Complex sentence: In string theory, K-theory has been conjectured to classify the allowed Ramond-Ramond field strengths and also of the charges of stable D-branes by Ruben Minasian and Gregory Moore in hep-th/9710230.
Split into simpler sentences: In string theory, K-theory has been conjectured to classify the allowed Ramond-Ramond field strengths and also of the charges of stable D-branes. This conjecture, applied to D-brane charges, was first proposed by Ruben Minasian and Gregory Moore in hep-th/9710230.