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Mathematics

Happy 354/297 day!

on January 14, 2019

Today is January 19, 2019, 1/19/19!

The number 1.1919 can be expressed as the fraction 354/297 and the repeated fraction 1.\overline{1919} is 118/99 . Such a rational day!

The number 11919 is itself composite, expressible in terms of the primes 3, 29, and 137.

Let’s dive into 11919’s 19 side!

The featured image is a 19-sided star, a design by my daughter Virika that was inspired by the ceiling of one of the Taj Mahal’s entrances

This tiling from the tomb of Shaikh Salim Chisti comes close also

Maybe 19 sides.

Whether they are 19 sided or not, they are still amazing.

19 is the 8th prime number. It is also a Pierpont prime, a number that can be written as 2^u 3^v + 1 where in this case u = 1 and v = 2 .

19 has a special significance in the Bahá’í world where the are 19 days in each month and 19 months in the year, with about \sqrt{19} (intercalary) days leftover.

The sum of the integers 1 to 19 is 190 and the sum of the primes up to 19 is 100!

Any day is a good day to meditate on the amazing patterns around us, especially a cold and rainy January Saturday!

BooksData ScienceMigration

The Little Shop of Data Science Stories

on December 31, 2018

I am happy to announce that The Little Shop of Stories bookstore in Decatur, GA is awesome for data science! A few blocks away from us, it is such a regional treasure for children’s books and events. Diane has brought game changing books, authors, and programs to Atlanta and environs.

But last week I was ecstatic when I came across a treasure of data visualization on the shelves.

Who knew data science could bring this much joy?

The book I am referring to is W. E. B. Du Bois’s Data Portraits: Visualizing Black America. But if you live in the Atlanta area, please get it at Little Shop — Amazon can make it without your dollars.

You may be aware of Dr W.E.B. DuBois work in championing and defining civil rights for peoples of the African diaspora during the first half of the twentieth century. You might be aware of his book The Souls of Black Folk , his leadership of the NAACP, and his intellectual nurturing of African independence efforts. But his work at the Atlanta University Center (now Clark Atlanta University) stands the test of time for how to do good data visualization.

Visualizing Black America pulls together the amazing visualizations that he and his AUC students developed for the 1900 Paris Exposition. They are beautiful, innovative, meticulous and tell the story of Black America at the beginning of the 20th century.

that he and his AUC students developed for the 1900 Paris Exposition. They are beautiful, innovative, meticulous and tell the story of Black America at the beginning of the 20th century.

We are so lucky in the Atlanta area to have a bookstore with the vision to stock this treasure. Stop through if you are in the ATL.

Uncategorized

A.I. without borders

on December 9, 2018

Some researchers from African countries were barred from attending last week’s  A.I. conference  in Montréal due to visa issues. 

The story is covered in this Wired article

The organizers of the Black in A.I. workshop were working around the clock with immigration experts, but at least 40 presenters were not able to attend. 

Even Justin Trudeau has promised an investigation, though after the fact.

This story again puts front and center the ways in which technologies that offer so much in the way of potential are being circumscribed by the diminishing commitment to open and fair borders.

A major AI conference will be hosted in Addis in 2020. Will that be a step towards opening the borders of research and development in AI?

Uncategorized

Missed Opportunities for Using Text in Data Visualization

on December 8, 2018

Data for Breakfast

Richard Brath, a partner at Uncharted Software and the author of Graph Analysis and Visualization, recently completed his Ph.D. thesis on using text in data visualization. Recently, Richard talked about his thesis with data visualization enthusiasts at Automattic. Before Richard’s talk, it seemed me that text has been treated as a “second-class citizen” in the data visualization world. But even I was surprised about the wealth of visual information that we can offer using text.

Richard Brath was kind enough to allow us to publish his talk for the global audience. You can find Richard’s blog at https://richardbrath.wordpress.com.

Enjoy the lecture.

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GeorgiaHistorySocial JusticeUncategorizedVoting

Who’s worse Brian Kemp or Lester Maddox?

on December 2, 2018

Feeling some despair headed back to Georgia, and the U.S. generally after a month in India.

It’s about this question: Will Brian Kemp govern Georgia like Lester Maddox?

Lester Maddox became the governor of Georgia during my childhood. He was openly racist, was famous for selling axe handles with which to beat down civil rights activists, and actively fought a state memorial immediately after Dr Martin Luther King was assassinated.

Until Brian Kemp, I don’t remember any Georgia governor who so actively and openly embraced race based voter suppression and racist immigration messages.

Yet Maddox apparently went on the most aggressive hiring of African Americans in the state’s history.

I’m finding solace knowing that people of color in Georgia nonviolently sacrificed their livelihoods and their lives to end the Maddox mode of governance.

Those sacrifices opened the door for people like Stacey Abrams, Andrew Young, and Jimmy Carter.

Our grandmothers and uncles and neighbors did this with an inner soul power (to quote Dr King) that could not be suppressed by axe handles or tear gas. I find strength knowing that we can call on that soul power to do the same again.

MathematicsTravel

Calculus and The Mother

on December 2, 2018

Last weekend we spent a beautiful afternoon with cousins at the Sri Aurobindo Ashram in Delhi. 

There was a lecture going on about the divine inspiration of Calculus — a meditation on how both Newton and Leibniz came to discoveries of infinite series and limits that led to the starting point for advanced maths.

As I pondered the spirit of The Mother, my mind went back to the visit we’d taken to the Jantar Mantar in Jaipur — an astronomical observatory built around the time of Newton’s discovery. Surely, a society that had the capacity to develop highly accurate astronomical predictions had the sophistication to develop the machinery for dealing with infinitesimal rates of change.

Newton — or more likely Leibniz — was indeed late to the game by at least 200 years! 

Keralan mathematician Nilakantha Somayaji in the 1400s seems to have worked out machinery for dealing with infinitesimal velocity and converging series.

This was in service of improving the accuracy of astronomical calculations. I’m not even sure if Somayaji’s work was used in the Jantar Mantar observatories, but there is now speculation that the Kerala school might well have been known to Leibniz.

Chalk another wonder up to globalization, I’ll give props to The Mother for the inspirations.

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