Feb 12, 2018:
In terms of information theory, information has nothing to do with meaning. That is the highest form of truth. The lecture example took a while to sink in: If “U” always follows “Q” with absolute certainty, then “U” has no information to provide.
Another take on information versus meaning: If a planetary rover on Mars detects a stationary rock in its path, the only information is its size, shape, and location (very little uncertainty). If the same rover detects a moving object on the surface, add velocity and heading to the previous three pieces of information, and describe location as current. There is a bit more uncertainty, but less and less as the behavior is observed over time. Even if the object is flying past the rover it only adds altitude and another axis of heading. All just information until meaning is assigned by a human operator at a ground station on Earth. Auto-complete filling in fields on a computer works in a similar way. There is no meaning other than what the operator assigns. Just information.
Not sure whether to feel insignificant or lucky to be alive in an age such as this. Who’s watching us? Are we just information, or do we have meaning?
Claude Shannon ties with Vannevar Bush when it comes to coolest people I’d never heard of before this class. The Mars planetary rover mentioned earlier is the logical extension of Shannon’s Theseus (electro-mechanical mouse in a maze). Autonomous vehicles like the Global Hawk recon aircraft are also today’s Theseus. We’re no more intelligent than those who came before us, we just have more capable technology. If Shannon were transported to the present day, he’d be up to speed on our tech within two weeks and building things he could only dream of in his day.
Feb 14, 2018:
Bumper music courtesy of The Meters.
Like an earlier lecture that dealt with WWII and the Cold War, this is one of my comfort zones. Familiar ground, especially the last years of the Cold War. We ought to thank the Soviets. Were it not for them, we wouldn’t have developed many of the technologies they went to so much trouble to buy or steal from us.
What’s the difference between signal and noise? If you look at low enough amplitudes and fast enough sample rates, it all looks like noise. In telephony, of course, signal is the desired intelligence transmitted over wire or wireless means, and noise is the deterioration over distance. The sIgnal + noise / noise ratio used to be a measure of line or channel quality. Of course, that was when “hanging up the phone,” and ‘rolling down the car window” made literal sense.
Computers: Thank you, Military-Industrial Complex. Imagine the relays, tubes, and wiring harnesses buried deep in so many landfills (Maybe not wire harnesses; people used to burn off the insulation and sell the copper for scrap), their roles in progress forgotten. Tubes. Were it not for tubes, the transistor would never have been born. Transistor-transistor logic begat IC chips with layers of transistors etched smaller than imagination. Nostalgia is nice, but I’m glad to live in the 21st century.
Even when tubes and relays were still lighting and clicking in some computers, the seeds of the internet were sewn. Networks, multiple users time-sharing mainframe computer time, all led to where we are today. Doug Englebart and Tim Berners-Lee are among the giants upon whose shoulders we stand to see farther today. Their names deserve to be better known outside the IT community.