745 research outputs found
A perspective on non-commutative frame theory
This paper extends the fundamental results of frame theory to a
non-commutative setting where the role of locales is taken over by \'etale
localic categories. This involves ideas from quantale theory and from semigroup
theory, specifically Ehresmann semigroups, restriction semigroups and inverse
semigroups. We establish a duality between the category of complete restriction
monoids and the category of \'etale localic categories. The relationship
between monoids and categories is mediated by a class of quantales called
restriction quantal frames. This result builds on the work of Pedro Resende on
the connection between pseudogroups and \'etale localic groupoids but in the
process we both generalize and simplify: for example, we do not require
involutions and, in addition, we render his result functorial. We also project
down to topological spaces and, as a result, extend the classical adjunction
between locales and topological spaces to an adjunction between \'etale localic
categories and \'etale topological categories. In fact, varying morphisms, we
obtain several adjunctions. Just as in the commutative case, we restrict these
adjunctions to spatial-sober and coherent-spectral equivalences. The classical
equivalence between coherent frames and distributive lattices is extended to an
equivalence between coherent complete restriction monoids and distributive
restriction semigroups. Consequently, we deduce several dualities between
distributive restriction semigroups and spectral \'etale topological
categories. We also specialize these dualities for the setting where the
topological categories are cancellative or are groupoids. Our approach thus
links, unifies and extends the approaches taken in the work by Lawson and Lenz
and by Resende.Comment: 69 page
Green Economy: Regional Priorities
The article is dedicated to transforming the economy of Russian regions to a green economy, which is an essential factor for the sustainable development. This is important not only for Russia but the whole world because our country has the great natural capital and provides important environmental services that support the planet biosphere. Based on the analysis of economic, social and ecological statistical data and Human Development Index (HDI) we have shown that the development of Russian Federal Districts is very unbalanced and each Russian region has its own way to new economic model. For instance, it is necessary to increase the well-being in the North Caucasus Federal District, it is important to reach higher life expectancy at birth in the Siberian and the Far Eastern Districts. It is necessary to move from the «brown» economy to a green one by using the human capital (building a knowledge economy), by applying Best Available Technologies (Techniques), by investing in efficiency of use of natural resources and by increasing energy efficiency. The transition to a green economy will help to achieve social equity and the development of human potential; it helps to move from the exploitation of non-renewable natural capital to renewable human capital. All these socio-economic measures should give decoupling effect, make risks lower, reduce the exploitation of natural capital, stop the environmental degradation and prevent the ecological crisis. Transition to the green economic model has to be accompanied by new economic development indicators, which take into account social and environmental factors.The research was supported by the grant of the Russian Foundation for Basic Research No. 14-06-00075
The Liouville-type theorem for integrable Hamiltonian systems with incomplete flows
For integrable Hamiltonian systems with two degrees of freedom whose
Hamiltonian vector fields have incomplete flows, an analogue of the Liouville
theorem is established. A canonical Liouville fibration is defined by means of
an "exact" 2-parameter family of flat polygons equipped with certain pairing of
sides. For the integrable Hamiltonian systems given by the vector field
on where
is a complex polynomial in 2 variables, geometric properties of
Liouville fibrations are described.Comment: 6 page
Invariant means on Boolean inverse monoids
The classical theory of invariant means, which plays an important role in the
theory of paradoxical decompositions, is based upon what are usually termed
`pseudogroups'. Such pseudogroups are in fact concrete examples of the Boolean
inverse monoids which give rise to etale topological groupoids under
non-commutative Stone duality. We accordingly initiate the theory of invariant
means on arbitrary Boolean inverse monoids. Our main theorem is a
characterization of when a Boolean inverse monoid admits an invariant mean.
This generalizes the classical Tarski alternative proved, for example, by de la
Harpe and Skandalis, but using different methods
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