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BEGIN:VEVENT
DTSTART;TZID=America/New_York:20231211T103000
DTEND;TZID=America/New_York:20231211T113000
DTSTAMP:20260502T205737
CREATED:20240221T112820Z
LAST-MODIFIED:20240221T112900Z
UID:10002782-1702290600-1702294200@cmsa.fas.harvard.edu
SUMMARY:M-theory on nodal Calabi-Yau 3-folds and torsion refined GV-invariants
DESCRIPTION:Algebraic Geometry in String Theory Seminar \nSpeaker: Thorsten Schimannek (Utrecht University) \n\nTitle: M-theory on nodal Calabi-Yau 3-folds and torsion refined GV-invariants \nAbstract: The physics of M-theory and Type IIA strings on a projective nodal CY 3-folds is determined by the geometry of a small resolution\, even if the latter is not Kähler. We will demonstrate this explicitly in the context of a family of Calabi-Yau double covers of P^3. Using conifold transitions\, we prove that the exceptional curves in any small resolution are torsion while M-theory develops a discrete gauge symmetry.This leads to a torsion refinement of the ordinary Gopakumar-Vafa invariants\, that is associated to the singular Calabi-Yau and captures the enumerative geometry of the non-Kähler resolutions. We further argue that twisted circle compactifications of the 5d theory are dual to IIA compactifications on the nodal CY 3-fold with a flat but topologically non-trivial B-field. As a result\, the torsion refined invariants are encoded in the topological string partition functions with different choices for the global topology of a flat B-field. \nThe talk is based on 2108.09311\, 2212.08655 (with S. Katz\, A. Klemm\, and E. Sharpe) and 2307.00047 (with S. Katz).
URL:https://cmsa.fas.harvard.edu/event/agst-121123/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Algebraic Geometry in String Theory Seminar
ATTACH;FMTTYPE=image/jpeg:https://cmsa.fas.harvard.edu/media/CMSA-Algebraic-Geometry-in-String-Theory-12.11.2023-scaled.jpg
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20231127T103000
DTEND;TZID=America/New_York:20231127T113000
DTSTAMP:20260502T205737
CREATED:20240221T113319Z
LAST-MODIFIED:20240221T113411Z
UID:10002783-1701081000-1701084600@cmsa.fas.harvard.edu
SUMMARY:A p-adic Laplacian on the Tate curve
DESCRIPTION:Algebraic Geometry in String Theory Seminar \nSpeaker: An Huang (Brandeis) \nPre-talk Speaker: TBA: 10:00-10:30 am \n\n\nTitle: A p-adic Laplacian on the Tate curve \nAbstract: We shall first explain the relation between a family of deformations of genus zero p-adic string worldsheet action and Tate’s thesis. We then propose a genus one p-adic string worldsheet action. The key is the definition of a p-adic Laplacian operator on the Tate curve. We show that the genus one p-adic Green’s function exists\, is unique under some obvious constraints\, is locally constant off diagonal\, and has a reflection symmetry. It can also be numerically computed exactly off the diagonal\, thanks to some simplifications due to the p-adic setup. Numerics suggest that at least in some special cases\, the asymptotic behavior of the Green’s function near the diagonal is a direct p-adic counterpart of the familiar Archimedean case\, although the p-adic Laplacian is not a local operator. Joint work in progress with Rebecca Rohrlich.
URL:https://cmsa.fas.harvard.edu/event/agst-112723/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Algebraic Geometry in String Theory Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Algebraic-Geometry-in-String-Theory-11.27.2023.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20231023T103000
DTEND;TZID=America/New_York:20231023T113000
DTSTAMP:20260502T205737
CREATED:20240222T073026Z
LAST-MODIFIED:20240222T073026Z
UID:10002789-1698057000-1698060600@cmsa.fas.harvard.edu
SUMMARY:Gauged Linear Sigma Models and Cohomological Field Theories
DESCRIPTION:Algebraic Geometry in String Theory Seminar \n\nSpeaker: David Favero\, University of Minnesota \n\nTitle: Gauged Linear Sigma Models and Cohomological Field Theories \nAbstract: This talk is dedicated to the memory of my friend and collaborator Bumsig Kim and based on joint work with Ciocan-Fontanine-Guere-Kim-Shoemaker.  Gauged Linear Sigma Models (GLSMs)  serve as a means of interpolating between Kahler geometry and singularity theory.  In enumerative geometry\, they should specialize to both Gromov-Witten and Fan-Jarvis-Ruan-Witten theory.   In joint work with Bumsig Kim (see arXiv:2006.12182)\, we constructed such enumerative invariants for GLSMs.  Furthermore\, we proved that these invariants form a Cohomological Field Theory.   In this lecture\, I will describe GLSMs and Cohomological Field Theories\, review the history of their development in enumerative geometry\, and discuss the construction of these general invariants.  Briefly\, the invariants are obtained by forming the analogue of a virtual fundamental class which lives in the twisted Hodge complex over a certain “moduli space of maps to the GLSM”.  This virtual fundamental class roughly comes as the Atiyah class of a “virtual matrix factorization” associated to the GLSM data.
URL:https://cmsa.fas.harvard.edu/event/agst-102323/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Algebraic Geometry in String Theory Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Algebraic-Geometry-in-String-Theory-10.23.2023.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20231016T100000
DTEND;TZID=America/New_York:20231016T113000
DTSTAMP:20260502T205737
CREATED:20240222T075624Z
LAST-MODIFIED:20240222T075624Z
UID:10002790-1697450400-1697455800@cmsa.fas.harvard.edu
SUMMARY:Moduli of boundary polarized Calabi-Yau pairs
DESCRIPTION:Algebraic Geometry in String Theory Seminar \nPre-talk Speaker: Rosie Shen (Harvard): 10:00-10:30 am \nPre-talk Title: Introduction to the singularities of the MMP \n\nSpeaker: Dori Bejleri (Harvard Math & CMSA) \nTitle: Moduli of boundary polarized Calabi-Yau pairs \nAbstract: The theories of KSBA stability and K-stability furnish compact moduli spaces of general type pairs and Fano pairs respectively. However\, much less is known about the moduli theory of Calabi-Yau pairs. In this talk I will present an approach to constructing a moduli space of Calabi-Yau pairs which should interpolate between KSBA and K-stable moduli via wall-crossing.  I will explain how this approach can be used to construct projective moduli spaces of plane curve pairs. This is based on joint work with K. Ascher\, H. Blum\, K. DeVleming\, G. Inchiostro\, Y. Liu\, X. Wang. \n  \n 
URL:https://cmsa.fas.harvard.edu/event/agst-101623/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Algebraic Geometry in String Theory Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Algebraic-Geometry-in-String-Theory-10.16.2023.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20231002T103000
DTEND;TZID=America/New_York:20231002T113000
DTSTAMP:20260502T205737
CREATED:20240222T084421Z
LAST-MODIFIED:20240222T084421Z
UID:10002791-1696242600-1696246200@cmsa.fas.harvard.edu
SUMMARY:Motivic decomposition of moduli space from brane dynamics
DESCRIPTION:Algebraic Geometry in String Theory Seminar \n\n\nPre-talk Speaker: Kai Xu (CMSA): 10:00-10:30 am \n\nSpeaker: Kai Xu (CMSA) \nTitle: Motivic decomposition of moduli space from brane dynamics \nAbstract: Supersymmetric gauge theories encode deep structures in algebraic geometry\, and geometric engineering gives a powerful way to understand the underlying structures by string/M theory. In this talk we will see how the dynamics of M5 branes tell us about the motivic and semiorthogonal decompositions of moduli of bundles on curves.
URL:https://cmsa.fas.harvard.edu/event/agst-10223/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Algebraic Geometry in String Theory Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Algebraic-Geometry-in-String-Theory-10.02.2023.docx-1.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20230925T100000
DTEND;TZID=America/New_York:20230925T113000
DTSTAMP:20260502T205737
CREATED:20240222T090151Z
LAST-MODIFIED:20240222T090151Z
UID:10002792-1695636000-1695641400@cmsa.fas.harvard.edu
SUMMARY:Species Scale across String Moduli Spaces
DESCRIPTION:Algebraic Geometry in String Theory Seminar \n\nPre-talk Speaker: David Wu (Harvard Physics): 10:00-10:30 am \nSpeaker: Damian van de Heisteeg\, CMSA \n\nTitle: Species Scale across String Moduli Spaces \nAbstract: String theories feature a wide array of moduli spaces. We propose that the energy cutoff scale of these theories – the so-called species scale – can be determined through higher-curvature corrections. This species scale varies with the moduli; we use it both asymptotically to bound the diameter of the field space\, as well as in the interior to determine a “desert point” where it is maximized.
URL:https://cmsa.fas.harvard.edu/event/agst-92523/
LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States
CATEGORIES:Algebraic Geometry in String Theory Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20211123T093000
DTEND;TZID=America/New_York:20211123T103000
DTSTAMP:20260502T205737
CREATED:20240213T064610Z
LAST-MODIFIED:20240213T064610Z
UID:10002127-1637659800-1637663400@cmsa.fas.harvard.edu
SUMMARY:Wall crossing for moduli of stable log varieties
DESCRIPTION:
URL:https://cmsa.fas.harvard.edu/event/wall-crossing-for-moduli-of-stable-log-varieties/
LOCATION:MA
CATEGORIES:Algebraic Geometry in String Theory Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20211116T093000
DTEND;TZID=America/New_York:20211116T103000
DTSTAMP:20260502T205737
CREATED:20240214T051424Z
LAST-MODIFIED:20240304T061932Z
UID:10002537-1637055000-1637058600@cmsa.fas.harvard.edu
SUMMARY:Gromov-Witten theory of complete intersections
DESCRIPTION:Abstract: I will describe an inductive algorithm computing Gromov-Witten invariants in all genera with arbitrary insertions of all smooth complete intersections in projective space. The main idea is to show that invariants with insertions of primitive cohomology classes are controlled by their monodromy and by invariants defined without primitive insertions but with imposed nodes in the domain curve. To compute these nodal Gromov-Witten invariants\, we introduce the new notion of nodal relative Gromov-Witten invariants. This is joint work with Hülya Argüz\, Rahul Pandharipande\, and Dimitri Zvonkine (arxiv:2109.13323).
URL:https://cmsa.fas.harvard.edu/event/gromov-witten-theory-of-complete-intersections/
LOCATION:MA
CATEGORIES:Algebraic Geometry in String Theory Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Algebraic-Geometry-in-String-Theory-Seminar-11.16.21-1-1-1.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20211109T103000
DTEND;TZID=America/New_York:20211109T223000
DTSTAMP:20260502T205737
CREATED:20240304T062554Z
LAST-MODIFIED:20240304T062554Z
UID:10002897-1636453800-1636497000@cmsa.fas.harvard.edu
SUMMARY:Cosection localization for virtual fundamental classes of d-manifolds and Donaldson-Thomas invariants of Calabi-Yau fourfolds
DESCRIPTION:Speaker: Michail Savvas\, UT Austin \nTitle: Cosection localization for virtual fundamental classes of d-manifolds and Donaldson-Thomas invariants of Calabi-Yau fourfolds \nAbstract: Localization by cosection\, first introduced by Kiem-Li in 2010\, is one of the fundamental techniques used to study invariants in complex enumerative geometry. Donaldson-Thomas (DT) invariants counting sheaves on Calabi-Yau fourfolds were first defined by Borisov-Joyce in 2015 by combining derived algebraic and differential geometry.\nIn this talk\, we develop the theory of cosection localization for derived manifolds in the context of derived differential geometry of Joyce. As a consequence\, we also obtain cosection localization results for (-2)-shifted symplectic derived schemes. This provides a cosection localization formalism for the Borisov-Joyce DT invariant. As an immediate application\, the stable pair invariants of hyperkähler fourfolds\, constructed by Maulik-Cao-Toda\, vanish\, as expected. \n\n\n\nevent\n\n\nOrganizer: Seminars
URL:https://cmsa.fas.harvard.edu/event/11-9-21-cmsa-algebraic-geometry-in-string-theory-seminar/
LOCATION:MA
CATEGORIES:Algebraic Geometry in String Theory Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20211109T103000
DTEND;TZID=America/New_York:20211109T113000
DTSTAMP:20260502T205737
CREATED:20240213T062822Z
LAST-MODIFIED:20240304T062818Z
UID:10002112-1636453800-1636457400@cmsa.fas.harvard.edu
SUMMARY:Cosection localization for virtual fundamental classes of d-manifolds and Donaldson-Thomas invariants of Calabi-Yau fourfolds
DESCRIPTION:Abstract: Localization by cosection\, first introduced by Kiem-Li in 2010\, is one of the fundamental techniques used to study invariants in complex enumerative geometry. Donaldson-Thomas (DT) invariants counting sheaves on Calabi-Yau fourfolds were first defined by Borisov-Joyce in 2015 by combining derived algebraic and differential geometry.\nIn this talk\, we develop the theory of cosection localization for derived manifolds in the context of derived differential geometry of Joyce. As a consequence\, we also obtain cosection localization results for (-2)-shifted symplectic derived schemes. This provides a cosection localization formalism for the Borisov-Joyce DT invariant. As an immediate application\, the stable pair invariants of hyperkähler fourfolds\, constructed by Maulik-Cao-Toda\, vanish\, as expected.
URL:https://cmsa.fas.harvard.edu/event/cosection-localization-for-virtual-fundamental-classes-of-d-manifolds-and-donaldson-thomas-invariants-of-calabi-yau-fourfolds/
LOCATION:MA
CATEGORIES:Algebraic Geometry in String Theory Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Algebraic-Geometry-in-String-Theory-Seminar-11.09.21-1.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20211102T130000
DTEND;TZID=America/New_York:20211102T140000
DTSTAMP:20260502T205737
CREATED:20240214T052811Z
LAST-MODIFIED:20240304T062921Z
UID:10002538-1635858000-1635861600@cmsa.fas.harvard.edu
SUMMARY:Gauss-Manin connection in disguise: Quasi Jacobi forms of index zero
DESCRIPTION:Abstract: We consider the moduli space of abelian varieties with two marked points and a frame of the relative de Rham cohomology with boundary at these points compatible with its mixed Hodge structure. Such a moduli space gives a natural algebro-geometric framework for higher genus quasi Jacobi forms of index zero and their differential equations which are given as vector fields. In the case of elliptic curves we compute explicitly the Gauss-Manin connection and such vector fields. This is a joint work with J. Cao and R. Villaflor. (arXiv:2109.00587)
URL:https://cmsa.fas.harvard.edu/event/gauss-manin-connection-in-disguise-quasi-jacobi-forms-of-index-zero/
LOCATION:MA
CATEGORIES:Algebraic Geometry in String Theory Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20211026T130000
DTEND;TZID=America/New_York:20211026T140000
DTSTAMP:20260502T205737
CREATED:20240214T062643Z
LAST-MODIFIED:20240304T063155Z
UID:10002549-1635253200-1635256800@cmsa.fas.harvard.edu
SUMMARY:On singular Hilbert schemes of points
DESCRIPTION:Abstract: It is well known that the Hilbert schemes of points on smooth surfaces are smooth. In higher dimensions the Hilbert schemes of points are in general singular. In this talk we will present some examples and conjectures on the local structures of the Hilbert scheme of points on $\mathbb{P}^3$. As an application we study a conjecture of Wang-Zhou on the Euler characteristics of the tautological sheaves on Hilbert schemes of points.
URL:https://cmsa.fas.harvard.edu/event/on-singular-hilbert-schemes-of-points/
LOCATION:MA
CATEGORIES:Algebraic Geometry in String Theory Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20211019T130000
DTEND;TZID=America/New_York:20211019T140000
DTSTAMP:20260502T205737
CREATED:20240214T053044Z
LAST-MODIFIED:20240304T063307Z
UID:10002539-1634648400-1634652000@cmsa.fas.harvard.edu
SUMMARY:D-critical structure(s) on Quot schemes of points of Calabi-Yau 3-folds
DESCRIPTION:Abstract: D-critical schemes and Artin stacks were introduced by Joyce in 2015\, and play a central role in Donaldson-Thomas theory. They typically occur as truncations of (-1)-shifted symplectic derived schemes\, but the problem of constructing the d-critical structure on a “DT moduli space” without passing through derived geometry is wide open. We discuss this problem\, and new results in this direction\, when the moduli space is the Hilbert (or Quot) scheme of points on a Calabi-Yau 3-fold. Joint work with Michail Savvas.
URL:https://cmsa.fas.harvard.edu/event/d-critical-structures-on-quot-schemes-of-points-of-calabi-yau-3-folds/
LOCATION:MA
CATEGORIES:Algebraic Geometry in String Theory Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20211012T130000
DTEND;TZID=America/New_York:20211012T140000
DTSTAMP:20260502T205737
CREATED:20240214T053342Z
LAST-MODIFIED:20240304T063443Z
UID:10002540-1634043600-1634047200@cmsa.fas.harvard.edu
SUMMARY:Derived projectivizations of two-term complexes
DESCRIPTION:Abstract: For a given two-term complex of vector bundles on a derived scheme (or stack)\, there are three natural ways to define its “derived projectivizations”: (i) as the derived base-change of the classical projectivization of Grothendieck; (ii) as the derived moduli parametrizing one-dimensional locally free quotients; (iii) as the GIT quotient of the total space by $\mathbb{G}_m$-action. In this talk\, we first show that these three definitions are equivalent. Second\, we prove a structural theorem about the derived categories of derived projectivizations and study the corresponding mutation theory. Third\, we apply these results to various moduli situations\, including the moduli of certain stable pairs on curves and the Hecke correspondences of one-point modification of moduli of stable sheaves on surfaces. If time allowed\, we could also discuss the generalizations of these results to the derived Quot schemes of locally free quotients.
URL:https://cmsa.fas.harvard.edu/event/derived-projectivizations-of-two-term-complexes/
LOCATION:MA
CATEGORIES:Algebraic Geometry in String Theory Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20210928T130000
DTEND;TZID=America/New_York:20210928T140000
DTSTAMP:20260502T205737
CREATED:20240214T054256Z
LAST-MODIFIED:20240304T064006Z
UID:10002542-1632834000-1632837600@cmsa.fas.harvard.edu
SUMMARY:The Mirror Clemens-Schmid Sequence
DESCRIPTION:Abstract: I will present a four-term exact sequence relating the cohomology of a fibration to the cohomology of an open set obtained by removing the preimage of a general linear section of the base. This exact sequence respects three filtrations\, the Hodge\, weight\, and perverse Leray filtrations\, so that it is an exact sequence of mixed Hodge structures on the graded pieces of the perverse Leray filtration. I claim that this sequence should be thought of as a mirror to the Clemens-Schmid sequence describing the structure of a degeneration and formulate a “mirror P=W” conjecture relating the filtrations on each side. Finally\, I will present evidence for this conjecture coming from the K3 surface setting. This is joint work with Charles F. Doran.
URL:https://cmsa.fas.harvard.edu/event/the-mirror-clemens-schmid-sequence/
LOCATION:MA
CATEGORIES:Algebraic Geometry in String Theory Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20210921T130000
DTEND;TZID=America/New_York:20210921T140000
DTSTAMP:20260502T205737
CREATED:20240214T054755Z
LAST-MODIFIED:20240304T064114Z
UID:10002543-1632229200-1632232800@cmsa.fas.harvard.edu
SUMMARY:What do bounding chains look like\, and why are they related to linking numbers?
DESCRIPTION:Abstract: Gromov-Witten invariants count pseudo-holomorphic curves on a symplectic manifold passing through some fixed points and submanifolds. Similarly\, open Gromov-Witten invariants are supposed to count disks with boundary on a Lagrangian\, but in most cases such counts are not independent of some choices as we would wish. Motivated by Fukaya’11\, J. Solomon and S. Tukachinsky constructed open Gromov-Witten invariants in their 2016 papers from an algebraic perspective of $A_{\infty}$-algebras of differential forms\, utilizing the idea of bounding chains in Fukaya-Oh-Ohta-Ono’06. On the other hand\, Welschinger defined open invariants on sixfolds in 2012 that count multi-disks weighted by the linking numbers between their boundaries. We present a geometric translation of Solomon-Tukachinsky’s construction. From this geometric perspective\, their invariants readily reduce to Welschinger’s.
URL:https://cmsa.fas.harvard.edu/event/what-do-bounding-chains-look-like-and-why-are-they-related-to-linking-numbers/
LOCATION:MA
CATEGORIES:Algebraic Geometry in String Theory Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20210914T110200
DTEND;TZID=America/New_York:20210914T120200
DTSTAMP:20260502T205737
CREATED:20240214T055014Z
LAST-MODIFIED:20240304T064603Z
UID:10002544-1631617320-1631620920@cmsa.fas.harvard.edu
SUMMARY:Simplices in the Calabi–Yau web
DESCRIPTION:Abstract: Calabi–Yau manifolds of a given dimension are connected by an intricate web of birational maps. This web has deep consequences for the derived categories of coherent sheaves on such manifolds\, and for the associated string theories. In particular\, for 4-folds and beyond\, I will highlight certain simplices appearing in the web\, and identify corresponding derived category structures.
URL:https://cmsa.fas.harvard.edu/event/simplices-in-the-calabi-yau-web/
LOCATION:MA
CATEGORIES:Algebraic Geometry in String Theory Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20210907T093000
DTEND;TZID=America/New_York:20210907T103000
DTSTAMP:20260502T205737
CREATED:20240213T112149Z
LAST-MODIFIED:20240304T105626Z
UID:10002492-1631007000-1631010600@cmsa.fas.harvard.edu
SUMMARY:Derived categories of nodal quintic del Pezzo threefolds
DESCRIPTION:Abstract: Conifold transitions are important algebraic geometric constructions that have been of special interests in mirror symmetry\, transforming Calabi-Yau 3-folds between A- and B-models. In this talk\, I will discuss the change of the quintic del Pezzo 3-fold (Fano 3-fold of index 2 and degree 5) under the conifold transition at the level of the bounded derived category of coherent sheaves. The nodal quintic del Pezzo 3-fold X has at most 3 nodes. I will construct a semiorthogonal decomposition for D^b(X) and in the case of 1-nodal X\, detail the change of derived categories from its smoothing to its small resolution.
URL:https://cmsa.fas.harvard.edu/event/derived-categories-of-nodal-quintic-del-pezzo-threefolds/
LOCATION:MA
CATEGORIES:Algebraic Geometry in String Theory Seminar
END:VEVENT
END:VCALENDAR