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Unleash your imagination. Shape the future.

Deforestation of our tropical rain forests, global warming, human overpopulation, Corona pandemic.  "Is this the end of times...?" I like reading books. How the end of time looks like is described more precisely in the book “Brief Answers to the Big Questions”. It is a small book written by Stephen Hawking, where he answers such big questions. In all its smallness it is a great book, because it is not a theoretical book. Well, partly it is, because questions like what’s inside a black hole, and whether people can time-travel, most people don’t consider as very practical. Its greatness comes from Hawking explaining the answers to the big questions in laymen’s wording, and making clearer why it is important to at least try to answer such Big Questions. Hawking does a great job, not only in answering these more theoretical questions but also the practical, more urgent ones, like “will we survive on earth”, “will AI outsmarten us” and “how should we shape our future.” There are t...

The urgency of digital ethics

To fully understand the urgency of digital ethics, we need to go back to the basis of AI. There are many definitions of what AI is or could be, but I think most clarifying is what the “god-father” of our current computers has to say about this topic. Seventy years ago, Alan Turing described in his ground-breaking paper “Computing Machinery and Intelligence” (Mind, 1950), what according to him makes machines intelligent. In his paper Turing explains that it is not about definitions but about being pragmatic. He describes his now-called Turing test, in order to test whether machines can think: Instead of attempting such a definition I shall replace the question by another, which is closely related to it and is expressed in relatively unambiguous words. The new form of the problem can be described in terms of a game which we call the 'imitation game.' It is played with three people, a man (A), a woman (B), and an interrogator (C) who may be of either sex. The interrogator stays...

Feynman's Lost Lecture: The Motion of Planets Around the Sun

This book is about the lost lecture of Richard Feynman on the motion of the planets around the sun. It is not a book by Feynman but by David and Judith Goodstein. The book contains Feynman’s elementary proof that planets move in elliptical orbits around the sun (being one of the focus points) by first showing that the so-called velocity orbit of each planet is a perfect circle. For this fact he “only” needs the famous laws of Newton and the law of gravity. Elementary, but not simple at all. Feynman's reasoning is based on the work of Sir Isaac Newton, however he deviates at the point where he could not follow the arguments of Newton anymore. Feynman challenged himself in providing a geometric proof in the tradition of the ancient scholars instead of using the nowadays more custom analytical methods. As he states himself his proof is elementary but not simple. The whole idea behind this proof is truly elegant. Instead of focusing on the orbit swiped out by the "position...

Incompleteness: The Proof and Paradox of Kurt Gödel

This book is about the life and work of Kurt Gödel. And what better way to start a book on Gödel’s Incompleteness theorems, by adding, as a first note in your book, a self-referencing note? That is what Rebecca Goldstein does in “Incompleteness”, by ending her first note with an additional note that there are two types of notes used in her book, namely footnotes and endnotes. But in her charming book she does much more than only adding notes to some theorems, by explaining that self-reference, and the logical paradoxes it leads to, are really at the heart of Gödel’s proof of his incompleteness theorems. She outlines the proof very well leaving out the technical details, but in such a way that an interested layman can still appreciate the crux of it. Next to her explanation on the incompleteness theorems, she does a great job by putting the work done by Kurt Gödel in its historical context and describing the man behind the theorems. And what a man Gödel was: closely befriended with Al...

The limitations of technology

In this age of technology, this era of digital revolutions, the question becomes more and more relevant how far technology can get us and what its limitations are. Surprisingly enough, already one century ago, even before the first computers existed, these limits have been settled. These had been found by Kurt Gödel and Alan Turing. They proved that so-called “self-reference” was always inevitably leading to logical paradoxes destroying the rigorous foundations of both mathematics and computer science. Self-reference is the ability to completely describe yourself - stepping back and reflect on yourself. Their proofs are ingenious, both simple on the high level as complicated on the detailed level. But let’s take some time to step back and reflect ourselves; bear with me and try the following thought-experiment to better understand what Gödel and Turing were saying. Suppose I would offer you the perfect VR device, that is one where you cannot not tell the difference between the "...

QED: The Strange Theory of Light and Matter

This book is about quantum electrodynamics, the theory which describes how light and matter interact on the smallest scales. As can be expected from any book by Richard Feynman, this book is a joy to read. Feynman manages to explain in clear layman's terms why it seems that light travels by straight lines, how light reflects from surfaces, why it behaves wave-like and how light-particles interact with electrons. In the final part of the book he concludes with an appetizer on the so-called quantum chromodynamics (QCD), which is the theory of the (strong) interaction between even more exotic particles. Feynman takes the reader by the hand starting with simple examples and step-by-step advance on those examples pointing out the strangeness of the theory when scales or distances get very, very small. It would not make sense to summarise here what is so perfectly described in his book, best is to read it yourself. However I want to mention the main take-out for me, which is that the ...

Let inspiration be your compass...!

Were you ever, when taking a bath, suddenly struck by the insight that the upward force on your body by the surrounding water is equal to the weight of the water displaced by your body? It’s a matter of balance between the displaced weight and the induced upward force. It inspired Archimedes to his law of up-thrust. Were you ever, when taking a nap, suddenly awaken by the fall of an apple on your head, and came to realize that you were hit by the force of gravity? The same gravity holds the moon into orbit, and, less distant, our airplanes. This was also a matter of balance, which inspired Newton to his famous laws of gravity. And did you ever look at a pocket compass and wondered what it was in the surrounding empty space that was moving the needle? Where do you go to when there is nothing surrounding you? This wonder inspired Einstein to his theories of relativity and gravitation.All these great men were inspired by Mother Nature to represent the real world by simple models. Their i...