78 research outputs found
Acquisition of quantifier raising of a universal across an existential: Evidence from German
Our paper reports an act out task with German 5- and 6-year olds and adults involving doubly-quantified sentences with a universal object and an existential subject. We found that 5- and 6-year olds allow inverse scope in such sentences, while adults do not. Our findings contribute to a growing body of research (e.g. Gualmini et al. 2008; Musolino 2009, etc.) showing that children are more flexible in their scopal considerations than initially proposed by the Isomorphism proposal (Lidz & Musolino 2002; Musolino & Lidz 2006). This result provides support for a theory of German, a “no quantifier raising”-language, in terms of soft violable constraints, or global economy terms (Bobaljik & Wurmbrand 2012), rather than in terms of hard inviolable constraints or rules (Frey 1993). Finally, the results are compatible with Reinhart’s (2004) hypothesis that children do not perform global interface economy considerations due to the increased processing associated with it
Wall-crossing, open BPS counting and matrix models
We consider wall-crossing phenomena associated to the counting of D2-branes
attached to D4-branes wrapping lagrangian cycles in Calabi-Yau manifolds, both
from M-theory and matrix model perspective. Firstly, from M-theory viewpoint,
we review that open BPS generating functions in various chambers are given by a
restriction of the modulus square of the open topological string partition
functions. Secondly, we show that these BPS generating functions can be
identified with integrands of matrix models, which naturally arise in the free
fermion formulation of corresponding crystal models. A parameter specifying a
choice of an open BPS chamber has a natural, geometric interpretation in the
crystal model. These results extend previously known relations between open
topological string amplitudes and matrix models to include chamber dependence.Comment: 25 pages, 8 figures, published versio
Wall-crossing, free fermions and crystal melting
We describe wall-crossing for local, toric Calabi-Yau manifolds without
compact four-cycles, in terms of free fermions, vertex operators, and crystal
melting. Firstly, to each such manifold we associate two states in the free
fermion Hilbert space. The overlap of these states reproduces the BPS partition
function corresponding to the non-commutative Donaldson-Thomas invariants,
given by the modulus square of the topological string partition function.
Secondly, we introduce the wall-crossing operators which represent crossing the
walls of marginal stability associated to changes of the B-field through each
two-cycle in the manifold. BPS partition functions in non-trivial chambers are
given by the expectation values of these operators. Thirdly, we discuss crystal
interpretation of such correlators for this whole class of manifolds. We
describe evolution of these crystals upon a change of the moduli, and find
crystal interpretation of the flop transition and the DT/PT transition. The
crystals which we find generalize and unify various other Calabi-Yau crystal
models which appeared in literature in recent years.Comment: 61 pages, 14 figures, published versio
Multiple D4-D2-D0 on the Conifold and Wall-crossing with the Flop
We study the wall-crossing phenomena of D4-D2-D0 bound states with two units
of D4-brane charge on the resolved conifold. We identify the walls of marginal
stability and evaluate the discrete changes of the BPS indices by using the
Kontsevich-Soibelman wall-crossing formula. In particular, we find that the
field theories on D4-branes in two large radius limits are properly connected
by the wall-crossings involving the flop transition of the conifold. We also
find that in one of the large radius limits there are stable bound states of
two D4-D2-D0 fragments.Comment: 24 pages, 4 figures; v2: typos corrected, minor changes, a reference
adde
Wall-crossing of D4-D2-D0 and flop of the conifold
We discuss the wall-crossing of the BPS bound states of a non-compact
holomorphic D4-brane with D2 and D0-branes on the conifold. We use the
Kontsevich-Soibelman wall-crossing formula and analyze the BPS degeneracy in
various chambers. In particular we obtain a relation between BPS degeneracies
in two limiting attractor chambers related by a flop transition. Our result is
consistent with known results and predicts BPS degeneracies in all chambers.Comment: 15 pages, 4 figures; v2: typos corrected; v3: minor changes, a
reference added, version to be published in JHE
Wall Crossing, Quivers and Crystals
We study the spectrum of BPS D-branes on a Calabi-Yau manifold using the 0+1
dimensional quiver gauge theory that describes the dynamics of the branes at
low energies. The results of Kontsevich and Soibelman predict how the
degeneracies change. We argue that Seiberg dualities of the quiver gauge
theories, which change the basis of BPS states, correspond to crossing the
"walls of the second kind." There is a large class of examples, including local
del Pezzo surfaces, where the BPS degeneracies of quivers corresponding to one
D6 brane bound to arbitrary numbers of D4, D2 and D0 branes are counted by
melting crystal configurations. We show that the melting crystals that arise
are a discretization of the Calabi-Yau geometry. The shape of the crystal is
determined by the Calabi-Yau geometry and the background B-field, and its
microscopic structure by the quiver Q. We prove that the BPS degeneracies
computed from Q and Q' are related by the Kontsevich Soibelman formula, using a
geometric realization of the Seiberg duality in the crystal. We also show that,
in the limit of infinite B-field, the combinatorics of crystals arising from
the quivers becomes that of the topological vertex. We thus re-derive the
Gromov-Witten/Donaldson-Thomas correspondence
Statistical model and BPS D4-D2-D0 counting
We construct a statistical model that correctly reproduces the BPS partition
function of D4-D2-D0 bound states on the resolved conifold. We prove that the
known partition function of the BPS indices is reproduced by the counting
"triangular partitions" problem. The wall-crossing phenomena in our model are
also studied.Comment: 9 pages, 6 figures; v2: typos corrected, minor change
Quiver Structure of Heterotic Moduli
We analyse the vector bundle moduli arising from generic heterotic
compactifications from the point of view of quiver representations. Phenomena
such as stability walls, crossing between chambers of supersymmetry, splitting
of non-Abelian bundles and dynamic generation of D-terms are succinctly encoded
into finite quivers. By studying the Poincar\'e polynomial of the quiver moduli
space using the Reineke formula, we can learn about such useful concepts as
Donaldson-Thomas invariants, instanton transitions and supersymmetry breaking.Comment: 38 pages, 5 figures, 1 tabl
Evidence for Duality of Conifold from Fundamental String
We study the spectrum of BPS D5-D3-F1 states in type IIB theory, which are
proposed to be dual to D4-D2-D0 states on the resolved conifold in type IIA
theory. We evaluate the BPS partition functions for all values of the moduli
parameter in the type IIB side, and find them completely agree with the results
in the type IIA side which was obtained by using Kontsevich-Soibelman's
wall-crossing formula. Our result is a quite strong evidence for string
dualities on the conifold.Comment: 24 pages, 13 figures, v2: typos corrected, v3: explanations about
wall-crossing improved and figures adde
Quivers, YBE and 3-manifolds
We study 4d superconformal indices for a large class of N=1 superconformal
quiver gauge theories realized combinatorially as a bipartite graph or a set of
"zig-zag paths" on a two-dimensional torus T^2. An exchange of loops, which we
call a "double Yang-Baxter move", gives the Seiberg duality of the gauge
theory, and the invariance of the index under the duality is translated into
the Yang-Baxter-type equation of a spin system defined on a "Z-invariant"
lattice on T^2. When we compactify the gauge theory to 3d, Higgs the theory and
then compactify further to 2d, the superconformal index reduces to an integral
of quantum/classical dilogarithm functions. The saddle point of this integral
unexpectedly reproduces the hyperbolic volume of a hyperbolic 3-manifold. The
3-manifold is obtained by gluing hyperbolic ideal polyhedra in H^3, each of
which could be thought of as a 3d lift of the faces of the 2d bipartite
graph.The same quantity is also related with the thermodynamic limit of the BPS
partition function, or equivalently the genus 0 topological string partition
function, on a toric Calabi-Yau manifold dual to quiver gauge theories. We also
comment on brane realization of our theories. This paper is a companion to
another paper summarizing the results.Comment: 61 pages, 16 figures; v2: typos correcte
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