BLOGS

Born: Aug. 26, 1918
Died: Feb. 24, 2020
Hometown: White Sulphur Springs, WV
Education: B.S., Mathematics and French, West Virginia State College, 1937
Hired by NACA: June 1953
Retired from NASA: 1986
Actress Playing Role in Hidden Figures: Taraji P. Henson

Topics: African Americans, Black History Month, Diversity in Science, Mathematics, NASA, Spaceflight, STEM, Women in Science

Being handpicked to be one of three black students to integrate West Virginia’s graduate schools is something that many people consider one of their life’s most notable moments. Still, it’s just one of several breakthroughs that have marked Katherine Johnson’s long and remarkable life. Born in White Sulphur Springs, West Virginia, in 1918, her intense curiosity and brilliance with numbers vaulted her ahead several grades in school. By 13, she was attending the high school on the campus of historically black West Virginia State College. At 18, she enrolled in the college itself, where she made quick work of the school’s math curriculum and found a mentor in math professor W. W. Schieffelin Claytor, the third African American to earn a PhD in mathematics. She graduated with highest honors in 1937 and took a job teaching at a black public school in Virginia. 

When West Virginia decided to quietly integrate its graduate schools in 1939, West Virginia State’s president, Dr. John W. Davis, selected her and two men to be the first black students offered spots at the state’s flagship school, West Virginia University. She left her teaching job and enrolled in the graduate math program. At the end of the first session, however, she decided to leave school to start a family with her first husband, James Goble.  She returned to teaching when her three daughters got older, but it wasn’t until 1952 that a relative told her about open positions at the all-black West Area Computing section at the National Advisory Committee for Aeronautics’ (NACA’s) Langley laboratory, headed by fellow West Virginian Dorothy Vaughan. Katherine and her husband decided to move the family to Newport News, Virginia, to pursue the opportunity, and Katherine began work at Langley in the summer of 1953. Just two weeks into her tenure in the office, Dorothy Vaughan assigned her to a project in the Maneuver Loads Branch of the Flight Research Division, and Katherine’s temporary position soon became permanent. She spent the next four years analyzing data from flight tests and worked on the investigation of a plane crash caused by wake turbulence. As she was wrapping up this work her husband died of cancer in December 1956.

The 1957 launch of the Soviet satellite Sputnik changed history—and Johnson’s life. In 1957, she provided some of the math for the 1958 document Notes on Space Technology, a compendium of a series of 1958 lectures given by engineers in the Flight Research Division and the Pilotless Aircraft Research Division (PARD). Engineers from those groups formed the core of the Space Task Group, the NACA’s first official foray into space travel. Johnson, who had worked with many of them since coming to Langley, “came along with the program” as the NACA became NASA later that year. She did trajectory analysis for Alan Shepard’s May 1961 mission Freedom 7, America’s first human spaceflight. In 1960, she and engineer Ted Skopinski coauthored Determination of Azimuth Angle at Burnout for Placing a Satellite Over a Selected Earth Position, a report laying out the equations describing an orbital spaceflight in which the landing position of the spacecraft is specified. It was the first time a woman in the Flight Research Division had received credit as an author of a research report.

In 1962, as NASA prepared for the orbital mission of John Glenn, Johnson was called upon to do the work that she would become most known for. The complexity of the orbital flight required the construction of a worldwide communications network, linking tracking stations around the world to IBM computers in Washington, Cape Canaveral in Florida, and Bermuda. The computers had been programmed with the orbital equations that would control the trajectory of the capsule in Glenn’s Friendship 7 mission from liftoff to splashdown, but the astronauts were wary of putting their lives in the care of the electronic calculating machines, which were prone to hiccups and blackouts. As a part of the preflight checklist, Glenn asked engineers to “get the girl”—Johnson—to run the same numbers through the same equations that had been programmed into the computer, but by hand, on her desktop mechanical calculating machine.  “If she says they’re good,’” Katherine Johnson remembers the astronaut saying, “then I’m ready to go.” Glenn’s flight was a success and marked a turning point in the competition between the United States and the Soviet Union in space.

Katharine Johnson Biography, Margot Lee Shetterly, NASA

Some fireflies have a mystifying gift for flashing their abdomens in sync. New observations are overturning long-accepted explanations for how the synchronization occurs, at least for some species.

Topics: Biology, Biomimetics, Biotechnology, Computer Modeling, Mathematics

In Japanese folk traditions, they symbolize departing souls or silent, ardent love. Some Indigenous cultures in the Peruvian Andes view them as the eyes of ghosts. And across various Western cultures, fireflies, glow-worms, and other bioluminescent beetles have been linked to a dazzling and at times contradictory array of metaphoric associations: “childhood, crop, doom, elves, fear, habitat change, idyll, love, luck, mortality, prostitution, solstice, stars and fleetingness of words and cognition,” as one 2016 review noted.

Physicists revere fireflies for reasons that might seem every bit as mystical: Of the roughly 2,200 species scattered around the world, a handful has the documented ability to flash in synchrony. In Malaysia and Thailand, firefly-studded mangrove trees can blink on the beat as if strung up with Christmas lights; every summer in Appalachia, waves of eerie concordance ripple across fields and forests. The fireflies’ light shows lure mates and crowds of human sightseers, but they have also helped spark some of the most fundamental attempts to explain synchronization, the alchemy by which elaborate coordination emerges from even very simple individual parts.

Orit Peleg remembers when she first encountered the mystery of synchronous fireflies as an undergraduate studying physics and computer science. The fireflies were presented as an example of how simple systems achieve synchrony in Nonlinear Dynamics and Chaos, a textbook by the mathematician Steven Strogatz that her class was using. Peleg had never even seen a firefly, as they are uncommon in Israel, where she grew up.

“It’s just so beautiful that it somehow stuck in my head for many, many years,” she said. But by the time Peleg began her own lab, applying computational approaches to biology at the University of Colorado and at the Santa Fe Institute, she had learned that although fireflies had inspired a lot of math, quantitative data describing what the insects were actually doing was scant.

How Do Fireflies Flash in Sync? Studies Suggest a New Answer. Joshua Sokol, Quanta Magazine

Which states have dropped mask mandates and why, Marlene Lenthang, Yahoo News

Topics: Biology, COVID-19, Dark Humor, Existentialism, Mathematics, Politics

Figures often beguile me, particularly when I have the arranging of them myself; in which case the remark attributed to Disraeli would often apply with justice and force: “There are three kinds of lies: lies, damned lies, and statistics.”

Mark Twain, also: https://en.wikipedia.org/wiki/Lies,_damned_lies,_and_statistics

A follow-up to Tuesday's post: VOC...

‘No Thank You, Mr. President’: GOP States Still End Mask Mandates Despite Covid-19 Rise And Warnings From Biden, CDC, Alison Durkee, Forbes Business, April 2, 2021

Having some "fun" with mathematics. It's dark humor for all you young libertarians.

The current US COVID deaths are 573, 988 from https://ncov2019.live/.

The current US population is 332,494,997 from Worldometers.info. Each link updates minute-by-minute, so by the time you read this, these figures will have changed.

(US COVID deaths/current US population) x 100 = 0.17%. Round up to 0.2%.

That's pretty low.

For the "freedom-loving libertarians" spring breaking in Miami, or Fort Lauderdale, Florida, and Corpus Christi, Texas - a thought experiment:

100,000 of you are about to dive into the ocean.

There is a 0.2% = 0.2/100 chance some of you will get devoured by sharks.

100,000 x (0.2/100) = 200 dead spring breakers.

So, out of 100,000 - 200 = 99,800, or 99.8% have a very good chance of not becoming "chicken of the sea," and surviving your spring break. The dilemma is, there will still be blood in the water. Blood that carries pathogens that despite your "Y" swimming lessons and the saline environment, you might ingest red tide, and suffer the consequences.

The problem is, your 0.2% chance is not zero. Under normal circumstances (and pandemics are once-in-a-century "not normal"), there's no libertarian case for this:

Image Source: Link below

Topics: Biology, Chemistry, COVID-19, Mathematics, Physics

The year 2020 has been defined by the COVID-19 pandemic: The novel coronavirus responsible for it has infected millions of people and caused more than a million deaths. Like HIV, Zika, Ebola, and many influenza strains, the coronavirus made the evolutionary jump from animals to humans before wreaking widespread havoc. The battle to control it continues. When a disease outbreak is identified—usually through an anomalous spike in cases with similar symptoms—scientists rush to understand the new illness. What type of microbe causes the infection? Where did it come from? How does the infection spread? What are its symptoms? What drugs could treat it? In the current epidemic, science has proceeded at a frenetic pace. Virus genomes are quickly sequenced and analyzed, case and death numbers are visualized daily, and hundreds of preprints are shared every day.

Some scientists rush for their microscopes and lab coats to study a new infection; others leap for their calculators and code. A handful of metrics can characterize a new outbreak, guide public health responses, and inform complex models that can forecast the epidemic’s trajectory. Infectious disease epidemiologists, mathematical biologists, biostatisticians, and others with similar expertise try to answer several questions: How quickly is the infection spreading? What fraction of transmission must be blocked to control the spread? How long is someone infectious? How likely are infected people to be hospitalized or die?

Physics is often considered the most mathematical science, but theory and rigorous mathematical analysis also underlie ecology, evolutionary biology, and epidemiology.¹ Ideas and people constantly flow between physics and those fields. In fact, the idea of using mathematics to understand infectious disease spread is older than germ theory itself. Daniel Bernoulli of fluid-mechanics fame devised a model to predict the benefit of smallpox inoculations² in 1760, and Nobel Prize-winning physician Ronald Ross created mathematical models to encourage the use of mosquito control to reduce malaria transmission.³ Some of today’s most prolific infectious disease modelers originally trained as physicists, including Neil Ferguson of Imperial College London, an adviser to the UK government on its COVID-19 response, and Vittoria Colizza of Sorbonne University in Paris, a leader in network modeling of disease spread.

This article introduces the essential mathematical quantities that characterize an outbreak, summarizes how scientists calculate those numbers, and clarify the nuances in interpreting them. For COVID-19, estimates of those quantities are being shared, debated, and updated daily. Physicists are used to distilling real-world complexity into meaningful, parsimonious models, and they can serve as allies in communicating those ideas to the public.

The math behind epidemics, Alison Hill, Physics Today

Alison Hill is an assistant professor in the Institute for Computational Medicine and the infectious disease dynamics group at Johns Hopkins University in Baltimore, Maryland. She is also a visiting scholar at Harvard University in Cambridge, Massachusetts.

New 5G antennas (left) are smaller than 4G ones (right). Upcoming 5G networks will use higher-frequency radio spectrum, which will provide more bandwidth and enable the faster data-transfer rates that new technologies, such as autonomous vehicles, smart energy grids, and internet-of-things devices, will demand. (Photos by KPhrom/Shutterstock.com.)

Topics: Electromagnetic Radiation, Mathematics, Stochastic Modeling, Research, Satellite, Weather

Fifth-generation broadband wireless threatens weather forecasting
Alex Lopatka, Physics Today