Thomas Egense

16,537 followers -

I have a math blog and I am generally interested in all kinds of scientific matters. I use mathematics to create art – you can check out my album. I try to find unique content for my posts,which are mostly of scientific nature.

I have a math blog and I am generally interested in all kinds of scientific matters. I use mathematics to create art – you can check out my album. I try to find unique content for my posts,which are mostly of scientific nature.

16,537 followers

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50th Mersenne Prime Discovered

**2^77232917 - 1 is prime**

It was discovered on December 26, 2017 by Jonathan Pace, and verified to be a prime by GIMPS using four different programs on four different hardware configurations.

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**Breakthrough Prize in Mathematics 2017 awarded**

They proved the number (different shapes) of solutions for Diophantine polynomial Equations over the complex numbers is always finite.

Breakthrough Prize in mathematics: Christopher Hacon [1] and James McKernan [2].

New Horizons in Mathematics Prizes Awarded to Aaron Naber [3], Maryna Viazovska [4], Zhiwei Yun [5], and Wei Zhang [6].

[1] https://en.wikipedia.org/wiki/Christopher_Hacon

[2] https://en.wikipedia.org/wiki/James_McKernan

[3] http://www.math.northwestern.edu/~anaber/

[4] https://en.wikipedia.org/wiki/Maryna_Viazovska

[5] https://en.wikipedia.org/wiki/Zhiwei_Yun

[6] https://en.wikipedia.org/wiki/Wei_Zhang_(mathematician)

New Horizons in Mathematics Prizes Awarded to Aaron Naber [3], Maryna Viazovska [4], Zhiwei Yun [5], and Wei Zhang [6].

[1] https://en.wikipedia.org/wiki/Christopher_Hacon

[2] https://en.wikipedia.org/wiki/James_McKernan

[3] http://www.math.northwestern.edu/~anaber/

[4] https://en.wikipedia.org/wiki/Maryna_Viazovska

[5] https://en.wikipedia.org/wiki/Zhiwei_Yun

[6] https://en.wikipedia.org/wiki/Wei_Zhang_(mathematician)

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**Dynamic graph of HTML tags usages from 2005-2017 in the Danish Netarchive**

See the relative frequency of HTML-tags over time on webpages. What happened to the hated blink-tag? How fast was canvas-tag embraced by the community? See for yourself!

The tags registered are not limited to legal HTML tag, but anything that is marked on a tag on a HTML page. Try sarcasm-tag etc.

The Danish Netarchive consists of 10.5 billion harvested HTML pages from 2005 up to today. This amounts to 2.4 Petabyte of archived data.

Tags Demo: http://labs.statsbiblioteket.dk/tags/

(Labs main page: http://www.statsbiblioteket.dk/sblabs/)

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The Windshield Phenomenon

Troubling news about a 80% decrease of the biomass of insects.

http://www.sciencemag.org/news/2017/05/where-have-all-insects-gone

Troubling news about a 80% decrease of the biomass of insects.

http://www.sciencemag.org/news/2017/05/where-have-all-insects-gone

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**One of John Conway's open math problems solved.**

The famous mathematician John Horton Conway has a list of 5 open problems and one of the problems now has been solved. And it is one that is easy to understand for non-mathematicians as well.

Numberphile just did a video with the solution:

https://www.youtube.com/watch?v=3IMAUm2WY70

Any cycle would have been a counter example, but James David actually found a fix-point - a cycle of length 1.

It reminds me of the Collatz' conjecture. Mathematicians has no clue how to maky any progress on the conjecture. Best hope is someone finding a counter example.

John Conway's 5 open problems:

https://oeis.org/A248380/a248380.pdf

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**Is pentagon tiling of the plane finally solved?**

There are 15 different known families of pentagon tilings, and one of them was just found 2 years ago. (See my previous post)

But a recent paper just claims these 15 families are the only ones.

Recreational mathematics expert +Ed Pegg made a post about a few days ago on reddit/r/math.

From the Abstract:

"We present an exhaustive search of all families of convex pentagons

which tile the plane. This research show that there are no more than

the already 15 known families. In particular, this imply that there is

no convex polygon which allows only non-periodic tilings."

Article: http://perso.ens-lyon.fr/michael.rao/publi/penta.pdf

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Edit: 2 Years old news. (I had not seen it)

New convex pentagon tiling found bringing the number of known convex pentagon tilings up to 15.

New convex pentagon tiling found bringing the number of known convex pentagon tilings up to 15.

Hurray a new convex pentagon tiling! That's 15.

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**SolrWayback - another Wayback Machine implementation**

If you are involved with Web archiving my SolrWayback Machine may interest you. Fresh from my blog post at work:

#wayback #waybackmachine #resaw #warc #webarchive

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**Automated improvement of search in low quality OCR using Word2Vec**

The Word2Vec algorithm used to detect OCR errors and custom code on top of that to make search work in spite of poor quality OCR text.

Abstract for my paper to be presented at Digital Humanities in the Nordic Countries 2nd Conference 2017.

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Interesting!

For some reason this makes me think of Dirk Gently's Holistic Detective Agency...

**Need improved solution to "Moving Sofa" problem.**For some reason this makes me think of Dirk Gently's Holistic Detective Agency...

**Romik's ambidextrous sofa**

The

**ambidextrous moving sofa problem**is to find the planar shape with the biggest area that can slide through right-angled turns both to the right and to the left in a hallway of width 1.

Earlier this year Dan Romik, a mathematician at the University of California Davis, found the best known solution to this problem! He created this animated gif of it, too. His shape is bounded by 18 curves, each of which is either part of a circle, or part of a curve described by a polynomial equation of degree 6.

Nobody has proved his solution is optimal. We're not even sure that it's

**locally optimal**, meaning that you can't make slight changes in his shape that increase the area and get a shape that still fits down the hallway. This is an interesting challenge.

For more, including the precise area of this shape, try my blog article on

*Visual Insight*:

http://blogs.ams.org/visualinsight/2016/12/15/romiks-ambidextrous-sofa/

I hope you're all having a great holiday!

Each year I try to think of things I can stop doing... so I can do more new stuff. In 2017, I will try to take a year-long break from posting articles on

*Visual Insight*. I've been doing two a month for quite a while, I've done 81 of them, and I'm running out of enthusiasm. Also, right now, a lot of my energy is going into the Azimuth Backup Project. So, maybe I will save up ideas and restart

*Visual Insight*in 2018. But perhaps I'll end with a bang on January 1st, 2017.

#geometry

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