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We show that an infinite Galton–Watson tree, conditioned on its martingale limit being smaller than  $\varepsilon $ , agrees up to generation $K$ with a regular $\mu $ -ary tree, where $\mu $ is the essential minimum of the offspring distribution and the random variable $K$ is strongly concentrated near an explicit deterministic function growing like a multiple of $\log (1/\varepsilon )$ . More precisely, we show that if $\mu \ge 2$ then with high probability, as $\varepsilon \downarrow 0$ , $K$ takes exactly one or two values. This shows in particular that the conditioned trees converge to the regular $\mu $ -ary tree, providing an example of entropic repulsion where the limit has vanishing entropy. Our proofs are based on recent results on the left tail behaviour of the martingale limit obtained by Fleischmann and Wachtel [11].  相似文献   

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We prove the global well-posedness of the time-dependent Hartree–Fock–Bogoliubov (TDHFB) equations in \(\mathbb {R}^{1+1}\) with two-body interaction potential of the form \(N^{-1}v_N(x) = N^{\beta -1} v(N^\beta x)\) where \(v\ge 0\) is a sufficiently regular radial function, i.e., \(v \in L^1(\mathbb {R})\cap C^\infty (\mathbb {R})\). In particular, using methods of dispersive PDEs similar to the ones used in Grillakis and Machedon (Commun Partial Differ Equ 42:24–67, 2017), we are able to show for any scaling parameter \(\beta >0\) the TDHFB equations are globally well-posed in some Strichartz-type spaces independent of N, cf. (Bach et al. in The time-dependent Hartree–Fock–Bogoliubov equations for Bosons, 2016. arXiv:1602.05171).  相似文献   

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We present the main ideas and techniques of the proof that the duality-covariant four-dimensional non-commutative 4-model is renormalisable to all orders. This includes the reformulation as a dynamical matrix model, the solution of the free theory by orthogonal polynomials as well as the renormalisation byflow equations involving power-counting theorems for ribbon graphs drawn on Riemann surfaces  相似文献   

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We study frame properties of a matrix-valued wave packet system in the matrix-valued function space \(L^{2}(\mathbb {R}^{d}, \mathbb {C}^{s\times r})\), where the lower frame condition is controlled by a bounded linear operator \(\mathcal {K}\) on \(L^{2}(\mathbb {R}^{d}, \mathbb {C}^{s\times r})\) (lower \(\mathcal {K}\)-frame condition, in short). There are many differences between ordinary frames and \(\mathcal {K}\)-frames. The lower \(\mathcal {K}\)-frame condition for matrix-valued wave packet Bessel sequences in \(L^{2}(\mathbb {R}^{d},\mathbb {C}^{s\times r})\) in terms of operators; a trace functional associated with a bounded linear operator on \(L^{2}(\mathbb {R}^{d}, \mathbb {C}^{s\times r})\); and a series associated with a matrix-valued Bessel sequence is presented. It is shown that matrix-valued wave packet frames are stable under small perturbation with respect to wave packet window functions.  相似文献   

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In this paper we begin the study of the relationship between the local Gromov–Witten theory of Calabi–Yau rank two bundles over the projective line and the theory of integrable hierarchies. We first of all construct explicitly, in a large number of cases, the Hamiltonian dispersionless hierarchies that govern the full-descendent genus zero theory. Our main tool is the application of Dubrovin’s formalism, based on associativity equations, to the known results on the genus zero theory from local mirror symmetry and localization. The hierarchies we find are apparently new, with the exception of the resolved conifold in the equivariantly Calabi–Yau case. For this example the relevant dispersionless system turns out to be related to the long-wave limit of the Ablowitz–Ladik lattice. This identification provides us with a complete procedure to reconstruct the dispersive hierarchy which should conjecturally be related to the higher genus theory of the resolved conifold. We give a complete proof of this conjecture for genus g ≤ 1; our methods are based on establishing, analogously to the case of KdV, a “quasi-triviality” property for the Ablowitz–Ladik hierarchy at the leading order of the dispersive expansion. We furthermore provide compelling evidence in favour of the resolved conifold/Ablowitz–Ladik correspondence at higher genus by testing it successfully in the primary sector for g = 2.  相似文献   

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In this article, we study the vertexes $ \Xi_{Q}^{*}$ Q V and $ \Sigma_{Q}^{*}$ $ \Sigma_{Q}^{}$ V with the light-cone QCD sum rules, then assume the vector meson dominance of the intermediate $ \phi$ (1020) , $ \rho$ (770) and $ \omega$ (782) , and calculate the radiative decays $ \Xi_{Q}^{*}$ $ \rightarrow$ Q $ \gamma$ and $ \Sigma_{Q}^{*}$ $ \rightarrow$ $ \Sigma_{Q}^{}$ $ \gamma$ .  相似文献   

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In this paper, we first establish the regularity theorem for suitable weak solutions to the Ericksen–Leslie system in \({\mathbb{R}^2}\) . Building on such a regularity, we then establish the existence of a global weak solution to the Ericksen–Leslie system in \({\mathbb{R}^2}\) for any initial data in the energy space, under the physical constraints on the Leslie coefficients ensuring the dissipation of energy of the system, which is smooth away from at most finitely many times. This extends earlier works by Lin et al. (Arch Ration Mech Anal 197:297–336, 2010) on a simplified nematic liquid crystal flow to the general Ericksen–Leslie system.  相似文献   

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A direct entry and simple process for the synthesis of \(\upgamma \)-spiroiminolactones present in a large number of natural products has been developed. In the first step, the synthesis of parabanic acid derivatives was commenced from the reaction of \(\textit{N}{,}{} \textit{N}^{\prime }\)-disubstituted urea and thiourea with oxalyl chloride, then a three-component reaction was carried out with isocyanides, acetylenic esters, and \(\textit{N}{,}{} \textit{N}^{\prime }\)-disubstituted parabanic acid derivatives. The method allows the construction of a variety of \(\upgamma \)-spiroiminolactone structures in good to high yields starting from readily available precursors. It was found that in the case of \(\textit{N}{,}{} \textit{N}^{\prime }\)-diphenyl thioparabanic acid, additional products of \(\upgamma \)-dispiroiminolactones have been formed due to the higher electrophilicity of \(\upalpha \)-dicarbonyl groups. The structures were fully established using spectroscopic analysis NMR, IR, and Mass spectrometry. The crystal structure of \(\upgamma \)-dispiroiminolactone was confirmed from single-crystal X-ray diffraction study.  相似文献   

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We consider the blow-up problem for the nonlinear Schrödinger equation with quartic self-interacting potential on . We exhibit a class of initial data leading to the blow-up solutions which have at least two L 2-concentration points.  相似文献   

14.
An effective anisotropic t-J model for the pseudo-ladder compound CaCu2O3 is proposed based on recent experimental studies and band structure calculations. Superconducting pairing mediated by the exchange interaction in the model is investigated as a function of doping away from the antiferromagnetic insulating state. It is shown that strong anisotropy in the electronic spectrum suppresses superconducting temperature in comparison with conventional copper-oxide superconductors with square lattices.  相似文献   

15.
The hadronic decays η, ↦3π and ↦ηππ are investigated within the framework of U(3) chiral effective field theory in combination with a relativistic coupled-channels approach. Final state interactions are included by deriving s- and p-wave interaction kernels for meson-meson scattering from the chiral effective Lagrangian and iterating them in a Bethe-Salpeter equation. Very good overall agreement with currently available data on decay widths and spectral shapes is achieved.  相似文献   

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We study the possibility of phase transitions between Lifshitz black holes and other configurations by using free energies explicitly. A phase transition between Lifshitz soliton and Lifshitz black hole might not occur in three dimensions. We find that a phase transition between Lifshitz and BTZ black holes is unlikely to occur because they have different asymptotes. Similarly, we point out that any phase transition between Lifshitz and black branes is unlikely to occur in four dimensions since they have different asymptotes. This is consistent with the necessary condition for taking a phase transition in a gravitational system, which requires the same asymptote.  相似文献   

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We develop quantum mechanical Dirac ket-bra operator’s integration theory in $\mathfrak{Q}$ -ordering or $\mathfrak{P}$ -ordering to multimode case, where $\mathfrak{Q}$ -ordering means all Qs are to the left of all Ps and $\mathfrak{P}$ -ordering means all Ps are to the left of all Qs. As their applications, we derive $\mathfrak{Q}$ -ordered and $\mathfrak{P}$ -ordered expansion formulas of multimode exponential operator $e^{ - iP_l \Lambda _{lk} Q_k } $ . Application of the new formula in finding new general squeezing operators is demonstrated. The general exponential operator for coordinate representation transformation $\left| {\left. {\left( {_{q_2 }^{q_1 } } \right)} \right\rangle \to } \right|\left. {\left( {_{CD}^{AB} } \right)\left( {_{q_2 }^{q_1 } } \right)} \right\rangle $ is also derived. In this way, much more correpondence relations between classical coordinate transformations and their quantum mechanical images can be revealed.  相似文献   

19.
Vibrational spectrum of the ordered Pt(111)–( ?3 ×?3 ) \left( {\sqrt {3} \times \sqrt {3} } \right) R30°–K surface superstructure formed on the platinum surface with adsorption of 1/3 ML potassium is calculated with the use of the interatomic interaction potentials obtained in the strong bond approximation. Relaxation of the surface, dispersion of the surface phonons, local density of vibrational states, and polarization of phonon modes of adatoms and atoms of the substrate are discussed in the work. The theoretical results obtained agree well with the available experimental data.  相似文献   

20.
A series of diverse polyfunctionalized triheterocyclic benzothiazoles were easily prepared in excellent yields via the Biginelli reaction of 2-aminobenzothiazole with substituted benzaldehydes and $\upalpha $ -methylene ketones using $\hbox {FeF}_{3}$ as an expeditious catalyst under solvent-free conditions. The protocol provides a practical and straightforward approach toward highly functionalized triheterocyclic benzothiazole derivatives in excellent yields. The reaction was conveniently promoted by $\hbox {FeF}_{3}$ and the catalyst could be recovered easily after the reaction and reused without any loss of its catalytic activity. The advantageous features of this methodology are high atom economy, operational simplicity, shorter reaction time, convergence, and facile automation.  相似文献   

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