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P H V SIC S OF THE IMPOSSIBLE
The wonders of the modern age, such as lasers, the Internet, computers, TV, cell phones, radar, microwave ovens, and so forth, are all
based on the shifting sands of probabilities.
The sharpest example of this conundrum is the famous "Schrodinger's cat" problem (formulated by one of the founders of the quantum theory, who paradoxically proposed the problem in order to
smash this probabilistic interpretation). Schrôdinger railed against
this interpretation of his theory, stating, "If one has to stick to this
damned quantum jumping, then I regret having ever been involved in
this thing."
The Schrodinger's cat paradox is as follows: a cat is placed in a
sealed box. Inside a gun is pointed at the cat (and the trigger is then
connected to a Geiger counter next to a piece of uranium). Normally
when the uranium atom decays it sets off the Geiger counter and then
the gun and the cat is killed. The uranium atom can either decay or
not. The cat is either dead or alive. This is just common sense.
But in the quantum theory, we don't know for sure if the uranium
has decayed. So we have to add the two possibilities, adding the wave
function of a decayed atom with the wave function of an intact atom.
But this means that, in order to describe the cat, we have to add the two
states of the cat. So the cat is neither dead nor alive. It is represented
as the sum of a dead cat and a live cat!
As Feynman once wrote, quantum mechanics "describes nature as
absurd from the point of view of common sense. And it fully agrees
with experiment. So I hope you can accept nature as She is-absurd."
To Einstein and Schrôdinger, this was preposterous. Einstein believed in "objective reality," a commonsense, Newtonian view in
which objects existed in definite states, not as the sum of many possible states. And yet this bizarre interpretation lies at the heart of modern civilization. Without it modern electronics (and the very atoms of
our body) would cease to exist. (In our ordinary world we sometimes
joke that it's impossible to be "a little bit pregnant." But in the quantum
world, it's even worse. We exist simultaneously as the sum of all possible bodily states: unpregnant, pregnant, a child, an elderly woman, a
teenager, a career woman, etc.)
P H V SIC S OF THE IMPOSSIBLE
The wonders of the modern age, such as lasers, the Internet, computers, TV, cell phones, radar, microwave ovens, and so forth, are all
based on the shifting sands of probabilities.
The sharpest example of this conundrum is the famous "Schrodinger's cat" problem (formulated by one of the founders of the quantum theory, who paradoxically proposed the problem in order to
smash this probabilistic interpretation). Schrôdinger railed against
this interpretation of his theory, stating, "If one has to stick to this
damned quantum jumping, then I regret having ever been involved in
this thing."
The Schrodinger's cat paradox is as follows: a cat is placed in a
sealed box. Inside a gun is pointed at the cat (and the trigger is then
connected to a Geiger counter next to a piece of uranium). Normally
when the uranium atom decays it sets off the Geiger counter and then
the gun and the cat is killed. The uranium atom can either decay or
not. The cat is either dead or alive. This is just common sense.
But in the quantum theory, we don't know for sure if the uranium
has decayed. So we have to add the two possibilities, adding the wave
function of a decayed atom with the wave function of an intact atom.
But this means that, in order to describe the cat, we have to add the two
states of the cat. So the cat is neither dead nor alive. It is represented
as the sum of a dead cat and a live cat!
As Feynman once wrote, quantum mechanics "describes nature as
absurd from the point of view of common sense. And it fully agrees
with experiment. So I hope you can accept nature as She is-absurd."
To Einstein and Schrôdinger, this was preposterous. Einstein believed in "objective reality," a commonsense, Newtonian view in
which objects existed in definite states, not as the sum of many possible states. And yet this bizarre interpretation lies at the heart of modern civilization. Without it modern electronics (and the very atoms of
our body) would cease to exist. (In our ordinary world we sometimes
joke that it's impossible to be "a little bit pregnant." But in the quantum
world, it's even worse. We exist simultaneously as the sum of all possible bodily states: unpregnant, pregnant, a child, an elderly woman, a
teenager, a career woman, etc.)