What is the matter:

Ironically the most illusive and least known entity in the universe is the most abundant one namely matter itself, this basic building block of the universe, the study of which has been with us for over a century, is today more mysterious, complex and illusive that ever before bringing the paraphrase "the more you learn the less you know" to mind. Matter is us and everything else, but while its abundance and accessibility, unlike the stars and galaxies, make its stringent scrutiny possible, its esoteric characteristics preempt progress and impede insight to the point of more questions than answers with every step forward.
More than its components, it is the perpetual uncertainties within the atom that expresses its behavior as a set of probabilities. The study of neutrinos, if and when captured and examined for properties and mass will no doubt shed more light upon the whole phenomenon of matter. An excellent underground observatory for the study of the neutrinos was recently opened at Sudbury Ont. in Canada (Sudbury Neutrino Observatory-SNO) which will no doubt facilitate the understanding of these incredibly minute solar emmissions by studying their characteristics.
But there is more, the predictions of quantum mechanics as applied to subatomic particles defies common sense, it suggests that a change in an object in one place can instantly produce a change in a related object elsewhere in the universe.In a historic dual between common sense and quantum mechanic, the latter beat the former by a spin (experiment conducted by clause/freedman-Berkeley).