EinsteinA Man for all Seasons

Harrison B. Prosper15 November, 2005

1945

Einstein

“the essence of his science lay in his artistry –his phenomenal sense of beauty”

Banesh Hoffman, 1975

Spring

1879 – 1900

14 March, 1879, Ulm, Germany

Hermann Einstein

Albert

Pauline Einstein

Ulm, Germany

Map data ©2017 GeoBasis-DE/BKG (©2009), Google, Inst. Geogr. Nacional 100 mi

Ulm

Ulm

Germany

Sunny · 76°F

7:20 PM

Quick facts

Photos

Ulm - Google Maps https://www.google.com/maps/place/Ulm,+Germany/@48.3875039...

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“you will never amount to anything”

In 1880, the Einsteins moved to Munich

Albert developed an intense dislike of school and dropped out at age 15

Albert & Maja, 1893

“I believe in Spinoza’s God who revealshimself in the orderly harmony of whatexists, not in a God who concerns himselfwith the fates and actions of human beings”

Albert Einstein, 1929

Surfing a beam of light

At age 16, Einstein asked himself: what would a light wave look like if one could keep abreast of it ?

He would provide ananswer ten years later……but first he wentto college in Aarau, then Zurich

Aarau class of ‘96MarcelGrossman

Later that year, Einstein entered the EidgenössischeTechnische Hochschule, Zurich. Graduated in 1900.

Summer

1901 – 1915

Technical Expert, Third Class

Einstein got a job at the Swiss Patent Office in Bern, on the 23 June 1902

Six months later, he married his Serbian girlfriend, Mileva

A gathering stormLorentz (1853-1928)Maxwell (1831-1879)

FitzGerald (1851-1901) Max Planck (1858–1947)

1905 – Annus Mirabilis

• 17 March– A new theory of light

• 30 April– A new method to infer size of molecules

• 11 May– A new theory of Brownian motion

• 30 June– A new theory of space and time

• 27 September – m = E / c2

The Photoelectric Effect

No current flows however intense the light

A current flows only if each lightquantum is sufficiently energeticto knock an electron from the metal.

E = h n - W

-

Special Relativity

Principles– The laws of physics are the same in all

inertial frames the principle of relativity

– The velocity of light is independent of the motion of its source or of the observer

Newton’s 5th Deduction

“The motion of bodies in a given vehicle are the same among themselves whether that vehicle is a rest or in uniform motion”

Sir Isaac Newton (1642 – 1727)

Time

d = c t

d = distance between A and Bt = time to go from A to Bc = speed of light in vacuum

The speed of light in vacuum isalways the same

A

B

Time

(c T)2 = (v T)2 + d2

c T

v T

d

T = time to go from A to B

But d ≠ c T

2

cv1 ÷øö

çèæ-=Tt

A B

It isd = c t !!!

Moving clocks run more slowly!

But, what Einstein recognized is that this effect must, by the principleof relativity, be perfectly symmetricalbetween different frames of reference.

Cosmic Ray Muons

Time to the ground 20km / 300,000 km/s ~ 7070 microsecond

For every 35microseconds ofour clock, themuon’s “clock” advancesonly 1 microsecond!

~ 20 km

Muon lifetime ~ 22 microsecond

Mass ~ Energy

E = m c2

Energy to Mass

Fermilab

Energy 1.8 Trillion eV

http://www.fnal.gov

“The happiest thought of my life”In 1907, it suddenly dawned on Einstein that a person falling off a building would be weightless!

http://nssdc.gsfc.nasa.gov

The Principle of Equivalence

1907free space

inside view outside

view

Herr Professor Dr. Einstein

News of Einstein’s radical ideas spread quickly among the leading physicists

This led to many offers of professorships from across the world

In 1914, he became a full professor at the University of Berlin, just at the outbreak of the “War To End All Wars”

Autumn

1915 – 1933

General Relativity, Nov. 1915

Bending of light

Sir Arthur EddingtonEclipse Expeditions 1919

Exhausted, Einstein fell ill in 1917. His devoted nurse was one Elsa Löwenthal.

Arrows of hate

1920: At the instigation of the Nazi Party, a group of German philosophers was convened to discredit Einstein’s theories.

January 1933: The Nazis come to power in Germany. The Einsteins leave for the USA, never to set foot in Germany again.

Winter

1934 – 1955

“We must overcome the horrible obstaclesof national frontiers”

Albert Einstein

Descent into darkness

Einstein, pacifist though he was, concluded that the Nazis were an evil that could be vanquished only by force

2 August, 1939, a month before the start of World War II, he wrote to Roosevelt warning of the grave danger to the world should the Nazis acquire atomic weapons.

Escape from Darkness

Kurt Gödel and Einstein

we should take care not to make the intellectour God….It cannot lead, it can only serve; andit is not fastidious in its choice of leader

100 Hundred Years Later

The Global Positioning System

• What is it ?– A system of 24 satellites in orbit about

Earth that provides accurate world-wide navigation

– Each satellite contains an atomic clock, accurate to ~ 1 nanosecond

– Each satellite emits a unique signal giving its position

Global Positioning System

Period: 12 hours

Orbital radius: 26,600 km

Six planes 60o apart

GPS – Principle

You are here!

1 2 3

ct1 ct2ct3

GPS – ClocksvSatellite

vEarth rSatellite

rEarth

T = time far awayt = time at radius rrS = Schwarzschild

radius

rrTt S−−=

2

cv1

Without correction,the satellite clockswould run fast by 39 microseconds/day39 microseconds/day

1879 – 1955