In mathematics, a perfect lattice (or perfect form) is a lattice in a Euclidean vector space, that is completely determined by the set S of its minimal vectors in the sense that there is only one positive definite quadratic form taking value 1 at all points of S. Perfect lattices were introduced by . A strongly perfect lattice is one whose minimal vectors form a spherical 4-design. This notion was introduced by . proved that a lattice is extreme if and only if it is both perfect and eutactic. The number of perfect lattices in dimensions 1, 2, 3, 4, 5, 6, 7, 8 is given by 1, 1, 1, 2, 3, 7, 33, 10916 (sequence in the OEIS). summarize the properties of perfect lattices of dimension up to 7. verified that the list of 10916 perfect lattices in dimension 8 found by Martinet and others is complete. It was proven by that only 2408 of these 10916 perfect lattices in dimension 8 are actually extreme lattices. (Wikipedia).
Lattice Structures in Ionic Solids
We've learned a lot about covalent compounds, but we haven't talked quite as much about ionic compounds in their solid state. These will adopt a highly ordered and repeating lattice structure, but the geometry of the lattice depends entirely on the types of ions and their ratio in the chem
From playlist General Chemistry
Gabriele NEBE - Lattices, Perfects lattices, Voronoi reduction theory, modular forms, ...
Lattices, Perfects lattices, Voronoi reduction theory, modular forms, computations of isometries and automorphisms The talks of Coulangeon will introduce the notion of perfect, eutactic and extreme lattices and the Voronoi's algorithm to enumerate perfect lattices (both Eulcidean and He
From playlist École d'Été 2022 - Cohomology Geometry and Explicit Number Theory
Lattice relations + Hermite normal form|Abstract Algebra Math Foundations 224 | NJ Wildberger
We introduce lattices and integral linear spans of vexels. These are remarkably flexible, common and useful algebraic objects, and they are the direct integral analogs of vector spaces. To understand the structure of a given lattice, the algorithm to compute a Hermite normal form basis is
From playlist Math Foundations
All crystalline materials have 3D, long range, periodic order. Therefore, they have a lattice which is a grid of repeating atomic positions. We can pick a small repeating area in this grid and it becomes a unit cell. The primitive unit cell should be the smallest repeatable unit cell.
From playlist Materials Sciences 101 - Introduction to Materials Science & Engineering 2020
Renaud COULANGEON - Lattices, Perfects lattices, Voronoi reduction theory, modular forms, ... 1
Lattices, Perfects lattices, Voronoi reduction theory, modular forms, computations of isometries and automorphisms The talks of Coulangeon will introduce the notion of perfect, eutactic and extreme lattices and the Voronoi's algorithm to enumerate perfect lattices (both Eulcidean and He
From playlist École d'Été 2022 - Cohomology Geometry and Explicit Number Theory
Renaud COULANGEON - Lattices, Perfects lattices, Voronoi reduction theory, modular forms, ... 2
The talks of Coulangeon will introduce the notion of perfect, eutactic and extreme lattices and the Voronoi's algorithm to enumerate perfect lattices (both Eulcidean and Hermitian). The talk of Nebe will build upon these notions, introduce Boris Venkov's notion of strongly perfect lattic
From playlist École d'Été 2022 - Cohomology Geometry and Explicit Number Theory
Mod-01 Lec-5ex Diffraction Methods For Crystal Structures - Worked Examples
Condensed Matter Physics by Prof. G. Rangarajan, Department of Physics, IIT Madras. For more details on NPTEL visit http://nptel.iitm.ac.in
From playlist NPTEL: Condensed Matter Physics - CosmoLearning.com Physics Course
This video introduces lattice paths and explains how to determine the shortest lattice path.
From playlist Counting (Discrete Math)
How to construct the Leech lattice
This lecture describes an astonishingly simple construction of the Leech lattice in 24 dimensions, found by John Conway and Neal Sloane. This is an experimental joint video with @Lyam Boylan (https://www.tiktok.com/@yamsox/video/7057530890381053189) who added the animation, the thumbnai
From playlist Math talks
Quadratic forms and Hermite constant, reduction theory by Radhika Ganapathy
Discussion Meeting Sphere Packing ORGANIZERS: Mahesh Kakde and E.K. Narayanan DATE: 31 October 2019 to 06 November 2019 VENUE: Madhava Lecture Hall, ICTS Bangalore Sphere packing is a centuries-old problem in geometry, with many connections to other branches of mathematics (number the
From playlist Sphere Packing - 2019
Monomer Percolation by Kedar Damle
PROGRAM FRUSTRATED METALS AND INSULATORS (HYBRID) ORGANIZERS Federico Becca (University of Trieste, Italy), Subhro Bhattacharjee (ICTS-TIFR, India), Yasir Iqbal (IIT Madras, India), Bella Lake (Helmholtz-Zentrum Berlin für Materialien und Energie, Germany), Yogesh Singh (IISER Mohali, In
From playlist FRUSTRATED METALS AND INSULATORS (HYBRID, 2022)
Semidefinte programming bounds by Abhinav Kumar
DISCUSSION MEETING SPHERE PACKING ORGANIZERS: Mahesh Kakde and E.K. Narayanan DATE: 31 October 2019 to 06 November 2019 VENUE: Madhava Lecture Hall, ICTS Bangalore Sphere packing is a centuries-old problem in geometry, with many connections to other branches of mathematics (number the
From playlist Sphere Packing - 2019
Student Video: 2D Brillouin Zones
MIT RES.3-004 Visualizing Materials Science, Fall 2017 Speaker: Jurgis Ruza View the complete course: https://ocw.mit.edu/RES-3-004F17 YouTube Playlist: https://www.youtube.com/playlist?list=PLUl4u3cNGP62EJXwSgoVRfh1tEiSc01bh A short introduction into reciprocal space and the construction
From playlist MIT RES.3-004 Visualizing Materials Science, Fall 2017
Mark W. McConnell: Computing Hecke operators for cohomology of arithmetic subgroups of SL_n(Z)
Abstract: We will describe two projects. The first which is joint with Avner Ash and Paul Gunnells, concerns arithmetic subgroups Γ of G=SL_4(Z). We compute the cohomology of Γ∖G/K, focusing on the cuspidal degree H^5. We compute a range of Hecke operators on this cohomology. We fi Galois
From playlist Number Theory
Mod-01 Lec-39 Defects in Solids - Line and Surface Defects
Condensed Matter Physics by Prof. G. Rangarajan, Department of Physics, IIT Madras. For more details on NPTEL visit http://nptel.iitm.ac.in
From playlist NPTEL: Condensed Matter Physics - CosmoLearning.com Physics Course
Thermalization in Classical Lattices by Hong Zhao
PROGRAM CLASSICAL AND QUANTUM TRANSPORT PROCESSES : CURRENT STATE AND FUTURE DIRECTIONS (ONLINE) ORGANIZERS: Alberto Imparato (University of Aarhus, Denmark), Anupam Kundu (ICTS-TIFR, India), Carlos Mejia-Monasterio (Technical University of Madrid, Spain) and Lamberto Rondoni (Polytechn
From playlist Classical and Quantum Transport Processes : Current State and Future Directions (ONLINE)2022
Introduction to sets || Set theory Overview - Part 1
A set is the mathematical model for a collection of different things; a set contains elements or members, which can be mathematical objects of any kind: numbers, symbols, points in space, lines, other geometrical shapes, variables, or even other #sets. The #set with no element is the empty
From playlist Set Theory