Of all mathematical operations, addition is the most basic: It’s what we learn first in school. Historically, it is the most ancient. While the simple task of getting the sum of two numbers is simple, sums of many numbers can easily turn into a challenging numerical problem if the number of summands is very large.
The Wolfram Language has several hundred built-in functions, ranging from sine to Heun. As a user, you can extend this collection in infinitely many ways by applying arithmetic operations and function composition. This could lead you to defining expressions of bewildering complexity, such as the following:
✕ f = SinhIntegral[ LogisticSigmoid[ ScorerHi[Tanh[AiryAi[HermiteH[-(1/2), x] - x + 1]]]]];
In 2020, Melbourne, Australia, had a 112-day lockdown of the entire city to help stop the spread of COVID-19. The wearing of masks was mandatory and we were limited to one hour a day of outside activity. Otherwise, we were stuck in our homes. This gave me lots of time to look into interesting problems I’d been putting off for years.
I was inspired by a YouTube video by David Oranchak, which looked at the Zodiac Killer’s 340-character cipher (Z340), which is pictured below. This cipher is considered one of the holy grails of cryptography, as at the time the cipher had resisted attacks for 50 years, so any attempts to find a solution were truly a moonshot.
Solving a 2,000-Year-Old MysteryIt’s not every day that a 2,000-year-old optics problem is solved. However, Rafael G. González-Acuña, a doctoral student at Tecnológico de Monterrey, set his sights on solving such a problem—spherical aberration in lenses. How can light rays focus on a single point, taking into account differing refraction? It was a problem that, according to Christiaan Huygens back in 1690, even Isaac Newton and Gottfried Leibniz couldn’t sort out, and was formulated two millennia ago in Greek mathematician Diocles’s work, On Burning Mirrors.
But González-Acuña and his colleagues realized that today, they had the use of the Wolfram Language and its computational tools to solve this age-old problem. The result? A breakthrough publication that outlines an analytical solution to why and how lensed images are sharper in the center than at the edges, with 99.999999999% accuracy simulating 500 light beams.
As it happens, González-Acuña was recently at the Wolfram Summer School, and we had the opportunity to ask him a little bit about his work.
Mapping an Ancient EmpireGeocomputation is an indispensable modern tool for analyzing and viewing large-scale data such as population demographics, natural features and political borders. And if you’ve read some of my other posts, you can probably tell that I like working with maps. Recently, a Wolfram Community member asked:
“How do I make an interactive map of the Byzantine Empire through the years?”
To figure out a solution, we'll tap into the Wolfram Knowledgebase for some historical entities, as well as some of the high-level geocomputation and visualizations of the Wolfram Language. Once we’ve created our brand-new function, we’ll submit it to the Wolfram Function Repository for anyone to use.
The Wolfram|Alpha Story
Today it’s 10 years since we launched Wolfram|Alpha. At some level, Wolfram|Alpha is a never-ending project. But it’s had a great first 10 years. It was a unique and surprising achievement when it first arrived, and over its first decade it’s become ever stronger and more unique. It’s found its way into more and more of the fabric of the computational world, both realizing some of the long-term aspirations of artificial intelligence, and defining new directions for what one can expect to be possible. Oh, and by now, a significant fraction of a billion people have used it. And we’ve been able to keep it private and independent, and its main website has stayed free and without external advertising.
This morning, representatives of more than 100 countries agreed on a new definition of the base units for all weights and measures. Here’s a picture of the event that I took this morning at the Palais des Congrès in Versailles (down the street from the Château):
An important vote for the future weights and measures used in science, technology, commerce and even daily life happened here today. This morning’s agreement is the culmination of at least 230 years of wishing and labor by some of the world’s most famous scientists. The preface to the story entails Galileo and Kepler. Chapter one involves Laplace, Legendre and many other late-18th-century French scientists. Chapter two includes Arago and Gauss. Some of the main figures of chapter three (which I would call “The Rise of the Constants”) are Maxwell and Planck. And the final chapter (“Reign of the Constants”) begins today and builds on the work of contemporary Nobel laureates like Klaus von Klitzing, Bill Phillips and Brian Josephson.
I had the good fortune to witness today’s historic event in person.
Revisiting the Disputed Federalist Papers: Historical Forensics with the Chaos Game Representation and AI
Between October 1787 and April 1788, a series of essays was published under the pseudonym of “Publius.” Altogether, 77 appeared in four New York City periodicals, and a collection containing these and eight more appeared in book form as The Federalist soon after. As of the twentieth century, these are known collectively as The Federalist Papers. The aim of these essays, in brief, was to explain the proposed Constitution and influence the citizens of the day in favor of ratification thereof. The authors were Alexander Hamilton, James Madison and John Jay.On July 11, 1804, Alexander Hamilton was mortally wounded by Aaron Burr, in a duel beneath the New Jersey Palisades in Weehawken (a town better known in modern times for its tunnels to Manhattan and Alameda). Hamilton died the next day. Soon after, a list he had drafted became public, claiming authorship of more than sixty essays. James Madison publicized his claims to authorship only after his term as president had come to an end, many years after Hamilton’s death. Their lists overlapped, in that essays 49–58 and 62–63 were claimed by both men. Three essays were claimed by each to have been collaborative works, and essays 2–5 and 64 were written by Jay (intervening illness being the cause of the gap). Herein we refer to the 12 claimed by both men as “the disputed essays.”