Physics Honors AB –Day 12/9 & 12/10 Special and General Relativity

Agenda Special Relativity Time Dilation Problem Length Contraction General Relativity Implications for Gravity

Historically – where are we? Luminerous Ether – The medium in which light traveled just like sound waves in air Proposed by Aristotle and common belief up until the end of the 19 th Century

Historically – where are we? Michelson-Morley Experiment conducted in 1887 unexpectedly helped to disprove the existence of the Ether

Albert Einstein Studied Physics as a graduate student at Swiss Polytechnic University Worked in Patent Office and Married with a child when he published his 4 papers in 1905

The Miracle Year Einstein published 4 papers – the photoelectric effect, Brownian Motion; Special Relativity and the equivalence of matter and energy – that would alter the course of modern physics The papers greeted with apathy Then he got 1 Fan

The Special Theory of Relativity Einstein was obsessed with light and James Clark Maxwell, the father of Electromagnetic Theory. Had a simple question that had large implications “What would you see if you rode on a beam of light?”t But First let’s discuss what is meant from Relativity

Galilean-Newtonian Relativity

What would be the velocity…

So what would happen if it was a light beam instead of a pitch

So what does keeping the speed of light constant affect?

Time dilation Let us look at the set up below, a light beam travels to roof of rail car then back down To the person on the car, the light travels at the speed of light To the stationary observer

Length Contraction

Twin Paradox

Special Relativity … Only valid for non accelerating reference frames Once you have acceleration it falls apart He wanted to incorporate Gravity

General Theory of Relativity

Mass causes a curvature in Space-Time

2 Mass causes a curvature in Space-Time

How does Gravity Propagate

Light interacting with Curved Space - Time

Gravitational Lensing After World War I, British Scientist proved Einstein’s Theory of General Relativity by observing the bending of star light during a solar eclipse

Gravitational Lensing Einstein Cross

Gravitational Lensing Einstein Ring

For Test Explain why Einstein is so important to Physics. What were his contributions and how are they apparent today? Be specific and give examples Historical Documentary Panel Discussion – Some awesome Physicists discuss Einstein