A theorem of Cohen on parapolar spaces


We give an elementary proof of a critical lemma of Arjeh Cohen used in his fundamental paper giving an axiomatic characterization of Grassmann spaces of finite singular rank.

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Corresponding author

Correspondence to Ernest E. Shult.

Additional information

The second author is a Postdoctoral Fellow of the Fund for Scientific Research — Flanders (Belgium).

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Shult, E.E., Thas, K. A theorem of Cohen on parapolar spaces. Combinatorica 30, 435–444 (2010). https://doi.org/10.1007/s00493-010-2410-9

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Mathematics Subject Classification (2000)

  • 05B25
  • 05E20
  • 20B25
  • 20E26
  • 20E42
  • 51E12
  • 51E24