To make a long story short, Bishop Berkeley argued that the idea of matter existing independently of perception was incoherent, since the properties of matter are (or were in Berkeley's time) defined in perceptual terms such as hardness, redness, etc. Hence, Berkeley's conclusion that "to be is to be perceived."

Of course, Berkeley knew that there is a world beyond human perception, but since he argues that being is being perceived, he concluded that there is a Great Perceiver, God, responsible for what we call the external world.

Thus, Berkeley's argument addresses two major philosophical issues: the problem of the thing in itself (solution: there is none) and the existence of God (there must be one in order for the external world to exist).

However, modern physics has led to a description of matter that--it seems to me--need not reference perceptual properties at all. In fact, matter has properties that not only lie beyond our perception, but literally can't be imagined in perceptual terms--mass, charge, "charm," "strangeness," (the latter two being names for properties of subatomic particles), and more.

Has physics thus undermined Berkeley's idealism, or has it merely prompted refinements in the arguments of the few modern idealists?