23,045 research outputs found
Quantum Dissipation due to the Interaction with Chaos
We discuss the possibility of having "quantum dissipation" due to the
interaction with chaotic degrees of freedom. We define the conditions that
should be satisfied in order to have a dissipative effect similar to the one
due to an interaction with a (many body) bath. We also compare with the case
where the environment is modeled by a random matrix model. In case of
interaction with "chaos" we observe a regime where the relaxation process is
non-universal, and reflects the underlaying semiclassical dynamics. As an
example we consider a two level system (spin) that interacts with a two
dimensional anharmonic oscillator.Comment: 5 pages, 1 figure, final improved version, to be published as Phys
Rev. E Rapid Communicatio
Culture and Cancer
Genetic mechanisms, since they broadly involve information
transmission, should be translatable into information dynamics formalism. From this perspective we reconsider the adaptive mutator, one possible means of 'second order selection' by which a highly structured 'language' of environment and development writes itself onto the variation upon which evolutionary selection and tumorigenesis operate. Our approach uses recent results in the spirit of the Large Deviations Program of applied probability that permit transfer of phase transition approaches from statistical mechanics to information theory, generating evolutionary and developmental punctuation in what we claim to be a highly natural manner
Computing with cells: membrane systems - some complexity issues.
Membrane computing is a branch of natural computing which abstracts computing models from the structure and the functioning of the living cell. The main ingredients of membrane systems, called P systems, are (i) the membrane structure, which consists of a hierarchical arrangements of membranes which delimit compartments where (ii) multisets of symbols, called objects, evolve according to (iii) sets of rules which are localised and associated with compartments. By using the rules in a nondeterministic/deterministic maximally parallel manner, transitions between the system configurations can be obtained. A sequence of transitions is a computation of how the system is evolving. Various ways of controlling the transfer of objects from one membrane to another and applying the rules, as well as possibilities to dissolve, divide or create membranes have been studied. Membrane systems have a great potential for implementing massively concurrent systems in an efficient way that would allow us to solve currently intractable problems once future biotechnology gives way to a practical bio-realization. In this paper we survey some interesting and fundamental complexity issues such as universality vs. nonuniversality, determinism vs. nondeterminism, membrane and alphabet size hierarchies, characterizations of context-sensitive languages and other language classes and various notions of parallelism
Toward Cultural Oncology: The Evolutionary Information Dynamics of Cancer
'Racial' disparities among cancers, particularly of the breast and prostate, are something of a mystery. For the US, in the face of slavery and its sequelae, centuries of interbreeding have greatly leavened genetic differences between 'Blacks' and 'whites', but marked contrasts in disease prevalence and progression persist. 'Adjustment' for socioeconomic status and lifestyle, while statistically accounting for much of the variance in breast cancer, only begs the question of ultimate causality. Here we propose a more basic biological explanation that extends the theory of immune cognition to include elaborate tumor control mechanisms constituting the principal selection pressure acting on pathologically mutating cell clones. The interplay between them occurs in the context of an embedding, highly structured, system of culturally specific psychosocial stress which we find is able to literally write an image of itself onto disease progression. The dynamics are analogous to punctuated equilibrium in simple evolutionary proces
A Bootstrap Theory: the SEMAT Kernel Itself as Runnable Software
The SEMAT kernel is a thoroughly thought generic framework for Software
Engineering system development in practice. But one should be able to test its
characteristics by means of a no less generic theory matching the SEMAT kernel.
This paper claims that such a matching theory is attainable and describes its
main principles. The conceptual starting point is the robustness of the Kernel
alphas to variations in the nature of the software system, viz. to software
automation, distribution and self-evolution. From these and from observed
Kernel properties follows the proposed bootstrap principle: a software system
theory should itself be a runnable software. Thus, the kernel alphas can be
viewed as a top-level ontology, indeed the Essence of Software Engineering.
Among the interesting consequences of this bootstrap theory, the observable
system characteristics can now be formally tested. For instance, one can check
the system completeness, viz. that software system modules fulfill each one of
the system requirements.Comment: 8 pages; 2 figures; Preprint of paper accepted for GTSE'2014
Workshop, within ICSE'2014 Conferenc
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