Various Aspects of Exotic Propulsion Systems
November 5, 2010 1 Comment
Travelling into the dark is too hazardous especially if you wish to contact extraterrestrial civilization–even at a high relativistic speed, it would take almost 21 years to reach to the nearest earth like planet, Gliese 581 g. Various mechanisms have been proposed to make it possible within our short life times however, none of them are either feasible to accomplish the mammoth task of interstellar travel. Almost all of them have already been reviewed on WeirdSciences[select category ‘quantum physics/astrophysics’].
One means to produce force is collisions. Conventional rocket propulsion is fundamentally based on the collisions between the propellant and the rocket. These collisions thrust the rocket in one direction and the propellant in the other.To entertain the analogy of collision forces for a space drive, consider the supposition that space contains a background of some form of isotropic medium that is constantly impinging on allsides of a vehicle. This medium could be a collection of randomly moving particles or electromagnetic waves, either of which possess momentum. If the collisions on the front of a vehicle could be lessened and/or the collisions on the back enhanced, a net propulsive force would result. We know that dark matter and negative energy are ubiquitous in this universe. Quantum fluctuations are more optimistic approach to get a picture of future propulsion technologies. For any of these concepts to work, there must be a real background medium in space. This medium must have a sufficiently large energy or mass density, must exist equally and isotropically across all space, and there must be a controllable means to alter the collisions with this medium to propel the vehicle. A high energy or mass density is required to provide sufficient radiation pressure or reaction momentum within a reasonable sail area. The requirement that the medium exist equally and isotropically across all space is to ensure that the propulsion device will work anywhere and in any direction in space. The requirement that there must be a controllable means to alter the collisions ensures that a controllable propulsive effect can be created.
The critical issues for both the sail and field drives have been compiled into the problem statement offered below. Simply put, a space drive requires some controllable and sustainable means to create asymmetric forces on the vehicle without expelling a reaction mass, and some means to satisfy conservation laws in the process. Regardless of which concept is explored, the following criteria must be satisfied.
(1) A mechanism must exist to interact with a property of space, matter, or energy which satisfies these conditions:
(a) must be able to induce an unidirectional acceleration of the vehicle.
(b) must be controllable.
(c) must be sustainable as the vehicle moves.
(d) must be effective enough to propel the vehicle.
(e) must satisfy conservation of momentum.
(f) must satisfy conservation of energy.
(2.1) If properties of matter or energy are used for the propulsive effect, this matter or energy…
(a) must have properties that enable conservation of momentum in the propulsive process.
(b) must exist in a form that can be controllably collected, carried, and positioned on the vehicle, or be controllably created on the vehicle.
(c) must exist in sufficiently high quantities to create a sufficient propulsive effect.
(2.2) If properties of space are used for the propulsive effect, these properties…
(a) must provide an equivalent reaction mass to conserve momentum.
(b) must be tangible; must be able to be detected and interacted with.
(c) must exist across all space and in all directions.
(d) must have a sufficiently high equivalent mass density within the span of the vehicle to be used as a propulsive reaction mass.
(e) must have characteristics that enable the propulsive effect to be sustained once the vehicle is in motion.
(3) The physics proposed for the propulsive mechanism and for the properties of space, matter, or energy used for the propulsive effect must be completely consistent with empirical observations.
Now it depend on us what kind of propulsion technology might be dispensable according to future needs.
[Ref: Challenge to Create the Space Drive by Millis M.]