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We introduce group actions on polyfolds and polyfold bundles. We prove quotient theorems for polyfolds, when the group action has finite isotropy. We prove that the sc-Fredholm property is preserved under quotient if the base poly...
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We introduce group actions on polyfolds and polyfold bundles. We prove quotient theorems for polyfolds, when the group action has finite isotropy. We prove that the sc-Fredholm property is preserved under quotient if the base polyfold is infinite dimensional. The quotient construction is the main technical tool in the construction of equivariant fundamental class in our future work. We also analyze the equivariant transversality near the fixed locus in the polyfold setting. In the case of S1-action with fixed locus, we give a sufficient condition for the existence of equivariant transverse perturbations. We outline the application to Hamiltonian-Floer cohomology and a proof of the weak Arnold conjecture for general symplectic manifolds, assuming the existence of Hamiltonian-Floer cohomology polyfolds.
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We consider exact fillings with vanishing first Chern class of asymptotically dynamically convex (ADC) manifolds. We construct two structure maps on the positive symplectic cohomology and prove that they are independent of the fil...
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We consider exact fillings with vanishing first Chern class of asymptotically dynamically convex (ADC) manifolds. We construct two structure maps on the positive symplectic cohomology and prove that they are independent of the filling for ADC manifolds. The invariance of the structure maps implies that the vanishing of symplectic cohomology and the existence of symplectic dilations are properties independent of the filling for ADC manifolds. Using them, various topological applications on symplectic fillings are obtained, including the uniqueness of diffeomorphism types of fillings for many contact manifolds. We use the structure maps to define the first symplectic obstructions to Weinstein fillability. In particular, we show that for all dimension 4k+3,k > 1, there exist infinitely many contact manifolds that are exactly fillable, almost Weinstein fillable but not Weinstein fillable. The invariance of the structure maps generalizes to strong fillings with vanishing first Chern class. We show that any strong filling with vanishing first Chern class of a class of manifolds, including (S2n-1,xi std), partial differential (T*LxCn) with L simply connected, must be exact and have unique diffeomorphism type. As an application of the proof, we show that the existence of symplectic dilation implies uniruledness. In particular, any affine exotic Cn with nonnegative log Kodaira dimension is a symplectic exotic Cn.
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We introduce the concept of k-(semi)-dilation for Liouville domains, which is a generalization of symplectic dilation defined by Seidel-Solomon. We prove that the existence of k-(semi)-dilation is a property independent of certain...
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We introduce the concept of k-(semi)-dilation for Liouville domains, which is a generalization of symplectic dilation defined by Seidel-Solomon. We prove that the existence of k-(semi)-dilation is a property independent of certain fillings for asymptotically dynamically convex (ADC) manifolds. We construct examples with k-dilations, but not k - 1-dilations for all k 0. We extract invariants taking value in N boolean OR {infinity} for Liouville domains and ADC contact manifolds, which are called the order of (semi)-dilation. The order of (semi) dilation serves as embedding and cobordism obstructions. We determine the order of (semi)-dilation for many Brieskorn varieties and use them to study cobordisms between Brieskorn manifolds.(c) 2022 Elsevier Inc. All rights reserved.
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We prove that (RP2n-1 ,xi(std)) is not exactly fillable for any n not equal 2(k) and there exist strongly fillable but not exactly fillable contact manifolds for all dimensions >= 5.
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Within the context of a transition economy, this article estimates how improved access to employment centers is capitalized into house price. We conduct an event study for the opening of subway Line 6 in Pudong district, Shanghai,...
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Within the context of a transition economy, this article estimates how improved access to employment centers is capitalized into house price. We conduct an event study for the opening of subway Line 6 in Pudong district, Shanghai, China. The new line significantly reduces the commuting time to major employment centers. Other things being equal, easier commutes to the central business district center result in an average house price appreciation of 3.75%, with the most distant residential zone enjoying the largest appreciation. When taking into account multiple employment centers, we find that the largest source of appreciation is from an improved access to a suburb center with poor initial accessibility and attractive job opportunities. Finally, the total appreciation caused by time savings to major employment centers decreases with neighborhood income level and increases with the distance from Line 6 stations.
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We show that the minimal symplectic area of Lagrangian submani-folds are universally bounded in symplectically aspherical domains with vanishing symplectic cohomology. If an exact domain admits a k-semi-dilation, then the minimal ...
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We show that the minimal symplectic area of Lagrangian submani-folds are universally bounded in symplectically aspherical domains with vanishing symplectic cohomology. If an exact domain admits a k-semi-dilation, then the minimal symplectic area is universally bounded for K (p, 1)-Lagrangians. As a corollary, we show that the Arnol'd chord conjecture holds for the following four cases: (1) Y admits an exact filling with SH*(W) = 0 (for some nonzero ring coefficient); (2) Y admits a symplectically aspherical filling with SH*(W) = 0 and simply connected Legendrians; (3) Y admits an exact filling with a k-semi-dilation and the Legendrian is a K(p, 1) space; (4) Y is the cosphere bundle S*Q with p(2)(Q) -> H-2(Q) non-trivial and the Legendrian has trivial p(2). In addition, we obtain the existence of homoclinic orbits in case (1). We also provide many more examples with k-semi-dilations in all dimensions = 4.
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We show that any symplectically aspherical/Calabi-Yau filling of Y := partial derivative(V x D) has vanishing symplectic cohomology for any Liouville domain V. In particular, we make no topological requirement on the filling and c...
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We show that any symplectically aspherical/Calabi-Yau filling of Y := partial derivative(V x D) has vanishing symplectic cohomology for any Liouville domain V. In particular, we make no topological requirement on the filling and c(1)(V) can be nonzero. Moreover, we show that for any symplectically aspherical/Calabi-Yau filling W of Y, the interior (W) over circle is diffeomorphic to the interior of V x D if pi(1)(Y) is abelian and dim V >= 4. And W is diffeomorphic to V x D if moreover the Whitehead group of pi(1)(Y) is trivial.
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Using data from the Chinese A-share market in 2004-12, we show how cognitive bias of individual analysts led to counterproductive effect in less-developed financial markets. We form an ex ante measure of analysts' expectation erro...
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Using data from the Chinese A-share market in 2004-12, we show how cognitive bias of individual analysts led to counterproductive effect in less-developed financial markets. We form an ex ante measure of analysts' expectation error, a measure suitable for markets with a short history. We find that star analysts tend to be more optimistic than ordinary analysts, and their biased opinions influence other analysts because of analyst herding behavior. Two-stage least square regression results suggest that consistent expectation errors among analysts can lead to earnings management. These insights are valuable to investors and regulators.
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This paper studies the interaction between housing market sentiment and government interventions. With a unique micro-level data from China, we construct a housing market sentiment index by applying the techniques in the finance l...
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This paper studies the interaction between housing market sentiment and government interventions. With a unique micro-level data from China, we construct a housing market sentiment index by applying the techniques in the finance literature. This index is significantly correlated with the confidence indexes from official sources. We find that housing market returns increase with contemporaneous sentiment, and high sentiment is followed by low returns. Tightening policies cannot reduce optimism, and high sentiment negatively impacts the effectiveness of tightening policies. This negative impact is especially significant in the zones where housing prices are sensitive to increasing sentiment. (C) 2018 Elsevier B.V. All rights reserved.
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With unique datasets, this paper studies the distributional impact of high-speed rail (HSR) on industrial developments by examining the house price premium of industrial parks in two important core-periphery city pairs of China: S...
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With unique datasets, this paper studies the distributional impact of high-speed rail (HSR) on industrial developments by examining the house price premium of industrial parks in two important core-periphery city pairs of China: Shanghai-Suzhou and Beijing-Langfang. We find that in core cities, the premium of service industrial parks (SIPs) has grown faster near HSR stations, while that of manufacturing industrial parks (MIPs) has grown slower near HSR stations. In periphery cities, however, the premium of SIPs has grown slower near HSR stations. Moreover, the premium of MIPs has grown faster near HSR stations of Suzhou. The results suggest that HSR facilitates a "spillover effect" between the core and peripheries for the manufacturing industry, but a "siphon effect" for the service industry. City-level GDP analysis for the two industries delivers consistent results. Our findings shed light on the underlying reason for the spatial variation in the economic impacts of HSR.
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