This paper considers two types of boundary control problems for linear transport equations. The first one shows that transport solutions on a subdomain of a domain $ X $ can be controlled exactly from incoming boundary conditions for $ X $ under appropriate convexity assumptions. This is in contrast with the only approximate control one typically obtains for elliptic equations by an application of a unique continuation property, a property which we prove does not hold for transport equations. We also consider the control of an outgoing solution from incoming conditions, a transport notion similar to the Dirichlet-to-Neumann map for elliptic equations. We show that for well-chosen coefficients in the transport equation, this control may not be possible. In such situations and by (Fredholm) duality, we obtain the existence of non-trivial incoming conditions that are compatible with vanishing outgoing conditions.
| Citation: |
| [1] |
S. Acosta, Time reversal for radiative transport with applications to inverse and control problems, Inverse Problems, 29 (2013), 085014, 19pp.
doi: 10.1088/0266-5611/29/8/085014.
|
| [2] |
J. H. Albert, Genericity of simple eigenvalues for elliptic PDE's, Proc. Amer. Math. Soc., 48 (1975), 413-418.
doi: 10.2307/2040275.
|
| [3] |
G. S. Alberti and Y. Capdeboscq, Lectures on Elliptic Methods for Hybrid Inverse Problems, Société Mathématique de France, 2018.
|
| [4] |
G. Bal, Inverse transport theory and applications, Inverse Problems, 25 (2009), 053001, 48pp.
doi: 10.1088/0266-5611/25/5/053001.
|
| [5] |
G. Bal, Hybrid inverse problems and internal functionals, in Inside Out II, MSRI Publications, 60 (2013), 325–368.
|
| [6] |
G. Bal, F. J. Chung and J. C. Schotland, Ultrasound modulated bioluminescence tomography and controllability of the radiative transport equation, SIAM Journal on Mathematical Analysis, 48 (2016), 1332-1347.
doi: 10.1137/15M1026262.
|
| [7] |
G. Bal and A. Jollivet, Generalized stability estimates in inverse transport theory, Inverse Problems and Imaging, 12 (2018), 59-90.
doi: 10.3934/ipi.2018003.
|
| [8] |
G. Bal, F. Monard and G. Uhlmann, Reconstruction of a fully anisotropic elasticity tensor from knowledge of displacement fields, SIAM Journal on Applied Mathematics, 75 (2015), 2214-2231.
doi: 10.1137/151005269.
|
| [9] |
G. Bal and G. Uhlmann, Reconstruction of coefficients in scalar second-order elliptic equations from knowledge of their solutions, Commun. Pure Appl. Math., 66 (2013), 1629-1652.
doi: 10.1002/cpa.21453.
|
| [10] |
F. A. Berezin and M. A. Shubin, The Schrödinger Equation, Springer, 1991.
doi: 10.1007/978-94-011-3154-4.
|
| [11] |
M. Cessenat, Théorèmes de trace pour des espaces de fonctions de la neutronique, C. R. Acad. Sci. Paris Sér. I Math., 300 (1985), 89-92.
|
| [12] |
R. Dautray and J.-L. Lions, Mathematical Analysis and Numerical Methods for Science and Technology, Springer-Verlag, Berlin, 1992.
|
| [13] |
H. Egger and M. Schlottbom, An Lp theory for stationary radiative transfer, Appl. Anal., 93 (2014), 1283-1296.
doi: 10.1080/00036811.2013.826798.
|
| [14] |
G. Eskin, Lectures on Linear Partial Differential Equations, Graduate Studies in Mathematics, 123. American Mathematical Society, Providence, RI, 2011.
doi: 10.1090/gsm/123.
|
| [15] |
F. Golse and L. Saint-Raymond, Velocity averaging in $L^1$ for the transport equation, C. R. Math. Acad. Sci. Paris, 334 (2002), 557-562.
doi: 10.1016/S1631-073X(02)02302-6.
|
| [16] |
M. V. Klibanov and M. Yamamoto, Exact controllability for the time dependent transport equation, SIAM J. Control Optim., 46 (2007), 2071-2195.
doi: 10.1137/060652804.
|
| [17] |
E. W. Larsen and J. B. Keller, Asymptotic solution of neutron transport problems for small mean free paths, J. Math. Phys., 15 (1974), 75-81.
doi: 10.1063/1.1666510.
|
| [18] |
P. D. Lax, A stability theorem for solutions of abstract differential equations, and its application to the study of the local behavior of solutions of elliptic equations, Comm. Pure Appl. Math., 9 (1956), 747-766.
doi: 10.1002/cpa.3160090407.
|
| [19] |
W. Magnus, F. Oberhettinger, R. P. Soni, Formulas and Theorems for the Special Functions of Mathematical Physics, Third enlarged edition. Die Grundlehren der mathematischen Wissenschaften, Band 52 Springer-Verlag New York, Inc., New York, 1966.
|
| [20] |
M. Mokhtar-Kharroubi, Mathematical Topics in Neutron Transport Theory. New Aspects, With a chapter by M. Choulli and P. Stefanov, Series on Advances in Mathematics for Applied Sciences, 46. World Scientific Publishing Co., Inc., River Edge, NJ, 1997.
doi: 10.1142/9789812819833.
|
| [21] |
F. Natterer, The Mathematics of Computerized Tomography, reprint of the 1986 original. Classics in Applied Mathematics, 32. Society for Industrial and Applied Mathematics (SIAM), Philadelphia, PA, 2001.
doi: 10.1137/1.9780898719284.
|
| [22] |
M. Reed and B. Simon, Methods of Modern Mathematical Physics, I. Functional Analysis, Second edition. Academic Press, Inc. [Harcourt Brace Jovanovich, Publishers], New York, 1980.
|
| [23] |
F. Rellich, Perturbation Theory of Eigenvalue Problems, Assisted by J. Berkowitz. With a preface by Jacob T. Schwartz, Gordon and Breach Science Publishers, New York-London-Paris, 1969.
|
| [24] |
P. Stefanov and A. Tamasan, Uniqueness and non-uniqueness in inverse radiative transfer, Proc. Amer. Math. Soc., 137 (2009), 2335-2344.
doi: 10.1090/S0002-9939-09-09839-6.
|
Geometry of the
Layering of the domain