Supplement date: 20 December 2008
Light is what we call radiant electromagnetic energy. It originates in the acceleration of charged particles. such as electrons. These parent particles may be either bound, as in an atom, or free, as in space. Once it exists, light propagates at a velocity that is controlled by the ambient medium. We routinely slow it down from its in-vacuum speed by causing it to pass through media such as glass. We are here concerned with its speed in the hard vacuum we know as interstellar space. When our spaceship exposes its antimatter core to interstellar space, the value of c is increased in the immediate vicinity of the spaceship. It is often said that the speed of light is given by a combination of atomic constants, such as the charge and mass of the electron. However, the question arises, what electrons? In interstellar space, there are very few electrons in the light years that yawn between most stars.
That speed (usually written as c) has a numerical value of approximately 300,000 km/sec (more precisely, its average value is 299,792.4562 kilometers per second. This speed is presently far greater than that of any spacecraft in existence. C is widely believed to be one of nature's physical constants. The reason for this belief goes back to a series of brilliant measurements made by Albert Michelson and Edward Morley that extended back to the year 1887. Others confirmed their result.
However, all of the universe is pervaded by gravity; no shield against gravity is known. This “gravity” controls the curvature of spacetime everywhere. (This is equivalent to saying that the force of gravity is given everywhere by the local curvature.) Each point in spacetime is the vector sum of all the gravitational fields of masses, both normal and antimatter masses, and both local and distant. In particular, our region of spacetime has a curvature determined practically completely by the mass of the Sun. The “solar neighborhood” referred to in this blog extends to huge distances. All of the system’s objects, even objects beyond Pluto, execute orbital motion about the Sun. This means that c is fixed in our neighborhood by the mass of the Sun. The principal reason that c is the 300,000 km/sec value that it is, is that the mass of the Sun is what it is. That is, the number of atoms in the Sun, together with their composition, determines c in the neighborhood of the Sun. The Sun is composed of normal matter; its occasional coronal mass ejections do not result in subsequent flares of annihilation gamma radiation at Earth, when the solar particles encounter Earth's atmosphere.
Secular Variability of c
As the Sun consumes its thermonuclear fuel in its core, energy is generated. This energy eventually makes its way out to the solar surface and then escapes into space as sunlight. Using Einstein’s relation of mass and energy, this means that the solar mass decreases with time, slowly decreasing the local curvature of spacetime and hence our value of c.
Neglecting the relatively small solar motions induced by the motions of the planets, the Sun is not motionless. Carrying Earth and all the other planets with it, the Sun is executing a gravitational orbit about the Galactic central region. As it does so, we approach and recede from other stars, stars that are also partaking of the general Galactic revolution. Therefore the gravity – induced curvature of spacetime changes, presumably causing the speed of light to change; c itself varies in time. Admittedly, this Galactic change is slow by human standards: about a quarter of a billion years is required in order to complete one full revolution.
WARNING: EXTREME DANGER
In addition to offering humanity a possible means of salvation, antimatter is unquestionably the most dangerous substance that we have ever encountered. Antimatter must never be touched by human hands. Even worse, it must never touch any matter which had its origin on earth, or even anywhere in the solar system. If these conditions are violated, the antimatter will violently annihilate the normal matter; An incredibly great explosion will result, an explosion whose magnitude dwarfs, if not trivializes, the largest thermonuclear explosion ever planned. The precise energy yield will depend on the mass of the antimatter involved. The only way to handle antimatter is VERY CAREFULLY and remotely, through the use of magnetic fields. The magnetic fields will most likely require the use of superconducting coils. If coolant is required for the superconductors, its supply MUST never fail.