Isaac Vikram Chenchiah University of Bristol

Research: Vita Interests / Current Funding Preprints & Publications Organisation
Activities: Schools/Workshops Mini-Symposia Talks Visitors Teaching


Vita

  1. Lecturer in Applied Mathematics, School of Mathematics, University of Bristol (Since April 2006)
  2. Postdoctoral Associate, Max Planck Institute for Mathematics in the Sciences with Stefan Müller (January 2004 - March 2006)
  3. Ph.D., California Institute of Technology (January 2004)
    1. Ph.D. Thesis: Energy-minimizing microstructures in multiphase elastic solids
    2. Doctoral advisor: Kaushik Bhattacharya
  4. M.S., California Institute of Technology (June 1999)
  5. B.Tech., Indian Institute of Technology, Madras (July 1998)


Research interest: Mathematical problems in solid mechanics and materials science

  1. Mechanics of the growth of biological materials
  2. Molecular biomechanics
  3. Statics and dynamics of microstructures in solids
  4. Elasticity, phase transitions and damage in solids
  5. Applications of analysis especially non-convex calculus of variations and partial differential equations


Current research

(See also the sections on funding and preprints below.)
  1. Microstructure in multi-phase solids has long been a research interest of mine. Recently Anja Schloemerkemper and I have shown that Monoclinic-I martensite is capable of exhibiting T3 microstructures (which are infinite-rank laminates). Moreover we show that there is an open set of points for which this is possible. This is the first "real-world" example (we are aware of) of these theoretically much-investigated microstructures. As a consequence the lamination convex-hull of this material is strictly smaller than its quasiconvex-hull, again the first such "real-world" example.

    Along the way we also discovered that there are in fact two kinds of Monoclinic-I martensites, group-theoretically indistinguishable but with different convex polytope structures, and thus also different semi-convex hulls/envelopes. Curiously all known Monoclinic-I martensites lie in one of these groups. This work is part of a larger programme to understand the zero-energy states of monoclinic-I martensite and is funded by the Royal Society.

  2. Antoni Matyjaszkiewicz worked with Claire Grierson, Tanniemola Liverpool and I to understand plant uprooting. This three-month project was a part of his MRes in Complexity Sciences.

  3. Christopher Larsen and I have recently extended his earlier work with Adriana Garroni on damage from scalar to elastic materials capable of exhibiting multiple damage modes. This research was funded by the Leverhulme Trust.

  4. While I'm interested in several aspects of the mechanics of growth of biological materials I am currently focused on investigating continuum limits of discrete growing systems. Some preliminary results were presented at Banff in October 2010. For computational investigations I collaborate with Dariyash Kurenkeyeva who is supported by a Bolashak presidential scholarship. I've had many valuable discussions with Patrick Shipman on these and related matters. Pardeep Bahra joined me over summer for an undergraduate research project on this topic which was funded by the School of Mathematics.

  5. Jonathan Robbins and I are interested in vortex motion on Riemannian manifolds. Chiara Liverani joined us for four months this Spring.


Talks

(Past activities: Talks)
  1. 28 November 2011
    Surprises in monoclinic-I martensite
    Solid Mechanics and Materials Engineering Seminar, Department of Engineering Science, University of Oxford

  2. 4 January 2012
    Evolution of brittle damage with multiple damaged states
    Centre for Advanced Mathematical Sciences, American University of Beirut

  3. 23 March 2012
    PDE Seminar, Department of Mathematical Sciences, University of Bath


Visitors

(Past activities: Visitors)
  1. Pradeep Sharma, Department of Mechanical Engineering, University of Houston (Summer 2012)


Funding

  1. 2011
    ACCIS Innovation Seed Corn Funding
    Bi-stability: From nature to engineering
    (with Paul Weaver, Alberto Pirrera, Xavier Lachenal, Stephen Daynes, Advanced Composites Centre for Innovation and Science (ACCIS) and Department of Aerospace Engineering)

  2. 2010-11
    University of Bristol EPSRC Cross-Disciplinary Feasibility Account
    Engineering the substrate elasticity for stem cells differentiation in cartilage tissue: Experimental and mathematical modelling study
    (with Wael Kafienah, School of Cellular and Molecular Medicine and Sameer Rahatekar, Aerospace Engineering)

  3. 2010
    The Nuffield Foundation Undergraduate Research Bursary
    Analysis of asymmetric metric and inner product spaces
    (with Rosemary Drummond)

  4. 2009-12
    Royal Society International Joint Project
    Symmetrised rank-one convex hull of monoclinic martensite
    (with Anja Schloemerkemper, Institute for Mathematics, University of Würzburg)

    Formulas for Shapes, an article MaxPlanckResearch (the magazine of the Max Planck Society) by Peter Hergersberg has a non-technical introduction to the general area and this project.

  5. 2009-10
    Leverhulme Trust Visiting Professorship for Christopher Larsen, Department of Mathematical Sciences, Worcester Polytechnic Institute
    (with Valeriy Slastikov)


Preprints

  1. Non-laminate microstructures in monoclinic-I martensite (with Mathematica files)
    (with Anja Schloemerkemper)

  2. Cahn-Hilliard equations incorporating elasticity: Analysis and comparison to experiments
    (with Thomas Blesgen, available on request)

  3. Threshold-based quasi-static brittle damage evolution with multiple damaged elastic states
    (with Christopher Larsen, available on request)


Recent publications

  1. A generalised Cahn-Hilliard equation incorporating geometrically linear elasticity
    (with Thomas Blesgen)
    Interfaces and Free Boundaries, 13(1), 1-27, 2011

  2. Gradient flows in asymmetric metric spaces
    (with Marc Oliver Rieger and Johannes Zimmer)
    Nonlinear Analysis: Theory, Methods & Applications, 71(11), 5820-34, Dec. 2009
    MathSciNet review
    (Preprint)

  3. The relaxation of two-well energies with possibly unequal moduli
    (with Kaushik Bhattacharya)
    Archive for Rational Mechanics and Analysis, 187(3), 409-479, Mar. 2008
    MathSciNet review
    (Preprint)

  4. Examples of nonlinear homogenization in plane strain involving degenerate energies. I. Plane strain
    (with Kaushik Bhattacharya)
    Proceedings of the Royal Society A - Mathematical, Physical and Engineering Sciences, 461(2063), 3681 - 3703, Nov. 2005
    (Preprint)

  5. Towards the efficient computation of effective properties of microstructured materials
    (with Carl-Friedrich Kreiner and Johannes Zimmer)
    Comptes Rendus Mecanique, 332(3), 169-174, Mar. 2004
    (Preprint)


Organisation

  1. I am the applied mathematics representative for the university's Predictive Life Sciences research theme.
  2. I am involved with the Bristol Centre for Complexity Sciences and the Bristol Centre for Functional Nanomaterials.
  3. I was involved with Bridging the Gaps and am on the management committee of its successor.
  4. I am the Bristol representative on the organising committee of the South West Regional PDE Winter Schools (1, 2).


Teaching

Postgraduate Teaching (for Bristol Centre for Complexity Sciences)

  1. 2007-12: Nonlinear Dynamics (with Tanniemola Liverpool)

Undergraduate Teaching

  1. 2009-12: MATH M/36203 Applied Analysis (with Valeriy Slastikov)
  2. 2008-10: MATH 20901 Multivariable Calculus
  3. 2006-10: MATH 20900 Calculus 2

Postgraduate Projects (2010-11)

  1. Vortex motion on Riemannian manifolds (with Jonathan Robbins)
  2. Uprooting plants (with Claire Grierson and Tanniemola Liverpool)

Undergraduate Projects (2006-11)

  1. Analysis on asymmetric metric spaces
  2. Elasticity of helices (with Valeriy Slastikov)
  3. Geodesics on surfaces
  4. Hyperbolic geometry and hyperbolic convexity
  5. Isoperimetric problems
  6. Microstructure formation in martensitic solids
  7. Optimal transport systems
  8. Seismology


Research: Vita Interests / Current Funding Preprints & Publications Organisation
Activities: Schools/Workshops Mini-Symposia Talks Visitors Teaching
Email: Isaac.Chenchiah, Phone: +44 117 928 7984, Room 2.15
Updated: Friday 12 February 2012
University of Bristol