12,075,828 research outputs found
Influence of Anthropogenic Climate Change on the Ecophysiology of the Cold Water Coral Lophelia pertusa = Einfluss des anthropogenen Klimawandels auf die Ökophysiologie der Kaltwasserkoralle Lophelia pertusa
Monographic work describing the cultivation of cold-water coral Lophelia pertusa in closed recirculating systems and climate change related short- and long-term experiments
Formulario de originalidad
The article submitted for review is original, has not been previously published and has not been simultaneously submitted for review in another journal.El artÃculo enviado a revisión es original, no ha sido publicado previamente y no se ha enviado simultáneamente para su evaluación en otra revist
Formulario de originalidad
The article submitted for review is original, has not been previously published and has not been simultaneously submitted for review in another journal.El artÃculo enviado a revisión es original, no ha sido publicado previamente y no se ha enviado simultáneamente para su evaluación en otra revist
Conservativeness of non-symmetric diffusion processes generated by perturbed divergence forms
Let E be an unbounded open (or closed) domain in Euclidean space of dimension
greater or equal to two. We present conservativeness criteria for (possibly
reflected) diffusions with state space E that are associated to fairly general
perturbed divergence form operators. Our main tool is a recently extended
forward and backward martingale decomposition, which reduces to the well-known
Lyons-Zheng decomposition in the symmetric case.Comment: Corrected typos, minor modification
Approximating L^2-signatures by their compact analogues
:Let G be a group together with an descending nested sequence of normal
subgroups G=G_0, G_1, G_2 G_3, ... of finite index [G:G_k] such the
intersection of the G_k-s is the trivial group. Let (X,Y) be a compact
4n-dimensional Poincare' pair and p: (\bar{X},\bar{Y}) \to (X,Y) be a
G-covering, i.e. normal covering with G as deck transformation group. We get
associated -coverings (X_k,Y_k) \to (X,Y). We prove that
sign^{(2)}(\bar{X},\bar{Y}) = lim_{k\to\infty} \frac{sign(X_k,Y_k)}{[G : G_k]},
where sign or sign^{(2)} is the signature or L^2-signature, respectively, and
the convergence of the right side for any such sequence (G_k)_k is part of the
statement
Maslov index, Lagrangians, Mapping Class Groups and TQFT
Given a mapping class f of an oriented surface Sigma and a lagrangian lambda
in the first homology of Sigma, we define an integer n_{lambda}(f). We use
n_{lambda}(f) (mod 4) to describe a universal central extension of the mapping
class group of Sigma as an index-four subgroup of the extension constructed
from the Maslov index of triples of lagrangian subspaces in the homology of the
surface. We give two descriptions of this subgroup. One is topological using
surgery, the other is homological and builds on work of Turaev and work of
Walker. Some applications to TQFT are discussed. They are based on the fact
that our construction allows one to precisely describe how the phase factors
that arise in the skein theory approach to TQFT-representations of the mapping
class group depend on the choice of a lagrangian on the surface.Comment: 31 pages, 11 Figures. to appear in Forum Mathematicu
Factor maps between tiling dynamical systems
We show that there is no Curtis-Hedlund-Lyndon Theorem for factor maps
between tiling dynamical systems: there are codes between such systems which
cannot be achieved by working within a finite window. By considering
1-dimensional tiling systems, which are the same as flows under functions on
subshifts with finite alphabets of symbols, we construct a `simple' code which
is not `local', a local code which is not simple, and a continuous code which
is neither local nor simple.Comment: 8 page
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