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Brain neurons as quantum computers: {\it in vivo} support of background physics  [PDF]
A. Bershadskii,E. Dremencov,J. Bershadskii,G. Yadid
Quantitative Biology , 2003, DOI: 10.1142/S0129183103005030
Abstract: The question: whether quantum coherent states can sustain decoherence, heating and dissipation over time scales comparable to the dynamical timescales of the brain neurons, is actively discussed in the last years. Positive answer on this question is crucial, in particular, for consideration of brain neurons as quantum computers. This discussion was mainly based on theoretical arguments. In present paper nonlinear statistical properties of the Ventral Tegmental Area (VTA) of genetically depressive limbic brain are studied {\it in vivo} on the Flinders Sensitive Line of rats (FSL). VTA plays a key role in generation of pleasure and in development of psychological drug addiction. We found that the FSL VTA (dopaminergic) neuron signals exhibit multifractal properties for interspike frequencies on the scales where healthy VTA dopaminergic neurons exhibit bursting activity. For high moments the observed multifractal (generalized dimensions) spectrum coincides with the generalized dimensions spectrum calculated for a spectral measure of a {\it quantum} system (so-called kicked Harper model, actively used as a model of quantum chaos). This observation can be considered as a first experimental ({\it in vivo}) indication in the favour of the quantum (at least partially) nature of the brain neurons activity.
Chance, Choice, and Consciousness: The Role of Mind in the Quantum Brain  [PDF]
Henry P. Stapp
Physics , 1995,
Abstract: Contemporary quantum mechanical description of nature involves two processes. The first is a dynamical process governed by the equations of local quantum field theory. This process is local and deterministic, but it generates a structure that is not compatible with observed reality. A second process is therefore invoked. This second process somehow analyzes the structure generated by the first process into a collection of possible observable realities, and selects one of these as the actually appearing reality. This selection process is not well understood. It is necessarily nonlocal and, according to orthodox thinking, is governed by an irreducible element of chance. The occurrence of this irreducible element of chance means that the theory is not naturalistic: the dynamics is controlled in part by something that is not part of the physical universe. The present work describes a quantum mechanical model of brain dynamics in which the quantum selection process is a causal process governed not by pure chance but rather by a mathematically specified nonlocal physical process identifiable as the conscious process.
Quantum theory and consciousness: an overview with selected examples  [PDF]
Harald Atmanspacher
Discrete Dynamics in Nature and Society , 2004, DOI: 10.1155/s102602260440106x
Abstract: It is widely accepted that consciousness or, in other words, mental activity is in some way correlated to the behavior of the brain or, in other words, material brain activity. Since quantum theory is the most fundamental theory of matter that is currently available, it is a legitimate question to ask whether quantum theory can help us to understand consciousness. Several approaches answering this question affirmatively, proposed in recent decades, will be surveyed. It will be pointed out that they make different epistemological assumptions, refer to different neurophysiological levels of description, and adopt quantum theory in different ways. For each of the approaches discussed, these imply both problematic and promising features which will be indicated.
Quantum Computers  [PDF]
Archil Avaliani
Computer Science , 2004,
Abstract: This research paper gives an overview of quantum computers - description of their operation, differences between quantum and silicon computers, major construction problems of a quantum computer and many other basic aspects. No special scientific knowledge is necessary for the reader.
Notes on Quantum Mechanics and Consciousness  [PDF]
Elemer E Rosinger
Physics , 2005,
Abstract: There have lately been a variety of attempts to connect, or even explain, if not in fact, reduce human consciousness to quantum mechanical processes. Such attempts tend to draw a sharp and fundamental distinction between the role of consciousness in classical mechanics, and on the other hand, in quantum mechanics, with an insistence on the assumed exceptional character of the latter. What is strangely missed, however, is the role of human consciousness as such in the very discovery or creation of both of these physical theories. And this a priori role is far more important than all the possible a posteriori interplays between consciousness and the mentioned two theories of physics, interplays which may happen during one or another specific experiment, measurement, and so on. In this regard it is suggested that the specific features human consciousness may exhibit during interactions with quantum mechanical systems may as well have other explanations which do not appear to be less plausible, or less well founded.
Quantum Physics and Computers  [PDF]
Adriano Barenco
Physics , 1996, DOI: 10.1080/00107519608217543
Abstract: Recent theoretical results confirm that quantum theory provides the possibility of new ways of performing efficient calculations. The most striking example is the factoring problem. It has recently been shown that computers that exploit quantum features could factor large composite integers. This task is believed to be out of reach of classical computers as soon as the number of digits in the number to factor exceeds a certain limit. The additional power of quantum computers comes from the possibility of employing a superposition of states, of following many distinct computation paths and of producing a final output that depends on the interference of all of them. This ``quantum parallelism'' outstrips by far any parallelism that can be thought of in classical computation and is responsible for the ``exponential'' speed-up of computation. This is a non-technical (or at least not too technical) introduction to the field of quantum computation. It does not cover very recent topics, such as error-correction.
The Heisenberg Representation of Quantum Computers  [PDF]
Daniel Gottesman
Physics , 1998,
Abstract: Since Shor's discovery of an algorithm to factor numbers on a quantum computer in polynomial time, quantum computation has become a subject of immense interest. Unfortunately, one of the key features of quantum computers - the difficulty of describing them on classical computers - also makes it difficult to describe and understand precisely what can be done with them. A formalism describing the evolution of operators rather than states has proven extremely fruitful in understanding an important class of quantum operations. States used in error correction and certain communication protocols can be described by their stabilizer, a group of tensor products of Pauli matrices. Even this simple group structure is sufficient to allow a rich range of quantum effects, although it falls short of the full power of quantum computation.
The dissipative brain  [PDF]
Giuseppe Vitiello
Quantitative Biology , 2004,
Abstract: I review the dissipative quantum model of brain and discuss its recent developments related with the role of entanglement, quantum noise and chaos. Some comments on consciousness in the frame of the dissipative model are also presented. Dissipation seems to account for the medial character of consciousness, for its being in the present (the Now), its un-dividable unity, its intrinsic subjectivity (autonomy). Finally, essential features of a conscious artificial device, if ever one can construct it, are briefly commented upon, also in relation to a device able to exhibit mistakes in its behavior. The name I give to such a hypothetical device is Spartacus.
Possibility to Realize the Brain-Computer Interface from the Quantum Brain Model Based on Superluminal Particles  [PDF]
Takaaki Musha, Toshiki Sugiyama
Journal of Quantum Information Science (JQIS) , 2011, DOI: 10.4236/jqis.2011.13015
Abstract: R. Penrose and S. Hameroff have proposed an idea that the brain can attain high efficient quantum computation by functioning of microtubular structure of neurons in the cytoskelton of biological cells, including neurons of the brain. But Tegmark estimated the duration of coherence of a quantum state in a warm wet brain to be on the order of 10>–13
Non-local quantum evolution of entangled ensemble states in neural nets and its significance for brain function and a theory of consciousness  [PDF]
Erhard Bieberich
Physics , 1999,
Abstract: Current quantum theories of consciousness suggest a configuration space of an entangled ensemble state as global work space for conscious experience. This study will describe a procedure for adjustment of the singlet evolution of a quantum computation to a classical signal input by action potentials. The computational output of an entangled state in a single neuron will be selected in a network environment by "survival of the fittest" coupling with other neurons. Darwinian evolution of this coupling will result in a binding of action potentials to a convoluted orbit of phase-locked oscillations with harmonic, m-adic, or fractal periodicity. Progressive integration of signal inputs will evolve a present memory space independent from the history of construction. Implications for mental processes, e.g., associative memory, creativity, and consciousness will be discussed. A model for the generation of quantum coherence in a single neuron will be suggested.
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