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E.W. Dijkstra Archive: On the cruelty of really teaching computing science (EWD 1036)

For Dijkstra, programming was closer to mathematics than to a craft. The goal wasn’t to “get a feel” for code. The goal was to reason about it rigorously, to understand why it works before discovering whether it works.


The second part of this talk pursues some of the scientific and educational consequences of the assumption that computers represent a radical novelty. In order to give this assumption clear contents, we have to be much more precise as to what we mean in this context by the adjective “radical”. We shall do so in the first part of this talk, in which we shall furthermore supply evidence in support of our assumption.

The usual way in which we plan today for tomorrow is in yesterday’s vocabulary. We do so, because we try to get away with the concepts we are familiar with and that have acquired their meanings in our past experience. Of course, the words and the concepts don’t quite fit because our future differs from our past, but then we stretch them a little bit. Linguists are quite familiar with the phenomenon that the meanings of words evolve over time, but also know that this is a slow and gradual process.

It is the most common way of trying to cope with novelty: by means of metaphors and analogies we try to link the new to the old, the novel to the familiar. Under sufficiently slow and gradual change, it works reasonably well; in the case of a sharp discontinuity, however, the method breaks down: though we may glorify it with the name “common sense”, our past experience is no longer relevant, the analogies become too shallow, and the metaphors become more misleading than illuminating. This is the situation that is characteristic for the “radical” novelty.

Innovative Mars rovers ‘swim’ through the sand

Some animals can move efficiently beneath granular surfaces. These include the sandfish (Scincus scincus), a lizard native to the Sahara. It can burrow into the sand and then literally “swim” through the desert sand to hunt or escape predators.

The principles of movement underlying this ability have only been understood for a few years. Researchers at the University of Würzburg have now translated the sandfish’s locomotion mechanism into an initial technical solution—an innovative Mars rover that outperforms other models when moving on sand.

The team led by computer scientist Marco Schmidt, Professor for Embedded Systems and Sensors for Earth Observation (ESSEO), is collaborating with researchers from Bremen. The project is part of the VaMEx initiative of the German Aerospace Center.

Axial encoding unlocks up to eightfold faster 3D microscopy with less light

A research team from HKU Engineering has pioneered a fundamentally new imaging strategy known as AIMED (Arbitrary illumination microscopy with encoded depth), which utilizes a sub-sampling approach. By integrating innovations in axial optical encoding with advanced computational image reconstruction, the AIMED technology enables a substantial increase in 3D imaging speed while enhancing photon safety, all with minimal additional system complexity. This breakthrough demonstrates significant advantages across efficiency, image quality, and system compatibility.

This work was conducted by the OMEGA laboratory under the leadership of Professor Kenneth K. Y. Wong of the Department of Electrical and Computer Engineering at the University of Hong Kong (HKU). The study is published in the journal Advanced Photonics.

Better math discriminates exotic from classical materials

The planar Hall effect is a tabletop diagnostic tool for special quantum properties useful in basic research and technological applications. Or so it was thought, because careful calculation by Kobe University researchers clarifies the conditions under which this effect may also appear in classical materials. This makes the diagnostic more meaningful and enables more purposeful design.

In the hunt for materials with properties that are useful for quantum computing or spintronics, researchers have used the “planar Hall effect” as a tabletop diagnostic tool: The researchers send a current through a thin, flat sample and observe whether an electric voltage is produced in response to a magnetic field in the same plane as the sample.

If it is, the pattern of how the voltage responds to rotating the magnetic field in the plane of the sample tells researchers about the properties of the material.

The quantum internet, explained

The quantum internet is a network of quantum computers that will someday send, compute, and receive information encoded in quantum states. The quantum internet will not replace the modern or “classical” internet; instead, it will provide new functionalities such as quantum cryptography and quantum cloud computing.

While the full implications of the quantum internet won’t be known for some time, several applications have been theorized and some, like quantum key distribution, are already in use.

It’s unclear when a full-scale global quantum internet will be deployed, but researchers estimate that interstate quantum networks will be established within the United States in the next 10 to 15 years.

Thanks to a push from Joe Rogan, Tucker Carlson and an army of MAHA influencers, Ancient Crunch sells 500,000 bags of its $13 seed-oil-free Masa chips every month

Having launched a potato version last year and with a popcorn line on the way, the founders hope to build the LVMH of healthy snack foods.

Researchers teach brain cells to play ‘Doom’

Investigadores enseñan a las células cerebrales a jugar a ‘Doom’


Australian researchers have trained lab-grown brain cells on a silicon computer chip to play the nineties shooter game “Doom” and say they are just scratching the surface of what the neurons could be capable of doing.

It’s the science-fiction work of biotech boffins at Cortical Labs, who researched and developed the technology that harnesses the workings of the brain’s networking system.

Each so-called “biological computer” contains around 200,000 living human brain cells, grown from stem cells that were harvested from blood donations.

3D silicon circuits bring denser computer chips closer to reality

Through new research published in Nature, Qing Cao and colleagues at the University of Illinois Urbana-Champaign have developed a new approach that sidesteps these problems, bringing high-performance 3D chips a step closer to reality.

Overheated stacks of transistors

Modern computer chips are built on thin wafers of silicon, with transistors (the tiny switches that process information) arranged in a single flat layer. If multiple layers of transistors could instead be stacked on top of each other on the same chip, it would dramatically increase their density without enlarging the chip’s footprint. However, this 3D design would cause the chip to overheat, which could destroy the circuitry already laid down beneath it.

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