Finite groups | Discrete groups | Symmetry
In mathematics, physics and chemistry, a space group is the symmetry group of an object in space, usually in three dimensions. The elements of a space group (its symmetry operations) are the rigid transformations of an object that leave it unchanged. In three dimensions, space groups are classified into 219 distinct types, or 230 types if chiral copies are considered distinct. Space groups are discrete cocompact groups of isometries of an oriented Euclidean space in any number of dimensions. In dimensions other than 3, they are sometimes called . In crystallography, space groups are also called the crystallographic or Fedorov groups, and represent a description of the symmetry of the crystal. A definitive source regarding 3-dimensional space groups is the International Tables for Crystallography . (Wikipedia).
A01 An introduction to a series on space medicine
A new series on space medicine.
From playlist Space Medicine
The International Space Station continues an uninterrupted human presence in space as a test-bed for future exploration beyond low-Earth orbit and the only science lab in microgravity. This music video featuring the space station and its crews is set to the song "World" by recording artist
From playlist Real Space Stations - YouTube Space Lab with Liam & Brad
The Journey Continues for NASA's Human Space Exploration
The crew of STS-135, the final space shuttle mission, talks about the vibrancy of the International Space Station as a stepping stone for NASA's plans for future human exploration beyond low-Earth orbit.
From playlist What is Space? YouTube Space Lab with Liam and Brad
Interstellar flight: 10 Hard Facts
We can build powerful rockets able to carry people and machines into orbit, or even vault them to the moon. But our fastest spacecraft don't hold a candle to the distances that define Interstellar Flight. So what's on the drawing boards? What futuristic designs and fuel options promise to
From playlist Spaceten
What exactly is space? Brian Greene explains what the "stuff" around us is. Subscribe to our YouTube Channel for all the latest from World Science U. Visit our Website: http://www.worldscienceu.com/ Like us on Facebook: https://www.facebook.com/worldscienceu Follow us on Twitter: https:
From playlist Science Unplugged: Physics
Why the SpaceX NASA Mission is a Landmark For Astronaut Spaceflight
Not only is this the first time a commercial company is sending people into space, it is also the first crewed mission to the International Space Station to be launched from American soil in 9 years since the Space Shuttle was decommissioned. On the 27th of May SpaceX will make spaceflight
From playlist Space Videos - Domain of Science
Ask the Space Lab Expert: What is Space?
Have you ever wanted to go to Space? In this first episode of Space Lab, Brad and Liam from "World of the Orange" take you on an adventure to discover exactly what is Space. You'll find out about the solar system, the big bang, Sci-Fi movies that are becoming reality, and more!
From playlist What is Space? YouTube Space Lab with Liam and Brad
Every Space Shuttle ever launched, in order
NASA's pioneering reusable Space Transportation System (STS) was in operation for 30 years. 355 men and women flew on the five Space Shuttles over 135 missions. This video shows all of them. http://www.nature.com/spaceshuttle Soundtrack: 'PX3' and 'Retreat! Retreat!' by 65daysofstatic. *
From playlist My Top Videos
Sergio Zamora (1/20/23): The lower semi-continuity of \pi_1 and nilpotent structures in persistence
When a sequence of compact geodesic spaces X_i converges to a compact geodesic space X, under minimal assumptions there are surjective morphisms $\pi_1(X_i) \to \pi_1(X)$ for i large enough. In particular, a limit of simply connected spaces is simply connected. This is clearly not true for
From playlist Vietoris-Rips Seminar
Lie Groups and Lie Algebras: Lesson 41: Elementary Representation Theory I
Lie Groups and Lie Algebras: Lesson 41: Elementary Representation Theory I I wanted to begin a more intricate example of the principle of a Universal Covering group, but I think I need to cover a little background material. We need to get a grip on what is meant by "Representation Theory"
From playlist Lie Groups and Lie Algebras
Karen VOGTMANN - Spaces of Graphs, Tori and Other Flat Gamma-complexes
Spaces of finite graphs play a key role in perturbative quantum field theory, but also in many other areas of science and mathematics. Among these is geometric group theory, where they are used to model groups of automorphism of free groups. Graphs can be thought of as 1-dimensional flat m
From playlist Algebraic Structures in Perturbative Quantum Field Theory: a conference in honour of Dirk Kreimer's 60th birthday
Cornelia Drutu - Connections between hyperbolic geometry and median geometry
The interest of median geometry comes from its connections with property (T) and a-T-menability and, in its discrete version, with the solution to the virtual Haken conjecture. In this talk I shall explain how groups endowed with various forms of hyperbolic geometry, from lattices in rank
From playlist Geometry in non-positive curvature and Kähler groups
Karen Vogtmann - Outer space for right-angled Artin groups
Karen Vogtman (Cornell University, USA) Right-angled Artin groups interpolate between free groups and free abelian groups, so one may think of their outer automorphism groups as interpolating between Out(F_n) and GL(n,Z). I will describe an Outer space for these automorphism groups which
From playlist T1-2014 : Random walks and asymptopic geometry of groups.
Emily Stark: Action rigidity for free products of hyperbolic manifold groups
CIRM VIRTUAL EVENT Recorded during the meeting"Virtual Geometric Group Theory conference " the May 22, 2020 by the Centre International de Rencontres Mathématiques (Marseille, France) Filmmaker: Guillaume Hennenfent Find this video and other talks given by worldwide mathematicians on CIRM
From playlist Virtual Conference
Lie Groups and Lie Algebras: Lesson 38 - Preparation for the concept of a Universal Covering Group
Lie Groups and Lie Algebras: Lesson 38 - Preparation for the Universal Covering Group concept In this lesson we examine another amazing connection between the algebraic properties of the Lie groups with topological properties. We will lay the foundation to understand how discrete invaria
From playlist Lie Groups and Lie Algebras
Lie Groups and Lie Algebras: Lesson 22 - Lie Group Generators
Lie Groups and Lie Algebras: Lesson 22 - Lie Group Generators A Lie group can always be considered as a group of transformations because any group can transform itself! In this lecture we replace the "geometric space" with the Lie group itself to create a new collection of generators. P
From playlist Lie Groups and Lie Algebras
Alex Margolis: Quasi-actions and almost normal subgroups
CIRM VIRTUAL EVENT Recorded during the meeting"Virtual Geometric Group Theory conference " the May 27, 2020 by the Centre International de Rencontres Mathématiques (Marseille, France) Filmmaker: Guillaume Hennenfent Find this video and other talks given by worldwide mathematicians on CIRM
From playlist VIRTUAL EVENT GEOMETRIC GROUP THEORY CONFERENCE
Alex Margolis: Quasi-actions and almost normal subgroups
CIRM VIRTUAL EVENT Recorded during the meeting"Virtual Geometric Group Theory conference " the May 27, 2020 by the Centre International de Rencontres Mathématiques (Marseille, France) Filmmaker: Guillaume Hennenfent Find this video and other talks given by worldwide mathematicians on CIRM
From playlist Virtual Conference
SpaceX: Revolutionizing the Space Industry
SpaceX: Revolutionizing the Space Industry - SpaceX Explained Start learning for FREE today: https://brilliant.org/aperture Follow me!: https://www.instagram.com/mcewen/ / https://twitter.com/zynqas SpaceX is perhaps one of the most important companies in the world. When it comes to revol
From playlist Science & Technology 🚀