## 信息流

•   12-04 THE NEW YORKER 116

“It was a terrible kiss, shockingly bad; Margot had trouble believing that a grown man could possibly be so bad at kissing.”

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•   12-04 THE NEW YORKER 115

Françoise Mouly interviews the artist Tom Gauld about the inspiration behind “Holiday Track,” his illustration for the cover of the December 11, 2017, issue of The New Yorker.

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•   12-04 Hacker News 140

Titanic: Machine Learning from Disaster

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•   12-04 THE NEW YORKER 123

“The wild / declensions refuse to stay inside your wobbly brain.”

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•   12-04 Hacker News 120

The Trouble with Politicians Sharing Passwords

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•   12-04 THE NEW YORKER 135

Her essays emanated authority, but her fiction betrayed an aching sense of uncertainty.

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•   12-04 THE NEW YORKER 126

Webcasters promise transparency and objectivity, but not all views deserve equal time.

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•   12-02 Slashdot 147

An anonymous reader shares an NPR report: More than 90 percent of California's crop workers were born in Mexico. But in recent years, fewer have migrated to the U.S., according to the U.S. Department of Labor. Researchers point to a number of causes: tighter border controls; higher prices charged by smugglers; well-paying construction jobs and a growing middle-class in Mexico that doesn't want to pick vegetables for Americans. As a result, the average farmworker is now 45 years old, according to federal government data. Harvesting U.S. crops has been left to an aging population of farmworkers whose health has suffered from decades of hard labor. Older workers have a greater chance of getting injured and of developing chronic illnesses, which can raise the cost of workers' compensation and health insurance.

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•   12-02 MIT Technology 126

In this paper, we show that the non-symmetric convex polytope cannot be served as a window function to produce a Gabor orthonormal basis by any time-frequency sets.

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•   12-02 Ars Technica 126

Meanwhile, Leapforce has suddenly been acquired by competitor Appen.

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•   12-02 Ars Technica 119

Users will no longer be troubled by shady apps that hijack lock screens.

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•   12-02 Hacker News 125

App with local notification will crash iOS Springboard on Dec. 2

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•   12-02 Hacker News 127

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•   12-02 Ars Technica 120

After 37 years, Voyager has fired up its trajectory thrusters

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•   12-02 Ars Technica 132

This week, the scientists and engineers on the Voyager team did something very special.

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•   12-02 Slashdot 160

A memo from the Los Angeles office of the Immigration and Customs Enforcement bureau (ICE) says that the officials assess "with moderate confidence that Chinese-based company DJI Science and Technology is providing U.S. critical infrastructure and law enforcement data to the Chinese government." It also says that the information is based on "open source reporting and a reliable source within the unmanned aerial systems industry with first and secondhand access." Engadget reports: Part of the memo focuses on targets that the LA ICE office believes to be of interest to DJI. "DJI's criteria for selecting accounts to target appears to focus on the account holder's ability to disrupt critical infrastructure," it said. The memo goes on to say that DJI is particularly interested in infrastructure like railroads and utilities, companies that provide drinking water as well as weapon storage facilities. The LA ICE office concludes that it, "assesses with high confidence the critical infrastructu

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•   12-02 Quanta Magazine 138

Advances in number theory inspired by physics

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•   12-02 Ars Technica 138

AT&T: Your Internet service won't change after FCC eliminates net neutrality rules.

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•   12-02 MIT Technology 126

“Metalenses” created with photolithography could change the nature of imaging and optical processing.

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•   12-02 Ars Technica 123

Unnatural DNA used to encode unnatural proteins, all in otherwise normal cells.

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•   12-02 Slashdot 160

Not too long after Linus Torvalds wrote his own Unix kernel, which he called Linux, in the summer of 1991, a magazine was founded by enthusiasts to focus on the operating system. For more than two decades Linux Journal has been an authority magazine on all things Linux, often cited by mainstream outlets, but it is now shuttering doors. In a blog post, Linux Journal's Carlie Fairchild writes: It looks like we're at the end, folks. If all goes according to a plan we'd rather not have, the November issue of Linux Journal was our last. The simple fact is that we've run out of money, and options along with it. We never had a wealthy corporate parent or deep pockets of our own, and that made us an anomaly among publishers, from start to finish. While we got to be good at flying close to the ground for a long time, we lost what little elevation we had in November, when the scale finally tipped irrevocably to the negative. Thanks for all the fish.

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•   12-02 LWN 154

We were sad to encounter the announcement that Linux Journal will be shutting down. "The simple fact is that we’ve run out of money, and options along with it. We never had a wealthy corporate parent or deep pockets of our own, and that made us an anomaly among publishers, from start to finish. While we got to be good at flying close to the ground for a long time, we lost what little elevation we had in November, when the scale finally tipped irrevocably to the negative." Linux Journal was out there tracking what was happening in our community long before anybody else; it will be missed.

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•   12-02 Hacker News 131

Ask HN: Who is hiring? (December 2017)

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• Pulling off Xerox Parc's historical day of demos involved a borrowed airport refrigeration truck and an ax

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•   12-02 Slashdot 154

schwit1 shares a report from MIT Technology Review: Blockchain technology can eliminate the need for companies and other organizations to maintain centralized repositories of identifying information, and users can gain permanent control over who can access their data (hence "self-sovereign"), says Drummond Reed, chief trust officer at Evernym, a startup that's developing a blockchain network specifically for managing digital identities. Self-sovereign identity systems rely on public-key cryptography, the same kind that blockchain networks use to validate transactions. Although it's been around for decades, the technology has thus far proved difficult to implement for consumer applications. But the popularity of cryptocurrencies has inspired fresh commercial interest in making it more user-friendly. Public-key cryptography relies on pairs of keys, one public and one private, which are used to authenticate users and verify their encrypted transactions. Bitcoin users are represented on th

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•   12-02 Ars Technica 125

Following the Pharma Bro's conviction, prosecutors now want to seize his assets.

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•   12-02 Ars Technica 125

DOJ: We Want Martin Shkreli’s Enigma Machine, Wu-Tang Album, and $7.3M 收起 • AI analysis of cars in Street View images can accurately estimate income, race, education, and voting patterns 收起 • 12-02 THE NEW YORKER 124 Dept. of Zzzzs 收起 • 12-02 Ars Technica 115 In defending itself, Comcast falsely equates fast lanes with data cap exemptions. 收起 • 12-02 Ars Technica 120 Users with injected software are 15 percent more likely to experience crashes. 收起 • 12-02 Slashdot 139 hackingbear shares a report from Science Magazine: Results reported by a China-led space science mission provide a tantalizing hint -- but not firm evidence -- for dark matter. In its first 530 days of scientific observations, China's Dark Matter Particle Explorer (DAMPE) detected 1.5 million cosmic ray electrons and positrons above a certain energy threshold. When researchers plot of the number of particles against their energy, they saw hints of an anomalous break in the curve. Now, DAMPE has confirmed that deviation. "It may be evidence of dark matter," but the break in the curve "may be from some other cosmic ray source," says astrophysicist Chang Jin, who leads the collaboration at the Chinese Academy of Science's Purple Mountain Observatory in Nanjing. DAMPE's life span will be extended to 5 years given the excellent conditions of this Chinese spacecraft, then it can record over 10 billion cosmic events, allowing researchers to confirm if it is indeed dark matter. Perhaps more si 收起 • 12-02 Hacker News 127 Checklist for Python libraries APIs 收起 • 12-02 Ars Technica 127 Missteps on HTC Vive (literally and figuratively) are nothing compared to PSVR problems. 收起 • 12-02 Ars Technica 121 Trailer: Featuring interviews with Kraft, Liebergot, and other NASA pros who made it happen. 收起 • 12-02 Hacker News 118 Bucket Stream: Finding S3 Buckets by watching certificate transparency logs 收起 • This article demonstrates the electromagnetic simulation and optimization of a coaxial-microstrip transition for a material characterization measurement system, including the effect of the probes themselves, and an analysis of how surface roughness affects sensor performance. 收起 • 12-02 Hacker News 124 Borderline Personality Disorder: Treatment Resistance Reconsidered 收起 • 12-02 Slashdot 153 According to a PC Magazine report that uses data from Cellular Insights, the Qualcomm-powered iPhone X has better LTE performance than the Intel-powered model. From the report: There are three iPhone X models sold globally. Using lab equipment, Cellular Insights tested two of them: the Qualcomm-powered A1865, sold by Sprint, Verizon, and U.S. Cellular and in Australia, China, and India; and the Intel-powered A1901, sold by most other global carriers including AT&T and T-Mobile. (The third model, A1902, is only sold in Japan.) Here in the U.S., we anticipate that the SIM-free model sold directly by Apple will be the A1865, as that's the model that supports all four U.S. carriers. For this test, Cellular Insights looked at performance on LTE Band 4, which is used by every major U.S. carrier except Sprint, as well as in Canada and parts of Latin America. Cellular Insights attenuated an LTE signal from a strong -85dBm until the modems showed no performance. While both modems started ou 收起 • An anonymous reader quotes a report from Inverse: In the new paper, presented Thursday at the annual meeting of the Radiological Society of North America, a team of radiologists at Korea University report that smartphone addiction changes teenagers' brains. Using brain imaging, they argue that smartphone- and internet-addicted teenagers have imbalanced brain chemistry when compared to their peers who aren't addicted to smartphones or the internet. But scientists not involved with the study have some serious issues with their research. Perhaps the most important of these issues is the fact that "smartphone addiction" is not a scientifically established thing -- at least not yet. In the study, the team led by Dr. Hyung Suk Seo used "standardized internet and smartphone addiction tests to measure the severity of internet addiction" in nine boys and 10 girls, according to a statement. Then, they used MRS, a brain imaging technique that can identify particular brain chemicals, to examine th 收起 • 12-02 Slashdot 148 Well, now we know what paid for all those programmers cranking out the overhauled Firefox Quantum browser: a major infusion of new money. From a report: Mozilla, the nonprofit behind the open-source web browser, saw its 2016 revenue increase 24 percent to an all-time high of$520 million, it said Friday. Expenses grew too, but not as much, from $361 million to$337 million, so the organization's war chest is significantly bigger now. Mozilla, which now has about 1,200 employees, releases prior-year financial results in conjunction with tax filings. Most of Mozilla's money comes from partnerships with search engines like Google, Yahoo, DuckDuckGo, Baidu and Yandex. When you search through Firefox's address bar, those search engines show search ads alongside results and share a portion of the revenue to Mozilla. Mozilla in 2014 signed a major five-year deal with Yahoo to be the default search engine in the US, but canceled it only three years in and moved back to Google instead in Novemb

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•   12-02 THE NEW YORKER 131

Namesake Dept.

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• We consider maximal almost disjoint families of vector subspaces of countable vector spaces, focusing on questions of their size and definability. We prove that the minimum infinite cardinality of such a family cannot be decided in ZFC and that the "spectrum" of cardinalities of mad families of subspaces can be made arbitrarily large, in analogy to results for mad families on $\omega$. We apply the author's local Ramsey theory for vector spaces to give partial results concerning their definability.

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•   12-02 Hacker News 134

500 Startups still owes money to its latest group of startups

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•   12-02 MIT Technology 127

“Metalenses” created with photolithography could change the nature of imaging and optical processing.

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•   12-02 Hacker News 114

'Snoopers' charter' changes put forward

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•   12-02 Hacker News 113

Domogik: Take Control of Your Home

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•   12-02 Hacker News 113

My 20-Year Experience of Software Development Methodologies

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•   12-02 Slashdot 139

Even as more people than ever are tuning to Netflix, Hulu, Amazon Prime and other streaming services to look, piracy too continues to thrive, a research suggests. An anonymous reader shares a report: Intrigued by this interplay of legal and unauthorized viewing, researchers from Carnegie Mellon University and Universidade Catolica Portuguesa carried out an extensive study. They partnered with a major telco, which is not named, to analyze if BitTorrent downloading habits can be changed by offering legal alternatives. The researchers used a piracy-tracking firm to get a sample of thousands of BitTorrent pirates at the associated ISP. Half of them were offered a free 45-day subscription to a premium TV and movies package, allowing them to watch popular content on demand. To measure the effects of video-on-demand access on piracy, the researchers then monitored the legal viewing activity and BitTorrent transfers of the people who received the free offer, comparing it to a control group. Th

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•   12-02 Hacker News 110

The Never-Ending Foreclosure

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•   12-02 Ars Technica 114

"This is my Senator. He sold me out to telecom lobbyists."

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• We study Lipschitz, positively homogeneous and finite suprema preserving mappings defined on a max-cone of positive elements in a normed vector lattice. We prove that the lower spectral radius of such a mapping is always a minimum value of its approximate point spectrum. We apply this result to show that the spectral mapping theorem holds for the approximate point spectrum of such a mapping. By applying this spectral mapping theorem we obtain new inequalites for the Bonsall cone spectral radius of max type kernel operators.

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•   12-02 IEEE 128

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•   12-02 Hacker News 130

MacOS Update Accidentally Undoes Apple's “root” Bug Patch

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• View this webinar to learn how 3D printing’s versatility has paved the way for medical advancements by Cardiovascuar Systems, Inc. (CSI).

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• This paper is motivated by the interplay between the Tamari lattice, J.-L. Loday's realization of the associahedron, and J.-L. Loday and M. Ronco's Hopf algebra on binary trees. We show that these constructions extend in the world of acyclic $k$-triangulations, which were already considered as the vertices of V. Pilaud and F. Santos' brick polytopes. We describe combinatorially a natural surjection from the permutations to the acyclic $k$-triangulations. We show that the fibers of this surjection are the classes of the congruence $\equiv^k$ on $\mathfrak{S}_n$ defined as the transitive closure of the rewriting rule $U ac V_1 b_1 \cdots V_k b_k W \equiv^k U ca V_1 b_1 \cdots V_k b_k W$ for letters $a < b_1, \dots, b_k < c$ and words $U, V_1, \dots, V_k, W$ on $[n]$. We then show that the increasing flip order on $k$-triangulations is the lattice quotient of the weak order by this congruence. Moreover, we use this surjection to define a Hopf subalgebra of C. Malvenuto and C. Reuten

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• Providing a cut-free sequent calculus for S5 has a long history. The efforts in this direction are numerous, and each of them presents some difficulties. In this paper, we present a sequent calculus system for modal logic S5. It has in a sense subformula property. We show that the cut rule is admissible in this system.

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• We prove several classification results for $p$-Laplacian problems on bounded and unbounded domains, and deal with qualitative properties of sign-changing solutions to $p$-Laplacian equations on $\mathbb R^N$ involving critical nonlinearities. Moreover, on radial domains we characterise the compactness of possibly sign-changing Palais-Smale sequences.

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• In this note we prove that the Borel class of representations of 3-manifold groups to PGL(n,C) is preserved under Cartan involution up to sign. For representations to PGL(3,C) this is implied by a more general result of E. Falbel and Q. Wang, however our proof appears to be much shorter for that special case.

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• The axial anomaly of the massless free fermion is given by the index of the corresponding Dirac operator. We use the BV formalism and the methods of equivariant quantization of Costello and Gwilliam to produce a new, mathematical derivation of this result. We formalize through these methods the conventional wisdom that the anomaly measures the failure to construct a well-defined partition function.

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• We formulate a stochastic game of mean field type where the agents solve optimal stopping problems and interact through the proportion of players that have already stopped. Working with a continuum of agents, typical equilibria become functions of the common noise that all agents are exposed to, whereas idiosyncratic randomness can be eliminated by an Exact Law of Large Numbers. Under a structural monotonicity assumption, we can identify equilibria with solutions of a simple equation involving the distribution function of the idiosyncratic noise. Solvable examples allow us to gain insight into the uniqueness of equilibria and the dynamics in the population.

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• We consider the problem of finding confidence intervals for the risk of forecasting the future of a stationary, ergodic stochastic process, using a model estimated from the past of the process. We show that a bootstrap procedure provides valid confidence intervals for the risk, when the data source is sufficiently mixing, and the loss function and the estimator are suitably smooth. Autoregressive (AR(d)) models estimated by least squares obey the necessary regularity conditions, even when mis-specified, and simulations show that the finite- sample coverage of our bounds quickly converges to the theoretical, asymptotic level. As an intermediate step, we derive sufficient conditions for asymptotic independence between empirical distribution functions formed by splitting a realization of a stochastic process, of independent interest.

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• We show that, assuming Vojta's height conjecture, the height of a rational point on an algebraically hyperbolic variety can be bounded "uniformly" in families. This generalizes a result of Su-Ion Ih for curves of genus at least two to higher-dimensional varieties. As an application, we show that, assuming Vojta's height conjecture, the height of a rational point on a curve of general type is uniformly bounded. Finally, we prove a similar result for smooth hyperbolic surfaces with $c_1^2 > c_2$.

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•   12-01 MIT Technology 106

Many technologists think blockchains can revolutionize how we keep track of our identities.

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•   12-01 MIT Technology 114

The agency seeks a crackdown on companies offering kits to produce gene therapies for self-administration.

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• Let $X_1, \ldots, X_n$ be i.i.d. sample in $\mathbb{R}^p$ with zero mean and the covariance matrix $\mathbf{\Sigma}^*$. The classic principal component analysis estimates the projector $\mathbf{P}^*_{\mathcal{J}}$ onto the direct sum of some eigenspaces of $\mathbf{\Sigma}^*$ by its empirical counterpart $\widehat{\mathbf{P}}_{\mathcal{J}}$. Recent papers [Koltchinskii, Lounici, 2017], [Naumov et al., 2017] investigate the asymptotic distribution of the Frobenius distance between the projectors $\| \widehat{\mathbf{P}}_{\mathcal{J}} - \mathbf{P}^*_{\mathcal{J}} \|_2$. The problem arises when one tries to build a confidence set for the true projector effectively. We consider the problem from a Bayesian perspective and derive an approximation for the posterior distribution of the Frobenius distance between projectors. The derived theorems hold true for non-Gaussian data: the only assumption that we impose is the concentration of sample covariance $\widehat{\mathbf{\Sigma}}$ in a vicinity

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• Motivated by considerations of euclidean quantum gravity, we investigate a central question of spectral geometry, namely the question of reconstructability of compact Riemannian manifolds from the spectra of their Laplace operators. To this end, we study analytic paths of metrics that induce isospectral Laplace-Beltrami operators over oriented compact surfaces without boundary. Applying perturbation theory, we show that sets of conformally equivalent metrics on such surfaces contain no nontrivial convex subsets. This indicates that cases where the manifolds cannot be reconstructed from their spectra are highly constrained.

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• A linear operator $T$ between two lattice-normed locally solid Riesz spaces is said to be $p_\tau$-continuous if, for any $p_\tau$-null net $(x_\alpha)$, the net $(Tx_\alpha)$ is $p_\tau$-null, and $T$ is also said to be $p_\tau$-bounded operator if it sends $p_\tau$-bounded subsets to $p_\tau$-bounded subsets. They are generalize several known classes of operators such as continuous, order continuous, $p$-continuous, order bounded, $p$-bounded operators, etc. We also study $up_\tau$-continuous operators between lattice-normed locally solids Riesz spaces.

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• The notion of weakly monotone functions extends the classical definition of monotone function, that can be traced back to H.Lebesgue. It was introduced, in the setting of Sobolev spaces, by J.Manfredi, and thoroughly investigated in the more general framework of Orlicz-Sobolev spaces by diverse authors, including T.Iwaniec, J.Kauhanen, P.Koskela, J.Maly, J.Onninen, X.Zhong. The present paper complements and augments the available theory of pointwise regularity properties of weakly monotone functions in Orlicz-Sobolev spaces. In particular, a variant is proposed in a customary condition ensuring the continuity of functions from these spaces which avoids a technical additional assumption, and applies to certain situations when the latter is not fulfilled. The continuity outside sets of zero Orlicz capacity, and outside sets of (generalized) zero Hausdorff measure, will are also established when everywhere continuity fails.

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• The stability (or instability) of synchronization is important in a number of real world systems, including the power grid, the human brain and biological cells. For identical synchronization, the synchronizability of a network, which can be measured by the range of coupling strength that admits stable synchronization, can be optimized for a given number of nodes and links. Depending on the geometric degeneracy of the Laplacian eigenvectors, optimal networks can be classified into different sensitivity levels, which we define as a network's sensitivity index. We introduce an efficient and explicit way to construct optimal networks of arbitrary size over a wide range of sensitivity and link densities. Using coupled chaotic oscillators, we study synchronization dynamics on optimal networks, showing that cospectral optimal networks can have drastically different speed of synchronization. Such difference in dynamical stability is found to be closely related to the different structural sens

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• We present recent progress in theory of local conformal nets which is an operator algebraic approach to study chiral conformal field theory. We emphasize representation theoretic aspects and relations to theory of vertex operator algebras which gives a different and algebraic formulation of chiral conformal field theory.

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• We set up a correspondence between solutions of the Yang-Mills equations on ${\mathbb R}\times S^3$ and in Minkowski spacetime via de Sitter space. Some known Abelian and non-Abelian exact solutions are rederived. For the Maxwell case we present a straightforward algorithm to generate an infinite number of explicit solutions, with fields and potentials in Minkowski coordinates given by rational functions of increasing complexity. We illustrate our method with a nontrivial example.

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• Let $\Omega$ be a open bounded domain in $\mathbb{R}^n$ with smooth boundary $\partial\Omega$. We consider the equation $\Delta u + u^{\frac{n-k+2}{n-k-2}-\varepsilon} =0\,\hbox{ in }\,\Omega$, under zero Dirichlet boundary condition, where $\varepsilon$ is a small positive parameter. We assume that there is a $k$-dimensional closed, embedded minimal submanifold $K$ of $\partial\Omega$, which is non-degenerate, and along which a certain weighted average of sectional curvatures of $\partial\Omega$ is negative. Under these assumptions, we prove existence of a sequence $\varepsilon=\varepsilon_j$ and a solution $u_{\varepsilon}$ which concentrate along $K$, as $\varepsilon \to 0^+$, in the sense that $$|\nabla u_{\varepsilon} |^2\,\rightharpoonup \, S_{n-k}^{\frac{n-k}{2}} \,\delta_K \quad \mbox{as} \ \ \varepsilon \to 0$$ where $\delta_K$ stands for the Dirac measure supported on $K$ and $S_{n-k}$ is an explicit positive constant. This result generalizes the one obtained by del Pin

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• Weighted sums of left and right hand Kronecker products of Integer Sequence Doubly Affine (ISDA) as well as Generalized Arithmetic Progression Doubly Affine (GAPDA) arrays are used to generate larger ISDA arrays of multiplicative order (compound squares) from pairs of smaller ones. In two dimensions we find general expressions for the eigenvalues (EVs) and singular values (SVs) of the larger arrays in terms of the EVs and SVs of their constituent matrices, leading to a simple result for the rank of these highly singular compound matrices. Since the critical property of the smaller constituent matrices involves only identical row and column sums (often called semi-magic), the eigenvalue and singular value results can be applied to both magic squares and Latin squares. Additionally, the compounding process works in arbitrary dimensions due to the generality of the Kronecker product, providing a simple method to generate large order ISDA cubes and hypercubes. The first examples of compoun

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• Low-rank tensor approximations are plagued by a well-known problem - a tensor may fail to have a best rank-$r$ approximation. Over $\mathbb{R}$, it is known that such failures can occur with positive probability, sometimes with certainty. We will show that while such failures still occur over $\mathbb{C}$, they happen with zero probability. In fact we establish a more general result with useful implications on recent scientific and engineering applications that rely on sparse and/or low-rank approximations: Let $V$ be a complex vector space with a Hermitian inner product, and $X$ be a closed irreducible complex analytic variety in $V$. Given any complex analytic subvariety $Z \subseteq X$ with $\dim Z < \dim X$, we prove that a general $p \in V$ has a unique best $X$-approximation $\pi_X (p)$ that does not lie in $Z$. In particular, it implies that over $\mathbb{C}$, any tensor almost always has a unique best rank-$r$ approximation when $r$ is less than the generic rank. Our result

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• We investigate complete minimal submanifolds $f\colon M^3\to\Hy^n$ in hyperbolic space with index of relative nullity at least one at any point. The case when the ambient space is either the Euclidean space or the round sphere was already studied in \cite{dksv1} and \cite{dksv2}, respectively. If the scalar curvature is bounded from below we conclude that the submanifold has to be either totally geodesic or a generalized cone over a complete minimal surface lying in an equidistant submanifold of $\Hy^n$.

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• Why do natural and interesting sequences often turn out to be log-concave? We give one of many possible explanations, from the viewpoint of "standard conjectures". We illustrate with several examples from combinatorics.

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• A \$300 million telecom project will boost speeds or provide service to many for the first time

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•   12-01 arXiv 111

We present a general introduction to continued fractions, with special consideration to the function fields case. These notes were prepared for a summer class given this year in Beijing at Beihang university.

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• We use refined spectral sequence arguments to calculate known and previously unknown bi-Hamiltonian cohomology groups, which govern the deformation theory of semi-simple bi-Hamiltonian pencils of hydrodynamic type with one independent and $$N$$ dependent variables. In particular, we rederive the result of Dubrovin-Liu-Zhang that these deformations are parametrized by the so-called central invariants, which are $$N$$ smooth functions of one variable.

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