use respectively radiation pressure , solar wind spacecraft thrust; aerobraking uses atmosphere of planet change relative velocity of spacecraft. last 2 involve exchange of momentum physical particles , not expressed interaction fields, included examples of field propulsion since no spacecraft propellant required.

speculative methods

other concepts have been proposed speculative, using frontier physics , concepts modern physics. far none of these methods have been unambiguously demonstrated, less proven practical.

the woodward effect based on controversial concept of inertia , solutions equations general relativity. experiments attempting conclusively demonstrate effect have been conducted since 1990s.

although speculative, ideas such coupling momentum flux of zero-point electromagnetic wave field hypothesized in stochastic electrodynamics have plausible basis further investigation within existing theoretical physics paradigm.

in contrast, examples of proposals field propulsion rely on physics outside present paradigms various schemes faster-than-light, warp drive , antigravity, , amount little more catchy descriptive phrases, no known physical basis. until shown conservation of energy , momentum break down under conditions (or scales), such schemes worthy of discussion must rely on energy , momentum transfer spacecraft external source such local force field, in turn must obtain still other momentum and/or energy sources in cosmos (in order satisfy conservation of both energy , momentum).

field propulsion based on physical structure of space

this concept based on general relativity theory , quantum field theory idea space has physical structure can proposed. macroscopic structure described general relativity theory , microscopic structure quantum field theory. idea deform space around space craft. deforming space possible create region higher pressure behind space craft before it. due pressure gradient force exerted on space craft in turn creates thrust propulsion. due purely theoretical nature of propulsion concept hard determine amount of thrust , maximum velocity achieved. there 2 different concepts such field propulsion system 1 purely based on general relativity theory , 1 based on quantum field theory.

in general relativistic field propulsion system space considered elastic field similar rubber means space can treated infinite elastic body. if space-time curves, normal inwards surface stress generated serves pressure field. creating great number of curve surfaces behind space craft possible achieve unidirectional surface force can use acceleration of space craft.

for quantum field theoretical propulsion system assumed, stated quantum field theory , quantum electrodynamics, quantum vacuum consists out of zero-radiating electromagnetic field in non-radiating mode , @ zero-point energy state, lowest possible energy state. theorized matter composed out of elementary primary charged entities, partons, bound elementary oscillators. applying electromagnetic 0 point field lorentz force applied on partons. using on dielectric material effect inertia of mass , way create acceleration of material without creating stress or strain inside material.

conservation laws

conservation of momentum fundamental requirement of propulsion systems because in experiments momentum conserved, , implicit in published work of newton , galileo. in each of propulsion technologies, form of energy exchange required momentum directed backward @ light speed c or lesser velocity v balance forward change of momentum. in absence of interaction external field, power p required create thrust force f given.

f = p/v when mass ejected or f=p/c if mass free energy ejected.

for photon rocket efficiency small competitive. other technologies may have better efficiency if ejection velocity less light speed, or local field can interact large scale field of same type residing in space, intent of field effect propulsion.

advantages

the main advantage of field propulsion systems no propellant needed, energy source. means no propellant has stored , transported space craft makes attractive long term interplanetary or interstellar manned missions. current technology large amount of fuel meant way has brought destination increases payload of overall space craft significantly. increased payload of fuel, requires more force accelerate it, requiring more fuel primary drawback of current rocket technology. approximately 83% of hydrogen-oxygen powered rocket, can achieve orbit, fuel.