Quantum Loup
Garou
In 1927, Werner Heisenberg
declared it impossible to measure both the velocity and location of any
subatomic particle. The explanation seemed simple enough: the light needed
to see a subatomic particle gave the tiny mote more energy and knocked it
somewhere else before the photons showing where it had been reached the
observer's eye. Heisenberg called this the Uncertainty Principle. And Einstein
didn't like it. He came up with all kinds of clever experiments to disprove
it.
In a thought experiment, Einstein
filled a box on a scale with a radioactive substance that emitted radiation
randomly. The shutter of the box opened and quickly shut, timed by a precise
clock, so that some radiation escaped. In this way, he determined with accuracy
the time the energy got out and how much the box weighed before and after.
His famous E = MC2 equivalence of mass and energy allowed him to calculate
exactly how much energy was left in the box. Ta-da! He had measured both
the location and the velocity of the escaping radiation and had disproved
the Uncertainty Princple!
But he was wrong. His own theory
of relativity proved him wrong. Once the energy left the box, the box got
lighter and rose slightly on the measuring scale. That altered the position
of the clock and immediately put the box in a different reference frame.
Einstein's principle of relativity insists that a set of measurements depends
on an observer's particular frame of reference, and so the clock's measurement
of time was different before and after the energy escaped - and that resulted
in an inevitable margin of error. Experiments verified, in fact, that the
imprecision equaled the specific uncertainty predicted by Heisenberg's equation!
Like it or not, Einstein had
to accept that, on a fundamental level, the physical universe does not have
a definite form but exists as uncertainty - a reality of probabilities,
potentials, and pure chance. That is why he said, "I cannot believe
that God would choose to play dice with the universe."
Neils Bohr, a fellow quantum
physicist responded, "Einstein, don't tell God what to do."
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