## Summary

Let L_{ε}u and L_{
0
}v be the elliptic and “backward” heat operators defined by*(1.1)* and*(1.2)*, respectively. The following question is considered for a pair of “non-well posed” initial-boundary value problems for L_{ε} and L_{
0
}: if u and v are the respective solutions, under what restrictions on the classes of admissible solutions and in what sense, if any, does u converge to v as ɛ →*0*?

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## Additional information

This research was supported in part by the National Science Foundation Grant No. GP 5882 with Cornell University.

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### Cite this article

Payne, L.E., Sather, D. On singular perturbation in non well posed problems.
*Annali di Matematica* **75, **219–230 (1967). https://doi.org/10.1007/BF02416803

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### Keywords

- Singular Perturbation
- Admissible Solution
- Heat Operator
- Respective Solution