Showing posts with label #mathyear. Show all posts
Showing posts with label #mathyear. Show all posts

Saturday, September 18, 2021

Bees, and Spheres, Minerals and Becoming Crabs

There's so much science art being shared on Twitter this month for #SciArtSeptember. I have scheduled works for daily prompts for the whole month. I have also just finished working my way through the entire list of prompts for #mathyear - as well as  continuing ongoing bee-themed projects.

There was no summer camp for the last weeks of August and beginning of September before school, so I was pretty busy parenting, but here are some new works from the end of August and September so far.

The Leafcutter Bees, linocut and leaf prints by Ele Willoughby, 2021

 

I made a series of monoprints about leafcutter bees, and whimsically, in collaboration with leafcutter bees! These small, but multifarious native bees are important pollinators, who make nests for their babies using small telltale half-moon pieces they cut from leaves and petals. This work features two large linocuts of two leaf cutter bees: Megachile relativa and Megachile brevis. These linocuts are made on collaged Japanese washi papers and cellophane to capture the colours in their bodies and wings. Each print has its own array of leaf and petal prints from leaves and petals used by leaf cutter bees from my garden. The plants used include raspberries, roses (leaves and petals), lily of the valley, lilac, lemon balm, ash, thicket creeper, round-leaved Crane's bill and more. Each print is 17" tall by 12.5" wide (43.2 cm by 31.8 cm). 

Sphere Packing, linocut with collaged washi by Ele Willoughby, 2021

 

I have an ongoing thread of my #mathyear art on Twitter, and I was looking ahead at future prompts. I added a several portraits and other prints about math to fill out the remaining prompts, including this new item in my shop: a block print shows the two piles with the two possible close packing of equal spheres, each below a diagram of the plan view of the layout: Face-centered cubic (fcc) and hexagonal close packed (hcp). Each pile of spheres on water-colour paper with a deckle edge has its own unique assortment of collaged gorgeous Japanese washi papers. Each version of this print is unique.

The problem of how efficiently you can pack spheres into a volume has a long history in mathematics. It was Carl Friedrich Gauss who found the highest average density that can be achieved by lattice packing and the Kepler conjecture (as in Johannes Kepler) states that this is the highest density that can be achieved by any arrangement of spheres, either regular or irregular. When the famous mathematician David Hilbert set his 23 Problems of important unsolved problems in math in 1900, it included the question of what is the densest sphere packing. The question is generally considered solved since T.C. Hales proved the Kepler conjecture in 1998.

Though this may seem an abstract theoretical geometry problem there are real-life applications. It turns out, for instance, that many crystals with structures based on close-packed identical spheres of the fcc or hcp variety. 

 

Malachite, linocut, 8" x 8", by Ele Willoughby, 2021

There's also the annual social media battle of the minerals going on with #MINCUP2021. I always intended to make a series of mineral prints but never got passed making Quartz. I have managed to tie several of the minerals to existing prints and been tweeting those along with my votes, but I have managed to make one new pertinent print so far: Malachite. I have been using "cool physics and/or art applications" to determine my vote so malachite, often carved to make beautiful items, and a paint pigment since antiquity was obviously one to support. 

Jennifer Zee (ginkgozee on instagram and here on Etsy) has been working on an amazing series of mineral relief prints (including malachite and many others recently) and it reminded me I really wanted to have a whole colleciton. You should check out her work!

 

Porcelain crab, linocut by Ele Willoughby, 2021

For the #SciArtSeptember prompt evolving, I knew I had to talk about how things keep evolving into crabs! This is a hand-printed lino block print in black and red ink on white Japanese kozo (or mulberry) paper of a porcelain crab, Neopetrolisthes maculatus. Each print is 8” by 8” and printed by hand. Porcelain crabs are decapod crustaceans in the family Porcellanidae, which resemble true crabs but are in fact closer related to squat lobsters. They have flattened bodies as an adaptation for living in rock crevices. They first appeared in the Tithonian age of the Late Jurassic epoch, 145-152 million years ago. There are one of at least 5 groups of decapod crustaceans which have evolved to be more crab-shaped in a process known as carsinisation.

Tuesday, July 27, 2021

Mathematician Karen Uhlenbeck, Bubbles and Bubbling

Karen Keskulla Uhlenbeck, linocut detail, 9.25" x 12.5", variable edition on Japanese kozo paper with chine collé with suminagashi marbling, by Ele Willoughby, 2021


My latest #sciart (or, maybe #mathart) portrait is of mathematician Karen Uhlenbeck. Though a lot of her work is pertinent to physics, this was still a challenge to work out how to tell the story of her mathematics. A founder of modern geometric analysis, she won the 2019 Abel Prize for "her pioneering achievements in geometric partial differential equations, gauge theory, and integrable systems, and for the fundamental impact of her work on analysis, geometry and mathematical physics." Partial differential equations are pretty central to doing physics, and a sort of mathematics I really enjoy, but apart from that, I know what all the words mean in that previous sentence, but things like gauge theory and analysis aren't part of the math I've studied or used in my own research. As we move forward in time, depicting contemporary (or near contemporary) mathematics is increasingly challenging because it's beyond my ken.

I looked up several of her important papers, seeking geometrical diagrams as a way to tell the story of her research pictorially. Though she describes herself as a visual, geometric (and messy!) thinker, I didn't find anything but a lot of algebra (which I would have had to work hard to follow, let alone use to speak to a wide audience, or painstakingly carve in reverse!) But I found an "in" for depicting minimal surfaces and her methods for removing singularities, through Fields Medalist Sir Simon Donaldson's review of her work, including a schematic of "bubbling" and also some of the great science/math communication and articles about her and her work, which were published when she won the Abel Prize.

Born in Clevland to an engineer father Arnold Keskulla and teacher and artist mother Carolyn Windeler Keskulla, her family moved to New Jersey when she was a child. She spent her childhood enjoying nature, playing football and secretly reading science texts, imagining a job where she could avoid people. She started a degree in physics but switched to math at the University of Michigan. In the wake of the Soviet Union's launch of Sputnik the US Congress passed the National Defense Education Act, to encourage more participation in STEM including encouraging women and minorities in those fields. The university added an honours math course in response, which showed her there was more to math than she ever knew and it changed her life. “The structure, elegance and beauty of mathematics struck me immediately, and I lost my heart to it,” she wrote. She switched majors. She chose the Courant Institute of Mathematical Sciences at New York University, for graduate school, avoiding applying to more prestigious schools where she feared the competitive male math culture wouldn't suit her. She married biophysicist Olke C. Uhlenbeck, the son of European intellectuals; his father is well-known physicist George Uhlenbeck. She was quite influenced by her new in-laws. Her parents valued ideas but put an emphasis on earning an income, but her in-laws valued intellectual things and encouraged her pursuit of mathematics. Her husband moved to Harvard and she opted to switch to graduate school at Brandeis University, where she earned her PhD in 1968 with advisor Richard Palais. Palais was exploring the space between analysis (a generalization of calculus) and topology (the study of shapes) and Uhlenbeck enjoyed this in-between world. With Smale, Palais had made advances in the study of harmonic maps, which came out of the calculus of variations and the search for shapes in equilibrium with physical measurements. Uhlenbeck's research built on this.

She found temporary jobs at MIT and Berkeley but was hampered by the classic "two-body problem" for academic spouses (where an couple cannot find two professorships in the same place) and anti-nepotism rules - though she later noted that the institutions which claimed they were precluded from hiring both her and her husband, even in different departments, did not officially have any such anti-nepotism rules on the books. Schools like MIT, Stanford and Princeton which courted her husband, simply declined to hire a woman in math. Her husband generously declined to work at institutions where she could not.

Eventually they both got faculty positions at the University of Illinois at Urbana–Champaign in 1971. But she could not stand life in Urbana, where she was often dismissed as an "academic wife" rather than a professor in her own right. She lacked professional support, did not enjoy teaching, felt undervalued and struggled to find the right research topic for her. But, while there, she met post-doc Jonathan Sacks and they began working whether certain problems converge to harmonic maps; eventually they discovered a sort of "awkward point" or singularity called a bubble where systems cannot converge on a harmonic map. The mathematical concept of a minimal surface minimizes area (or surface tension or energy) the way a soap bubble does in the natural world. They showed there were a finite number of these singularities and that when you rescale a map near them you have "bubbling" as in the diagram in my print. This trick of rescaling was one of her and Sacks' most important contributions.

 She moved to the University of Illinois at Chicago in 1976, separating from her husband. In 1983, she moved to the University of Chicago, where there were other women math professors and peers who took her seriously. She received a Sloan Fellowship and finally knew she could support herself and her research. She learned the value of a professional support network and realized that isolating herself was hurting her and her career. Her work with Sacks was foundational to the development of the new mathematical field of geometrical analysis. This bubbling phenomenon was found in many different sorts of mathematical physics. She took her intuition and techniques honed working on minimal surfaces and began ground-breaking work in gauge theory and the nature of exotic n-spaces, a means of connecting observations at different places that comes up in the quantum mechanical world of fundamental forces, building on the work of mathematical physicists like Weyl, Yang and Mills. With C.H. Taubes, she analyzed Yang-Mills equations in four dimensions; she proved her removable singularities theorem, showing that bubbling cannot occur around isolated points, so if a finite-energy solution exists to the Yang-Mills equations near a point, the solution will extend smoothly to the point. Simon Donaldson's extension of this research won him the prestigious Fields Medal for mathematics in 1986. Uhlenberck won a MacArthur Prize Fellowship or "genius grant" (1983-1988) which made her feel, "obliged to become more ambitious.”

She married mathematician Robert F. Williams, then in 1988, moved to the University of Austin as the Sid W. Richardson Foundation Regents Chairholder and won the Noether Lecture award from the Association for Women in Mathematics. In 1990, she was only the second woman in math to give the plenary lecture at the International Congress of Mathematicians in Kyoto, after none other than mathematical giant Emmy Noether. She founded the Park City Mathematics institute and with Chuu-Lian Terng she co-founded the IAS Women and Mathematics (WAM) program to recruit and retain more women in math, encouraging collaboration and mentorship at all stages of their careers, a complete turn-around from the isolation she sought at the beginning of her career and her avoidance of her fellow women in math because “It was self-evident that you wouldn't get ahead in mathematics if you hung around with women.” Together, they've created a network of nearly 1500 women mathematicians. She realized that one needs role models - not examples of perfection, but people who make errors but pick themselves back up. When asked if she had a role model, she cited beloved chef and TV presenter Julia Child! "She had these fantastic television programs, and she was a real person. She could pick the turkey up off the floor and serve it," Uhlenbeck said. She founded the Distinguished Women in Mathematics Lecture Series at the University of Texas at Austin. Uhlenbeck won the National Medal of Science in 2001 and the 2007 Steele Prize for a Seminal Contribution to Mathematical Research from the American Mathematical Society. Granted yearly by the King of Norway, rather like a math equivalent to the Nobel, the Abel Prize includes a $700,000 award, and recognizes a mathematician’s entire career. Uhlenbeck became the first (and so far only) woman to win the Abel Prize in 2019.  She donated half the funds to organizations encouraging underrepresented (that is, traditionally excluded) minorities in mathematics. She further donated to environmental organizations and the National Academy of Science. She is now an emeritus professor at Austin, as well as a visiting associate at the Institute for Advanced Study and senior research scholar at Princeton University.

Like so many of my subjects, I've found she also loves art and began drawing more than a decade ago, mostly landscapes. She notes, “I discovered the fascinating fact that the problem of scale occurs both in mathematics and in drawing.” In drawing you want to capture the full forest as well as the details of individual plants, just as you want to capture all scales in math. “The hardest part with both is fitting the two scales together. You need the right tools.” Uhlenbeck has provided the world of mathematics and physics with so many of just the right tools.

References

Donaldson, S.. “Karen Uhlenbeck and the Calculus of Variations.” Notices of the American Mathematical Society 66 (2019): 1. DOI:10.1090/noti1806

Sioban Roberts, "In Bubbles, Karen Uhlenbeck Sees a Mathematical Universe," The New York Times, April 8, 2019

Karen Uhlenbeck, Wikipedia, accessed July 2021.

Rachel Crowell, "Karen Uhlenbeck Becomes First Woman To Win Abel Prize For Mathematics," Forbes, March 20, 2019

Dale DeBakcsy, How Mathematical Lone Wolf Karen Uhlenbeck Found Her Pack, Women You Should Know, November 29, 2017.

Karen Uhlenbeck, Karen Uhlenbeck on Being the First Woman to Receive the Abel Prize, remarks made at reception at the Institute for Advanced Study on March 19, 2019.

Karen Uhlenbeck, Coming to grips with success: a profile of Karen Uhlenbeck, Celebratio Mathematica, 1996

Jessica Atlee, Crossing Fields: Karen Uhlenbeck’s pioneering work marries math with physics, Symmetry Magazine, August 15, 2019.

Erica Karreich, Karen Uhlenbeck, Uniter of Geometry and Analysis, Wins Abel Prize, Quanta Magazine, March 19, 2019

Marianne Freiberger, The Abel Prize 2019, Plus magazine, University of Cambridge, March 19, 2019.

Thursday, April 1, 2021

Chomsky Hierarchies, where math meets linguistics and computer language

 

Linocut 'Chomsky Hierarchy' by Ele Willoughby, 2021


This is one of the #mathyear prompts I had previously skipped. Chomsky hierarchies are the place math meets computer language and linguistics, and is something I have never studied, so I didn't have a good idea how to protray them. This year, I'm trying to do all the prompts I previously skipped, and I had a visiual idea.

This is a linocut portrait of linguist Noam Chomsky with a Venn diagram illustrating  the Chomsky hierarchy (or Chomsky-Schützenberger hierarchy) for formal grammars in formal language theory. In 1956, Noam Chomsky described the hierarchy of formal grammars (how to form strings from a language's alphabet that are valid according to the language's syntax). These ideas and hierarchy are pertinent for applied mathematics, theoretical computer science, theoretical linguistics and other areas.

He categoried 4 types of grammars, shown in the Venn diagram behind his portrait. Type 0, in pale yellow, contains recursively enumerable grammars, such that there exists a Turing machine which will enumerate all valid strings of the language. Type 1, in umber, contains context-sensitive grammars, are recognized by non-deterministic linear-bounded automata. Type 2, in orange, are context-free grammars, recognized by non-deterministic pushdown automaton. Type 3, in pink, are regular grammars, recognized by finite state automata.