# American Institute of Mathematical Sciences

June  2015, 2(2): 143-164. doi: 10.3934/jcd.2015001

## A posteriori error bounds for two point boundary value problems: A green's function approach

 1 Program in Applied Mathematics, The University of Arizona, Tucson, Arizona 85721, United States

Received  January 2015 Revised  August 2015 Published  May 2016

We present a computer assisted method for generating existence proofs and a posteriori error bounds for solutions to two point boundary value problems (BVPs). All truncation errors are accounted for and, if combined with interval arithmetic to bound the rounding errors, the computer generated results are mathematically rigorous. The method is formulated for $n$-dimensional systems and does not require any special form for the vector field of the differential equation. It utilizes a numerically generated approximation to the BVP fundamental solution and Green's function and thus can be applied to stable BVPs whose initial value problem is unstable. The utility of the method is demonstrated on a pair of singularly perturbed model BVPs and by using it to rigorously show the existence of a periodic orbit in the Lorenz system.
Citation: Jeremiah Birrell. A posteriori error bounds for two point boundary value problems: A green's function approach. Journal of Computational Dynamics, 2015, 2 (2) : 143-164. doi: 10.3934/jcd.2015001
##### References:
 [1] D. Ambrosi, G. Arioli and H. Koch, A homoclinic solution for excitation waves on a contractile substratum,, SIAM Journal on Applied Dynamical Systems, 11 (2012), 1533. doi: 10.1137/12087654X. Google Scholar [2] G. Arioli and H. Koch, Existence and stability of traveling pulse solutions of the FitzHugh-Nagumo equation,, Nonlinear Analysis: Theory, 113 (2015), 51. doi: 10.1016/j.na.2014.09.023. Google Scholar [3] U. Ascher and L. Petzold, Computer Methods for Ordinary Differential Equations and Differential-Algebraic Equations,, Society for Industrial and Applied Mathematics (SIAM, (3600). doi: 10.1137/1.9781611971392. Google Scholar [4] P.-O. Åsén, Stability of Plane Couette Flow and Pipe Poiseuille Flow,, PhD thesis, (2007). Google Scholar [5] B. A. Coomes, H. Koçak and K. J. Palmer, Rigorous computational shadowing of orbits of ordinary differential equations,, Numerische Mathematik, 69 (1995), 401. doi: 10.1007/s002110050100. Google Scholar [6] Y. Eidelman, V. Milman and A. Tsolomitis, Functional Analysis: An Introduction,, Graduate studies in mathematics, (2004). doi: 10.1090/gsm/066. Google Scholar [7] C. Fefferman and R. de la Llave, Relativistic stability of matter-I,, I. Rev. Mat. Iberoamericana, 2 (1986), 119. doi: 10.4171/RMI/30. Google Scholar [8] O. Fogelklou, W. Tucker and G. Kreiss, A computer-assisted proof of the existence of traveling wave solutions to the scalar euler equations with artificial viscosity,, Nonlinear Differential Equations and Applications NoDEA, 19 (2012), 97. doi: 10.1007/s00030-011-0120-7. Google Scholar [9] O. Fogelklou, W. Tucker, G. Kreiss and M. Siklosi, A computer-assisted proof of the existence of solutions to a boundary value problem with an integral boundary condition,, Communications in Nonlinear Science and Numerical Simulation, 16 (2011), 1227. doi: 10.1016/j.cnsns.2010.07.008. Google Scholar [10] G. Folland, Real Analysis: Modern Techniques and Their Applications,, A Wiley-Interscience Publication. John Wiley & Sons, (1984). Google Scholar [11] Z. Galias and P. Zgliczyski, Computer assisted proof of chaos in the Lorenz equations,, Physica D: Nonlinear Phenomena, 115 (1998), 165. doi: 10.1016/S0167-2789(97)00233-9. Google Scholar [12] M. Göhlen, M. Plum and J. Schröder, A programmed algorithm for existence proofs for two-point boundary value problems,, Computing, 44 (1990), 91. doi: 10.1007/BF02241862. Google Scholar [13] A. Hungria, J.-P. Lessard and J. D. M. James, Rigorous numerics for analytic solutions of differential equations: The radii polynomial approach,, Math. Comp., 85 (2016), 1427. doi: 10.1090/mcom/3046. Google Scholar [14] L. Jaulin, Applied Interval Analysis: With Examples in Parameter and State Estimation, Robust Control and Robotics,, no. v. 1 in Applied Interval Analysis: With Examples in Parameter and State Estimation, (2001). doi: 10.1007/978-1-4471-0249-6. Google Scholar [15] L. Kantorovich and G. Akilov, Functional Analysis in Normed Spaces,, International series of monographs in pure and applied mathematics, (1964). Google Scholar [16] R. B. Kearfott, Interval computations: Introduction, uses, and resources,, Euromath Bulletin, 2 (1996), 95. Google Scholar [17] G. Kedem, A posteriori error bounds for two-point boundary value problems,, SIAM Journal on Numerical Analysis, 18 (1981), 431. doi: 10.1137/0718028. Google Scholar [18] H. Koch, A. Schenkel and P. Wittwer, Computer-assisted proofs in analysis and programming in logic: A case study,, SIAM Review, 38 (1996), 565. doi: 10.1137/S0036144595284180. Google Scholar [19] J. Lee and L. Greengard, A fast adaptive numerical method for stiff two-point boundary value problems,, SIAM Journal on Scientific Computing, 18 (1997), 403. doi: 10.1137/S1064827594272797. Google Scholar [20] J.-P. Lessard, J. Mireles James and C. Reinhardt, Computer assisted proof of transverse saddle-to-saddle connecting orbits for first order vector fields,, Journal of Dynamics and Differential Equations, 26 (2014), 267. doi: 10.1007/s10884-014-9367-0. Google Scholar [21] J.-P. Lessard and C. Reinhardt, Rigorous numerics for nonlinear differential equations using Chebyshev series,, SIAM Journal on Numerical Analysis, 52 (2014), 1. doi: 10.1137/13090883X. Google Scholar [22] M. A. McCarthy and R. A. Tapia, Computable a posteriori $L_\infty$-error bounds for the approximate solution of two-point boundary value problems,, SIAM Journal on Numerical Analysis, 12 (1975), 919. doi: 10.1137/0712068. Google Scholar [23] R. Moore, Methods and Applications of Interval Analysis,, Studies in Applied and Numerical Mathematics, (1979). Google Scholar [24] R. Moore, R. Kearfott and M. Cloud, Introduction to Interval Analysis,, Cambridge University Press, (2009). doi: 10.1137/1.9780898717716. Google Scholar [25] K. Nagatou, N. Yamamoto and M. Nakao, An approach to the numerical verification of solutions for nonlinear elliptic problems with local uniqueness,, Numerical Functional Analysis and Optimization, 20 (1999), 543. doi: 10.1080/01630569908816910. Google Scholar [26] M. T. Nakao, Solving nonlinear parabolic problems with result verification. Part I: One-space dimensional case,, Journal of Computational and Applied Mathematics, 38 (1991), 323. doi: 10.1016/0377-0427(91)90179-N. Google Scholar [27] M. T. Nakao, A numerical verification method for the existence of weak solutions for nonlinear boundary value problems,, Journal of Mathematical Analysis and Applications, 164 (1992), 489. doi: 10.1016/0022-247X(92)90129-2. Google Scholar [28] M. T. Nakao, Numerical verification methods for solutions of ordinary and partial differential equations,, Numerical Functional Analysis and Optimization, 22 (2001), 321. doi: 10.1081/NFA-100105107. Google Scholar [29] N. Nedialkov, K. Jackson and G. Corliss, Validated solutions of initial value problems for ordinary differential equations,, Applied Mathematics and Computation, 105 (1999), 21. doi: 10.1016/S0096-3003(98)10083-8. Google Scholar [30] M. Plum, Computer-assisted existence proofs for two-point boundary value problems,, Computing, 46 (1991), 19. doi: 10.1007/BF02239009. Google Scholar [31] M. Plum, Existence and multiplicity proofs for semilinear elliptic boundary value problems by computer assistance,, Jahresbericht der Deutschen Mathematiker Vereinigung, 110 (2008), 19. Google Scholar [32] S. Rump, INTLAB - INTerval LABoratory,, in Developments in Reliable Computing (ed. T. Csendes), (1999), 77. doi: 10.1007/978-94-017-1247-7_7. Google Scholar [33] A. Takayasu, S. Oishi and T. Kubo, Numerical existence theorem for solutions of two-point boundary value problems of nonlinear differential equations,, Nonlinear Theory and Its Applications, 1 (2010), 105. doi: 10.1587/nolta.1.105. Google Scholar [34] W. Tucker, Validated Numerics: A Short Introduction to Rigorous Computations,, Princeton University Press, (2011). Google Scholar [35] W. Tucker, The Lorenz attractor exists,, Comptes Rendus de l'Académie des Sciences - Series I - Mathematics, 328 (1999), 1197. doi: 10.1016/S0764-4442(99)80439-X. Google Scholar [36] M. Urabe, Galerkin's procedure for nonlinear periodic systems,, Archive for Rational Mechanics and Analysis, 20 (1965), 120. doi: 10.1007/BF00284614. Google Scholar [37] J. van den Berg, J. Mireles-James, J. Lessard and K. Mischaikow, Rigorous numerics for symmetric connecting orbits: Even homoclinics of the Gray-Scott equation,, SIAM Journal on Mathematical Analysis, 43 (2011), 1557. doi: 10.1137/100812008. Google Scholar [38] J. B. van den Berg, C. M. Groothedde and J. F. Williams, Rigorous computation of a radially symmetric localized solution in a Ginzburg-Landau problem,, SIAM Journal on Applied Dynamical Systems, 14 (2015), 423. doi: 10.1137/140987973. Google Scholar [39] Y. Watanabe, M. Plum and M. T. Nakao, A computer-assisted instability proof for the Orr-Sommerfeld problem with Poiseuille flow,, ZAMM-Journal of Applied Mathematics and Mechanics/Zeitschrift für Angewandte Mathematik und Mechanik, 89 (2009), 5. doi: 10.1002/zamm.200700158. Google Scholar [40] N. Yamamoto, A numerical verification method for solutions of boundary value problems with local uniqueness by Banach's fixed-point theorem,, SIAM Journal on Numerical Analysis, 35 (1998), 2004. doi: 10.1137/S0036142996304498. Google Scholar [41] P. Zgliczynski, Computer assisted proof of chaos in the Rössler equations and in the Hénon map,, Nonlinearity, 10 (1997), 243. doi: 10.1088/0951-7715/10/1/016. Google Scholar

show all references

##### References:
 [1] D. Ambrosi, G. Arioli and H. Koch, A homoclinic solution for excitation waves on a contractile substratum,, SIAM Journal on Applied Dynamical Systems, 11 (2012), 1533. doi: 10.1137/12087654X. Google Scholar [2] G. Arioli and H. Koch, Existence and stability of traveling pulse solutions of the FitzHugh-Nagumo equation,, Nonlinear Analysis: Theory, 113 (2015), 51. doi: 10.1016/j.na.2014.09.023. Google Scholar [3] U. Ascher and L. Petzold, Computer Methods for Ordinary Differential Equations and Differential-Algebraic Equations,, Society for Industrial and Applied Mathematics (SIAM, (3600). doi: 10.1137/1.9781611971392. Google Scholar [4] P.-O. Åsén, Stability of Plane Couette Flow and Pipe Poiseuille Flow,, PhD thesis, (2007). Google Scholar [5] B. A. Coomes, H. Koçak and K. J. Palmer, Rigorous computational shadowing of orbits of ordinary differential equations,, Numerische Mathematik, 69 (1995), 401. doi: 10.1007/s002110050100. Google Scholar [6] Y. Eidelman, V. Milman and A. Tsolomitis, Functional Analysis: An Introduction,, Graduate studies in mathematics, (2004). doi: 10.1090/gsm/066. Google Scholar [7] C. Fefferman and R. de la Llave, Relativistic stability of matter-I,, I. Rev. Mat. Iberoamericana, 2 (1986), 119. doi: 10.4171/RMI/30. Google Scholar [8] O. Fogelklou, W. Tucker and G. Kreiss, A computer-assisted proof of the existence of traveling wave solutions to the scalar euler equations with artificial viscosity,, Nonlinear Differential Equations and Applications NoDEA, 19 (2012), 97. doi: 10.1007/s00030-011-0120-7. Google Scholar [9] O. Fogelklou, W. Tucker, G. Kreiss and M. Siklosi, A computer-assisted proof of the existence of solutions to a boundary value problem with an integral boundary condition,, Communications in Nonlinear Science and Numerical Simulation, 16 (2011), 1227. doi: 10.1016/j.cnsns.2010.07.008. Google Scholar [10] G. Folland, Real Analysis: Modern Techniques and Their Applications,, A Wiley-Interscience Publication. John Wiley & Sons, (1984). Google Scholar [11] Z. Galias and P. Zgliczyski, Computer assisted proof of chaos in the Lorenz equations,, Physica D: Nonlinear Phenomena, 115 (1998), 165. doi: 10.1016/S0167-2789(97)00233-9. Google Scholar [12] M. Göhlen, M. Plum and J. Schröder, A programmed algorithm for existence proofs for two-point boundary value problems,, Computing, 44 (1990), 91. doi: 10.1007/BF02241862. Google Scholar [13] A. Hungria, J.-P. Lessard and J. D. M. James, Rigorous numerics for analytic solutions of differential equations: The radii polynomial approach,, Math. Comp., 85 (2016), 1427. doi: 10.1090/mcom/3046. Google Scholar [14] L. Jaulin, Applied Interval Analysis: With Examples in Parameter and State Estimation, Robust Control and Robotics,, no. v. 1 in Applied Interval Analysis: With Examples in Parameter and State Estimation, (2001). doi: 10.1007/978-1-4471-0249-6. Google Scholar [15] L. Kantorovich and G. Akilov, Functional Analysis in Normed Spaces,, International series of monographs in pure and applied mathematics, (1964). Google Scholar [16] R. B. Kearfott, Interval computations: Introduction, uses, and resources,, Euromath Bulletin, 2 (1996), 95. Google Scholar [17] G. Kedem, A posteriori error bounds for two-point boundary value problems,, SIAM Journal on Numerical Analysis, 18 (1981), 431. doi: 10.1137/0718028. Google Scholar [18] H. Koch, A. Schenkel and P. Wittwer, Computer-assisted proofs in analysis and programming in logic: A case study,, SIAM Review, 38 (1996), 565. doi: 10.1137/S0036144595284180. Google Scholar [19] J. Lee and L. Greengard, A fast adaptive numerical method for stiff two-point boundary value problems,, SIAM Journal on Scientific Computing, 18 (1997), 403. doi: 10.1137/S1064827594272797. Google Scholar [20] J.-P. Lessard, J. Mireles James and C. Reinhardt, Computer assisted proof of transverse saddle-to-saddle connecting orbits for first order vector fields,, Journal of Dynamics and Differential Equations, 26 (2014), 267. doi: 10.1007/s10884-014-9367-0. Google Scholar [21] J.-P. Lessard and C. Reinhardt, Rigorous numerics for nonlinear differential equations using Chebyshev series,, SIAM Journal on Numerical Analysis, 52 (2014), 1. doi: 10.1137/13090883X. Google Scholar [22] M. A. McCarthy and R. A. Tapia, Computable a posteriori $L_\infty$-error bounds for the approximate solution of two-point boundary value problems,, SIAM Journal on Numerical Analysis, 12 (1975), 919. doi: 10.1137/0712068. Google Scholar [23] R. Moore, Methods and Applications of Interval Analysis,, Studies in Applied and Numerical Mathematics, (1979). Google Scholar [24] R. Moore, R. Kearfott and M. Cloud, Introduction to Interval Analysis,, Cambridge University Press, (2009). doi: 10.1137/1.9780898717716. Google Scholar [25] K. Nagatou, N. Yamamoto and M. Nakao, An approach to the numerical verification of solutions for nonlinear elliptic problems with local uniqueness,, Numerical Functional Analysis and Optimization, 20 (1999), 543. doi: 10.1080/01630569908816910. Google Scholar [26] M. T. Nakao, Solving nonlinear parabolic problems with result verification. Part I: One-space dimensional case,, Journal of Computational and Applied Mathematics, 38 (1991), 323. doi: 10.1016/0377-0427(91)90179-N. Google Scholar [27] M. T. Nakao, A numerical verification method for the existence of weak solutions for nonlinear boundary value problems,, Journal of Mathematical Analysis and Applications, 164 (1992), 489. doi: 10.1016/0022-247X(92)90129-2. Google Scholar [28] M. T. Nakao, Numerical verification methods for solutions of ordinary and partial differential equations,, Numerical Functional Analysis and Optimization, 22 (2001), 321. doi: 10.1081/NFA-100105107. Google Scholar [29] N. Nedialkov, K. Jackson and G. Corliss, Validated solutions of initial value problems for ordinary differential equations,, Applied Mathematics and Computation, 105 (1999), 21. doi: 10.1016/S0096-3003(98)10083-8. Google Scholar [30] M. Plum, Computer-assisted existence proofs for two-point boundary value problems,, Computing, 46 (1991), 19. doi: 10.1007/BF02239009. Google Scholar [31] M. Plum, Existence and multiplicity proofs for semilinear elliptic boundary value problems by computer assistance,, Jahresbericht der Deutschen Mathematiker Vereinigung, 110 (2008), 19. Google Scholar [32] S. Rump, INTLAB - INTerval LABoratory,, in Developments in Reliable Computing (ed. T. Csendes), (1999), 77. doi: 10.1007/978-94-017-1247-7_7. Google Scholar [33] A. Takayasu, S. Oishi and T. Kubo, Numerical existence theorem for solutions of two-point boundary value problems of nonlinear differential equations,, Nonlinear Theory and Its Applications, 1 (2010), 105. doi: 10.1587/nolta.1.105. Google Scholar [34] W. Tucker, Validated Numerics: A Short Introduction to Rigorous Computations,, Princeton University Press, (2011). Google Scholar [35] W. Tucker, The Lorenz attractor exists,, Comptes Rendus de l'Académie des Sciences - Series I - Mathematics, 328 (1999), 1197. doi: 10.1016/S0764-4442(99)80439-X. Google Scholar [36] M. Urabe, Galerkin's procedure for nonlinear periodic systems,, Archive for Rational Mechanics and Analysis, 20 (1965), 120. doi: 10.1007/BF00284614. Google Scholar [37] J. van den Berg, J. Mireles-James, J. Lessard and K. Mischaikow, Rigorous numerics for symmetric connecting orbits: Even homoclinics of the Gray-Scott equation,, SIAM Journal on Mathematical Analysis, 43 (2011), 1557. doi: 10.1137/100812008. Google Scholar [38] J. B. van den Berg, C. M. Groothedde and J. F. Williams, Rigorous computation of a radially symmetric localized solution in a Ginzburg-Landau problem,, SIAM Journal on Applied Dynamical Systems, 14 (2015), 423. doi: 10.1137/140987973. Google Scholar [39] Y. Watanabe, M. Plum and M. T. Nakao, A computer-assisted instability proof for the Orr-Sommerfeld problem with Poiseuille flow,, ZAMM-Journal of Applied Mathematics and Mechanics/Zeitschrift für Angewandte Mathematik und Mechanik, 89 (2009), 5. doi: 10.1002/zamm.200700158. Google Scholar [40] N. Yamamoto, A numerical verification method for solutions of boundary value problems with local uniqueness by Banach's fixed-point theorem,, SIAM Journal on Numerical Analysis, 35 (1998), 2004. doi: 10.1137/S0036142996304498. Google Scholar [41] P. Zgliczynski, Computer assisted proof of chaos in the Rössler equations and in the Hénon map,, Nonlinearity, 10 (1997), 243. doi: 10.1088/0951-7715/10/1/016. Google Scholar
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