Heisenberg... T-Shirt

In quantum physics, the Heisenberg uncertainty principle states that certain pairs of physical properties, like position and momentum, cannot both be known to arbitrary precision. That is, the more precisely one property is known, the less precisely the other can be known. It is impossible to measure simultaneously both position and velocity of a microscopic particle with any degree of accuracy or certainty. This is not only a statement about the limitations of a researcher's ability to measure particular quantities of a system, following the tenets of logical positivism, it is a statement about the nature of the system itself. In black, white and yes, even grey. Buy one, or not.