X iv :c on dm at /9 90 53 38 v1 2 3 M ay 1 99 9 Topological Gauge Theory Of General Weitzenböck Manifolds Of Dislocations In Crystals Y. C. Huang B. L. Lin S. Li M. X. Shao Department of Applied Physics, Beijing Polytechnic University, Beijing,100022, P. R. China Department of Transportation Management Engenerring, Northean Jiaotong University, Beijing, 100044, P. R.China Institute of Theoretic...

We show that the universal theory of torsion groups is strongly contained in the universal theory of finite groups. This answers a question of Dyson. We also prove that the universal theory of some natural classes of torsion groups is undecidable. Finally we observe that the universal theory of the class of hyperbolic groups is undecidable and use this observation to construct a lacunary hyperb...

Woody feedstocks will play a critical role in meeting the demand for biomass-based energy products in the US. We developed an integrated model using comparable system boundaries and common set of assumptions to ascertain unit cost and greenhouse gas (GHG) intensity of electricity and ethanol derived from slash pine (Pinus elliottii) at the production and consumption levels by considering existi...

we first characterize $tau$-complemented modules with relative (pre)-covers. we also introduce an extending module relative to $tau$-pure submodules on a hereditary torsion theory $tau$ and give its relationship with $tau$-complemented modules.

We investigate the role of the torsion field at the quantum level. One-loop counterterms are calculated in the theory with terms quadratic in the torsion field. We have shown that the theory is finite at the one-loop level. 1 E-mail: [email protected] Supported in part by RFFR grant # 94-02 03665-a and ISF grant # RFL300 E-mail: [email protected]