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Each of the 11 videos provides case studies of two key scientists and their research. After giving a brief overview of the topic under discussion, each show introduces two different, but related, research programs designed to answer an important question in physics. Through these case studies, viewers will develop a sense of what motivates the research, have an opportunity to look at some of the equipment and techniques scientists use, and learn not only about recent advancements, but also about new questions that need to be answered.

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1. The Basic Building Blocks of Matter
Featured Scientists: Bonnie Fleming and Mark C. Kruse
In the past century, physicists have discovered new constituents of matter—quarks, gluons, neutrinos, and many others. These basic building blocks have been linked together into a theoretical framework, the Standard Model of particle physics, that has been very successful in making predictions that were later confirmed by experiment. Even so, there are hints that the Standard Model is incomplete, and that a deeper theory lies behind it, waiting to be teased into the open. See how scientists are seeking answers to these questions with the latest neutrino experiments and the search for the Higgs boson. View video online
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2. The Fundamental Interactions
Featured Scientists: Srini Rajagopalan and Ayana Arce
A better understanding of the fundamental interactions is a key to physicists' search for a new, underlying theory of the physical world. One starting point is to investigate the microscopic description of forces: electromagnetism, gravity, and the two nuclear forces, strong and weak, with increasingly energetic collisions. The Large Hadron Collider at CERN has not only the highest energy yet achieved in a particle accelerator, but also the highest luminosity—with events measured in millions of collisions per second. This presents a challenge for physicists to capture only the most interesting events and to find reliable ways to analyze these to reveal interactions that have never been seen before. View video online
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3. Gravity
Featured Scientists: Eric Adelberger and Nergis Mavalvala
The study of gravity has played a central role in the history of science—from Galileo and Newton to Einstein's twentieth century theory of general relativity. Yet, in spite of five centuries of study, many aspects of gravity remain a mystery. How can gravity, which in many ways is the dominant force in the universe, be at the same time, by far, the weakest of the four known forces in nature? See how physicists are approaching this question through two topics of intense research in gravitational physics today: short-scale measurements of gravity's inverse-square law, and the search for ripples in space-time known as gravitational waves. View video online
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4. String Theory and Extra Dimensions
Featured Scientists: S.-H. Henry Tye and Juan Maldacena
In the 20th century, twin breakthroughs—quantum mechanics and general relativity—provided fresh insight into phenomena at the sub-atomic and cosmological scales, respectively. Yet physicists are still struggling to develop a consistent theory that bridges quantum mechanics and gravity. One approach to "quantum gravity" is string theory: a mathematical description of particles and forces at scales 1031 times smaller than a proton. String theory attempts to link particle physics, the forces of nature, and the earliest moments of the universe into a fresh theoretical framework. Hard evidence remains elusive, but theorists are applying string theory to important problems, such as explaining the exponential growth of the early universe and the paradoxes introduced to physics by the existence of black holes. View video online
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5. The Quantum World
Featured Scientists: Martin Zwierlein and David J. Wineland
We are in a new quantum age in which the abstract concepts of the quantum revolution have become concrete thanks to rapid advances in controlling and manipulating atoms, molecules, and light. Practical applications, from lasers and atomic clocks to telecommunications and mp3 players, are only part of the story. Find out how laser cooling and trapping enables new laboratory experiments as models for disparate systems, giving new insight to phenomena at extreme scales from the atomic nucleus to neutron stars. Cooling and trapping atoms is also key to super-precise clocks—new tools that are being used to search for subtle changes over time in the fundamental constants of nature. View video online
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6. Macroscopic Quantum Mechanics
Featured Scientists: Jenny Hoffman and Deborah S. Jin
Quantum mechanics provides a useful description of nature at the atomic and subatomic scale, but it also manifests itself in phenomena at macroscopic scales, including lasers, clouds of ultra-cold atoms, superfluids, and superconductivity. Among these phenomena, the recent discovery of new kinds of high-temperature superconducting materials holds the promise of many practical applications—but there is still no theory about how these materials work. See how researchers are approaching this problem from two different directions: a "top-down" approach, closely examining the materials themselves, and a "bottom-up" approach, looking at model systems that mimic the quantum interactions of the superconducting electrons inside the materials. View video online
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7. Manipulating Light
Featured Scientists: Paul Kwiat and Lene Hau
Tools of quantum mechanics are opening new possibilities for controlling and manipulating light. Paul Kwiat is creating photons "to order" by carefully manipulating their quantum properties. In 2001, Lene Vestergaard Hau stopped a pulse of light in a cloud of atoms and then released it, along with the information it contained. Explore not only how light interacts with matter at the quantum level, but also learn more about the concepts of entanglement and action at a distance, and consider how experiments with storing information in matter are building the groundwork for a new technology: quantum computers. View video online
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8. Emergent Behavior in Quantum Matter
Featured Scientists: Paul Chaikin and Piers Coleman
Reductionism—breaking things into their component parts to study how they work—is an effective tool in physics. But many real-world challenges resist this approach. All too often, large scale behavior emerges in ways that are difficult to predict from the behavior of individual components. When the computational requirements are too massive or the theories that govern the component parts are inadequate, many complex systems have yielded to the physics of emergence, which seeks organizing principles at the system level. Find out how many different phenomena—superconductors, hydrodynamics, and even the formation of structure in the universe—are all fruitful areas where the physics of emergence is leading to new understanding. View video online
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9. Biophysics
Featured Scientists: Vinothan N. Manoharan and Harald Paganetti
Scientists are developing broad, rapidly increasing connections between biology and physics which provide fresh insight into biological problems such as evolution, the assembly of proteins, neural networks, and possibly the origin of life itself. See how basic reserach in this rapidly-emerging field is helping scientists better understand how viruses self-assemble, and may eventually lead to new cures for disease. Clinical applications available today include cancer therapy, which uses the technology developed for earlier generations of particle accelerators to create precisely-controlled beams of high-energy protons that can attack tumors with minimal damage to surrounding tissues. View video online
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10. Dark Matter
Featured Scientists: Doug Finkbeiner and Rick Gaitskell
Since Swiss astrophysicist Fritz Zwicky first inferred its existence in 1933, dark matter has remained one of the greatest unsolved mysteries in cosmology. Invisible to telescopes, dark matter was detected through its effects on visible matter. Astronomical measurements have shown that dark matter is three-fourths of all matter, but at present no one has yet directly observed a dark matter particle. See how astrophysicists are seeking evidence for dark matter at the center of the Milky Way galaxy and how a new detector almost a mile underground will look for dark matter particles in the laboratory. View video online
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11. Dark Energy
Featured Scientists: Robert P. Kirshner and David Spergel
Cosmologists have known that the universe is expanding in all directions since early in the 1920s. Later in the century, they used new instruments to examine the question again. They assumed that—due to gravity—the rate of expansion of the universe today would be slower than the rate in the past. Instead, measurements showed that the cosmic expansion has been speeding up. The expansion is attributed to "dark energy," a kind of springiness of empty space itself. Today's astronomical measurements show that dark energy makes up about 70% of the total mass-energy in the universe. This deep mystery lies right at the heart of understanding gravity. See how observations that measure the history of cosmic expansion more precisely, along with a more detailed look at the cosmic microwave background, are providing new clues about the nature of dark energy. View video online