In mathematics, specifically in the study of topology and open covers of a topological space X, a star refinement is a particular kind of refinement of an open cover of X. The general definition makes sense for arbitrary coverings and does not require a topology. Let be a set and let be a covering of , i.e., . Given a subset of then the star of with respect to is the union of all the sets that intersect , i.e.: Given a point , we write instead of . Note that . The covering of is said to be a refinement of a covering of if every is contained in some . The covering is said to be a barycentric refinement of if for every the star is contained in some . Finally, the covering is said to be a star refinement of if for every the star is contained in some . Star refinements are used in the definition of fully normal space and in one definition of uniform space. It is also useful for stating a characterization of paracompactness. (Wikipedia).
This test was based on NightHawkinLight's formula of Starlite.
From playlist NightHawkInLight Community Video Responses!
Spectroscopy - Splitting the Starlight
How do we know what stars are made of? Starlight contains millions of fingerprints - spectral lines, which are produced by chemical compounds in the form of molecules, atoms, which are present in the atmospheres of stars and planets. The films shows how scientists decode stellar light and
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DIY StarLite Refinement - Burning WIth Buba-ish - Part 1
Today boys and girls... we are refining NightHawkInLight's DIY Starlite recipe https://youtu.be/aqR4_UoBIzY to find out what ratio works best and if adding anything else improves it's thermal characteristics. at then end I melt some copper on a sheet that is only 1/16" of an inch thick!
From playlist NightHawkInLight Community Video Responses!
Teach Astronomy - Pulsation Period
http://www.teachastronomy.com/ Just like a bell or any mechanical object, stars have a particular frequency or timescale when they tend to vibrate in response to an external disturbance. If the time that it takes for energy to dam up in the atmosphere of a giant star corresponds to the na
From playlist 15. Stars 2
Astronomy - Ch. 17: The Nature of Stars (12 of 37) Brightness Explained (2 Ways)
Visit http://ilectureonline.com for more math and science lectures! In this video I will explain the brightness in 2 ways: The amount of visible light an objects puts out per unit time and how bright it appears when it reaches the Earth (lumens). Next video can be seen at: http://youtu.b
From playlist ASTRONOMY 17 STARS AND THE H-R DIAGRAM
Teach Astronomy - Theory of Star Formation
http://www.teachastronomy.com/ Star formation is very complex. Thus when astronomers talk about the theory of star formation they're talking about a theory that is not yet highly refined where many details remain to be worked out. Star formation occurs in dense regions from which light c
From playlist 15. Stars 2
Substructural Type Theory - Zeilberger
Noam Zeilberger IMDEA Software Institute; Member, School of Mathematics March 22, 2013 For more videos, visit http://video.ias.edu
From playlist Mathematics
Astronomy - Ch. 24: Variable Stars (1 of 26) Variable Star Types
Visit http://ilectureonline.com for more math and science lectures! To donate: http://www.ilectureonline.com/donate https://www.patreon.com/user?u=3236071 We will learn that a variable star is a star whose “apparent brightness” changes or fluctuates over time a seen from Earth. There are
From playlist ASTRONOMY 24 VARIABLE STARS
Astronomy - Ch. 17: The Nature of Stars (13 of 37) Luminosity and Brightness (Luminosity Defined)
Visit http://ilectureonline.com for more math and science lectures! In this video I will define luminosity as all radiation emitted and brightness as % of energy radiate from visible light. Next video can be seen at: http://youtu.be/zuMrgm1EIpU
From playlist ASTRONOMY 17 STARS AND THE H-R DIAGRAM
The Star of the Eclipse: The Sun | Total Solar Eclipse | Exploratorium
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From playlist Total Solar Eclipse
Charles Fefferman : Whitney problems and real algebraic geometry
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 Analysis and its Applications
Math 131 112116 Uniform Convergence and Integration
Quick introduction to Riemann integrability: partitions, upper and lower sums, upper and lower Riemann integrals, Riemann integrals. Definition: refinement of a partition; common refinement of two partitions. Observation: lower (upper) sums increase (decrease) for a refinement. Theorem:
From playlist Course 7: (Rudin's) Principles of Mathematical Analysis
Richard Thomas - Vafa-Witten Invariants of Projective Surfaces 5/5
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From playlist 2021 IHES Summer School - Enumerative Geometry, Physics and Representation Theory
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David Burns March 25, 2011 For more videos, visit http://video.ias.edu
From playlist Mathematics
Tim Scrimshaw - Canonical Grothendieck polynomials with free fermions
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From playlist Combinatorics and Arithmetic for Physics: Special Days 2022
In this video, we give an important motivation for studying Topological Cyclic Homology, so called "trace methods". Feel free to post comments and questions at our public forum at https://www.uni-muenster.de/TopologyQA/index.php?qa=tc-lecture Homepage with further information: https://w
From playlist Topological Cyclic Homology
on the Brumer-Stark Conjecture (Lecture 2) by Samit Dasgupta
PROGRAM ELLIPTIC CURVES AND THE SPECIAL VALUES OF L-FUNCTIONS (HYBRID) ORGANIZERS: Ashay Burungale (CalTech/UT Austin, USA), Haruzo Hida (UCLA), Somnath Jha (IIT Kanpur) and Ye Tian (MCM, CAS) DATE: 08 August 2022 to 19 August 2022 VENUE: Ramanujan Lecture Hall and online The program pla
From playlist ELLIPTIC CURVES AND THE SPECIAL VALUES OF L-FUNCTIONS (2022)
Challenges Towards a Post Scarcity World & the Bullshit Economics of Star Trek - Dare To Be Stupid 4
This time on Speaking of Bitcoin: George Frankly is back for the fourth installment of his Dare To Be Stupid Series. Have any questions or comments? Send us an email at adam@speakingof.bitcoin.show Prefer the podcast version? Subscribe for free: Apple: https://podcasts.apple.com/us/pod
From playlist Podcast: Speaking of Bitcoin
Teach Astronomy - Cycle of Star Birth and Death
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From playlist 16. Stars 3
on the Brumer-Stark Conjecture (Lecture 1) by Samit Dasgupta
PROGRAM ELLIPTIC CURVES AND THE SPECIAL VALUES OF L-FUNCTIONS (HYBRID) ORGANIZERS: Ashay Burungale (CalTech/UT Austin, USA), Haruzo Hida (UCLA), Somnath Jha (IIT Kanpur) and Ye Tian (MCM, CAS) DATE: 08 August 2022 to 19 August 2022 VENUE: Ramanujan Lecture Hall and online The program pla
From playlist ELLIPTIC CURVES AND THE SPECIAL VALUES OF L-FUNCTIONS (2022)