relativity. principle of relativity postulates of relativity special theory of relativity general...

14
RELATIVITY

Upload: debra-peters

Post on 20-Jan-2016

338 views

Category:

Documents


5 download

TRANSCRIPT

Page 1: RELATIVITY. Principle of Relativity Postulates of Relativity Special Theory of Relativity General Theory of Relativity

RELATIVITY

Page 2: RELATIVITY. Principle of Relativity Postulates of Relativity Special Theory of Relativity General Theory of Relativity

• Principle of Relativity• Postulates of Relativity• Special Theory of Relativity• General Theory of Relativity

Page 3: RELATIVITY. Principle of Relativity Postulates of Relativity Special Theory of Relativity General Theory of Relativity

Galilean Principle of Relativity

Any two observers moving at constant speed and direction with respect to one another will obtain the same results for all mechanical experiments.

-Galileo Galilei

Page 4: RELATIVITY. Principle of Relativity Postulates of Relativity Special Theory of Relativity General Theory of Relativity

Albert EinsteinConcerned with the lack of inner perfection in electromagnetic theory and created special theory of relativity.Are the Law of Induction and Maxwell’s modification of Ampere’s Law really different?

1879-1955; Germany, Switzerland, and USA

Page 5: RELATIVITY. Principle of Relativity Postulates of Relativity Special Theory of Relativity General Theory of Relativity

What would the world look like if I rode on a beam of light?

The clock tower in Bern, Switzerland. Einstein’s home (1903-1905) was only 200m from the tower.If light has a constant speed, then all observers see the clock at slightly different times, depending upon distance. One of Einstein’s first thought experiemnts: What if the streetcar moved away from the clock tower at the speed of light?

Page 6: RELATIVITY. Principle of Relativity Postulates of Relativity Special Theory of Relativity General Theory of Relativity

Einstein’s Annus Mirabilis: 1905Four Papers published while he was a patent clerk in Bern, Switzerland

Paper Focus

On a Heuristic Viewpoint Concerning the Production and Transformation of Light

Photoelectric effect, defined the quantum

On the Motion of Small Particles Suspended in a Stationary Liquid, as Required by the Molecular Kinetic Theory of Heat

Brownian motion, gave empirical evidence for the existence of atoms

On the Electrodynamics of Moving Bodies Special Relativity

Does the Inertia of a Body Depend Upon Its Energy Content?

Matter-energy equivalence,  E = mc2

Page 7: RELATIVITY. Principle of Relativity Postulates of Relativity Special Theory of Relativity General Theory of Relativity

Postulates of Special Relativity• The Principle of Relativity – The laws by which the states

of physical systems undergo change are not affected, whether these changes of state be referred to the one or the other of two systems in uniform translatory motion relative to each other.

• The Principle of Invariant Light Speed – "... light is always propagated in empty space with a definite velocity [speed] c which is independent of the state of motion of the emitting body." (from the preface). That is, light in vacuum propagates with the speed c (a fixed constant, independent of direction) in at least one system of inertial coordinates (the "stationary system"), regardless of the state of motion of the light source.

Page 8: RELATIVITY. Principle of Relativity Postulates of Relativity Special Theory of Relativity General Theory of Relativity

Lorentz Contraction• Einstein used the

mathematical tools generated by Hendrik Lorentz in his 1905 paper on special relativity.

• Lorentz maintained that the ether must exist.

Hendrik Antoon Lorentz, (1853-1928) Netherlands

Page 9: RELATIVITY. Principle of Relativity Postulates of Relativity Special Theory of Relativity General Theory of Relativity

Jules Henri Poincaré• Accomplished mathematician, physicist,

engineer, and philosopher of science• Published the principle of relativity just

before Einstein’s paper in 1905 and stated experiment cannot distinguish between states of uniform motion and rest

• Poincaré took the Lorenz transformations and put them into a modern form

• Poincaré never acknowledged Einstein’s work on special relativity and died before publication of the General Theory 1854-1912, France

Page 10: RELATIVITY. Principle of Relativity Postulates of Relativity Special Theory of Relativity General Theory of Relativity

Consequences of the Postulates of Relativity

• Time and distance are measured differently in different inertial frames.

• Time is dilated and lengths are contracted in the direction of motion.

• Thus, between two different inertial frames, measurements of time and distance are relative.

Page 11: RELATIVITY. Principle of Relativity Postulates of Relativity Special Theory of Relativity General Theory of Relativity

The General Theory of Relativity

• A theory about gravity in spacetime• Published in 1916• Principle of equivalence

Page 12: RELATIVITY. Principle of Relativity Postulates of Relativity Special Theory of Relativity General Theory of Relativity

Arthur Stanley Eddington

• The earliest English-speaking physicist who used Einstein’s German science during WWI

• Headed expedition to South Pacific to observe a solar eclipse on 29 May 1919 as a test of General Relativity

1882-1944; Britain

Page 13: RELATIVITY. Principle of Relativity Postulates of Relativity Special Theory of Relativity General Theory of Relativity

GRAVTATIONAL LENSING

Page 14: RELATIVITY. Principle of Relativity Postulates of Relativity Special Theory of Relativity General Theory of Relativity