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**Figure 2:** Though he formulated its fundamental equation, Schrödinger was
one of quantum theory's most acerbic critics.

**Figure 3:** For Einstein, Schrödinger's cat, or the measurement problem, was
no paradox. Rather, it merely demonstrated that the wave function does not
provide a complete description of physical reality, for [8, page
671,] ``If we attempt [to work with] the interpretation that the
quantum-mechanical description is to be understood as a complete
description of the individual system, we are forced to the interpretation
that the location of the mark on the strip [or the fact as to whether the
cat is dead or alive] is nothing which belongs to the system *per
se,* but that the existence of that location is essentially dependent
upon the carrying out of an observation made on the
registration-strip. Such an interpretation is certainly by no means absurd
from a purely logical standpoint; yet there is hardly likely to be anyone
who would be inclined to consider it seriously.''

**Figure 4:** The leading figures of twentieth century physics, Einstein and
Bohr engaged in a decades-long debate about the meaning and interpretation
of quantum mechanics.

**Figure 5:** Over the past half century, Murray Gell-Mann has been one of the
most sensible critics of orthodox quantum theory while Richard Feynman was
one of its most sensible defenders.

**Figure 6:** For the past several decades, John Bell was the deepest
thinker on the foundations of quantum mechanics. His analysis of
nonlocality and hidden variables revitalized the field. Unfortunately, the
implications of his work have been widely misunderstood.

**Figure 7:** The participants of the Fifth Solvay Congress

**Figure 8:** Some of David Bohm's ideas about quantum mechanics and the nature
of physical reality, for example regarding the implicate order, were rather
speculative, but his deterministic version of quantum mechanics is quantum
theory's most lucid and straightforward completion.

Wed Aug 13 17:22:41 EDT 1997