Physics

Climbing the Distance Ladder to the Big Bang: How Astronomers Survey the Universe  –  Dragan Huterer
The furthest objects that astronomers can observe are so distant that their light set out when the Universe was only 800 million years old, and has been traveling to us for about 13 billion years-most of the age of the Universe. Even the Sun’s neighborhood – the local part of our Galaxy, where astronomers have successfully searched for planets around other stars – extends to hundreds of light years. How do we measure the distance to such remote objects? Certainly not in a single step! Astronomers construct the so-called “Distance Ladder,” finding the distance to nearby objects, thus enabling those bodies to be understood and used as probes of yet more distant regions. The first steps in the ladder uses radar ranging to get the distance to the nearby planets and the Sun; and ‘triangulation’ to get the distances to the nearest stars. Those in turn are used to obtain distances to other stars in our Milky Way Galaxy, stars in other galaxies, and out to the furthest reaches of what is observable. This class will explore the steps in this ladder, using lectures, discussions, field trips, demonstrations, and computer laboratory exercises. Students will learn basic computer programming for a project to model the effects of gravity, and they will get hands-on experience of using a small radio telescope to map the the rotation speed of the Milky Way and measure the influence of its dark matter. We will cover concepts involving space, time, and matter that go far beyond the distance ladder, and involve some of the most fascinating mysteries in cosmology and astrophysics: What is it like inside a black hole? What is the Dark Matter? What is the Dark Energy that makes the Universe expand faster and faster? Is there other life in the Universe?

Forensic Physics  –  Ramon Torres-Isea
 A fiber is found at a crime scene. Can we identify what type of fiber it is and can we match it to a suspect’s fiber sample, for example from a piece of clothing? Likewise, someone claims to have valuable ancient Roman coins, a newly-found old master painting, or a Viking map of America predating Columbus’ voyage. Are they authentic or fakes? How can we determine that using some physics-based techniques? (These are real examples the Viking map proved to be a forgery). Also for example, how is a laser-based molecular-probing technique used to stop criminals from trading billions of dollars of counterfeit pharmaceuticals and endangering thousands of lives? These are a few among many examples of experimental physics methods applied to several areas of Forensics. In this session, students will be introduced to these methods and have opportunities to make measurements using molecular, atomic and nuclear forensic techniques. In addition, applications to medical imaging and diagnostics will be introduced. Students will be working at our Intermediate and Advanced Physics Laboratories with the underlying physics for each method presented in detail, followed by demonstrations and laboratory activities, which include the identification of an “unknown” sample. Various crime scenes will challenge students to select and apply one or more of the methods and use their Forensic Physics skills to conduct investigations.

Relativity: A Journey through Warped Space and Time  –  Daniel Mayerson
Einstein forever altered our understanding of the nature of space and time with his theories of relativity. These theories tell us that the speed of light is a universal constant, declare that the fabric of space and time is warped by matter, and demand that matter moves through spacetime by following its curvature. Introduced 100 years ago, these concepts clash mightily with our everyday physical intuition, but are nevertheless cornerstones of modern-day physics. In this course we will explore the exciting world of relativity (both the special and general theories). After briefly reviewing classical mechanics (Newton’s laws), we will use thought experiments to understand the ideas behind relativity and see how they are actually ultimately simpler and more natural than classical mechanics. Along the way we will encounter strange paradoxes that push the limits of our understanding and learn powerful mathematics that will allow us to quantify our relativistic understanding of the universe. Using our new knowledge, we will delve into black holes, learn how GPS systems work, and debate the possibility of time machines and wormholes. Prerequisites: basic concepts in geometry (e.g. coordinates, distance formulae) and working knowledge of elementary calculus (e.g. what a derivative is and how to take one). We will introduce some multivariable calculus (e.g. partial differentiation) and integration techniques, so prior knowledge of those is a bonus. An open, curious and interested mind is absolutely necessary; you must be willing to think deeply about physics and the nature of our universe!

Roller Coaster Physics  –  David Winn
What are the underlying principles that make roller coasters run? By studying the dynamics of roller coasters and other amusement park rides in the context of Newtonian physics and human physiology, we will begin to understand these complex structures. Students first review Newtonian mechanics, a = f/m in particular, with some hands-on experiments using air-tables. This will then be followed by digital-video analysis of motion of some real-life objects (humans, cars, and toy rockets) and student-devised roller coaster models. Then, a field trip to Cedar Point Amusement Park (outside of the regularly scheduled weekend trip) where students, riding roller coasters and other rides, will provide real data for analysis back at UM. Students will carry portable data loggers and 3-axis accelerometers to provide on-site, and later off-site, analysis of the motion and especially, the “g-forces” experienced. The information collected will then be analyzed in terms of human evolution and physiology; we shall see why these limit the designs of rides. In addition to exploring the physics of roller coasters, cutting-edge topics in physics will be introduced: high energy physics, nuclear astrophysics, condensed-matter theory, biophysics and medical physics. Students will then have a chance to see the physics in action by touring some of UM’s research facilities. Students will have the opportunity to see scientists doing research at the Solid State Electronics Laboratory, the Michigan Ion Beam Laboratory, and the Center for Ultrafast Optical Science. By the end of the two-week session, students will gain insight and understanding in physics and take home the knowledge that physics is an exciting, real-life science that involves the objects and motions surrounding us on a daily basis.

The Physics of Magic and the Magic of Physics  –  Georg Raithel
Rabbits that vanish; objects that float in air defying gravity; a tiger that disappears and then reappears elsewhere; mind reading, telepathy and x-ray vision; objects that penetrate solid glass; steel rings that pass through each other: these are some of the amazing tricks of magic and magicians. Yet even more amazing phenomena are found in nature and the world of physics and physicists: matter than can vanish and reappear as energy and vice-versa; subatomic particles that can penetrate steel; realistic 3-D holographic illusions; objects that change their dimensions and clocks that speed up or slow down as they move (relativity); collapsed stars that trap their own light (black holes); x-rays and lasers; fluids that flow uphill (liquid helium); materials without electrical resistance (superconductors.) In this class students will first study the underlying physics of some classical magic tricks and learn to perform several of these (and create new ones.) The “magic” of corresponding (and real) physical phenomena will then be introduced and studied with hands-on, minds-on experiments. Finally, we will visit a number of research laboratories where students can meet some of the “magicians” of physics – physics students and faculty – and observe experiments at the forefront of physics research.