For more information about this meeting, contact Stephen Simpson.
| Title: | Invariant measures, computability, and reverse mathematics |
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| Seminar: | Logic Seminar |
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| Speaker: | Stephen G. Simpson, Pennsylvania State University |
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| Abstract: |
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| Let S be the unit circle. We construct a computable homeomorphism f: S --> S such that no computable probability measure on S is invariant under f. This construction is due to Mathieu Hoyrup and Cristobal Rojas. We extend their method to prove the following result of reverse mathematics: WKL_0 is equivalent over RCA_0 to the statement that for every Z-action on a compact metric space there exists an invariant probability measure. |
Room Reservation Information
| Room Number: | MB315 |
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| Date: | 02 / 16 / 2010 |
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| Time: | 02:30pm - 03:45pm |
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