TY - CONF AB - Many daily activities present information in the form of a stream of text, and often people can benefit from additional information on the topic discussed. TV broadcast news can be treated as one such stream of text; in this paper we discuss finding news articles on the web that are relevant to news currently being broadcast.We evaluated a variety of algorithms for this problem, looking at the impact of inverse document frequency, stemming, compounds, history, and query length on the relevance and coverage of news articles returned in real time during a broadcast. We also evaluated several postprocessing techniques for improving the precision, including reranking using additional terms, reranking by document similarity, and filtering on document similarity. For the best algorithm, 84%-91% of the articles found were relevant, with at least 64% of the articles being on the exact topic of the broadcast. In addition, a relevant article was found for at least 70% of the topics. AU - Henzinger, Monika H AU - Chang, Bay-Wei AU - Milch, Brian AU - Brin, Sergey ID - 11860 SN - 978-158113680-7 T2 - Proceedings of the 12th international conference on World Wide Web TI - Query-free news search ER - TY - CONF AB - This article presents a high-level discussion of some problems that are unique to web search engines. The goal is to raise awareness and stimulate research in these areas. AU - Henzinger, Monika H AU - Motwani, Rajeev AU - Silverstein, Craig ID - 11909 SN - 1045-0823 T2 - 18th International Joint Conference on Artificial Intelligence TI - Challenges in web search engines ER - TY - JOUR AB - Among the major mathematical approaches to mirror symmetry are those of Batyrev-Borisov and Stromdnger-Yau-Zaslow (SYZ). The first is explicit and amenable to computation but is not clearly related to the physical motivation; the second is the opposite. Furthermore, it is far from obvious that mirror partners in one sense will also be mirror partners in the other. This paper concerns a class of examples that can be shown to satisfy the requirements of SYZ, but whose Hodge numbers are also equal. This provides significant evidence in support of SYZ. Moreover, the examples are of great interest in their own right: they are spaces of flat SLr-connections on a smooth curve. The mirror is the corresponding space for the Langlands dual group PGLr. These examples therefore throw a bridge from mirror symmetry to the duality theory of Lie groups and, more broadly, to the geometric Langlands program. AU - Tamas Hausel AU - Thaddeus, Michael ID - 1457 IS - 1 JF - Inventiones Mathematicae TI - Mirror symmetry, langlands duality, and the Hitchin system VL - 153 ER - TY - JOUR AB - The moduli space of stable bundles of rank $2$ and degree $1$ on a Riemann surface has rational cohomology generated by the so-called universal classes. The work of Baranovsky, King-Newstead, Siebert-Tian and Zagier provided a complete set of relations between these classes, expressed in terms of a recursion in the genus. This paper accomplishes the same thing for the noncompact moduli spaces of Higgs bundles, in the sense of Hitchin and Simpson. There are many more independent relations than for stable bundles, but in a sense the answer is simpler, since the formulas are completely explicit, not recursive. The results of Kirwan on equivariant cohomology for holomorphic circle actions are of key importance. AU - Tamas Hausel AU - Thaddeus, Michael ID - 1458 IS - 2 JF - Journal of the American Mathematical Society TI - Relations in the cohomology ring of the moduli space of rank 2 Higgs bundles VL - 16 ER - TY - JOUR AB - In this paper we explicitly calculate the analogue of the 't Hooft SU (2) Yang-Mills instantons on Gibbons-Hawking multi-centered gravitational instantons, which come in two parallel families: the multi-Eguchi-Hanson, or Ak ALE gravitational instantons and the multi-Taub-NUT spaces, or Ak ALF gravitational instantons. We calculate their energy and find the reducible ones. Following Kronheimer we also exploit the U(1) invariance of our solutions and study the corresponding explicit singular SU (2) magnetic monopole solutions of the Bogomolny equations on flat ℝ3. AU - Etesi, Gábor AU - Tamas Hausel ID - 1459 IS - 2 JF - Communications in Mathematical Physics TI - On Yang-Mills instantons over multi-centered gravitational instantons VL - 235 ER -