58
PHVS1CS OF THE IMPOSSIBLE
and to extract precise predictions for these energy levels that fit the
data perfectly.
But there was still a nagging question that haunts physics even today. If the electron is described by a wave, then what is waving? This
has been answered by physicist Max Born, who said that these waves
are actually waves of probability. These waves tell you only the chance
of finding a particular electron at any place and any time. In other
words, the electron is a particle, but the probability of finding that particle is given by Schrodinger's wave. The larger the wave, the greater
the chance of finding the particle at that point.
With these developments, suddenly chance and probability were
being introduced right into the heart of physics, which previously had
given us precise predictions and detailed trajectories of particles, from
planets to comets to cannon balls.
This uncertainty was finally codified by Heisenberg when he proposed the uncertainty principle, that is, the concept that you cannot
know both the exact velocity and the position of an electron at the
same time. Nor can you know its exact energy, measured over a given
amount of time. At the quantum level all the basic laws of common
sense are violated: electrons can disappear and reappear elsewhere,
and electrons can be many places at the same time.
(Ironically, Einstein, the godfather of the quantum theory who
helped to start the revolution in 1905, and Schrôdinger, who gave us
the wave equation, were horrified by the introduction of chance into
fundamental physics. Einstein wrote, "Quantum mechanics calls for a
great deal of respect. But some inner voice tells me that this is not the
true Jacob. The theory offers a lot, but it hardly brings us any closer to
the Old Man's secret. For my part, at least, I am convinced that He
doesn't throw dice.")
Heisenberg's theory was revolutionary and controversial-but it
worked. In one sweep, physicists could explain a vast number of puzzling phenomena, including the laws of chemistry. To impress my
Ph.D.
students with just how bizarre the quantum theory is, I sometimes ask them to calculate the probability that their atoms will suddenly dissolve and reappear on the other side of a brick wall. Such a
PHVS1CS OF THE IMPOSSIBLE
and to extract precise predictions for these energy levels that fit the
data perfectly.
But there was still a nagging question that haunts physics even today. If the electron is described by a wave, then what is waving? This
has been answered by physicist Max Born, who said that these waves
are actually waves of probability. These waves tell you only the chance
of finding a particular electron at any place and any time. In other
words, the electron is a particle, but the probability of finding that particle is given by Schrodinger's wave. The larger the wave, the greater
the chance of finding the particle at that point.
With these developments, suddenly chance and probability were
being introduced right into the heart of physics, which previously had
given us precise predictions and detailed trajectories of particles, from
planets to comets to cannon balls.
This uncertainty was finally codified by Heisenberg when he proposed the uncertainty principle, that is, the concept that you cannot
know both the exact velocity and the position of an electron at the
same time. Nor can you know its exact energy, measured over a given
amount of time. At the quantum level all the basic laws of common
sense are violated: electrons can disappear and reappear elsewhere,
and electrons can be many places at the same time.
(Ironically, Einstein, the godfather of the quantum theory who
helped to start the revolution in 1905, and Schrôdinger, who gave us
the wave equation, were horrified by the introduction of chance into
fundamental physics. Einstein wrote, "Quantum mechanics calls for a
great deal of respect. But some inner voice tells me that this is not the
true Jacob. The theory offers a lot, but it hardly brings us any closer to
the Old Man's secret. For my part, at least, I am convinced that He
doesn't throw dice.")
Heisenberg's theory was revolutionary and controversial-but it
worked. In one sweep, physicists could explain a vast number of puzzling phenomena, including the laws of chemistry. To impress my
Ph.D.
students with just how bizarre the quantum theory is, I sometimes ask them to calculate the probability that their atoms will suddenly dissolve and reappear on the other side of a brick wall. Such a