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Jul 14, 2017 at 22:16 history bumped CommunityBot This question has answers that may be good or bad; the system has marked it active so that they can be reviewed.
Jun 14, 2017 at 20:35 answer added Pietro Paparella timeline score: 2
Apr 13, 2017 at 12:58 history edited CommunityBot
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Feb 17, 2015 at 15:44 comment added subshift Right now the best I can do is to enumerate all the matrices (using the trace constraint) and test them one by one... Can anyone think of a less stupid approach?
Feb 17, 2015 at 15:42 comment added subshift Gerry, I haven't looked at it for hours but it doesn't seem to be obvious even for $2\times2$ matrices.
Feb 17, 2015 at 15:41 comment added subshift David, unfortunately I would like to avoid the additional zero eigenvalues. Is this question open even without the primitivity assumption? Thanks for the very interesting articles!
Feb 17, 2015 at 0:10 comment added David Handelman It would be fascinating to obtain a criterion, let alone an efficient one. Do you permit adding extra zeros as eigenvalues (that is, replacing $p$ by $X^k p$)? Over the reals, it is possible to do this (with criteria in terms of traces of powers, see Boyle & Handelman cited in the reference you cited). Note that $(x-2)(x-1)$ cannot be realized (in your strong sense), but $x(x-2)(x-1)$ can. Reference is another paper by Mike B and me, Algebraic shift equivalence and primitive matrices, tams (1993), which deals mostly with realization over the nonnegative integers.
Feb 16, 2015 at 22:28 comment added Gerry Myerson Can you do the case $n=2$?
Feb 16, 2015 at 16:25 history asked subshift CC BY-SA 3.0