Information Technology Reference
In-Depth Information
I
NTRODUCTION
Moore's law describes the trend of computing hardware, in which the performance of the
microprocessor has doubled every two years as shown in Figure 1. But It is widely believed
that Moore's law for microprocessor performance will fail to hold in the next decade due to
the brick wall arising from fundamental physical limitations of the computational process.
Figure 1. Logic gate in the PC (A) and the Moore's law (B).
Instead of conventional computer systems, a quantum computer would store information
as either 1 and 0, or a quantum superposition of the two states. Such a "quantum bit," called a
qubit, allows for far greater flexibility than the binary system of conventional computers.
Specifically, it is considered that a quantum computer would be able to perform calculations
on a far greater order of magnitude than traditional computers.
However, R.Feynman[1986] discussed the possibility of a quantum computer by taking
an example of reversible computing in his paper and he pointed that computational energy
cost versus speed was limited by the energy dissipation during computation. According to
Feynman's idea, the computational speed is limited by minimum energy required to transport
a bit of information irreversibly between two devices, which prevents the speeding up of
quantum computation.
From the assumption that the evanescent photon is a superluminal particle called a
tachyon, the author studies the possibility of realization of a high performance computing
system by utilizing superluminal evanescent photons and he has also studied the possibility
that the microtubular structure of neurons in a human brain is functioning as a quantum
computational system that can attain higher efficient computation compared with
conventional silicon processors.
