Mozi first described inertia in Chinese text from Warring States period. Aristotle believed objects would move only as long as force applied. Philoponus proposed motion maintained by property imparted during motion. Buridan rejected spontaneous motion-generating property concept. Galileo unified rest and motion principles in 16th century
Observer is a reference frame from which objects or events are measured. Usually inertial, but can be non-inertial like Rindler frame. Reference frames are nonlocal, covering all space and time
Time flows slower near massive objects due to Einstein's relativity. Near a black hole, time passes only hours while Earth takes 1,000 years. Time travel to the future is possible at one second per second
Born in 1879 in Ulm, Germany to Jewish parents. Initially struggled academically, teachers viewed him as lazy. Graduated from Swiss Polytechnic in 1900, worked as patent clerk
Born in Ulm, Germany on March 14, 1879. Saw magnetic compass's northward swing at age four. Failed math test, preventing university teaching position
Born in Ulm, Germany in 1879, moved to Munich and Switzerland. Studied physics and mathematics at Swiss Federal Polytechnic School. Obtained Swiss citizenship in 1901 and worked at Swiss Patent Office