منابع مشابه
Weights at the Bottom Matter When the Top is Heavy
Proving super-polynomial lower bounds against depth-2 threshold circuits of the form THR ◦THR is a well-known open problem that represents a frontier of our understanding in boolean circuit complexity. By contrast, exponential lower bounds on the size of THR◦MAJ circuits were shown by Razborov and Sherstov [31] even for computing functions in depth-3 AC. Yet, no separation among the two depth-2...
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Experiment shows that the top quark is far heavier than the other elementary fermions. This finding has stimulated research on theories of electroweak and flavor symmetry breaking that include physics beyond the standard model. Efforts to accommodate a heavy top quark within existing frameworks have revealed constraints on model-building. Other investigations have started from the premise that ...
متن کاملThe Heavy Top Quark and Supersymmetry * † Disclaimer
Three aspects of supersymmetric theories are discussed: electroweak symmetry breaking, the issues of flavor, and gauge unification. The heavy top quark plays an important, sometimes dominant, role in each case. Additional symmetries lead to extensions of the standard model which can provide an understanding for many of the outstanding problems of particle physics. A broken supersymmetric extens...
متن کاملThe Heavy Top Quark And Supersymmetry
Three aspects of supersymmetric theories are discussed: electroweak symmetry breaking, the issues of avor, and gauge uni cation. The heavy top quark plays an important, sometimes dominant, role in each case. Additional symmetries lead to extensions of the Standard Model which can provide an understanding for many of the outstanding problems of particle physics. A broken supersymmetric extension...
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Climate is one of the main structuring forces in natural ecosystems (Richardson and Schoeman, 2004), and anthropogenic climate change is regarded as an important driver of changes in the range and abundance of species as well as community composition, not least in marine ecosystems (Poloczanska et al., 2013). There are two overall mechanisms by which climate change can affect range and abundanc...
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ژورنال
عنوان ژورنال: BioScience
سال: 1973
ISSN: 0006-3568,1525-3244
DOI: 10.2307/1296495