What is Boundary conditions: Definition and 415 Discussions

In mathematics, in the field of differential equations, a boundary value problem is a differential equation together with a set of additional constraints, called the boundary conditions. A solution to a boundary value problem is a solution to the differential equation which also satisfies the boundary conditions.
Boundary value problems arise in several branches of physics as any physical differential equation will have them. Problems involving the wave equation, such as the determination of normal modes, are often stated as boundary value problems. A large class of important boundary value problems are the Sturm–Liouville problems. The analysis of these problems involves the eigenfunctions of a differential operator.
To be useful in applications, a boundary value problem should be well posed. This means that given the input to the problem there exists a unique solution, which depends continuously on the input. Much theoretical work in the field of partial differential equations is devoted to proving that boundary value problems arising from scientific and engineering applications are in fact well-posed.
Among the earliest boundary value problems to be studied is the Dirichlet problem, of finding the harmonic functions (solutions to Laplace's equation); the solution was given by the Dirichlet's principle.

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  1. T

    Laplace's equation with unusual boundary conditions

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  2. M

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  3. S

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  4. M

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  5. V

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  6. A. Neumaier

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  7. N

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  8. Q

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  9. M

    MHB Transform Boundary Conditions w/ Diff. $g_{0}, g_{1}$

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  10. D

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  11. M

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  12. fluidistic

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  13. K

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  14. V

    Neumann Boundary Conditions question

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  15. K

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  16. Z

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  17. Y

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  18. E

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  19. M

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  20. M

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  21. B

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  22. L

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  23. Telemachus

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  24. jegues

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  26. T

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  27. K

    Boundary conditions for buckling of column

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  28. C

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  29. JK423

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  30. V

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  31. I

    Numerical FDM - wave equation - boundary conditions question

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  32. A

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  33. H

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  34. P

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  35. U

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  36. A

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  37. R

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  38. B

    Neumann Boundary Conditions for Heat Equation

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  39. H

    Boundary Conditions for an Airy Stress Function

    I am using Gaussian elimination to solve the airy stress function, but I am having difficulty implementing boundary conditions. A good synopsis on the problem of identifying boundary conditions is given here (section 5.2.1): http://solidmechanics.org/text/Chapter5_2/Chapter5_2.htm Given that...
  40. F

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  41. T

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  42. 0

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  43. D

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  44. A

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  45. A

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  46. I

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  47. H

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  48. R

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  49. Z

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  50. Spinnor

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