scholarly journals Microscopically Reversible Pathways with Memory

Mathematics ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 127
Author(s):  
Jose Ricardo Arias-Gonzalez
Keyword(s):  
Single Molecule ◽  
Stochastic System ◽  
Physical System ◽  
Thermodynamic System ◽  
Environmental Constraints ◽  
Small System ◽  
Independent Events ◽  
Equilibrium Processes ◽  
History Of ◽  
With Memory

Statistical mechanics is a physics theory that deals with ensembles of microstates of a system compatible with environmental constraints and that on average define a thermodynamic state. The evolution of a small system is normally subjected to changing constraints, as set by a protocol, and involves a stochastic dependence on previous events. Here, we generalize the dynamic trajectories described by a realization of a physical system without dissipation to include those in which the history of previous events is necessary to understand its future. This framework is then used to characterize the processes experienced by the stochastic system, as derived from ensemble averages over the available pathways. We find that the pathways that the system traces in the presence of a protocol entail different statistics from those in its absence and prove that both types of pathways are equivalent in the limit of independent events. Such equivalence implies that a thermodynamic system cannot evolve away from equilibrium in the absence of memory. These results are useful to interpret single-molecule experiments in biophysics and other fields in nanoscience, as well as an adequate platform to describe non-equilibrium processes.

scholarly journals Cognition is not exceptional

2018 ◽  
Vol 26 (1) ◽  
pp. 33-36 ◽  
Author(s):  
Simon McGregor
Keyword(s):  
Cognitive Science ◽  
Physical System ◽  
Special Group ◽  
Opinion Piece ◽  
History Of ◽  
Polar Opposite ◽  
The Universe

Humans have a long history of insisting that they are members of a special group with some uniquely privileged characteristic and eventually being proved wrong. This has played out in cognitive science as in disciplines such as history or ethology. In this opinion piece, I spell out a position, here termed ‘radical pancognitivism’, that constitutes the polar opposite of cognitive exceptionalism, in that it attributes cognition to literally every physical system in the universe. My aim is not to persuade the reader that this view is correct, but rather to air it seriously for the benefit of discussion.

Virginia Woolf in Greece: “Curious contrasts!”: Hellenism and Englishness

2018 ◽  
Author(s):  
Jeanette McVicker
Keyword(s):  
National Identity ◽  
Virginia Woolf ◽  
Common People ◽  
Personal Loss ◽  
Personal Experiences ◽  
Lytton Strachey ◽  
History Of ◽  
Changing Times ◽  
With Memory

A young Virginia Stephen describes the rustic beauty of Salisbury plain and its surroundings (including Stonehenge) in an early voicing of Englishness in the 1903 journal. Three years later, Virginia visits Greece and Turkey, where she begins to contrast that developing sense of Englishness with other nationalisms (German, Greek and Turkish), both resisting and appropriating the language of the tourist. In addition to helping her formulate a sense of national identity, as a woman and a writer, these trips share another aspect: they are suffused by personal experiences of loss (Leslie Stephen’s declining health and death, and Thoby’s sudden death from typhoid). A similar weaving of personal loss with issues of national identity can be detected in her diary during her second journey to Greece in the company of Leonard, Roger and Margery Fry in 1932, prompted by the deaths of Lytton Strachey and Dora Carrington, and her return to the English countryside. This paper explores the relation that these specific journeys, 30 years apart, have to Woolf’s developing sense of tradition, history, and western civilization, and her own place as a writer. The interweaving of the rustic – peasants, common people, villages and natural places – with the history of ideas allows Woolf to reimagine the legacy of heritage for her dramatically changing times. That heritage, intimately bound up with death – whether neutralized as an ancestral past or bearing the sting of the lived present – shapes the way Woolf engages with memory, beauty, and the contemporary role of the English writer.

Attention Deficit

2019 ◽  
pp. 54-70
Author(s):  
David L. Brody
Keyword(s):  
Attention Deficit ◽  
Attention Deficit Disorder ◽  
Criminal Behavior ◽  
Cognitive Rehabilitation ◽  
Speech Therapy ◽  
Cardiovascular Exercise ◽  
History Of ◽  
Attention Performance ◽  
Mixed Salts ◽  
With Memory

Many concussion patients who complain about problems with memory actually have an attention deficit. General measures: treat insomnia, stop alcohol, treat migraine with cogniphobia, prescribe moderate cardiovascular exercise, and refer for cognitive rehabilitation (occupational and speech therapy). Consider treatment with a stimulant such as methylphenidate (Ritalin) or amphetamine mixed salts (Adderall) if appropriate with careful monitoring for side effects. Contraindications include uncontrolled seizures, dangerous anxiety, active cardiovascular or cerebrovascular disease, active psychosis, drug abuse, irresponsible criminal behavior, dangerously underweight, and uncontrolled headaches. Recommend use 6 days per week 51 weeks per year to reduce tolerance. Additional benefit in some patients from donepezil (Aricept), rivastigmine (Exelon), and regulated caffeine use. Approach options: “aggressive” involving treatment with stimulants primarily based on history, “moderate” involving treatment with stimulants only in patients with attention performance impairments documented with neuropsychological evaluation, and “conservative” not including stimulants unless there is a well-documented preinjury history of attention deficit disorder.

Attention Deficit

2014 ◽  
pp. 35-44
Author(s):  
David L Brody
Keyword(s):  
Attention Deficit ◽  
Attention Deficit Disorder ◽  
Criminal Behavior ◽  
Cognitive Rehabilitation ◽  
Speech Therapy ◽  
Cardiovascular Exercise ◽  
History Of ◽  
Attention Performance ◽  
Mixed Salts ◽  
With Memory

Many concussion patients who complain about problems with memory actually have an attention deficit. General measures: treat insomnia, stop alcohol, prescribe moderate cardiovascular exercise, and refer for cognitive rehabilitation (occupational and speech therapy). Consider treatment with a stimulant such as methylphenidate (Ritalin), amphetamine mixed salts (Adderall), and atomoxetine (Strattera), if appropriate, with careful monitoring for side effects. Contraindications include uncontrolled seizures, dangerous anxiety, active cardiovascular or cerebrovascular disease, active psychosis, drug abuse, irresponsible criminal behavior, dangerously underweight, and uncontrolled headaches. Recommend use is 6 days per week 51 weeks per year to reduce tolerance. Some patients find additional benefit from donepezil, rivastigmine, and regulated caffeine use. Approach options: “aggressive,” involving treatment with stimulants primarily based on history; “moderate,” involving treatment with stimulants only in patients with attention performance impairments documented with neuropsychological evaluation; and “conservative,” not including stimulants unless there is a well-documented history of preinjury attention deficit disorder.

Oral History and Feminist Method

2019 ◽  
pp. 40-61
Author(s):  
Margaretta Jolly
Keyword(s):  
Life Course ◽  
Oral History ◽  
Baby Boomers ◽  
Second Generation ◽  
Ethical Challenges ◽  
History Of ◽  
Post War ◽  
With Memory ◽  
Life Course Analysis ◽  
Second Generation Migrants

The chapter unpacks the book’s method as a history of living activists, set in the context of feminism’s affiliation with oral history and life-course analysis. It discusses the S&A oral history archive on which the book is based, outlining how S&A approached interviewee selection and representation, and acknowledging how such questions continue to divide the movement. Offering an overview of feminist oral history practice, addressing the ethics involved and the interpretative challenges of working with memory, subjectivity and emotion, it shows how the ‘baby boomers’, ‘second generation migrants’ and ‘lesbian-feminists’ who powered the WLM were shaped by the post-war worlds in which they grew up, and talked back to these categories, particularly as they gained control over fertility. The chapter concludes with the story of Sue Lopez, women’s footballer and champion for women’s rights in the sport, demonstrating oral history’s ethical challenges whilst celebrating an inspiring athlete and campaigner. 149 words

scholarly journals Relations entre l’entropie physique, le codage de l’information et l’énergie de simulation

2007 ◽  
Vol 85 (12) ◽  
pp. 1381-1394 ◽  
Author(s):  
M Bigerelle ◽  
A Iost
Keyword(s):  
Free Energy ◽  
Computer Program ◽  
Turing Machine ◽  
Physical System ◽  
Ternary Systems ◽  
Thermodynamic System ◽  
Run Length ◽  
Mixing Entropy ◽  
Binary And Ternary Systems

It is shown that an isomorphism exists between the mixing entropy and the size of a computer program that simulates the physical system. This isomorphism must be constructed with respect to some theorems, and it is shown that the composition of two isomorphisms, one based on a run length encoding and another by encoding sequences in a dictionary allows us to quantify the entropy of binary and ternary systems at the equilibrium. Finally, it is shown that the energy consumed by a physical system encoded by this system and executed on a Turing machine is proportional to the free energy of the thermodynamic system.

Analysis of parasite host-switching: limitations on the use of phylogenies

Parasitology ◽  
1999 ◽  
Vol 119 (S1) ◽  
pp. S111-S123 ◽  
Author(s):  
J. A. Jackson
Keyword(s):  
Host Species ◽  
Host Tree ◽  
Host Switching ◽  
Environmental Constraints ◽  
Important Process ◽  
Potential Host ◽  
Historical Reconstructions ◽  
History Of ◽  
Host Parasite ◽  
Parasite Assemblages

SUMMARYEven the most generalist parasites usually occur in only a subset of potential host species, a tendency which reflects overriding environmental constraints on their distributions in nature. The periodic shifting of these limitations represented by host-switches may have been an important process in the evolution of many host-parasite assemblages. To study such events, however, it must first be established where and when they have occurred. Past host-switches within a group of parasites are usually inferred from a comparison of the parasite phylogeny with that of the hosts. Congruence between the phylogenies is often attributed to a history of association by descent with cospeciation, and incongruence to host-switching or extinction in ‘duplicated’ parasite lineages (which diverged without a corresponding branching of the host tree). The inference of host-switching from incongrucnt patterns is discussed. Difficulties arise because incongruence can frequently be explained by different combinations of biologically distinct events whose relative probabilities are uncertain. Also, the models of host parasite relationships implicit in historical reconstructions may often not allow for plausible sources of incongruence other than host-switching or duplication/extinction, or for the possibility that colonization could, in some circumstances, be disguised by ‘false’ congruence.

scholarly journals Generalized Memory: Fractional Calculus Approach

2018 ◽  
Vol 2 (4) ◽  
pp. 23 ◽  
Author(s):  
Vasily E. Tarasov
Keyword(s):  
Differential Equations ◽  
Fractional Calculus ◽  
Power Law ◽  
Memory Function ◽  
Time Interval ◽  
Infinite Time ◽  
Suggested Approach ◽  
Infinite Time Interval ◽  
History Of ◽  
With Memory

The memory means an existence of output (response, endogenous variable) at the present time that depends on the history of the change of the input (impact, exogenous variable) on a finite (or infinite) time interval. The memory can be described by the function that is called the memory function, which is a kernel of the integro-differential operator. The main purpose of the paper is to answer the question of the possibility of using the fractional calculus, when the memory function does not have a power-law form. Using the generalized Taylor series in the Trujillo-Rivero-Bonilla (TRB) form for the memory function, we represent the integro-differential equations with memory functions by fractional integral and differential equations with derivatives and integrals of non-integer orders. This allows us to describe general economic dynamics with memory by the methods of fractional calculus. We prove that equation of the generalized accelerator with the TRB memory function can be represented by as a composition of actions of the accelerator with simplest power-law memory and the multi-parametric power-law multiplier. As an example of application of the suggested approach, we consider a generalization of the Harrod-Domar growth model with continuous time.

The Individual as System

2019 ◽  
Vol 49 (3) ◽  
pp. 215-234
Author(s):  
Shachar Freddy Kislev ◽  
Keyword(s):  
Systems Theory ◽  
History Of Philosophy ◽  
Small System ◽  
The Social ◽  
History Of ◽  
Concrete Universal ◽  
Psychological Sense ◽  
The Individual

In British Hegelianism we find, forgotten, a weighty theory of individuality. This theory remains one of the most sustained attempts in the history of philosophy to analyze the individual, not in the social or psychological sense, but as a logical-metaphysical category. The Idealist conceptualization of the individual is bound with their unconventional theory of universals, for they argued that any individual is a “concrete universal,” and vice versa. This article reconstructs the British Idealist theory of individuality, highlighting its key insights: (a) the individual is not a simple unit, but a small system with interrelated parts; (b) the individual is not simply given, but is mediated by thought; (c) the individual is the conceptual glue holding the parts together and assigning them their respective places; (d) the conceptualization of the individual lies at the intersection of logic, aesthetics and systems theory.

scholarly journals Memfractance: A Mathematical Paradigm for Circuit Elements with Memory

2014 ◽  
Vol 24 (09) ◽  
pp. 1430023 ◽  
Author(s):  
Mohammed-Salah Abdelouahab ◽  
René Lozi ◽  
Leon Chua
Keyword(s):  
Fractional Calculus ◽  
Nanoscale Device ◽  
Circuit Element ◽  
Ohm’S Law ◽  
History Of ◽  
Memristive Systems ◽  
Ohm's Law ◽  
Inductive Elements ◽  
Passive Circuit ◽  
With Memory

Memristor, the missing fourth passive circuit element predicted forty years ago by Chua was recognized as a nanoscale device in 2008 by researchers of a H. P. Laboratory. Recently the notion of memristive systems was extended to capacitive and inductive elements, namely, memcapacitor and meminductor whose properties depend on the state and history of the system. In this paper, we use fractional calculus to generalize and provide a mathematical paradigm for describing the behavior of such elements with memory. In this framework, we extend Ohm's law to the generalized Ohm's law and prove it.

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