For a smooth projective variety
Fix a positive integer
 NSFPAR ID:
 10371268
 Publisher / Repository:
 Springer Science + Business Media
 Date Published:
 Journal Name:
 Mathematische Annalen
 Volume:
 387
 Issue:
 12
 ISSN:
 00255831
 Page Range / eLocation ID:
 p. 615687
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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Abstract X over an algebraic number fieldk a conjecture of Bloch and Beilinson predicts that the kernel of the Albanese map ofX is a torsion group. In this article we consider a product of smooth projective curves and show that if the conjecture is true for any subproduct of two curves, then it is true for$$X=C_1\times \cdots \times C_d$$ $X={C}_{1}\times \cdots \times {C}_{d}$X . For a product of two curves over$$X=C_1\times C_2$$ $X={C}_{1}\times {C}_{2}$ with positive genus we construct many nontrivial examples that satisfy the weaker property that the image of the natural map$$\mathbb {Q} $$ $Q$ is finite, where$$J_1(\mathbb {Q})\otimes J_2(\mathbb {Q})\xrightarrow {\varepsilon }{{\,\textrm{CH}\,}}_0(C_1\times C_2)$$ ${J}_{1}\left(Q\right)\otimes {J}_{2}\left(Q\right)\stackrel{\epsilon}{\to}{\phantom{\rule{0ex}{0ex}}\text{CH}\phantom{\rule{0ex}{0ex}}}_{0}({C}_{1}\times {C}_{2})$ is the Jacobian variety of$$J_i$$ ${J}_{i}$ . Our constructions include many new examples of nonisogenous pairs of elliptic curves$$C_i$$ ${C}_{i}$ with positive rank, including the first known examples of rank greater than 1. Combining these constructions with our previous result, we obtain infinitely many nontrivial products$$E_1, E_2$$ ${E}_{1},{E}_{2}$ for which the analogous map$$X=C_1\times \cdots \times C_d$$ $X={C}_{1}\times \cdots \times {C}_{d}$ has finite image.$$\varepsilon $$ $\epsilon $ 
Abstract We study the structure of the Liouville quantum gravity (LQG) surfaces that are cut out as one explores a conformal loopensemble
for$$\hbox {CLE}_{\kappa '}$$ ${\text{CLE}}_{{\kappa}^{\prime}}$ in (4, 8) that is drawn on an independent$$\kappa '$$ ${\kappa}^{\prime}$ LQG surface for$$\gamma $$ $\gamma $ . The results are similar in flavor to the ones from our companion paper dealing with$$\gamma ^2=16/\kappa '$$ ${\gamma}^{2}=16/{\kappa}^{\prime}$ for$$\hbox {CLE}_{\kappa }$$ ${\text{CLE}}_{\kappa}$ in (8/3, 4), where the loops of the CLE are disjoint and simple. In particular, we encode the combined structure of the LQG surface and the$$\kappa $$ $\kappa $ in terms of stable growthfragmentation trees or their variants, which also appear in the asymptotic study of peeling processes on decorated planar maps. This has consequences for questions that do a priori not involve LQG surfaces: In our paper entitled “$$\hbox {CLE}_{\kappa '}$$ ${\text{CLE}}_{{\kappa}^{\prime}}$CLE Percolations ” described the law of interfaces obtained when coloring the loops of a independently into two colors with respective probabilities$$\hbox {CLE}_{\kappa '}$$ ${\text{CLE}}_{{\kappa}^{\prime}}$p and . This description was complete up to one missing parameter$$1p$$ $1p$ . The results of the present paper about CLE on LQG allow us to determine its value in terms of$$\rho $$ $\rho $p and . It shows in particular that$$\kappa '$$ ${\kappa}^{\prime}$ and$$\hbox {CLE}_{\kappa '}$$ ${\text{CLE}}_{{\kappa}^{\prime}}$ are related via a continuum analog of the EdwardsSokal coupling between$$\hbox {CLE}_{16/\kappa '}$$ ${\text{CLE}}_{16/{\kappa}^{\prime}}$ percolation and the$$\hbox {FK}_q$$ ${\text{FK}}_{q}$q state Potts model (which makes sense even for nonintegerq between 1 and 4) if and only if . This provides further evidence for the longstanding belief that$$q=4\cos ^2(4\pi / \kappa ')$$ $q=4{cos}^{2}(4\pi /{\kappa}^{\prime})$ and$$\hbox {CLE}_{\kappa '}$$ ${\text{CLE}}_{{\kappa}^{\prime}}$ represent the scaling limits of$$\hbox {CLE}_{16/\kappa '}$$ ${\text{CLE}}_{16/{\kappa}^{\prime}}$ percolation and the$$\hbox {FK}_q$$ ${\text{FK}}_{q}$q Potts model whenq and are related in this way. Another consequence of the formula for$$\kappa '$$ ${\kappa}^{\prime}$ is the value of halfplane arm exponents for such divideandcolor models (a.k.a. fuzzy Potts models) that turn out to take a somewhat different form than the usual critical exponents for twodimensional models.$$\rho (p,\kappa ')$$ $\rho (p,{\kappa}^{\prime})$ 
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Abstract We study the distribution over measurement outcomes of noisy random quantum circuits in the regime of low fidelity, which corresponds to the setting where the computation experiences at least one gatelevel error with probability close to one. We model noise by adding a pair of weak, unital, singlequbit noise channels after each twoqubit gate, and we show that for typical random circuit instances, correlations between the noisy output distribution
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Abstract Let
denote the standard Haar system on [0, 1], indexed by$$(h_I)$$ $\left({h}_{I}\right)$ , the set of dyadic intervals and$$I\in \mathcal {D}$$ $I\in D$ denote the tensor product$$h_I\otimes h_J$$ ${h}_{I}\otimes {h}_{J}$ ,$$(s,t)\mapsto h_I(s) h_J(t)$$ $(s,t)\mapsto {h}_{I}\left(s\right){h}_{J}\left(t\right)$ . We consider a class of twoparameter function spaces which are completions of the linear span$$I,J\in \mathcal {D}$$ $I,J\in D$ of$$\mathcal {V}(\delta ^2)$$ $V\left({\delta}^{2}\right)$ ,$$h_I\otimes h_J$$ ${h}_{I}\otimes {h}_{J}$ . This class contains all the spaces of the form$$I,J\in \mathcal {D}$$ $I,J\in D$X (Y ), whereX andY are either the Lebesgue spaces or the Hardy spaces$$L^p[0,1]$$ ${L}^{p}[0,1]$ ,$$H^p[0,1]$$ ${H}^{p}[0,1]$ . We say that$$1\le p < \infty $$ $1\le p<\infty $ is a Haar multiplier if$$D:X(Y)\rightarrow X(Y)$$ $D:X\left(Y\right)\to X\left(Y\right)$ , where$$D(h_I\otimes h_J) = d_{I,J} h_I\otimes h_J$$ $D({h}_{I}\otimes {h}_{J})={d}_{I,J}{h}_{I}\otimes {h}_{J}$ , and ask which more elementary operators factor through$$d_{I,J}\in \mathbb {R}$$ ${d}_{I,J}\in R$D . A decisive role is played by theCapon projection given by$$\mathcal {C}:\mathcal {V}(\delta ^2)\rightarrow \mathcal {V}(\delta ^2)$$ $C:V\left({\delta}^{2}\right)\to V\left({\delta}^{2}\right)$ if$$\mathcal {C} h_I\otimes h_J = h_I\otimes h_J$$ $C{h}_{I}\otimes {h}_{J}={h}_{I}\otimes {h}_{J}$ , and$$I\le J$$ $\leftI\right\le \leftJ\right$ if$$\mathcal {C} h_I\otimes h_J = 0$$ $C{h}_{I}\otimes {h}_{J}=0$ , as our main result highlights: Given any bounded Haar multiplier$$I > J$$ $\leftI\right>\leftJ\right$ , there exist$$D:X(Y)\rightarrow X(Y)$$ $D:X\left(Y\right)\to X\left(Y\right)$ such that$$\lambda ,\mu \in \mathbb {R}$$ $\lambda ,\mu \in R$ i.e., for all$$\begin{aligned} \lambda \mathcal {C} + \mu ({{\,\textrm{Id}\,}}\mathcal {C})\text { approximately 1projectionally factors through }D, \end{aligned}$$ $\begin{array}{c}\lambda C+\mu (\phantom{\rule{0ex}{0ex}}\text{Id}\phantom{\rule{0ex}{0ex}}C)\phantom{\rule{0ex}{0ex}}\text{approximately 1projectionally factors through}\phantom{\rule{0ex}{0ex}}D,\end{array}$ , there exist bounded operators$$\eta > 0$$ $\eta >0$A ,B so thatAB is the identity operator ,$${{\,\textrm{Id}\,}}$$ $\phantom{\rule{0ex}{0ex}}\text{Id}\phantom{\rule{0ex}{0ex}}$ and$$\Vert A\Vert \cdot \Vert B\Vert = 1$$ $\Vert A\Vert \xb7\Vert B\Vert =1$ . Additionally, if$$\Vert \lambda \mathcal {C} + \mu ({{\,\textrm{Id}\,}}\mathcal {C})  ADB\Vert < \eta $$ $\Vert \lambda C+\mu (\phantom{\rule{0ex}{0ex}}\text{Id}\phantom{\rule{0ex}{0ex}}C)ADB\Vert <\eta $ is unbounded on$$\mathcal {C}$$ $C$X (Y ), then and then$$\lambda = \mu $$ $\lambda =\mu $ either factors through$${{\,\textrm{Id}\,}}$$ $\phantom{\rule{0ex}{0ex}}\text{Id}\phantom{\rule{0ex}{0ex}}$D or .$${{\,\textrm{Id}\,}}D$$ $\phantom{\rule{0ex}{0ex}}\text{Id}\phantom{\rule{0ex}{0ex}}D$