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1800 is good place to start talking about physics

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but the term "physicist" was not coined until about 1840

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before that people who worked in physics might be called natural philosophers

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1800 there was a split based on what "natural philosophers" worked on

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organic matter

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inorganic matter

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the branch that became physics focused on inorganic matter

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1800: battery

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came out of experiments done on animal electricity

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e.g. how we can stimulate nerves in frog legs

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Alessandro Volta made an inorganic version of this

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significance was that you could get a sustained electric current

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before that you could get sporadic electric shocks

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you could store limited amounts of electrical current but no sustained electrical current

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this opened up many kinds of new inventions over the next 100 years

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1800: wave theory of light

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before this, Isaac Newton had the theory of gravity

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became the greatest mind of the time

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so scientist followed his lead on his concept of light as well, light being particles, or straight rays

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around 1800, Thomas Young revived the theory of light as waves

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1820s: electromagnetism

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shown that if you have a sustained current through a wire and you brought a compass needle next to it, it would change directions

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clearly a connection between electricity and magnetism

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1830s

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railroads because to carry passengers, connecting cities

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electromagnetic induction

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mentioned on the first page of Einstein's paper on the special theory of relativity

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loop of wire, bar magnet closer to loop, you generate an electric current, as you move the bar magnet back and forth

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1830s

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telegraph

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if you have a wire and can send current down it, then you can make a communication device

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1860s

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Maxwell's equations

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synthesized and explained the work that people had been doing with electricity in the past half century

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allowed the prediction of electromagnetic waves traveling through space

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the classical theory of electromagnetic radiation

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traveled at a speed close to the known speed of light

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the natural conclusion was that light was an electromagnetic wave

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telegraph still expanding

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under Atlantic Ocean

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expansion of the railroads

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in U.S., transcontinental railroad

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telegraph and railroad went together

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because you need a good signalling system for the trains

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synchronizing of clocks

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cities before that often had different times

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1870s-1890s

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mechanical models

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water waves travel through something, disturbances through water

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this analogy applied to light assumes that there must be some median that light waves travel through, referred to as "ether"

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the French thought the British were going off in the wrong direction

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derided their mechanical models, reminded them of the factory system

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the French physicists prided themselves on clarity and rationality of thought

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interesting to reading obituaries of these scientists

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British: creativity

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French: rationality and clarity of thought

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physics division of labor

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today:

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theoretical physicist

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experimental physicist

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Masters Degree in Engineering from MIT

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19th century

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experimental physicists were at the top

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theoretical physicists really didn't exist

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German universities you typically only had one physics professor

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they were typically experimental physicist who ran the show

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perhaps an assistant

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this was the type of world Einstein was born into

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by the time he was a physicist things started to change

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1879: Einstein born

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1880s

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Incandescent lighting

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Edison's great innovation was the whole system of electric lighting

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the wires

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the switches

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the power

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Einstein's father and uncle were entrepreneurs in Munich

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specialized in incandescent lighting

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won contract to supply lighting for Oktoberfest

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discovery of electromagnetic waver

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Heinrich Hertz

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conclusively proved the existence of electromagnetic waves theorized by James Clerk Maxwell's electromagnetic theory of light

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Hertz, became a term for units of cycles per second

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died in his mid-30s

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radio started almost immediately after this

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1880s

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Michelson-Morley experiment

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if light waves are going to be traveling through the ether

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as the Earth moves around the Sun

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at the surface of the Earth, we should have an "ether breeze" in our face

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therefore if you shine a light in that direction and in the opposite direct

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they found nothing

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there was not "ether breeze" effect

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made people rethink their theories

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1890s

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the electromagnetic worldview

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attempt to "get to the really real" and explain almost everything in terms of electromagnetism

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looking at electromagnetism as the basis of physical reality

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the electron was discovered in the 1890s

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1896-1900

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Einstein in college

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nature of light

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time and space

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came at this from a different direction

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1900-1905

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career up to delivery of his most influential papers