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The Internet: A Failed Mass Experiment?

13 min

The Internet was never approved as an experiment on human beings, yet it became one: an uncontrolled trial in which anyone could test anything on anyone, with no…

Hans-Dieter A. Hiep

Aug 3, 2026

A sound and complete proof system for separation logic (part 1)

26 min

A novel proof system for separation logic is explained.

Hans-Dieter A. Hiep, Frank S. de Boer

Jun 29, 2024

On invariance and inconsistency

24 min

Program correctness is not easy: the requirements of a program may be inconsistent, or there may not even exist a correct program that satisfies the requirements. This…

Hans-Dieter A. Hiep

Feb 16, 2024

Can the Collatz conjecture be proven, or not?

24 min

We review a recent preprint article about the Collatz conjecture. The Collatz conjecture is a more than eighty years old problem that is still unsolved.

Hans-Dieter A. Hiep

Nov 1, 2023

What is an education?

11 min

This article describes what I think is the essence of education.

Hans-Dieter A. Hiep

May 6, 2023

Correctness of two sorting algorithms

21 min

This article describes two sorting algorithms (gnome sort and bozosort) and gives their correctness proof in full detail.

Hans-Dieter A. Hiep

Mar 15, 2023

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