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National Security Science Computing Issue PHOTOBOMB t Daniil Svyatsky of the Applied Mathematics and Plasma Physics group at Los Alamos National Laboratory demonstrates the power of Amanzi–ATS, a computer code that’s used to simulate environmental systems. Shown here, a 3D Amanzi–ATS simulation models fractured porous material, such as rock, and the flow of chemicals through that material. Los Alamos scientists are particularly interested in the code’s national security applications, such as studying how gases from an underground nuclear test flow through the earth. In 2020, Amanzi–ATS won an R&D 100 award—an “Oscar of Innovation.” H 16 IN THIS ISSUE 2 Letters: The computing issue Los Alamos has led the way in the development and use of computer simulations to understand the world around us. 4 Abstracts: Notes and news from around the Lab Scientists detect deceptive deepfake videos, superbugs get squashed with a new antiseptic, social media 416 is used to inform policy decisions, and more. 68 FEATURES 16 Computing on the mesa Since the Manhattan Project, scientists’ need to process, store, and visualize large quantities of numerical data to simulate physical phenomena has kept Los Alamos on the front lines of computing. 32 Cool computing Warm water 34 36 + mixed with a little detergent keeps supercomputers from overheating. 34 The bizarre and promising 44 54 + world of quantum computing Quantum computers derive their extreme speeds from mysterious properties of quantum physics. 36 “We thank Miss Mary Tsingou” A half-century after being mentioned in the footnote of a seminal physics paper, one of the Laboratory’s first computer programmers gets the recognition she deserves. 44 Computing for a cure As part of its mission to solve national security challenges, Los Alamos scientists are using computers to 59 fight the coronavirus pandemic. 54 Analysis: The architect of stockpile stewardship Victor Reis shares his experiences at the intersection of policy and science. 56 56 Being essential: Math and music run in this family Together, siblings Joel and Candace Vargas write and record songs. 58 Accolades: The distinguished About the cover: Using a computational fluid achievements of Los Alamos dynamics code, a supercomputer can produce a model employees that simulates turbulence when materials (such as gases, liquids, or metals) mix and change states. For 59 Looking back: 26 years ago example, when the cold water of Antarctica mixes with the warm Gulf Stream, the interaction produces Remembering Navajo nuclear turbulence, which is seen as vortices and curves and physicist Fred Begay during National offers valuable information about material interactions. American Indian Heritage Month. WINTER 2020 › 1 ‹ LETTERS THE COMPUTING ISSUE MASTHEAD EDITOR Whitney Spivey Los Alamos National Laboratory has led the way in developing and ART DIRECTOR Brenda Fleming using computer simulations to understand the world around us. STORY EDITOR Eileen Patterson COPY EDITOR Sheila Molony WRITERS Arthur Bishop, complex situations, such as the need Katharine Coggeshall, Virginia Grant, to avert an Earth-asteroid collision. Nicholas Lewis, Cristina Olds, At Los Alamos, computing has J. Weston Phippen, Octavio Ramos, been integral to our work since the Brye Steeves Manhattan Project (see p. 16). In the ILLUSTRATOR Paul Ziomek early days, human computers—often PHOTOGRAPHERS Jathan Campbell, the wives of scientists—performed Daniel Owen, Kevin Roark, calculations to support the Kevin Sutton development of the world’s first atomic EDITORIAL ADVISORS Kirk Otterson, bombs. Over time, human computers Michael Port, John Scott were phased out and replaced with mechanical and then electronic National Security Science highlights work in the weapons and other computers, such as the MANIAC (see national security programs at Los Alamos p. 23). Today, we use supercomputers National Laboratory. NSS is unclassified that perform billions of calculations and supported by the Lab’s Office of National Security and International per second. Studies. Current and archived issues of the magazine are available at In the Laboratory’s Weapons lanl.gov/magazine. Unless otherwise JOHN SCOTT programs, scientists use this credited, all images in the magazine DIRECTOR, OFFICE OF NATIONAL computing power to simulate nuclear belong to Los Alamos National Laboratory. SECURITY AND INTERNATIONAL STUDIES explosions. The extreme conditions To subscribe, email [email protected], or leading up to a nuclear explosion call 505-667-4106. The world is made up of many physical cause solid materials to flow and LA-UR-20-28223 systems—from natural systems, such as display instabilities and turbulence Los Alamos National Laboratory, an affirmative action/equal opportunity the formation of galaxies, to manmade characteristic of fluids. Understanding employer, is operated by Triad National systems, such as the detonation of the complex processes of instability Security, LLC, for the National Nuclear a nuclear weapon. The experiments and turbulence allows us to simulate Security Administration for the U.S. Department of Energy under contract scientists conduct to understand with better accuracy the performance 89233218CNA000001. physical systems provide us with of America’s nuclear deterrent. knowledge essential for protecting the The Laboratory’s supercomputers national interest, preventing disasters, are leveraged for non-weapons work, NSS STAFF SPOTLIGHT finding cures for disease, and creating t too. As you’ll read on p. 44, our innovative, new technologies. supercomputers are being used in But what do scientists do when a the fight against COVID-19. We also physical system is too small, too large, use our supercomputers to better too fast, too costly, too dangerous, understand biology, climate, space, or otherwise inaccessible for an and just about any other area of study experiment in a laboratory? Since one can think of. the 1940s, scientists have increasingly As we begin to say goodbye to Trinity relied on computer simulations (currently the world’s seventh-fastest to understand phenomena that supercomputer, which is approaching cannot be experienced directly. the end of its useful life) and Computer simulations let scientists make plans to install its successor, conduct virtual experiments using Crossroads, we will continue to lead mathematical models—programs the world in computing power and that attempt to replicate the natural drive the computing industry to In September 2020, story editor Eileen Patterson retired from behavior of an object or force. Virtual develop ever-faster and more powerful the Laboratory after 28 years. experiments open up new realms of computers. With our nation’s best Here, two-year-old Eileen (left) research; for example, scientists can see interests at heart, we will continue and her sister, Louise, kneel a solar system evolve over eons. Virtual to use computers to help us simulate by their father, physicist and engineer Frank Tallmadge, experiments also help us plan for what we can only imagine. H shortly after he came to the Lab in 1948. › 2 ‹ WINTER 2020 A NOTE OF CONFIDENCE LISTEN UP President Roosevelt lauds American science. National Security Science magazine now has a podcast! Less than a year into the Manhattan Project—the U.S. government’s top-secret project to create the world’s first atomic bomb to help The National Security Science podcast, a end World War II—President Franklin Roosevelt wrote a letter of spin-off of this magazine, brings you stories confidence and appreciation to Robert Oppenheimer, the project’s from the Weapons programs at Los Alamos scientific director. Working at a secret laboratory in Los Alamos, National Laboratory—stories that show how New Mexico, Oppenheimer’s team of scientists and engineers innovative science and engineering are key would go on to detonate an experimental atomic device in July 1945 to keeping America safe. Or, as we like to say, and partner with the military to drop two atomic bombs on Japan better science equals in August 1945. Roosevelt would have died by this time, but his better security. confidence was justified, and his words remain true today: “Whatever the enemy may be planning, American science will be equal to The first three the challenge.” H episodes highlight different branches of our nuclear triad—the land, air, and sea-based components of America’s nuclear deterrent. Listen and subscribe anywhere you download podcasts. H EPISODE 1 “A wealth of stealth” is written and read by Lieutenant Colonel Geoffrey Steeves, a senior Los Alamos Air Force Fellow and B-2 bomber pilot. Most of the nuclear weapons a B-2 can carry were designed at Los Alamos. EPISODE 2 “A moment of glory” features Los Alamos Air Force Fellow Major Nicholas Edwards. As part of the Air Force’s 576th Test Squadron, Edwards test-launched unarmed Minuteman III intercontinental ballistic missiles. EPISODE 3 “Salt life” is written and read by Navy veteran and former Los Alamos employee Mark Levin. Learn what it’s like to serve on board an Ohio- class submarine that has the ability to launch Los Alamos– designed nuclear weapons. WINTER 2020 › 3 ‹ ABSTRACTS INFOGRAPHIC t THE INTERSECTION Science and culture converge in Northern New Mexico—and beyond. DELIVERY SYSTEM t QUALIFIED FOR DELIVERY The F-15E fighter jet is equipped to carry the updated B61 gravity bomb. A mock version of the B61-12 gravity bomb, designed by Los Alamos and Sandia national laboratories, has been successfully tested on the F-15E, making the aircraft the first fighter jet to be officially compatible with this nuclear weapon. Two test flights were flown in March at the Tonopah Test Range in Nevada. During one flight, a mock weapon was released at about 1,000 feet and nearly the speed of sound, while a higher-altitude test occurred at around 25,000 feet. Both test drops hit the target. These flight tests are one important milestone in the overall weapon certification program. With the first production unit scheduled for completion in November 2021, the B61-12 will ultimately replace the B61-3, -4, -7, and -10 nuclear gravity bomb variants.
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