Proving Einstein:

Amuneal’s Technical Products staff recently visited the basement laboratories of Stanford University’s Varian Physics Building to see one of our more recent magnetic shielding challenges which is being used in Stanford’s Atom Interferometric Test of the Equivalence Principle. Stanford physicists are attempting to measure the differential gravitational acceleration of two isotopes of Rubidium to an accuracy of 10-15 g.

For those of us who aren’t physicists, think back to learning about Galileo dropping spheres off the Leaning Tower of Pisa: The research team has chosen Rubidium in place of the spheres and a 10 meter tall magnetically seamless cylinder fabricated by Amuneal as the tower. To measure at this level of precision, it is necessary to reduce the magnetic field inside the shielding to a uniform field over the majority of the 10 meter length of the cylinder. During Stanford’s research, no data was found to suggest anyone has experimented with a seamless shield of this aspect ratio. The final design is a three layer, 10 meter tall cylinder with all three layers welded with parent material for magnetic continuity. The research team has been working around the clock setting up the apparatus and expects to begin the experiment in the near future. They anticipate publishing their magnetic shielding findings in addition to the Equivalence Principle research.