منابع مشابه
The square of the Weyl tensor can be negative
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It has been shown recently that there is a large class of supersymmetric solutions of five-dimensional supergravity which generalize the supersymmetric black ring solution of Elvang et al. This class involves arbitrary functions. We show that most of these solutions do not have smooth event horizons, so they do not provide examples of black objects with infinite amounts of “hair”.
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The management of traumatic disruption of the pelvic ring has become a focus of interest, the main question being whether such disruptions should be stabilised at operation. Stabilisation may be important for the survival of the patient, as has been suggested for femoral fractures, and it may also be desirable to improve the long-term functional results of such injuries. It is therefore necessa...
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We introduce higher order (polynomial) extensions of the unique (up to isomorphisms) non trivial central extension of the Heisenberg algebra. Using the boson representation of the latter, we construct the corresponding polynomial analogue of the Weyl C*-algebra and use this result to deduce the explicit form of the composition law of the associated generalization of the 1-dimensional Heisenberg...
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ژورنال
عنوان ژورنال: Proceedings of the American Mathematical Society
سال: 1989
ISSN: 0002-9939
DOI: 10.1090/s0002-9939-1989-0962247-0