Computations of orbits for the Lubin–Tate ring

  • Agnès BeaudryEmail author
  • Naiche Downey
  • Connor McCranie
  • Luke Meszar
  • Andy Riddle
  • Peter Rock


We take a direct approach to computing the orbits for the action of the automorphism group \(\mathbb {G}_2\) of the Honda formal group law of height 2 on the associated Lubin–Tate rings \(R_2\). We prove that \((R_2/p)_{\mathbb {G}_2} \cong \mathbb {F}_p\). The result is new for \(p=2\) and \(p=3\). For primes \(p\ge 5\), the result is a consequence of computations of Shimomura and Yabe and has been reproduced by Kohlhaase using different methods.


Honda formal group law Lubin-Tate ring Morava E-theory Morava stabilizer group Chromatic Vanishing Conjecture 



We thank some of the usual suspects for useful conversations: Tobias Barthel, Mark Behrens, Paul Goerss, Hans-Werner Henn, Mike Hopkins, Niko Naumann and Vesna Stojanoska. We also thank the referee and the editors their input.


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Copyright information

© Tbilisi Centre for Mathematical Sciences 2018

Authors and Affiliations

  • Agnès Beaudry
    • 1
    Email author
  • Naiche Downey
    • 1
  • Connor McCranie
    • 1
  • Luke Meszar
    • 1
  • Andy Riddle
    • 1
  • Peter Rock
    • 1
  1. 1.Department of MathematicsUniversity of Colorado at BoulderBoulderUSA

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