1A The Short, Rich Life of Positronium
This sculpture references the mutual orbiting and ultimate annihilation of the electron-positron pair that comprise the positronium atom. Measurements of its lifetime and of its spectrum provide important tests of quantum electrodynamics. Finally, the positron’s annihilation with the electron yields high energy gamma rays in the purest known example of Einstein’s famous relationship of mass to energy: E=mc2.
1B Magnetism of the Free Electron: g-2
In 1952, H. R. Crane and his students developed a method to precisely measure the magnetic moment of a free electron. Their results underpinned quantum electrodynamics, a theory that is by far the most accurate and precise that we have in any field of science. The sculpture depicts the path of an electron trapped a solenoidal magnetic field that is slightly stronger at each end than it is at the middle.
1C Veltman’s Nobel Diagram
Martinus Veltman, joined the Michigan physics faculty in 1980 and retired in 1997. He and his student Gerhard ‘tHooft shared the 1999 Nobel Prize for physics for their advances in theoretical physics. The sculpture references Veltman’s use of diagrams in the relevant calculations.
1D Off-Axis Holography
In the early 1960’s, Michigan’s Emmett Leith, Juris Upatnieks and colleagues developed the off-axis method that transformed holography from a laboratory curiosity to a powerful tool of modern technology. The sculpture alludes to the principle of holography in that a visual pattern emerges from the intersection of two periodic arrays.
1E The Beginning of Microwave Spectroscopy
In 1932 David Dennison suggested that the NH3 molecule should exhibit a tunneling (represented in the sculpture) to produce an absorption line at 23 GHz. Neil Williams and his student Claud Cleeton did the experiment, this being the first microwave spectroscopy ever done.
1F Coherent Fiber Optics
In 1956, Physics professor C. Wilbur Peters and his undergraduate student Lawrence Curtiss together with Basil Herschowitz, a fellow in the medical school, were the first to develop a practical method to make a fiber optic bundle capable of transmitting a useful image in a clinical situation. They achieved optical isolation between fibers, (shown in the sculpture) and so made possible the modern methods of arthroscopic surgery and diagnostic endoscopy.
1G Insiders-Outsiders
Three Möbius bands, stacked, to remind the viewer that outsiders can find their way inside without crossing sharp edges. Installed in the offices of the minority-emphasis Comprehensive Studies Progam, Angell Hall, University of Michigan,