We know that stress-factors, e.g. X-rays, have an effect on cells that is more lethal in rapid ex... more We know that stress-factors, e.g. X-rays, have an effect on cells that is more lethal in rapid exponential growth than in stationary phase. It is this effect which makes radiotherapy effective in cancer treatment. This stress effect can be explained in two ways: (a) more vulnerability in the growth phase, (b) improved protection capacity and repair mechanisms in the stationary phase. Although the two explanations do not exclude each other, they are very different in the sense that (a) is a general mechanism whereas (b) is strain and stress-factor dependent. In this paper we explore major facets of (a). Firstly, we emphasize that (a) can account for known experimental stress-factor evidence. Secondly, we observe that (a) rightly predicts that slow exponential growth (meaning with a doubling time of several hours) results in a lower death rate than fast exponential growth (doubling time of a fraction of one hour), an effect that cannot be explained in the (b) framework because both or...
We consider a generalization of the Heath Jarrow Morton model for the term structure of interest ... more We consider a generalization of the Heath Jarrow Morton model for the term structure of interest rates where the forward rate is driven by Paretian fluctuations. We derive a generalization of Itô's lemma for the calculation of a differential of a Paretian stochastic variable and use it to derive a Stochastic Differential Equation for the discounted bond price. We show that it is not possible to choose the parameters of the model to ensure absence of drift of the discounted bond price. Then we consider a Continuous Time Random Walk with jumps driven by Paretian random variables and we derive the large time scaling limit of the jump probability distribution function (pdf). We show that under certain conditions defined in text the large time scaling limit of the jump pdf in the Fourier domain is õm̃ẽg̃ã_t(k,t) ∼-K/((k t))^2 and is different from the case of a random walk with Gaussian fluctuations. We also derive the master equation for the jump pdf and discuss the relation of the ...
Investigating the ``physics'' of food crises consists in identifying features which are c... more Investigating the ``physics'' of food crises consists in identifying features which are common to all large-scale food crises. One element which stands out is the fact that during a food crisis there is not only a surge in deaths but also a correlative temporary decline in conceptions and subsequent births. As a matter of fact, birth reduction may even start several months before the death surge and can therefore serve as an early warning signal of an impending crisis. This scenario is studied in three cases of large-scale food crises. Finland (1868), India (1867--1907), China (1960--1961). It turns out that between the regional amplitudes of death spikes and birth troughs there is a power law relationship. This confirms what was already observed for the epidemic of 1918 in the United States (Richmond et al. 2018b). In a second part of the paper we explain how this relationship can be used for the investigation of mass-mortality episodes in cases where direct death data are ...
Pricing of options on stocks that are driven by multi-dimensional coupled price-temporal infinite... more Pricing of options on stocks that are driven by multi-dimensional coupled price-temporal infinitely divisible fluctuations. We model the price of a stock via a Langévin equation with multi-dimensional fluctuations coupled both in the price in time. We generalise previous models in that we assume that the fluctuations conditioned on the time step are assumed to be compound Poisson processes with operator stable jump intensities. We derive exact relations for Fourier transforms of the jump intensity in case of different scaling indices E of the process. We express the Fourier transform of the joint probability density of the process to attain given values at several different times and to attain a given maximal value in a given time period through Fourier transforms of the jump intensity. Then we consider a portfolio composed of stocks and of options on stocks and we derive the Fourier transform of a random variable Dt (deviation of the portfolio) that is defined as a small temporal c...
This paper is not (or at least not only) about human infant mortality. In line with reliability t... more This paper is not (or at least not only) about human infant mortality. In line with reliability theory, "infant" will refer here to the time interval following birth during which the mortality (or failure) rate decreases. This definition provides a systems science perspective in which birth constitutes a sudden transition which falls within the field of application of the "Transient Shock" (TS) conjecture put forward in Richmond et al. (2016c). This conjecture provides predictions about the timing and shape of the death rate peak. (i) It says that there will be a death rate spike whenever external conditions change abruptly and drastically. (ii) It predicts that after a steep rising there will be a much longer hyperbolic relaxation process. These predictions can be tested by considering living organisms for which birth is a multi-step process. Thus, for fish there are three states: egg, yolk-sac phase, young adult. The TS conjecture predicts a mortality spike at ...
The influence of per capita income on life expectancy is well documented, mostly through studies ... more The influence of per capita income on life expectancy is well documented, mostly through studies of multinational samples. However, one expects fairly weak correlations at both ends of the life span, that is to say in early infancy and in age groups of elderly from 85 to 100 years. The reason is that at both ends mortality is largely controled by biological factors rather than by socio-economic conditions. In order to test this conjecture, we explore the influence of income on age groups, separately in France, the United States and South Korea. More precisely in each country we compare income and mortality data in as many regional subunits as possible. One noteworthy constatation is that, contrary to a common view, personal income is only weakly correlated with infant mortality (i.e. mortality under the age of one year). More broadly, we propose as a conjecture that the common pattern revealed by the analysis of the three countries is also valid in other developed countries. 1: Scho...
In 2015 in the United States 612,000 persons died from cancer whereas only 470 died from tubercul... more In 2015 in the United States 612,000 persons died from cancer whereas only 470 died from tuberculosis (TB), a disease which was the main cause of death around 1900. How can one explain such a key discrepancy in treatment progress? A statistical comparison between TB and cancer will give some clues. However, TB and cancer also share several important features. Both TB and cancer can affect several organs, e.g. lungs, brain, bones, intestines, skin. What in cancer is called malignant neoplasm (tumor) is called granuloma in TB. By isolating malignant cells (versus bacteria) from the rest of the body, such clusters protect the host's organism but at the same time they are "secure beachheads" from where malignant cells (versus infected macrophages) can wander off to new locations. Thus, metastatic tumors have a TB parallel in the form of secondary granulomas. In order to investigate more closely this parallel we use the age-specific response of organs. Called spectrometric ...
The properties of a conduction electron in a ferromagnetic crystal (magnetic polaron) have been i... more The properties of a conduction electron in a ferromagnetic crystal (magnetic polaron) have been investigated. The magnetic spins are treated within the idealized boson representation. At absolute zero a large number of terms in the perturbation expansion are zero and the remainder can be summed exactly. For strong coupling it is demonstrated that, for certain total spin states, slight narrowing of the conduction electron bandwidth can occur. This narrowing depends on the magnitude of the atomic spin in the form of a factor 2s/2s+1.
Physica A: Statistical Mechanics and its Applications, 2016
This paper is about infant mortality. In line with reliability theory, “infant” refers to the tim... more This paper is about infant mortality. In line with reliability theory, “infant” refers to the time interval following birth during which the mortality (or failure) rate decreases. This definition provides a systems science perspective in which birth constitutes a sudden transition falling within the field of application of the Transient Shock (TS) conjecture put forward in Richmond and Roehner (2016c). This conjecture provides predictions about the timing and shape of the death rate peak. It says that there will be a death rate spike whenever external conditions change abruptly and drastically and also predicts that after a steep rise there will be a much longer hyperbolic relaxation process.
This paper examines the applicability of Random Matrix Theory to portfolio management in finance.... more This paper examines the applicability of Random Matrix Theory to portfolio management in finance. Starting from a group of normally distributed stochastic processes with given correlations we devise an algorithm for removing noise from the estimator of correlations constructed from measured time series. We then apply this algorithm to historical time series for the Standard and Poor's 500 index. We discuss to what extent the noise can be removed and whether the resulting underlying correlations are sufficiently accurate for portfolio management purposes.
We model the price of a stock via a Lang\'{e}vin equation with multi-dimensional fluctuations... more We model the price of a stock via a Lang\'{e}vin equation with multi-dimensional fluctuations coupled in the price and in time. We generalize previous models in that we assume that the fluctuations conditioned on the time step are compound Poisson processes with operator stable jump intensities. We derive exact relations for Fourier transforms of the jump intensity in case of different scaling indices $\underline{\underline{E}}$ of the process. We express the Fourier transform of the joint probability density of the process to attain given values at several different times and to attain a given maximal value in a given time period through Fourier transforms of the jump intensity. Then we consider a portfolio composed of stocks and of options on stocks and we derive the Fourier transform of a random variable $\mathfrak{D}_t$ (deviation of the portfolio) that is defined as a small temporal change of the portfolio diminished by the the compound interest earned. We show that if the ...
We know that stress-factors, e.g. X-rays, have an effect on cells that is more lethal in rapid ex... more We know that stress-factors, e.g. X-rays, have an effect on cells that is more lethal in rapid exponential growth than in stationary phase. It is this effect which makes radiotherapy effective in cancer treatment. This stress effect can be explained in two ways: (a) more vulnerability in the growth phase, (b) improved protection capacity and repair mechanisms in the stationary phase. Although the two explanations do not exclude each other, they are very different in the sense that (a) is a general mechanism whereas (b) is strain and stress-factor dependent. In this paper we explore major facets of (a). Firstly, we emphasize that (a) can account for known experimental stress-factor evidence. Secondly, we observe that (a) rightly predicts that slow exponential growth (meaning with a doubling time of several hours) results in a lower death rate than fast exponential growth (doubling time of a fraction of one hour), an effect that cannot be explained in the (b) framework because both or...
We consider a generalization of the Heath Jarrow Morton model for the term structure of interest ... more We consider a generalization of the Heath Jarrow Morton model for the term structure of interest rates where the forward rate is driven by Paretian fluctuations. We derive a generalization of Itô's lemma for the calculation of a differential of a Paretian stochastic variable and use it to derive a Stochastic Differential Equation for the discounted bond price. We show that it is not possible to choose the parameters of the model to ensure absence of drift of the discounted bond price. Then we consider a Continuous Time Random Walk with jumps driven by Paretian random variables and we derive the large time scaling limit of the jump probability distribution function (pdf). We show that under certain conditions defined in text the large time scaling limit of the jump pdf in the Fourier domain is õm̃ẽg̃ã_t(k,t) ∼-K/((k t))^2 and is different from the case of a random walk with Gaussian fluctuations. We also derive the master equation for the jump pdf and discuss the relation of the ...
Investigating the ``physics'' of food crises consists in identifying features which are c... more Investigating the ``physics'' of food crises consists in identifying features which are common to all large-scale food crises. One element which stands out is the fact that during a food crisis there is not only a surge in deaths but also a correlative temporary decline in conceptions and subsequent births. As a matter of fact, birth reduction may even start several months before the death surge and can therefore serve as an early warning signal of an impending crisis. This scenario is studied in three cases of large-scale food crises. Finland (1868), India (1867--1907), China (1960--1961). It turns out that between the regional amplitudes of death spikes and birth troughs there is a power law relationship. This confirms what was already observed for the epidemic of 1918 in the United States (Richmond et al. 2018b). In a second part of the paper we explain how this relationship can be used for the investigation of mass-mortality episodes in cases where direct death data are ...
Pricing of options on stocks that are driven by multi-dimensional coupled price-temporal infinite... more Pricing of options on stocks that are driven by multi-dimensional coupled price-temporal infinitely divisible fluctuations. We model the price of a stock via a Langévin equation with multi-dimensional fluctuations coupled both in the price in time. We generalise previous models in that we assume that the fluctuations conditioned on the time step are assumed to be compound Poisson processes with operator stable jump intensities. We derive exact relations for Fourier transforms of the jump intensity in case of different scaling indices E of the process. We express the Fourier transform of the joint probability density of the process to attain given values at several different times and to attain a given maximal value in a given time period through Fourier transforms of the jump intensity. Then we consider a portfolio composed of stocks and of options on stocks and we derive the Fourier transform of a random variable Dt (deviation of the portfolio) that is defined as a small temporal c...
This paper is not (or at least not only) about human infant mortality. In line with reliability t... more This paper is not (or at least not only) about human infant mortality. In line with reliability theory, "infant" will refer here to the time interval following birth during which the mortality (or failure) rate decreases. This definition provides a systems science perspective in which birth constitutes a sudden transition which falls within the field of application of the "Transient Shock" (TS) conjecture put forward in Richmond et al. (2016c). This conjecture provides predictions about the timing and shape of the death rate peak. (i) It says that there will be a death rate spike whenever external conditions change abruptly and drastically. (ii) It predicts that after a steep rising there will be a much longer hyperbolic relaxation process. These predictions can be tested by considering living organisms for which birth is a multi-step process. Thus, for fish there are three states: egg, yolk-sac phase, young adult. The TS conjecture predicts a mortality spike at ...
The influence of per capita income on life expectancy is well documented, mostly through studies ... more The influence of per capita income on life expectancy is well documented, mostly through studies of multinational samples. However, one expects fairly weak correlations at both ends of the life span, that is to say in early infancy and in age groups of elderly from 85 to 100 years. The reason is that at both ends mortality is largely controled by biological factors rather than by socio-economic conditions. In order to test this conjecture, we explore the influence of income on age groups, separately in France, the United States and South Korea. More precisely in each country we compare income and mortality data in as many regional subunits as possible. One noteworthy constatation is that, contrary to a common view, personal income is only weakly correlated with infant mortality (i.e. mortality under the age of one year). More broadly, we propose as a conjecture that the common pattern revealed by the analysis of the three countries is also valid in other developed countries. 1: Scho...
In 2015 in the United States 612,000 persons died from cancer whereas only 470 died from tubercul... more In 2015 in the United States 612,000 persons died from cancer whereas only 470 died from tuberculosis (TB), a disease which was the main cause of death around 1900. How can one explain such a key discrepancy in treatment progress? A statistical comparison between TB and cancer will give some clues. However, TB and cancer also share several important features. Both TB and cancer can affect several organs, e.g. lungs, brain, bones, intestines, skin. What in cancer is called malignant neoplasm (tumor) is called granuloma in TB. By isolating malignant cells (versus bacteria) from the rest of the body, such clusters protect the host's organism but at the same time they are "secure beachheads" from where malignant cells (versus infected macrophages) can wander off to new locations. Thus, metastatic tumors have a TB parallel in the form of secondary granulomas. In order to investigate more closely this parallel we use the age-specific response of organs. Called spectrometric ...
The properties of a conduction electron in a ferromagnetic crystal (magnetic polaron) have been i... more The properties of a conduction electron in a ferromagnetic crystal (magnetic polaron) have been investigated. The magnetic spins are treated within the idealized boson representation. At absolute zero a large number of terms in the perturbation expansion are zero and the remainder can be summed exactly. For strong coupling it is demonstrated that, for certain total spin states, slight narrowing of the conduction electron bandwidth can occur. This narrowing depends on the magnitude of the atomic spin in the form of a factor 2s/2s+1.
Physica A: Statistical Mechanics and its Applications, 2016
This paper is about infant mortality. In line with reliability theory, “infant” refers to the tim... more This paper is about infant mortality. In line with reliability theory, “infant” refers to the time interval following birth during which the mortality (or failure) rate decreases. This definition provides a systems science perspective in which birth constitutes a sudden transition falling within the field of application of the Transient Shock (TS) conjecture put forward in Richmond and Roehner (2016c). This conjecture provides predictions about the timing and shape of the death rate peak. It says that there will be a death rate spike whenever external conditions change abruptly and drastically and also predicts that after a steep rise there will be a much longer hyperbolic relaxation process.
This paper examines the applicability of Random Matrix Theory to portfolio management in finance.... more This paper examines the applicability of Random Matrix Theory to portfolio management in finance. Starting from a group of normally distributed stochastic processes with given correlations we devise an algorithm for removing noise from the estimator of correlations constructed from measured time series. We then apply this algorithm to historical time series for the Standard and Poor's 500 index. We discuss to what extent the noise can be removed and whether the resulting underlying correlations are sufficiently accurate for portfolio management purposes.
We model the price of a stock via a Lang\'{e}vin equation with multi-dimensional fluctuations... more We model the price of a stock via a Lang\'{e}vin equation with multi-dimensional fluctuations coupled in the price and in time. We generalize previous models in that we assume that the fluctuations conditioned on the time step are compound Poisson processes with operator stable jump intensities. We derive exact relations for Fourier transforms of the jump intensity in case of different scaling indices $\underline{\underline{E}}$ of the process. We express the Fourier transform of the joint probability density of the process to attain given values at several different times and to attain a given maximal value in a given time period through Fourier transforms of the jump intensity. Then we consider a portfolio composed of stocks and of options on stocks and we derive the Fourier transform of a random variable $\mathfrak{D}_t$ (deviation of the portfolio) that is defined as a small temporal change of the portfolio diminished by the the compound interest earned. We show that if the ...
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