## Electronic Journal of Probability

### Transportation–cost inequalities for diffusions driven by Gaussian processes

Sebastian Riedel

#### Abstract

We prove transportation–cost inequalities for the law of SDE solutions driven by general Gaussian processes. Examples include the fractional Brownian motion, but also more general processes like bifractional Brownian motion. In case of multiplicative noise, our main tool is Lyons’ rough paths theory. We also give a new proof of Talagrand’s transportation–cost inequality on Gaussian Fréchet spaces. We finally show that establishing transportation–cost inequalities implies that there is an easy criterion for proving Gaussian tail estimates for functions defined on that space. This result can be seen as a further generalization of the “generalized Fernique theorem” on Gaussian spaces [FH14, Theorem 11.7] used in rough paths theory.

#### Article information

Source
Electron. J. Probab., Volume 22 (2017), paper no. 24, 26 pp.

Dates
Accepted: 21 February 2017
First available in Project Euclid: 4 March 2017

https://projecteuclid.org/euclid.ejp/1488596710

Digital Object Identifier
doi:10.1214/17-EJP40

Mathematical Reviews number (MathSciNet)
MR3622894

Zentralblatt MATH identifier
1373.60072

#### Citation

Riedel, Sebastian. Transportation–cost inequalities for diffusions driven by Gaussian processes. Electron. J. Probab. 22 (2017), paper no. 24, 26 pp. doi:10.1214/17-EJP40. https://projecteuclid.org/euclid.ejp/1488596710

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