824 research outputs found
Quantum computation and the physical computation level of biological information processing
On the basis of introspective analysis, we establish a crucial requirement
for the physical computation basis of consciousness: it should allow processing
a significant amount of information together at the same time. Classical
computation does not satisfy the requirement. At the fundamental physical
level, it is a network of two body interactions, each the input-output
transformation of a universal Boolean gate. Thus, it cannot process together at
the same time more than the three bit input of this gate - many such gates in
parallel do not count since the information is not processed together. Quantum
computation satisfies the requirement. At the light of our recent explanation
of the speed up, quantum measurement of the solution of the problem is
analogous to a many body interaction between the parts of a perfect classical
machine, whose mechanical constraints represent the problem to be solved. The
many body interaction satisfies all the constraints together at the same time,
producing the solution in one shot. This shades light on the physical
computation level of the theories that place consciousness in quantum
measurement and explains how informations coming from disparate sensorial
channels come together in the unity of subjective experience. The fact that the
fundamental mechanism of consciousness is the same of the quantum speed up,
gives quantum consciousness a potentially enormous evolutionary advantage.Comment: 13 page
The quantum speed up as advanced knowledge of the solution
With reference to a search in a database of size N, Grover states: "What is
the reason that one would expect that a quantum mechanical scheme could
accomplish the search in O(square root of N) steps? It would be insightful to
have a simple two line argument for this without having to describe the details
of the search algorithm". The answer provided in this work is: "because any
quantum algorithm takes the time taken by a classical algorithm that knows in
advance 50% of the information that specifies the solution of the problem".
This empirical fact, unnoticed so far, holds for both quadratic and exponential
speed ups and is theoretically justified in three steps: (i) once the physical
representation is extended to the production of the problem on the part of the
oracle and to the final measurement of the computer register, quantum
computation is reduction on the solution of the problem under a relation
representing problem-solution interdependence, (ii) the speed up is explained
by a simple consideration of time symmetry, it is the gain of information about
the solution due to backdating, to before running the algorithm, a
time-symmetric part of the reduction on the solution; this advanced knowledge
of the solution reduces the size of the solution space to be explored by the
algorithm, (iii) if I is the information acquired by measuring the content of
the computer register at the end of the algorithm, the quantum algorithm takes
the time taken by a classical algorithm that knows in advance 50% of I, which
brings us to the initial statement.Comment: 23 pages, to be published in IJT
The quantum correlation between the selection of the problem and that of the solution sheds light on the mechanism of the quantum speed up
In classical problem solving, there is of course correlation between the
selection of the problem on the part of Bob (the problem setter) and that of
the solution on the part of Alice (the problem solver). In quantum problem
solving, this correlation becomes quantum. This means that Alice contributes to
selecting 50% of the information that specifies the problem. As the solution is
a function of the problem, this gives to Alice advanced knowledge of 50% of the
information that specifies the solution. Both the quadratic and exponential
speed ups are explained by the fact that quantum algorithms start from this
advanced knowledge.Comment: Earlier version submitted to QIP 2011. Further clarified section 1,
"Outline of the argument", submitted to Phys Rev A, 16 page
Levels of openness to Industry 4.0 and performance. An empirical analysis of manufacturing companies
Cosmic rays 10Be biennal data and their relationship to aurorae and sunspots
The galactic cosmic ray (C.R.) variations which should give information on three dimensional aspects of the heliospheric magnetic fields and on the solar wind, which modulate their influx into the Solar System were studied. In order to decode the information from the C.R. series it is necessary to know the mechanisms through which the modulation is produced. It it clear that a balance of effects with sources at different heliospheric latitudes results in the modulated C.R. intensity. It is found that the modulation of 10Be in polar ice may be due to at least two main contributions: (1) negative and in phase with the Solar flare activity modulating the cosmic ray flux in Forbush-type decreases, and (2) positive in phase with the appearance of large wind streams situated at both polar coronal holes. It is found that the high heliolatitude activity is related to a stable periodicity of 11.1y whereas the low heliolatitude activity contributes to the wondering of the solar cycles
Cosmic ray secular variations in terrestrial records and aurorae
The rediscovery that the Sun and the solar wind can undergo important changes on historical time scales has brought into question the stability of the cyclic behavior of past time series of solar and solar-terrestrial origin. It was found by Vector Fourier analysis that the solar 11 year cycle is present in the series of 10Be, delta 180, in ice cores and of thermoluminescence (TL) in sea sediments during the last Millennia with a frequency modulation, related to the Sun behavior, as tested by comparison with the Sunspot number R sub z series. It was shown that the cyclogram of the series of yearly Aurorae from 1721 to 1979 linear-regression-corrected-for-R sub z is straight for the periodicity zeta=11,1y, which indicates that such periodicity is constant in time corresponding to the only line present in the 11y band. The maxima of this component appear at the same time together with the high speed solar wind streams taking place in coronal holes situated in high heliolatitudes. It is evidenced that the 11 year cycle has undergone frequency oscillations on a time scale of two centuries, although it is very difficult to determine the periodicities with high accuracy
The 50% advanced information rule of the quantum algorithms
The oracle chooses a function out of a known set of functions and gives to
the player a black box that, given an argument, evaluates the function. The
player should find out a certain character of the function through function
evaluation. This is the typical problem addressed by the quantum algorithms. In
former theoretical work, we showed that a quantum algorithm requires the number
of function evaluations of a classical algorithm that knows in advance 50% of
the information that specifies the solution of the problem. Here we check that
this 50% rule holds for the main quantum algorithms. In the structured
problems, a classical algorithm with the advanced information, to identify the
missing information should perform one function evaluation. The speed up is
exponential since a classical algorithm without advanced information should
perform an exponential number of function evaluations. In unstructured database
search, a classical algorithm that knows in advance 50% of the n bits of the
database location, to identify the n/2 missing bits should perform Order(2
power n/2) function evaluations. The speed up is quadratic since a classical
algorithm without advanced information should perform Order(2 power n) function
evaluations. The 50% rule identifies the problems solvable with a quantum sped
up in an entirely classical way, in fact by comparing two classical algorithms,
with and without the advanced information.Comment: 18 pages, submitted with minor changes to the International Journal
of Theoretical Physic
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