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Memristor?

Anyone who has played around with electric circuits knows resistors, capacitors, and inductors.  Few people knows about memristors though.  The memristor idea was thought up by Professor Leon Chua in 1971 and physical devices were just intentionally created in the lab in 2008.

An adventure story of how physical memristors were created is given by R. Stanley Williams, one of the inventors, here.  Below are the excerpts about what a memristor is and how a 31-year-old, mostly-forgotten theory provided a breakthrough in understanding the experiments:

Memristor is a contraction of “memory resistor,” because that is exactly its function: to remember its history. A memristor is a two-terminal device whose resistance depends on the magnitude and polarity of the voltage applied to it and the length of time that voltage has been applied. When you turn off the voltage, the memristor remembers its most recent resistance until the next time you turn it on, whether that happens a day later or a year later.

and

We were frustrated and burned out. Here we were, in late 2002, six years into our research. We had something that worked, but we couldn’t figure out why, we couldn’t model it, and we sure couldn’t engineer it. That’s when Greg Snider, who had worked with Kuekes on the Teramac, brought me the Chua memristor paper from the September 1971 IEEE Transactions on Circuits Theory. “I don’t know what you guys are building,” he told me, “but this is what I want.”

To this day, I have no idea how Greg happened to come across that paper. Few people had read it, fewer had understood it, and fewer still had cited it. At that point, the paper was 31 years old and apparently headed for the proverbial dustbin of history. I wish I could say I took one look and yelled, “Eureka!” But in fact, the paper sat on my desk for months before I even tried to read it. When I did study it, I found the concepts and the equations unfamiliar and hard to follow. But I kept at it because something had caught my eye, as it had Greg’s: Chua had included a graph that looked suspiciously similar to the experimental data we were collecting.

But what memristors can be used for?  The author suggests super-dense, super fast digital memory that does not requires electrical current to keep its state (for computers that turns instantly on and off), and an analog simulation of the brain (by encoding synaptic strengths using memristors.)   

Memento mori?

According to Wikipedia, Memento mori may be translated as "Remember that you will die.",  a warning that is applicable to human throughout our history.

However, many people such as these people are working on making death unnecessary.   Hopefully, we will live long enough for their research to be practical.  After that we can wait for brain state backup technologies and escape from our mortal flesh eventually.

On a slightly related note, one speculation that tries to explain the Fermi's Paradox is that the aliens already uploaded their mind to other computational substrate and don't care so much to contact primitive technological societies like ours.  The uploaded minds might use little energy, can be transmitted at the speed of light, can exploit computational capacity of complex systems found in the universe, and can run at much higher speed than biological hardware, making their subjective time much faster.  Due to this time scale difference, their conversation with us might be similar to our conversation with a tree.

Autistic People Cannot Lie (Easily)

I found this essay by Simon Baron-Cohen (the psychologist whose cousin is Borat's Sacha Baron-Cohen) about people with autism and Asperger's syndrome and their lack of lying skill very interesting.

From the essay:

"And then there are people with autism. Their neurological condition leads not only to difficulties socializing and chatting but also to difficulties recognizing when someone might be deceiving them or understanding how to deceive others. Many children with autism are perplexed by why someone would even want to deceive others, or why someone would think about fiction or pretense. They have no difficulty with facts (version 1 of reality) and can tell you easily if something is true or false (“Is the moon made of rocks? Yes! Is the moon made of cheese? No!”). But they may be puzzled by version 2 of reality, that “John believes the moon is made of cheese.” Why would a person believe something that is untrue?"

By the way, the inventor of BitTorrent, Bram Cohen also has Asperger's syndrome.