A Local Ring Is CM If and Only If Its Residue Field Has a CM Syzygy
نویسندگان
چکیده
منابع مشابه
Embedding If and Only If
Compounds of indicative conditionals present some puzzling phenomena. Perhaps most striking, some nested indicative conditionals are uninterpretable. Proponents of NTV hold that indicative conditionals do not have truth values, and they use this to explain why nested indicative conditionals are sometimes uninterpretable: the embedded conditional does not provide the truth conditions needed by t...
متن کاملA Negative Conjunctive Query is Easy if and only if it is Beta-Acyclic
It is known that the data complexity of a Conjunctive Query (CQ) is determined only by the way its variables are shared between atoms, reflected by its hypergraph. In particular, Yannakakis [18, 3] proved that a CQ is decidable in linear time when it is α-acyclic, i.e. its hypergraph is α-acyclic; Bagan et al. [2] even state: Any CQ is decidable in linear time iff it is α-acyclic. (under certai...
متن کاملMarkets are efficient if and only if P = NP
I prove that if markets are efficient, meaning current prices fully reflect all information available in past prices, then P = NP , meaning every computational problem whose solution can be verified in polynomial time can also be solved in polynomial time. I also prove the converse by showing how we can “program” the market to solve NP -complete problems. Since P probably does not equal NP , ma...
متن کاملIf I Only Had A Brane!
This thesis starts with a review of supersymmetric solutions of 11-dimensional supergravity; in particular flat M-branes and BPS configurations which can be constructed from them. The harmonic function rule is discussed and it is shown why this cannot be expected to apply to intersecting brane configurations where the intersection is localised. A new class of spacetimes is needed to cover these...
متن کاملOnTruth-Conditions for If (but Not Quite Only If )
For—according to the lore—any attempt at pullingoff this featwill reduce themtomaterial implicationand that is decidedlynot agoodwayof assigning truth-conditions to ordinary indicative if s. That is too bad since it seems like they are bounded from above by strict implication (they are true when their antecedents straight out imply their consequents), are bounded from below by material implicat...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Tokyo Journal of Mathematics
سال: 1991
ISSN: 0387-3870
DOI: 10.3836/tjm/1270130388