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Hameroff and Penrose went on to develop an elaborate concept of consciousness.
Underlying their concept is the Heisenberg proposal that probability waves have a
reality of their own and are not just a way to explain the results of experimental
observations. Hameroff and Penrose developed what they term orchestrated objec-
tive reduction (ORCHOR), a sort of spontaneous observation, after which the results
of quantum-level calculations are manifest. A full explanation of ORCH OR may be
found in the references.
Requirements for Quantum Computations
To have a quantum computer there are basic requirements [
11
,
12
] as listed in
Table
9.1
.
Requirement 1
Quantum information must be represented in a quantum system: To represent
quantum information, particles must be part of a quantum system with regular
quantum states.
Trapped ions can constitute a quantum system, but only if reduced in tempera-
ture to minimize the interference of thermal vibration. They work with the lowest
levels of phonons (vibrational states) so that it is possible to access the hyperfine
spin states, that is, electron plus nuclear spin combinations. Quantum computers
with only a few qubits have been implemented as proof of the quantum principle
(but not as a practical system).
Ions in an ion trap interact via a shared vibrational or phonon state. States may be
individually transformed and they may be controlled by other states using laser
beams tuned exactly to specific frequencies, that is, specific excitation energies.
Using such methods, a controlled toggle (NOT) operation has been demonstrated in
the laboratory.
For readout, a laser process creates fluorescence that is easily analyzed, and
whose intensity is proportional to the probability of a qubit being in a zero state.
This process is effectively repeated for selected states to infer the states of the
qubits involved. Many thousands of laser-observe cycles are possible, giving
accurate measurements.
Table 9.1
Requirements for quantum computation
There must be a quantum system
Initialization of the system must be possible
Quantum information within the system must be appropriately transformable
Useful information must be available to the outside world
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