Nifty papers I wrote that nobody knows about (Part 4: Complex Langevin equation)

This is the last installment of the "Nifty Papers" series. Here are the links to Part1Part2, and Part 3.
For those outside the computational physics community, the following words don't mean anything: 

"The Sign Problem"

For those others that have encountered the problem, these words elicit terror. They stand for sleepless nights. They spell despair. They make grown men and women weep helplessly. The Sign Problem. 

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Nifty papers I wrote that nobody knows about: (Part 3: Non-equilibrium Quantum Statistical Mechanics)

This is the third part of the "Nifty Papers" series. Link to Part 1. Link to Part 2.

In 1999, I was in the middle of writing about quantum information theory with my colleague Nicolas Cerf. We had discovered that quantum conditional entropy can be negative, discussed this finding with respect to the problem of quantum measurement,separabilityBell inequalities, as well as the capacity of quantum channels. Heady stuff, you might think. But we were still haunted by Hans Bethe's statement to us that the discovery of negative conditional entropies would change the way we perceive quantum statistical physics. We had an opportunity to write an invited article for a special issue on Quantum Computation in the journal "Chaos, Solitons, and Fractals", and so we decided to take a shot at the "Quantum Statistical Mechanics" angle.

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Nifty papers I wrote that nobody knows about (Part I: Solitons)

I suppose this happens even to the best of us: you write a paper that you think is really cool and has an important insight in it, but nobody ever reads it. Or if they read it, they don't cite it. I was influenced here by the blog post by Claus Wilke, who argues that you should continue writing papers even if nobody reads them. I'm happy to do that, but I also crave attention. If I have a good idea, I want people to notice. 

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On quantum measurement (Part 2: Some history, and John von Neumann is confused)

This is Part 2 of the "On quantum measurement" series. Part 1: (Hans Bethe, the oracle) is here.

Before we begin in earnest, I should warn you, (or ease your mind, whichever is your preference): this sequence has math in it. I'm not in it to dazzle you with math. It's just that I know no other way to convey my thoughts about quantum measurement in a more succinct manner. Math, you see, is a way for those of us who are not quite bright enough, to hold on to thoughts which, without math, would be too daunting to formulate, too ambitious to pursue. Math is for poor thinkers, such as myself. If you are one of those too, come join me. The rest of you: why are you still reading? Oh, you're not. OK. 

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