Browsing 2011 by MSC "03"

Now showing items 1-4 of 4

    • Definable orthogonality classes in accessible categories are small 

      [OWP-2011-14] Bagaria, Joan; Casacuberta, Carles; Mathias, Adrian R. D.; Rosický, Jiří (Mathematisches Forschungsinstitut Oberwolfach, 2011-05-15)
      We lower substantially the strength of the assumptions needed for the validity of certain results in category theory and homotopy theory which were known to follow from Vopenka's principle. We prove that the necessary ...

    • Dominance and Transmissions in Supertropical Valuation Theory 

      [OWP-2011-07] Izhakian, Zur; Knebusch, Manfred; Rowen, Louis (Mathematisches Forschungsinstitut Oberwolfach, 2011)
      This paper is a sequel of [IKR1], where we defined supervaluations on a commutative ring $R$ and studied a dominance relation $\Phi >= v$ between supervaluations $\varphi$ and $\upsilon$ on $R$, aiming at an enrichment of ...

    • Monoid valuations and value ordered supervaluations 

      [OWP-2011-17] Izhakian, Zur; Knebusch, Manfred; Rowen, Louis (Mathematisches Forschungsinstitut Oberwolfach, 2011)
      We complement two papers on supertropical valuation theory ([IKR1], [IKR2]) by providing natural examples of m-valuations (= monoid valuations), after that of supervaluations and transmissions between them. The supervaluations ...

    • New representations of matroids and generalizations 

      [OWP-2011-18] Izhakian, Zur; Rhodes, John L. (Mathematisches Forschungsinstitut Oberwolfach, 2011)
      We extend the notion of matroid representations by matrices over fields by considering new representations of matroids by matrices over finite semirings, more precisely over the boolean and the superboolean semirings. This ...