Homochirality is a uniformity of chirality, or handedness. Objects are chiral when they cannot be superposed on their mirror images. For example, the left and right hands of a human are approximately mirror images of each other but are not their own mirror images, so they are chiral. In biology, 19 of the 20 natural amino acids are homochiral, being L-chiral (left-handed), while sugars are D-chiral (right-handed). Homochirality can also refer to enantiopure substances in which all the constituents are the same enantiomer (a right-handed or left-handed version of an atom or molecule), but some sources discourage this use of the term. It is unclear whether homochirality has a purpose; however, it appears to be a form of information storage. One suggestion is that it reduces entropy barriers in the formation of large organized molecules. It has been experimentally verified that amino acids form large aggregates in larger abundance from an enantiopure samples of the amino acid than from racemic (enantiomerically mixed) ones. It is not clear whether homochirality emerged before or after life, and many mechanisms for its origin have been proposed. Some of these models propose three distinct steps: mirror-symmetry breaking creates a minute enantiomeric imbalance, chiral amplification builds on this imbalance, and chiral transmission is the transfer of chirality from one set of molecules to another. (Wikipedia).
Homomorphisms in abstract algebra
In this video we add some more definition to our toolbox before we go any further in our study into group theory and abstract algebra. The definition at hand is the homomorphism. A homomorphism is a function that maps the elements for one group to another whilst maintaining their structu
From playlist Abstract algebra
Group Homomorphisms - Abstract Algebra
A group homomorphism is a function between two groups that identifies similarities between them. This essential tool in abstract algebra lets you find two groups which are identical (but may not appear to be), only similar, or completely different from one another. Homomorphisms will be
From playlist Abstract Algebra
Introduction to Homotopy Theory- PART 1: UNIVERSAL CONSTRUCTIONS
The goal of this series is to develop homotopy theory from a categorical perspective, alongside the theory of model categories. We do this with the hope of eventually developing stable homotopy theory, a personal goal a passion of mine. I'm going to follow nLab's notes, but I hope to add t
From playlist Introduction to Homotopy Theory
Homotopy type theory: working invariantly in homotopy theory -Guillaume Brunerie
Short talks by postdoctoral members Topic: Homotopy type theory: working invariantly in homotopy theory Speaker: Guillaume Brunerie Affiliation: Member, School of Mathematics Date: September 26, 2017 For more videos, please visit http://video.ias.edu
From playlist Mathematics
Homomorphisms (Abstract Algebra)
A homomorphism is a function between two groups. It's a way to compare two groups for structural similarities. Homomorphisms are a powerful tool for studying and cataloging groups. Be sure to subscribe so you don't miss new lessons from Socratica: http://bit.ly/1ixuu9W ♦♦♦♦♦♦♦♦♦♦ W
From playlist Abstract Algebra
Homotopy Group - (1)Dan Licata, (2)Guillaume Brunerie, (3)Peter Lumsdaine
(1)Carnegie Mellon Univ.; Member, School of Math, (2)School of Math., IAS, (3)Dalhousie Univ.; Member, School of Math April 11, 2013 In this general survey talk, we will describe an approach to doing homotopy theory within Univalent Foundations. Whereas classical homotopy theory may be des
From playlist Mathematics
Homophily Solution - Intro to Algorithms
This video is part of an online course, Intro to Algorithms. Check out the course here: https://www.udacity.com/course/cs215.
From playlist Introduction to Algorithms
Debunking James Tour’s Latest Pathetic Series (Part 3 of 4)
James Tour is back at it again, folks! He didn't like my response to his ridiculous series on abiogenesis, exposing him as a complete fraud with no clue what he's talking about on this topic. After some time off to lick his wounds, he's returned with another hot pile of stylized garbage, w
From playlist Debunks/Discussions/Debates
Homochirality: Why Nature Never Makes Mirror Molecules
The first 500 people to use this link will get 2 free months of Skillshare Premium Membership: https://skl.sh/stevemould10 Molecules of biological origin always have a fixed handedness or chirality. For example you only ever see right handed sugars and left handed amino acids in nature. B
From playlist Chemistry
Response to James Tour: 700 Papers and Still Clueless (Part 1 of 2)
Last year I made a video about James Tour, a chemist and creationist who speaks out against origin of life research. He didn't like it much, so he decided to make a 14-part series about how dumb I am. He really pulled out all the stops, parading all of his classic fallacious talking points
From playlist Debunks/Discussions/Debates
Synthesis Workshop: Demystifying the Soai Reaction with Dr. Soumitra Athavale (Episode 47)
In this Research Spotlight episode, we are joined by Dr. Soumitra Athavale, who takes us through his work on the Soai reaction. Parent reference: Athavale, S. V.; Simon, A.; Houk, K. N.; Denmark, S. E.; Nat. Chem. 2020, 12 , 412-423. Other references (in order of appearance): For a mast
From playlist Special Topics: Organometallics
Homomorphisms in abstract algebra examples
Yesterday we took a look at the definition of a homomorphism. In today's lecture I want to show you a couple of example of homomorphisms. One example gives us a group, but I take the time to prove that it is a group just to remind ourselves of the properties of a group. In this video th
From playlist Abstract algebra
Homotopy elements in the homotopy group π₂(S²) ≅ ℤ. Roman Gassmann and Tabea Méndez suggested some improvements to my original ideas.
From playlist Algebraic Topology
Chiral molecules from outer space
First mirror image molecule spotted in interstellar space. Read more: http://scim.ag/1UsLb6i Read the paper: http://scim.ag/1YpPj8Q
From playlist Materials and technology
Episode 1/13: Introduction to Abiogenesis // A Course on Abiogenesis by Dr. James Tour
In this introductory episode, Dr. James Tour builds the foundation for this series, defining abiogenesis and describing the characteristics for life, including a discussion on early Earth's conditions and challenges for prebiotic chemistry. After reviewing the four classes of molecules nee
From playlist Java Programming
Response to James Tour: 700 Papers and Still Clueless (Part 2 of 2)
Last year I made a video about James Tour, a chemist and creationist who speaks out against origin of life research. He didn't like it much, so he decided to make a 14-part series about how dumb I am. He really pulled out all the stops, parading all of his classic fallacious talking points
From playlist Debunks/Discussions/Debates
The Delicious Unraveling of James Tour
James Tour is back at it, folks! He didn't like the humiliation I served him in debunking to smithereens his propaganda series against origin of life research, so after a year or so of licking his wounds, he's back with some more content. And if you were hoping that he has become even more
From playlist Debunks/Discussions/Debates
Debunking James Tour’s Latest Pathetic Series (Part 4 of 4)
James Tour is back at it again, folks! He didn't like my response to his ridiculous series on abiogenesis, exposing him as a complete fraud with no clue what he's talking about on this topic. After some time off to lick his wounds, he's returned with another hot pile of stylized garbage, w
From playlist Debunks/Discussions/Debates
Debunking James Tour’s Latest Pathetic Series (Part 1 of 4)
James Tour is back at it again, folks! He didn't like my response to his ridiculous series on abiogenesis, exposing him as a complete fraud with no clue what he's talking about on this topic. After some time off to lick his wounds, he's returned with another hot pile of stylized garbage, w
From playlist Debunks/Discussions/Debates
Homophily - Intro to Algorithms
This video is part of an online course, Intro to Algorithms. Check out the course here: https://www.udacity.com/course/cs215.
From playlist Introduction to Algorithms