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11.
We provide a representation for the nonmyopic optimal portfolio of an agent consuming only at the terminal horizon when the single state variable follows a general diffusion process and the market consists of one risky asset and a risk-free asset. The key term of our representation is a new object that we call the “rate of macroeconomic fluctuation” whose properties are fundamental for the portfolio dynamics. We show that, under natural cyclicality conditions, (i) the agent’s hedging demand is positive (negative) when the product of his prudence and risk tolerance is below (above) two and (ii) the portfolio weights decrease in risk aversion. We apply our results to study a general continuous-time capital asset pricing model and show that under the same cyclicality conditions, the market price of risk is countercyclical and the price of the risky asset exhibits excess volatility. 相似文献
12.
Semyon Yakubovich 《Comptes Rendus Mathematique》2011,349(11-12):633-636
By using structural and asymptotic properties of the Kontorovich–Lebedev transform associated with Minkowski?s question mark function, we give an affirmative answer to the question posed by R. Salem (Trans. Amer. Math. Soc. 53 (3) (1943) 439) whether its Fourier–Stieltjes transform vanishes at infinity. 相似文献
13.
In this paper we study a class of integral transformations with kernels consisting of Lommel's functions of a certain index.
Boundedness properties, Parseval type formula, inversion theorem are proved in Lebesgue spaces of integrable functions.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
14.
15.
Richard Bellman Joseph Bentsman Semyon M. Meerkov 《Journal of Mathematical Analysis and Applications》1983,91(1):152-191
A nonlinear system with S-shape steady state characteristic is referred to as a system with Arrhenius dynamics. The negative slope part of the S-shape curve represents a set of unstable steady states. Using two examples of Arrhenius systems (catalytic reactor and continuous stirred tank reactor), it is shown that introduction of sufficiently fast oscillations in the parameters of the system generates a new Arrhenius system, the steady state characteristic of which has a smaller negative slope part. Results of analytical investigation as well as numerical simulation are presented. It is shown that vibrational stabilization of Arrhenius systems gives an increase in productivity of the plants. 相似文献
16.
A quaternionic version of the Calabi problem on the Monge-Ampère equation is introduced, namely a quaternionic Monge-Ampère
equation on a compact hypercomplex manifold with an HKT-metric. The equation is non-linear elliptic of second order. For a
hypercomplex manifold with holonomy in SL(n,ℍ), uniqueness (up to a constant) of a solution is proven, aas well as the zero order a priori estimate. The existence of
a solution is conjectured, similar to the Calabi-Yau theorem. We reformulate this quaternionic equation as a special case
of the complex Hessian equation, making sense on any complex manifold. 相似文献
17.
Fluorescence experiments on (1-butyl-4-(1H-inden-1-ylidene)-1,4-dihydropyridine (BIDP) are reported in liquid and glassy solutions. The data indicate a fast decay in the fluid nonpolar, nonprotic solutions (decay times approximately 10(-12) s) and rapid but considerably slower decay in polar ones. In frozen solutions (polar and nonpolar), the fluorescence quantum yield is much higher (near 0.5 and around 0.1 in polar and nonpolar glasses, respectively). The rapid nonradiative transitions in fluid solutions are assigned to internal conversion in both solvent classes, as intersystem crossing is much slower and no net reaction is observed. These results are in agreement with predictions made for the closely related (in terms of electronic structure) but simpler molecule cyclopentadienyl-1,4-dihydropyridine (CPDHP) for which an S1/S0 conical intersection was recently proposed [Int. J. Quant. Chem. 2005, 102, 961]. The crossing of the two lowest singlet states is calculated to vanish in polar solvents such as methyl cyanide, leading to longer lifetime of S1 of CPDHP. As BIDP has a very similar electronic structure, the model predicts a corresponding change in this larger molecule. The strong fluorescence observed in the glassy environments is rationalized by the hindering of the internal torsion required to reach the geometry of the conical intersection. 相似文献
18.
Tatiana A. Vovk Semyon S. Rudyi Andrei V. Ivanov Evgeniy Y. Perlin Yuri V. Rozhdestvensky 《Physics letters. A》2019,383(9):923-928
One of the most interesting problems of modern physics is the realization of nanoparticles in macroscopic quantum states, in which they behave as a quantum objects. These states can only be implemented at ultra-low translational temperatures that have not been achieved so far. Here we develop a novel method for optical cooling of CaF2:Yb3+ nanocrystals, which is based on the coherent population transfer induced in the impurity ions by ultraviolet Raman pulses. A doped nanocrystal localized in a radio-frequency trap is cooled due to the photon recoil from the pulses of varied intensity. The proposed method allows to obtain nanocrystals with translational temperatures of the order of 10?9 K, which indicates that the nanocrystal approaches a macroscopic quantum state. 相似文献
19.
Semyon Rafalson 《Journal of Approximation Theory》2001,110(2):489
In this paper we find an extremal relation of the theory of approximation of functions on a finite interval by algebraic polynomials. In the Legendre case we find some estimations and representation in the form of a series of the constant from the extremal relation. 相似文献
20.
Semyon Alesker 《Bulletin des Sciences Mathématiques》2003,127(1):1-35
We remind known and establish new properties of the Dieudonné and Moore determinants of quaternionic matrices. Using these linear algebraic results we develop a basic theory of plurisubharmonic functions of quaternionic variables. 相似文献