This morning I was listening to Brian Greene on the Point of Inquiry podcast and came up with a hypothesis that may effectively test psychic abilities to a very high degree of certainty. I hasten to add that I am highly skeptical of the claims surrounding psychic abilities, but like a good skeptic, I leave open the possibility that even outlandish claims may someday find experimental support.
If you have studied quantum physics, or even higher level chemistry, you are familiar with the "Uncertainty Principle" and "Quantum Superposition". In a nutshell, these ideas say that a particle can exhibit the property of superposition, which is a complicated sounding way of saying that a particle can be in multiple states at the same time (like being alive and dead at the same time). Once this superposed particle is measured or otherwise observed, it "chooses" one state or the other (the technical term for "choosing" is known as "collapsing the wave function"). Yes, these ideas may seem counter intuitive, but there is nearly a century of experimental evidence backing this up. You can also do the experiment yourself if you are still unconvinced (science is cool that way).
Given that a person with psychic abilities claims to be able to see and control things outside of the realm of normal senses, we should be able to apply the Uncertainty Principle and Quantum Superposition to this claim.
Thus my hypothesis would be worded as follows:
"A person with psychic abilities should be able to collapse the wave function of unobserved particles."
This hypothesis implies a certain contradiction - how do you maintain the wave function (a.k.a. the superposed state) of a particle and still observe it? Given that particles have been observed in their superposed state, our hypothesis could possibly be tested by repeating those experiments in the presence of a psychic. If the psychic is indeed causing the collapse of the wave function in the unobserved particles, the experiments would fail to replicate in a reliable fashion as there would be no superposed state to observe.
All that being said, if you really are convinced that you have psychic abilities, there is an easy $1 Million waiting for you...