9,791 research outputs found
The Ricci flow in a class of solvmanifolds
In this paper, we study the Ricci flow of solvmanifolds whose Lie algebra has
an abelian ideal of codimension one, by using the bracket flow. We prove that
solutions to the Ricci flow are immortal, the omega-limit of bracket flow
solutions is a single point, and that for any sequence of times there exists a
subsequence in which the Ricci flow converges, in the pointed topology, to a
manifold which is locally isometric to a flat manifold. We give a functional
which is non-increasing along a normalized bracket flow that will allow us to
prove that given a sequence of times, one can extract a subsequence converging
to an algebraic soliton, and to determine which of these limits are flat.
Finally, we use these results to prove that if a Lie group in this class admits
a Riemannian metric of negative sectional curvature, then the curvature of any
Ricci flow solution will become negative in finite time.Comment: 16 pages, 1 figur
The Services Sector in the Philippines
This paper studies the traded services in the Philippines with an emphasis on the analysis of government intervention. It examines the pattern of trade in services as well as provides the link of the former to the Philippine domestic economic structure. Details of the regulation and protection of traded services are also presented and analyzed in terms of government policies, levels of protection and economic implications. Some prospects for policy cooperation in traded services are suggested.services sector, service delivery
Homogeneous Ricci solitons in low dimensions
In this article we classify expanding homogeneous Ricci solitons up to
dimension 5, according to their presentation as homogeneous spaces. We obtain
that they are all isometric to solvsolitons, and this in particular implies
that the generalized Alekseevskii conjecture holds in these dimensions. In
addition, we prove that the conjecture holds in dimension 6 provided the
transitive group is not semisimple.Comment: 20 pages, 3 tables; Appendix by Jorge Laure
The Economic and Social Impact of Tourism
This paper analyzes the economic and social impact of tourism in Pagsanjan in which tourism development project is located. Results show that the project’s various significant impacts include increases in employment and income and stimulation of political and women’s participation. While its impact on environment and on the people’s social life has been a mixture of positive and negative results, its impact on income distribution has been trifling. To maximize the tourism multiplier, the paper encourages the collaboration of the tourism project with other programs devised to boost the capacity of the local economy. Tourism manpower training agenda should include training for women skills while tourism promotions should move from sex-oriented markets to prevent several disorientations in the cultural values of the tourism industries.tourism
Combinatorics of lattice paths with and without spikes
We derive a series of results on random walks on a d-dimensional hypercubic
lattice (lattice paths). We introduce the notions of terse and simple paths
corresponding to the path having no backtracking parts (spikes). These paths
label equivalence classes which allow a rearrangement of the sum over paths.
The basic combinatorial quantities of this construction are given. These
formulas are useful when performing strong coupling (hopping parameter)
expansions of lattice models. Some applications are described.Comment: Latex. 25 page
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