Germany was clearly the world leader in physics at the end of the 1800s/beginning of the 1900s. In fact, I have to believe that the world would look a lot different in terms of science and technology if that idiot of all idiots Hitler had not driven many of the brightest German minds in physics out of the country because they were Jews (Einstein, for example). Perhaps the Germans would have been the first to the moon, for example.
Here are some of the highlights of this chapter:
- In 1888 Hertz invented a device that could send electromagnetic waves across a room. He thought the discovery was "of no use whatsoever," but he had produced radio waves that we now use in all our communication, remote controls, etc.
- In 1895 Röntgen discovered x-rays
- In 1900, Max Planck gave birth to quantum physics by suggesting that energy increased and decreased in discrete packages called quanta.
- 1905 was the "annus mirabilis" of science (wonderful year). Einstein published three papers, the third one gave birth to he special theory of relativity. It argued that time moves faster or slower depending on the speed something is traveling.
- Richard Dedekind defined continuity in math not in terms of "nothing between" but in terms of numbers connecting both to what comes before and after.
- Georg Cantor invented set theory and argued that some infinite sets are bigger than others. Yet he also proved that the number of points on a line segment is equal to the number of points on a plane figure.
- Frege and Husserl are mentioned in relation to the philosophy of number but their contributions are not completely clear to me. I have taken from Frege myself the parable of "sense and reference" in the meaning of words. Wittgenstein undermines this model significantly, but I still find it useful in many circumstances. It's the idea that a word has both a sense and a reference. The reference is what it points to in the real world.
I have little interest in Husserl. I feel sorry for him and the way his life ended. He thankfully passed before Hitler rounded him up but Heidegger apparently left him out to dry after he lost his post at Freiburg. In general, though, I have little interest in the phenomenological school of philosophy, which seems to reign supreme across the map of my philosophical world right now.
- Finally there's Hilbert. He and Einstein developed the notion of "infinite dimension Euclidean space" or, as it is called, "Hilbert space." He and Einstein developed general (rather than special) relativity.