NATS 1740 Lecture Notes - Lecture 3: Double-Slit Experiment, Antiparticle, Electromagnetism

• School: York University
• Department: Natural Science
• Course: NATS 1740
• Professor: Radu Campeanu

Document Summary

Describe how bohr"s quantum model explains atomic spectra. Describe the entanglement of states and processes. In 1932 curie discovers artificial nuclear transmutations, chadwick discovers the neutron and anderson discovers the positron. Neutrons were assumed to collide with charged particles in ionization chambers. These particles were produced through nuclear transmutations created with particle accelerators (cockcroft & walton 1928). Neutrons were needed in the structure of the atomic nucleus. Positrons were seen in cosmic rays with observation chambers mounted on balloons. It was predicted theoretically by paul dirac in 1929. In the next years new anti-particles were discovered and the universe had a new symmetry. Wherever there is enough energy (radiation, colliding particles) nature creates them. Einstein"s e=mc2 gives the masses of these pairs. There is no evidence that the universe contains anti-matter, that is anti-atoms such as anti-hydrogen. Matter at the molecular and atomic level is governed by the electromagnetic force.