|Fig.3 Revisionist History and String Theory and the Real World|
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|The newly-installed Alpha Magnetic Spectrometer-2 (AMS)|
Excerpt from "Alpha Magnetic Spectrometer - A Physics Experiment on the International Space Station" by Dr. Sam Ting: The Alpha Magnetic Spectrometer (AMS-02) is a state-of-the-art particle physics detector constructed, tested and operated by an international team composed of 60 institutes from 16 countries and organized under United States Department of Energy (DOE) sponsorship. The AMS-02 will use the unique environment of space to advance knowledge of the universe and lead to the understanding of the universe's origin by searching for antimatter, dark matter and measuring cosmic rays.
Experimental evidence indicates that our Galaxy is made of matter; however, there are more than 100 hundred million galaxies in the universe and the Big Bang theory of the origin of the universe requires equal amounts of matter and antimatter. Theories that explain this apparent asymmetry violate other measurements. Whether or not there is significant antimatter is one of the fundamental questions of the origin and nature of the universe. Any observations of an antihelium nucleus would provide evidence for the existence of antimatter. In 1999, AMS-01 established a new upper limit of 10-6 for the antihelium/helium flux ratio in the universe. AMS-02 will search with a sensitivity of 10-9, an improvement of three orders of magnitude, sufficient to reach the edge of the expanding universe and resolve the issue definitively.
The visible matter in the universe (stars) adds up to less than 5 percent of the total mass that is known to exist from many other observations. The other 95 percent is dark, either dark matter (which is estimated at 20 percent of the universe by weight or dark energy, which makes up the balance). The exact nature of both still is unknown. One of the leading candidates for dark matter is the neutralino. If neutralinos exist, they should be colliding with each other and giving off an excess of charged particles that can be detected by AMS-02. Any peaks in the background positron, anti-proton, or gamma flux could signal the presence of neutralinos or other dark matter candidates.
Six types of quark (u, d, s, c, b and t) have been found experimentally, however all matter on Earth is made up of only two types of quarks (u and d). It is a fundamental question whether there is matter made up of three quarks (u, d and s). This matter is known as Strangelets. Strangelets can have extremely large mass and very small charge-to-mass ratios. It would be a totally new form of matter. AMS will provide a definitive answer on the existence of this extraordinary matter. The above three examples indicates that AMS will probe the foundations of modern physics.
Cosmic radiation is a significant obstacle to a manned space flight to Mars. Accurate measurements of the cosmic ray environment are needed to plan appropriate countermeasures. Most cosmic ray studies are done by balloon-borne satellites with flight times that are measured in days; these studies have shown significant variations. AMS-02 will be operative on the ISS for a nominal mission of 3 years, gathering an immense amount of accurate data and allowing measurements of the long term variation of the cosmic ray flux over a wide energy range, for nuclei from protons to iron. After the nominal mission, AMS-02 can continue to provide cosmic ray measurements. In addition to the understanding the radiation protection required for manned interplanetary flight, this data will allow the interstellar propagation and origins of cosmic rays to be pinned down. See: The newly-installed Alpha Magnetic Spectrometer-2 (AMS)