The Impact of Monotonicity Formulas in Regularity of Free Boundaries

  • Henrik Shahgholian
Part of the Progress in Mathematics book series (PM, volume 202)


In this note we give a survey on recent developments in the reg­ularity of free boundaries of obstacle type in absence of the obstacle, giving rise to solutions that may change sign. The focus is on two techniques, the monotonicity formulas and global versus local analysis.


Harmonic Function Free Boundary Global Solution Free Boundary Problem Obstacle Problem 
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Copyright information

© Springer Basel AG 2001

Authors and Affiliations

  • Henrik Shahgholian
    • 1
  1. 1.Department of MathematicsRoyal Institute of TechnologyStockholmSweden

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