Ultimate computing Limit
Is Moor's observation on computing reaching its Limit?
what are options ? parallel computing or Quantum computers?
what is ultimate computing limit? which physics laws govern the same
Information is physical,” was a favorite statement of Landauer a researcher at IBM, to emphasize that the processing
of information by a computer is constrained by the laws of physics. Three known constraints
are:
• Einstein’s constraint: Information cannot be transferred at a speed greater than
the speed of light c.
• Landauer’s constraint [3]: Information cannot be erased without generating heat:
the minimum heat production is kT ln 2 per erased bit of information, at a temperature
T.
• Margolus & Levitin’s constraint [4]: Information cannot be processed at a rate
exceeding 4E/h operations per second, for an available energy E.
Together, these three constraints represent three major frame works of theoretical physics:
Respectively, the theory of relativity, statistical mechanics, and quantum mechanics.
Each constraint is governed by one of the fundamental constants of nature
Together, these three constraints represent three major frame works of theoretical physics:
Respectively, the theory of relativity, statistical mechanics, and quantum mechanics.
Each constraint is governed by one of the fundamental constants of nature
The speed
2
of light c = 2.98 x 10,0000000
m/s, Boltzmann’s constant k = 1.4 x10−23 Joule/Kelvin, and
Planck’s constant h = 6.6 x10−34 Joule/Hertz.
The most powerful computers available today operate far below these ultimate limits,
but this may change at some point in the future. The field of quantum computation aims
at constructing a computer that actually reaches the fundamental limits on information
transfer, erasure, and processing