I really should avoid these discusions, but I can't help myself. According to current quantum field theories (and these have been verified by experiment to a huge number of decimal places' quantum electrodynamics is probably the most experimentally verified of all physical theories), the vacuum isn't really empty, but is actually filled with countless "virtual" particles, continually popping into and then out of existence. The Heisenberg (sp?) Uncertainty principle in one of its many forms states that there is an upper limit to measurements of the uncertainties of the energy of a particle and the time interval in which it is measured. For very bried time intervals, it is perfecty possible for a photons to materialize out of nothingness (in pairs, spin is conserved), as long as they dissappear within that same time interval. Sounds crazy, but these virtual photons have real affects that can be measured. Dan C. At 05:34 PM 26-10-02 -0400, Brian Blankenship wrote: >Mater is made up of energy, ALL mater, that includes air. Inbetween the >electron cloud and the atomic center is void, nothing. Now there are of >course other types of sub-atomic particles like neutrinos, but there is no >"mater" like air between them. Air is mater, made up of these tiny atomic >structures. >