随机偏微分方程
随机偏微分方程(英文:Stochastic partial differential equation,SPDE)为偏微分方程引入了随机项和随机系数,类似于随机微分方程之于常微分方程。随机微分方程在量子场论、统计力学、金融数学中有着广泛的应用。[1][2]
示例
最常见的SPDE之一是随机热传导方程[3] ,形式上可以写作
讨论
一个困难是缺乏正规性。在一个空间维度中,随机热传导方程的解在空间上几乎只有1/2-赫尔德连续,在时间上则只有1/4-赫尔德连续。对于二维及更高维度,解甚至不是函数值,但可以理解为随机分布。
对于线性方程,通常可以通过半群手段找到温和解(mild solution)。[6] 然而,当考虑非线性方程时,问题就开始出现了。例如
其中 是多项式。在这种情况下,我们甚至不知道该如何理解这个方程。这样的方程在多维情形下也不会有数值解,因此也没有点。众所周知,分布空间没有积结构。这是此类理论的核心问题。这就需要某种形式的重整化。
为规避某些特定方程的此类问题,早期的尝试是所谓的“普拉托-德布斯切技巧”(da Prato–Debussche trick),即把此类非线性方程作为线性方程的扰动来研究。[7]然而,这只能在非常受限的环境中使用,因为它既取决于非线性因子,也取决于驱动噪声项的正规性。近年来,这一领域急剧扩大,现在已有大型机制可以保证各种亚临界SPDE的局部存在性。[8]
另见
参考文献
- ^ Prévôt, Claudia; Röckner, Michael. A Concise Course on Stochastic Partial Differential Equations. Lecture Notes in Mathematics. Berlin Heidelberg: Springer-Verlag. 2007 [2023-10-29]. ISBN 978-3-540-70780-6. (原始内容存档于2020-03-29) (英语).
- ^ Krainski, Elias T.; Gómez-Rubio, Virgilio; Bakka, Haakon; Lenzi, Amanda; Castro-Camilo, Daniela; Simpson, Daniel; Lindgren, Finn; Rue, Håvard. Advanced Spatial Modeling with Stochastic Partial Differential Equations Using R and INLA. Boca Raton, FL: Chapman and Hall/CRC Press. 2018 [2023-10-29]. ISBN 978-1-138-36985-6. (原始内容存档于2020-03-29).
- ^ Edwards, S.F.; Wilkinson, D.R. The Surface Statistics of a Granular Aggregate. Proc. R. Soc. Lond. A. 1982-05-08, 381 (1780): 17–31 [2023-10-29]. doi:10.1098/rspa.1982.0056. (原始内容存档于2023-12-29) (英语).
- ^ Dalang, Robert C.; Frangos, N. E. The Stochastic Wave Equation in Two Spatial Dimensions. The Annals of Probability. 1998, 26 (1): 187–212 [2023-10-29]. ISSN 0091-1798. (原始内容存档于2023-05-09).
- ^ Diósi, Lajos; Strunz, Walter T. The non-Markovian stochastic Schrödinger equation for open systems. Physics Letters A. 1997-11-24, 235 (6): 569–573. ISSN 0375-9601. arXiv:quant-ph/9706050 . doi:10.1016/S0375-9601(97)00717-2 (英语).
- ^ Walsh, John B. Carmona, René; Kesten, Harry; Walsh, John B.; Hennequin, P. L. , 编. An introduction to stochastic partial differential equations. École d'Été de Probabilités de Saint Flour XIV - 1984. Lecture Notes in Mathematics (Springer Berlin Heidelberg). 1986, 1180: 265–439. ISBN 978-3-540-39781-6. doi:10.1007/bfb0074920 (英语).
- ^ Da Prato, Giuseppe; Debussche, Arnaud. Strong Solutions to the Stochastic Quantization Equations. Annals of Probability. 2003, 31 (4): 1900–1916. JSTOR 3481533.
- ^ Corwin, Ivan; Shen, Hao. Some recent progress in singular stochastic partial differential equations. Bull. Amer. Math. Soc. 2020, 57 (3): 409–454. doi:10.1090/bull/1670 .
阅读更多
- Bain, A.; Crisan, D. Fundamentals of Stochastic Filtering. Stochastic Modelling and Applied Probability 60. New York: Springer. 2009. ISBN 978-0387768953.
- Holden, H.; Øksendal, B.; Ubøe, J.; Zhang, T. Stochastic Partial Differential Equations: A Modeling, White Noise Functional Approach. Universitext 2nd. New York: Springer. 2010. ISBN 978-0-387-89487-4. doi:10.1007/978-0-387-89488-1.
- Lindgren, F.; Rue, H.; Lindström, J. An Explicit Link between Gaussian Fields and Gaussian Markov Random Fields: The Stochastic Partial Differential Equation Approach. Journal of the Royal Statistical Society Series B: Statistical Methodology. 2011, 73 (4): 423–498 [2023-10-29]. ISSN 1369-7412. doi:10.1111/j.1467-9868.2011.00777.x. hdl:20.500.11820/1084d335-e5b4-4867-9245-ec9c4f6f4645 . (原始内容存档于2024-04-27).
- Xiu, D. Numerical Methods for Stochastic Computations: A Spectral Method Approach. Princeton University Press. 2010. ISBN 978-0-691-14212-8.
外部链接
- A Minicourse on Stochastic Partial Differential Equations (PDF). 2006.
- Hairer, Martin. An Introduction to Stochastic PDEs. 2009. arXiv:0907.4178 [math.PR].