In order theory, a subset A of a partially ordered set P is a strong downwards antichain if it is an antichain in which no two distinct elements have a common lower bound in P, that is, In the case where P is ordered by inclusion, and closed under subsets, but does not contain the empty set, this is simply a family of pairwise disjoint sets. A strong upwards antichain B is a subset of P in which no two distinct elements have a common upper bound in P. Authors will often omit the "upwards" and "downwards" term and merely refer to strong antichains. Unfortunately, there is no common convention as to which version is called a strong antichain. In the context of forcing, authors will sometimes also omit the "strong" term and merely refer to antichains. To resolve ambiguities in this case, the weaker type of antichain is called a weak antichain. If (P, ≤) is a partial order and there exist distinct x, y ∈ P such that {x, y} is a strong antichain, then (P, ≤) cannot be a lattice (or even a meet semilattice), since by definition, every two elements in a lattice (or meet semilattice) must have a common lower bound. Thus lattices have only trivial strong antichains (i.e., strong antichains of cardinality at most 1). (Wikipedia).
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From playlist Chemistry
Chemistry - Acids & Bases Fundamentals (21 of 35) What Is A Strong Acid?
Visit http://ilectureonline.com for more math and science lectures! In this video I will explain "What is a strong acid?" (A "strong" acid is "weak".)
From playlist CHEMISTRY 22 ACIDS AND BASES
Chemistry - Acids & Bases Fundamentals (22 of 35) What Is A Weak Acid?
Visit http://ilectureonline.com for more math and science lectures! In this video I will explain "What is a weak acid?" (A "weak" acid is "strong".)
From playlist CHEMISTRY 22 ACIDS AND BASES
Christian Gaetz: "Antichains and intervals in the weak order"
Asymptotic Algebraic Combinatorics 2020 "Antichains and intervals in the weak order" Christian Gaetz - Massachusetts Institute of Technology Abstract: The weak order is the partial order on the symmetric group S_n (or other Coxeter group) whose cover relations correspond to simple transp
From playlist Asymptotic Algebraic Combinatorics 2020
Chemistry - Acids & Bases (31 of 45) Comparing Acid Strengths Using % Concentrations
Visit http://ilectureonline.com for more math and science lectures! In this video I will explain the % ionized of a strong, weak, weaker, and very weak acid.
From playlist CHEMISTRY 22 ACIDS AND BASES
IB Strong and Weak Acids and bases
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From playlist IB Chemistry
Extremal Combinatorics with Po-Shen Loh 04/01 Wed - 2
Carnegie Mellon University is protecting the community from the COVID-19 pandemic by running courses online for the Spring 2020 semester. This is the video stream for Po-Shen Loh’s PhD-level course 21-738 Extremal Combinatorics. Professor Loh will not be able to respond to questions or com
From playlist CMU PhD-Level Course 21-738 Extremal Combinatorics
How To Memorize The Strong Acids and Strong Bases
This chemistry video tutorial explains how to memorize the 7 strong acids and strong bases. Strong acids dissociate completely where as weak acids dissociate partially. Strong Bases are usually soluble compounds that release hydroxide ions into solution. My Website: https://www.video-
From playlist New AP & General Chemistry Video Playlist
Identifying Strong Electrolytes, Weak Electrolytes, and Nonelectrolytes - Chemistry Examples
This chemistry video tutorial explains how to identify weak electrolytes, strong electrolytes, and nonelectrolytes. Strong electrolytes including strong acids and bases as well as soluble ionic compounds that ionize completely in solution. Weak electrolytes include weak acids and bases a
From playlist New AP & General Chemistry Video Playlist
MIT 6.042J Mathematics for Computer Science, Spring 2015 View the complete course: http://ocw.mit.edu/6-042JS15 Instructor: Albert R. Meyer License: Creative Commons BY-NC-SA More information at http://ocw.mit.edu/terms More courses at http://ocw.mit.edu
From playlist MIT 6.042J Mathematics for Computer Science, Spring 2015
Anna De Mier: Approximating clutters with matroids
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From playlist Combinatorics
Calculating the pH of a weak acid More free lessons at: http://www.khanacademy.org/video?v=dencuBNp_Ck
From playlist Chemistry
Fedor Petrov: "Inequalities for posets"
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From playlist Asymptotic Algebraic Combinatorics 2020
Assaf Rinot : Distributive Aronszajn trees
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From playlist Logic and Foundations
Chemistry - Acids & Bases (33 of 45) Weak Bases and Base Ionization Constants
Visit http://ilectureonline.com for more math and science lectures! In this video I will explain weak bases and its base ionization constants.
From playlist CHEMISTRY 22 ACIDS AND BASES
Extremal Combinatorics with Po-Shen Loh 04/03 Fri
Carnegie Mellon University is protecting the community from the COVID-19 pandemic by running courses online for the Spring 2020 semester. This is the video stream for Po-Shen Loh’s PhD-level course 21-738 Extremal Combinatorics. Professor Loh will not be able to respond to questions or com
From playlist CMU PhD-Level Course 21-738 Extremal Combinatorics
Assaf Rinot: Chain conditions, unbounded colorings and the C-sequence spectrum
Recording during the meeting "15th International Luminy Workshop in Set Theory" the September 23, 2019 at the Centre International de Rencontres Mathématiques (Marseille, France) Filmmaker: Guillaume Hennenfent Find this video and other talks given by worldwide mathematicians on CIRM's A
From playlist Logic and Foundations
Itay Neeman: Reflection of clubs, and forcing principles at ℵ2
Find this video and other talks given by worldwide mathematicians on CIRM's Audiovisual Mathematics Library: http://library.cirm-math.fr. And discover all its functionalities: - Chapter markers and keywords to watch the parts of your choice in the video - Videos enriched with abstracts, b
From playlist Logic and Foundations
IB Chemistry Acids and bases Topic 8.4 Strong and weak acids and bases
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Wolfram Physics Project: A Discussion with Fay Dowker
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From playlist Wolfram Physics Project Livestream Archive