9.43 (1984)

Partially Solved

a) The group $G$ described in the solution of problem 8.73 enables us to construct a projective plane of order 3 in which the lines are the elements of any conjugacy class of subgroups of order $2 \cdot 5 \cdot 7 \cdot 11$ together with four lines added in a natural way. In a similar way, we can construct a projective plane of order $p^n$ for any prime $p$ and any positive integer $n$. Does the resulting projective plane have the Galois property?

b) The group $G$ indicated in (N. D. Podufalov, Abstracts of the 9th All–Union Symp. on Group Theory, Moscow, 1984, 113–114 (Russian)) allows us to construct a projective plane of order 3: one can take as lines any class of subgroups of order $2 \cdot 5 \cdot 11 \cdot 17$ conjugate under $S$ and add four more lines in a natural way. In a similar way, one can construct projective planes of order $p^n$ for any prime $p$ and any natural $n$. Could this method be adapted for constructing new planes?

Progress

a) Not always. The answer is affirmative for $n = 1$. But for $n > 1$ the planes in question may not have the Galois property. For example, if there exists a near-field of $p^n$ elements, then among the planes of order $p^n$ indicated there will definitely be some non-Desarguesian planes. (N. D. Podufalov, Letter of November, 24, 1986.)

Comments

All comments are the responsibility of the user. Comments appearing on this page are not verified for correctness. Please keep posts mathematical and on topic. If you want to submit a proof (or a partial proof), please use the dedicated proof submission form rather than posting it in the comments.
Order by newest first or oldest first.

No comments yet. Be the first to comment.

Proof claims

Proof claims are the responsibility of the submitter. Appearance here does not mean the claim has been checked for mathematical correctness. Moderators only screen for spam, abuse, and obviously low-effort submissions.

No proof claims yet.