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Reviving Nikola Tesla

By Shlomo Maital

Nikola Tesla

Thanks to Elon Musk and his Tesla electric cars, the genius inventor Nikola Tesla and his achievements have been revived.

           Tesla was born and raised in what is now Serbia, in the Austro-Hungarian empire. He was trained as an engineer. After migrating to the US, he worked for a time with Thomas Edison. However, they had an argument. Tesla believes that the future of electricity lay in alternating current. Edison was committed to direct current.

             Tesla left Edison’s shop and went to work for George Westinghouse. There, with Westinghouse, Tesla built an alternating-current electric motor, whose design we employ to this day. It was vastly better than direct-current motors. It did not need powerful permanent magnets.   The AC motor formed the basis of the Second Industrial Revolution.

             Tesla invented many other things. He invented the “logic gate” which became the foundation for semiconductors. He built a robotic drone (“teleautomaton”, he called it). He tried to find how to transmit electricity wirelessly – we’re still trying to do that.

               But Tesla died poor, in New York City, in 1943.   He was never able to truly partner with industrial giants who had the money to finance his inventions. Edison, in contrast, was a genius at doing that, and got J.P. Morgan, the banker, to fund his initial electricity company. (Edison was smart enough to ‘electrify’ Wall St first, and J.P. Morgan’s home).  

               Today we follow Tesla, not Edison. We use AC current, not DC.  

                 There is a lesson here.   In order for creative ideas to be actuated, you need resources. That means, you have to communicate your idea to those who can best help implement it, and then work with them, with empathy. Tesla failed at this. But his ideas did change the world. And so are Munk’s Tesla cars. Thanks, Elon, for helping us remember this genius inventor.

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Brain Soup

By Shlomo Maital

Suzana Herculano-Houzel

How do you count the number of neurons (brain cells) in a brain (whether human or animal)?   Dr. Suzana Herculano-Houzel, Vanderbilt University, has found a creative way.

   Previously, the method was to take samples of brain tissue, freeze it, put it under a microscope and count neurons. But this was inaccurate, because neuron density in brains varies widely, depending on the place within the brain.   Using this method we thought the brain had 100 billion neurons. That’s not a lot – elephants have three times more!

   Herculano-Houzel read an old 1970’s study, suggesting, why not measure the amount of DNA in a brain, then divide by the amount of DNA per neuron?   Hmmm… problem is, DNA per neuron varies widely.

   So she developed a new, creative method.   Take a brain.   Puree it using a blender. (Honest!).   Brain soup, she calls it.   Mark the neurons with a chemical dye, then mark again with a red dye to mark the nucleus of the neurons. Neurons have only one nucleus, like all cells. So if you count the neuron nucleuses, you can compute how many neurons there are in the brain.

   Answer?   86 billion.   Or, 14% fewer than we thought (100 b.).

   So why are humans so smart? The key part of the brain, that makes us smart, is the cerebral cortex, that wrinkled outer part of the brain. Because it is wrinkled, it has a lot of surface area, enabling more neurons to pack it.   Turns out we have 16 b. neurons in the cerebral cortex, while orangutans and gorillas have 9 billion, and chimps have 6 billion. (Those are respectable numbers – those primates are clever!).

     And those 16 b. neurons in the cerebral cortex are waht makes us smart, and it is probably where Dr. Suzana got the idea…   Hey, why did no-one else think of it before?

Blog entries written by Prof. Shlomo Maital

Shlomo Maital
January 2018
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