>You are likely correct as there is a flow of, what astronomers think is dark or anti matter past the edge of the universe. If it is anti matter then there is a huge flash of light beyond the range of our technology or the light cannot escape from the area that is moving galaxies at two million miles an hour towards whatever it happens to be. Here's a link
http://www.msnbc.msn.com/id/26857495/Note that antimatter and dark matter are two quite different things. Antimatter is a collection of antiparticles: antiprotons (similar to protons, but with a negative charge), positrons or anti-electrons (positive charge), anti-neutrons (opposite to normal neutrons in some other aspect than charge), etc. Antimatter gets destroyed on contact with "normal" matter. It is yet a mystery why the Universe seems to be dominated by normal matter, but it is believed - and in part observed - that the symmetry between matter and antimatter is not 100% perfect.
Dark matter is a substance that doesn't interact at all, or that hardly interacts, with light, etc., and almost only interacts through gravitation. It is not yet known what it is made of, but it is definitely not normal matter, and not antimatter either (due to its similarities with normal matter). It is merely known to exist, due to its gravitational effects.
Difference in opinions hath cost many millions of lives: for instance, whether flesh be bread, or bread be flesh; whether whistling be a vice or a virtue; whether it be better to kiss a post, or throw it into the fire... (from Gulliver's Travels)