Heisenberg uncertainty principle. As I understand this, it refers to how, at a quantum level, it is actually impossible to know everything about the state of the particles that make up the universe. The popular explanation I once heard on the radio is to imagine a photograph of a bullet in flight. You can either fire a very short flash, and catch the bullet frozen in time and know a great deal about the position of the bullet, or you can take a longer exposure, get a smeared picture of the bullet, from which you can accurately calculate the bullet's speed.
The uncertainty principle says that, the more you know about one state, for example the speed, the less certain you are about another state, in this case the position. There is a certain amount of uncertainty built into the very way space and time are put together.
Scientists do not throw their hands up in despair and walk away. Instead they are humble. The understand that the notions of "speed" and "position" are linked, and are really just a useful way to talk about an object, but aren't really inherent in the object. If they insist on talking about an object as having a measurable position, they accept that they are therefore going to be uncertain as to its speed.
I think this would make a great metaphor for a life of faith. As we study the quantum components that make up this life, we find things tied together in odd dual systems. Further we find that the more we say with certainty about one side of the duality, the less we seem to know about the other. Are we predestined, or do we choose to follow God of our own free will? Is it more important to do the right things or to believe the right things? Is God an unchanging everlasting being or an active and creative force?
The classic remedy for this has been to try and find the "balanced" viewpoint. From which one can speak with equal certainty about both sides. As I have said before, this type of approach always drives me nuts, because I don't see Jesus as a lover of careful balance. He seems to me to be constantly taking people's balanced ideas and unbalancing them in wild and unexpected ways.
With apologies if I am mis-using this, it seems to me that we need the humility that the uncertainty principle enforces. The very particles that make up all of creation, enforce some mystery, some unknowing. Can it be a surprise then that a study of the creator yields the same results.
The title of this post refers to device built into the transporters in the Star Trek universe, the "Heisenberg Compensators", which are mentioned a few times as a way of explaining / not explaining how reliable matter transmitters could be built given the Heisenberg uncertainty principle. "No problem", thought the scriptwriter, we'll just add a "Heisenberg compensator" to the transporter. This is of course ridiculous. Maybe a "Systematic Theology" is the "Heisenberg Compensator" of faith.