Niles Johnson
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A lovely video showing Coxeter enjoying reflections. Indeed worth watching!
This Youtube clip has only 39 views. It was filmed in the 60's, and it stars Coxeter on reflections. Worth watching.
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This channel is getting crazy
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Once again xkcd has me pegged.

https://xkcd.com/1982/
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Wikiquote edit-a-thon - Saturday, May 12th, 2018

TL;DR: We’re holding a distributed Wikipedia edit-a-thon on Saturday, May 12th, 2018 from 10am to improve the visibility of women mathematicians on the Wikiquotes Mathematics page. Join in from wherever you are! Details below. Extension and abstraction…
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An update on the kilogram

If you haven't heard yet, the modern crisis in measurement known as the kilogram is set to be resolved this year. I've learned a little more about the schedule and plans, but first a review: The basic problem is that, unlike the other modern SI units, the kilogram is still defined by a physical object (in a vault in Paris), and we know it has been changing mass!!! Of course, that object is -- by definition -- a kilogram, so no one can say how much or in what way it's been changing. But it is definitely changing. The global measurement community has been working steadily on resolving this for years; they had hoped to settle it in 2014, but the measurements were not fine enough. We're on track for 2018! See [1], [2], or [3] below for more background.

Now the new stuff

Popular articles have been sketchy on details of the change, so I periodically dig around for more info. Here's what I have learned:

* The redefinition of kg is set for November 16, 2018 -- the Friday of a week-long meeting [4].

* One of the difficulties in implementing the new kg is making a Kibble (Watt) balance where one side is in a vacuum and the other is in open air -- you have to account for the buoyancy of the open-air object in air! This has (I think) been resolved; see [1] and [4].

* There is a World Metrology Day each year, on May 20. This year the theme is "constant evolution" -- get it?! (And yes, the metrology community does measure the impact of World Metrology Day -- see [4] again -- isn't that lovely? :)

* The body that does this is the General Conference on Weights and Measures, abbreviated CGPM for the French name (ah, the French). Wikipedia has a nice article about their activities [5] and it's where I found [4].

* It was at the 2003 meeting of CGPM that the metrology community settled the comma v.s. dot issue in writing numbers [6]. The specific language is worth reading, because it shows that these people are not messing around! Their conclusion: You can use either a dot . or comma , to separate the whole-number part from the decimal part of a number, and you may not use this punctuation anywhere else in the number. For readability, you are allowed to use spaces to separate digits into groups of three, but this is optional.

[1] https://www.nist.gov/pml/productsservices/redefining-kilogram
[2] https://en.wikipedia.org/wiki/Kibble_balance
[4] http://www.sim-metrologia.org.br/docs/2016Presentations/BIPM%202016.pdf
[5] https://en.wikipedia.org/wiki/General_Conference_on_Weights_and_Measures
[6] https://www.bipm.org/en/CGPM/db/22/10/

http://worldmetrologyday.org/
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I want to know what causes gun violence and what are the best ways to prevent it. US law prevents the CDC from funding such research since the mid-90s -- this is the Dickey amendment. No other major funding exists for such research, and so the "debate" about how to stop gun violence proceeds like a juvenile shouting match with ill-informed positions on all sides. And while we waste our time, people keep using guns to kill people, and I do wonder why.

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My brother is selling this basket. It's expensive, but he can't fit it in his house. Even if you don't know someone who might want it, check out the description -- it's fun. Here's a sample:

You will see from "Google-ing" that trying to estimate a value for this basket is difficult. Why? Because it's priceless, that's why. Much smaller baskets can be thousands, larger ones are hard to find. You may very well come across a few photos of THIS basket if you image search "Giant Seri Basket." Anyway, I started the bidding really low - I have never been good at eBay anyway.

It's obviously handmade and amazingly sturdy. I am told three women crafted it, but I am trying to get some more information - which I will pass along to the winning bidder if I get any. I am selling it because I can't get it into my house. I don't have a double-door and don't want to remove a window (although I did seriously consider it - as I LOVE this basket).

Feel free to contact me with any questions or comments. If you would like additional photos just let me know what you had in mind and I can take them. Good luck to all of you.

NOTE: Although this item was hand-crafted by descendants of the indigenous Seri Native People, the United States of America does not recognize the Seri people as an "official" tribe (they are native to North America, but not really the US proper). Therefore, this item is NOT "Native American made" but rather crafted in a tradition by natives to the North American continent.