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Spring 2024

Saturday February 24 — "The Secret Language of Nature's Tiny Communicators"

• Presented by: Professor Orit Peleg, Department of Physics and Computer Science, University of ����ֱ�� Boulder
• 2:30 p.m.
• Abstract: Imagine a world where communication doesn't depend on words, but on flashes of light, scents, and movement. In the extraordinary world of insects, this is a daily reality. This talk will take you on a journey into the secret lives of fireflies and bees, exploring how they convey information through visual and chemical signals. Drawing on concepts from physics, mathematics, and computer science, we will uncover the universal rules that insects obey to make their communication efficient and effective. We'll investigate fireflies, whose twinkling lights allow them to "speak" over vast distances, and bees, who use scents to tell the story of their queen's location. Through a mix of real-world observation and innovative computational techniques, we'll unravel the mysteries behind these intriguing forms of dialogue.

Saturday March 16 — "Quantum computing: what is it and how far along are we?"

• Presented by: Daniel Slichter, NIST, University of ����ֱ�� Boulder
• 2:30 p.m.
• Abstract: Imagine if the act of looking at an object caused it to move – or imagine you had a pair of dice that always rolled doubles, but of different numbers each roll. These counterintuitive phenomena are commonplace in the realm of quantum mechanics, which describes systems that are generally very small, very cold, and/or very isolated from the rest of the world. Over the past 40 years, scientists have developed ideas for harnessing the strange features of quantum mechanics to build “quantum computers”, machines where information storage and computation is carried out by objects that behave quantum mechanically. A large-scale quantum computer would in principle be able to perform certain kinds of computations that would be impossible on even the largest classical (i.e. non-quantum) supercomputers. I will describe some of the basics of quantum mechanics and quantum computing, including why it is so technically challenging to build a “useful” large-scale quantum computer. I will also give some perspective on where things stand in the quest for quantum computers that will provide an advantage over existing computing technology.

**Postponed to Fall 2024** Saturday April 27 — "Rare earth and other critical elements - their physics, resources, and geopolitics"

• Presented by: Professor Markus Raschke, University of ����ֱ�� Boulder
• 2:30 p.m.
• PLEASE NOTE: This lecture has been postponed due to unforseen scheduling issues.
• Abstract: The rare earth elements, hidden at the bottom of the periodic table and long neglected, have risen to prominence at the end of the 20th century. Their unique electronic configuration form the basis for a variety of lasers, photonic applications, strong and exotic magnetism, defining many modern technologies. I will tell a story connecting from the basic science of the geology of ����ֱ�� and rare earth and other rare element mineralogy, to our technological and societal dependence and questions of strategic element security. 

Fall 2023 

Saturday October 28 — "Enabling Innovation with Measurement Science"

• Presented by: Dr. Marla L. Dowell, Director, NIST Boulder Laboratory
• 2:30 p.m.
• Abstract: From the communications and electronic health records to atomic clocks, advanced nanomaterials and computer chips, innumerable products and services rely in some way on technology, measurement and standards provided by the National Institute of Standards and Technology. What do semiconductor manufacturing, welding, and photodynamic therapy have in common? They all rely on laser measurements for their underlying processes to be effective. We’ll discuss the role of lasers and laser measurements in these different applications. We’ll touch on why a career in physics is a great choice for curious people who like solving technical problems that impact their daily lives.

Saturday November 18 — "The C-PhLARE Project: One Thousand Students vs. the Paradox of the Sun"

• Presented by: Professor Colin G. West, University of ����ֱ�� Boulder
• 2:30 p.m.
• Abstract: It is likely both intuitive and familiar that, as you walk further from a campfire, you feel less of its heat. And yet the same is not true for the great fireball in the sky: our sun. In fact, the Sun’s corona is millions of kelvin hotter than its photosphere, despite being much further away from the center of the star. From 2020 through 2021 a team of over a thousand undergraduate students at ����ֱ�� Boulder painstakingly analyzed the X-ray emissions of hundreds of individual solar flares in search of evidence to help resolve this mystery. We'll discuss their findings and conclusions, as well as the novel circumstances that led to this unique collaboration, and the publication of a paper with the most co-authors in the history of The Astrophysical Journal.

**Cancelled** Saturday December 2 — "The Secret Language of Nature's Tiny Communicators"

• Presented by: Professor Orit Peleg, Department of Physics and Computer Science, University of ����ֱ�� Boulder
• 2:30 p.m.
• Abstract: Imagine a world where communication doesn't depend on words, but on flashes of light, scents, and movement. In the extraordinary world of insects, this is a daily reality. This talk will take you on a journey into the secret lives of fireflies and bees, exploring how they convey information through visual and chemical signals. Drawing on concepts from physics, mathematics, and computer science, we will uncover the universal rules that insects obey to make their communication efficient and effective. We'll investigate fireflies, whose twinkling lights allow them to "speak" over vast distances, and bees, who use scents to tell the story of their queen's location. Through a mix of real-world observation and innovative computational techniques, we'll unravel the mysteries behind these intriguing forms of dialogue.

Fall 2023

Saturday February 25 — "The Big Bang: The Universe, Past, Present and Future"

• Presented by: Professor Paul Beale, Department of Physics, University of ����ֱ�� Boulder
• 2:30 p.m.
• Abstract: Science is a human endeavor. The discovery that the universe began abruptly 13.8 billion years ago is one of the great scientific stories of the last century. We will explore the empirical evidence of the Big Bang, the scientific framework that allows us to infer with considerable certainty what happened in the first moments of the universe, the scientists that solved the puzzle of how that led to our existence, and what the future holds.

Saturday March 11 — "Black Holes: a Virtual Voyage"

• Presented by: Andrew Hamilton, Professor, Department of Astrophysical and Planetary Sciences and Physics, University of ����ֱ�� Boulder
• 2:30 p.m.
• Abstract: Black holes have become famous in both science and pop culture for their unique gravitational power. But what really happens in the mysterious interior of a black hole? Join Professor Hamilton on a virtual voyage inside a black hole using a real-time, interactive, general relativistic Black Hole Flight Simulator.

Saturday April 15 — "An Airline Crash Investigation: Physics vs Lawyers"

• Presented by: Michael Dubson, Department of Physics, University of ����ֱ�� Boulder
• 2:30 p.m.
• Abstract: On July 26, 2002, FedEx flight 1478 crashed on landing at the Tallahassee Regional airport. The crew of three survived, but were fired by FedEx. The pilots contested their firing and I was hired to investigate. I was able to show experimentally that the runway lighting very likely failed due to condensation on the projection system. Yet the pilots' lawyers decided that my testimony would not help their clients, and my results were not presented. I will present the physics and sociology of this curious case.

2020-2021 Schedule

Saturday February 13 — "Can you Count to One Quadrillion in a Second?"

• Presented by: Professor Scott Diddams, NIST and Department of Physics, University of ����ֱ�� Boulder
• Webinar at 1:30 PM
• Abstract: Metrology is the framework behind modern science and technology. For most of us, our first experience with metrology might have been counting fingers and toes. But how do you measure the oscillations of a beam of light—the fastest thing in the universe? This talk will tell you about new metrology tools that are used to count the cycles of a wave of light and how that is being used to build ultraprecise optical atomic clocks. Interestingly, the same light measurement tools are also being applied to quantify the composition of the air we breathe and find exoplanets around nearby stars.

Saturday March 13 — "The Field of Medical Physics: A Primer"

• Presented by: Professor Moyed Miften, Professor and Chief Physicist, Deptartment of Radiation Oncology, University of ����ֱ�� School of Medicine
• Webinar at 1:30 PM
• Abstract: Medical Physics is a professional and academic field that specializes in the application of concepts and methods of physics to the diagnosis and treatment of human disease.  The role of a medical physicist is to bridge physics and medicine and work as a part of the medical team.  Medical Physics has three major disciplines: Radiation Oncology Physics, Diagnostic Imaging Physics, and Medical Nuclear Physics.  Working in these three fields are rewarding as the medical physicist applies the principles of physics to medicine in order to solve challenging problems, develops new technologies for medical applications and patient care advancements, and actively contributes to the care of patients in the clinic.  In this presentation, we will review the medical physics disciplines in medicine and their role in patient care, discuss the medical physicist areas of responsibility, present medical physics career pathways (including medical physics graduate program requirements), and discuss medical physics professional credentialing.

Saturday April 17 — "Atomic Clocks: The Greatest Rulers of Time"

• Presented by: Professor Ana Maria Rey, JILA, NIST, and Department of Physics, University of ����ֱ�� Boulder
• Webinar at 1:30 PM
• Abstract: The best clock in the world has no hands, no pendulum, no face or digital display. It is made of ultra-cold Strontium atoms trapped in crystals of light. The clock is so precise that, had it begun ticking when Earth formed billions of years ago, it would not yet have gained or lost a second. These ultraprecise atomic clocks not only can serve as the state-of-the-art timekeepers, but also they could help us unveil the mysteries of the quantum world, which is ruled by the bizarre concept of entanglement or “spooky action at a distance”. In fact, the new generation of atomic clocks are paving the ground for the construction of quantum computers with computational powers beyond that of any imaginable classical machine. A quantum computer should be able solve otherwise intractable problems, with far-reaching applications to cryptology, material design and fundamental physical sciences. Can we make the clock even better? Regardless of their impressive precision and accuracy, current atomic clocks still operate with independent atoms which are fundamentally fuzzy. Interestingly, this fuzziness could be reduced if we entangle them. So atomic clocks are a win-win business, not only the current generation of clocks will help us to better understand the quantum world, but the gained understanding will in turn allow us to build the most incredible quantum rulers of time in the future.

September 28 — "Rocky Mountain High: The Physics of Baseball at Elevation"

• Presented by: Professor John Bohn
• Location: DUAN G1B30
• Abstract: From the beginning, Coors Field has been tagged as a hitter’s ballpark, with home runs flying out at an incredible rate and pitchers unable to cope.  This is, at least partly, due to the thin air a mile above sea level, and is a result of influences whose physics can be understood.  In this talk I address the physics of baseball in Denver, including the effect the famous Coors Field humidor has had on the game. 

October 19 — "Lunar Exploration: 50 Years After the Historical Apollo 11 Landing"

• Presented by: Professor Shijie Zhong
• Location: DUAN G1B30
• Abstract: This presentation is about the Apollo 11 landing, Apollo mission, and its impact on our understanding of the Moon and Earth-Moon system. Historical events surrounding the Apollo mission and landings will be recounted. Post-Apollo lunar missions by both US and other countries will also be discussed, together with a brief future outlook. 

November 2 — "Harnessing the Power of Plasma to Build the Particle Accelerators of the Future"

• Presented by: Professor Michael Litos
• Location: DUAN G1B20
• Abstract: In order to continue pushing the boundaries of experimental particle physics, particles need to be collided at ever higher energies. This could be accomplished by building even larger accelerators that utilize current technologies, but such an approach may be prohibitively expensive. An alternative approach is to develop new accelerator technologies that can produce a higher energy boost to the particles over each meter of distance. Four decades ago, it was realized that the power of plasma waves could be harnessed to serve this purpose. Since then, plasma wakefield acceleration has become a major field of physics research, and significant progress has been made toward the realization of plasma-powered, high energy physics particle accelerators.

December 7 — "Making Snow - New Insights from Orographic Cloud Seeding"

• Presented by: Professor Katja Friedrich
• Location: DUAN G1B20
• Abstract: Throughout the western U.S., water supplies are primarily fed through the melting of snowpack. Growing populations place higher demands on water while warmer winters and earlier springs reduce its supply. Water managers use seeding orographic clouds in winter as a way to increase snowfall. This talk will provide an overview of the history of cloud seeding, the underlying physical principle, the challenges, and scientific breakthrough to improve experimental design and address the main questions of how much snow can we actually produce.

January 25 — "Living in the Golden Age of Solar Physics"

• Presented by: Professor Maria Kazachenko
• Location: DUAN G1B20
• Abstract: Space weather is largely caused by the activity of our Sun. Invisible yet powerful magnetic fields, created within the Sun, determine when and where the next solar eruption will happen. Large solar storms can put our technological society at risk. In this talk, ����ֱ�� Boulder and National Solar Observatory professor, Maria Kazachenko will discuss how advances in solar telescopes allow scientists to understand the Sun in a lot more detail than ever before.

February 22 — "The Anti-Matter Within Us"

• Presented by: Professor Ed Kinney
• Location: DUAN G1B20
• Abstract: Many people are surprised to learn that the existence of anti-matter is not science fiction, but in fact a very real part of our universe! But what is anti-matter? How can we create it in the laboratory or observe the anti-matter made naturally? How can we tell “regular” matter from anti-matter and what happens when anti-matter and regular matter come together? In this talk we’ll learn about the basics of anti-matter, where you find it and how you make it, and in particular we’ll focus on the anti-matter that exists inside the atoms in our bodies as well as the anti-matter which comes from outer space.

**CANCELLED** March 7 — "From Nanomaterials to NASCAR: Materials at 200 Miles per Hour"

• Presented by: Dr. Diandra Leslie-Pelecky
• Location: DUAN G1B20
• NOTE SPECIAL TIME: 2:00 p.m.

• Abstract: You cannot win a NASCAR race without understanding science. Materials play important roles in improving performance, as well as ensuring safety. On the performance side, NASCAR limits the materials race car scientists and engineers can use to limit ownership costs. 'Exotic metals' are not allowed, so controlling microstructure and nanostructure are important tools. Compacted Graphitic Iron, a cast iron in which magnesium additions produce interlocking microscale graphite reinforcements, makes engine blocks stronger and lighter. NASCAR's new car design employs a composite called Tegris that has 70 percent of the strength of carbon fiber composites at about 10 percent of the cost.

  The most important role of materials in racing is safety. Drivers wear firesuits made of polymers that carbonize (providing thermal protection) and expand (reducing oxygen access) when heated. Catalytic materials originally developed for space-based CO₂ lasers filter air for drivers during races. Although materials help cars go fast, they also help cars slow down safely—important because the kinetic energy of a race car going 180 mph is nine times greater than that of a passenger car going 60 mph. Energy-absorbing foams in the cars and on the tracks control energy dissipation during accidents.

  To say that most NASCAR fans (and there are estimated to be 75 million of them) are passionate about their sport is an understatement. NASCAR fans understand that science and engineering are integral to keeping their drivers safe and helping their teams win. Their passion for racing gives us a great opportunity to share our passion for science with them.

**CANCELLED** March 14 — "Can you Count to One Quadrillion in a Second?"

• Presented by: Professor Scott Diddams
• Location: DUAN G1B20
• Abstract: Metrology is the framework behind modern science and technology. For most of us, our first experience with metrology might have been counting fingers and toes. But how do you measure the oscillations of a beam of light—the fastest thing in the universe? This talk will tell you about new metrology tools that are used to count the cycles of a wave of light and how that is being used to build ultraprecise optical atomic clocks. Interestingly, the same light measurement tools are also being applied to quantify the composition of the air we breathe and find exoplanets around nearby stars.

**CANCELLED** April 11 — "Atomic Clocks: The Greatest Rulers of Time"

• Presented by: Professor Ana Maria Rey
• Location: DUAN G1B20
• Abstract: The best clock in the world has no hands, no pendulum, no face or digital display. It is made of ultra-cold Strontium atoms trapped in crystals of light. The clock is so precise that, had it begun ticking when Earth formed billions of years ago, it would not yet have gained or lost a second. These ultraprecise atomic clocks not only can serve as the state-of-the-art timekeepers, but also they could help us unveil the mysteries of the quantum world, which is ruled by the bizarre concept of entanglement or “spooky action at a distance”. In fact, the new generation of atomic clocks are paving the ground for the construction of quantum computers with computational powers beyond that of any imaginable classical machine. A quantum computer should be able solve otherwise intractable problems, with far-reaching applications to cryptology, material design and fundamental physical sciences. Can we make the clock even better? Regardless of their impressive precision and accuracy, current atomic clocks still operate with independent atoms which are fundamentally fuzzy. Interestingly, this fuzziness could be reduced if we entangle them. So atomic clocks are a win-win business, not only the current generation of clocks will help us to better understand the quantum world, but the gained understanding will in turn allow us to build the most incredible quantum rulers of time in the future.

September 22 — "The Physics of Keeping Secrets: A Look Inside the World of Quantum Encryption"

• Presented by: Professor Colin West
• Abstract: For decades, quantum physics has been talked about as the next big source of technological innovation. Some of the most headline-grabbing applications, such as quantum computers, are still in a state of promising infancy. But there are many other quantum technologies which are much closer to real-world deployment. In this talk, we will explore in particular how quantum physics offers radically new ways to encrypt, store, and share secret information, even as quantum computers themselves threaten to undermine our current secret-keeping capabilities.

October 20 — "The Higgs Boson and Beyond"

• Presented by: Professor Keith Ulmer
• Abstract: In 2012 the CMS and ATLAS experiments at the Large Hadron Collider at CERN made the remarkable discovery of the Higgs Boson. In this talk we'll explore what the Higgs is and how it was discovered, as well as the unique role that it plays in the origin of mass in the universe. The talk will conclude with a discussion of some of the possibilities for what discoveries might be next for these remarkable experiments.

December 1 — "Quantum Glasses"

• Presented by: Professor Rahul Nandkishore
• Abstract: Most quantum systems eventually follow the laws of equilibrium statistical physics  after they come to equilibrium with their environment. Recently, however, some intriguing exceptions –"quantum glass"– have been discovered. Quantum glasses remain quantum even at large scales and long times, and support new quantum phases of matter. In this talk we will explore their properties. 

January 26 — "Powered by the Sun: Turning Light into Electricity with Photovoltaic Cells"

• Presented by: Professor Sean Shaheen
• Abstract: Photovoltaic cells have taken enormous strides recently toward becoming a viable, if not vital, source of renewable energy for our planet. They advantage of photon-electron interactions in semiconductors to generate power that we can use in our everyday lives. Existing cells with solar-to-electric power conversion efficiencies of around 20% are based on silicon and are decreasing in cost rapidly. New cells based on organic and hybrid materials are being developed that have the potential to further decrease costs while increasing the efficiency to 30+%. In this talk I will explain the physics of their operation and provide some intuition as to just how powerful this science can be!

February 23 — "How Can We Explore Galaxy Evolution Using the Same Molecules in Galaxies Found in Diesel Soot on Earth?"

• Presented by: Professor Jason Glenn
• Abstract: Astronomers know a great deal about the properties of galaxies in the present-day Universe. However, fundamental questions remain about how galaxies formed from the smooth plasma in the early Universe. Such as, how and when did the stars in galaxies and the supermassive black holes at the centers form and grow? Professor Glenn will explore the background and open questions, and share the design of the Galaxy Evolution Probe, a NASA infrared space observatory concept, to address these questions. He will discuss what astronomers hope to learn with the Galaxy Evolution Probe, how measurements will be made (including ‘diesel soot’ molecules), and exciting new technology being developed at ����ֱ�� and NASA.

March 16 — "Get out your Popcorn: An Ultrafast Movie"

• Presented by: Professor Markus Raschke
• Abstract: The properties of all materials (including those you use every day in batteries, magnets, touch screens, or solar cells) are defined by the intricate interaction of their elementary building blocks, especially electrons. Electrons hold the atoms together, and are responsible for color, electrical conductivity, and magnetism. However, the motion of electrons occurs both on extremely fast time scales with interactions on equally tiny length scales, making their microscopic investigation extremely difficult. We developed a microscope that can visualize the motion of electrons on their natural time scale of femtoseconds (millionths of a billions of a second) and length scales of nanometers (billionths of a meter). In this talk, we will discuss from the history of microscopy to the development of this new type of microscope to image the most elementary quantum processes for materials discoveries. 

April 27 — "It's Not Just ����ֱ�� Saving Kilowatt-Hours: The Role of Buildings (and Occupants!) in a Truly Efficient Power Grid"

• Presented by: Dr. Lieko Earle
• Abstract: Residential and commercial buildings account for roughly 40% of the nation’s energy use, so they are a big focus area for energy efficiency research. We used to think of a building’s energy efficiency simply in terms of the amount of energy it consumes on an annual basis. The goal was to minimize the energy required to keep the occupants comfortable, by improving the thermal envelope and installing the most efficient equipment for major loads such as HVAC and hot water. Recent advancements in distributed energy resources on the grid (such as renewable generation and storage) are necessitating a shift in how we value electricity: It matters not only how much we use, but when we use it. Research in grid-interactive efficient buildings (GEB) aims to leverage the rapid increase in internet connectivity to make buildings more responsive to electric grid conditions, enabling a greater penetration of renewable resources on the grid while ensuring a more secure, reliable, and affordable energy future for all users.