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‘That it is possible to find the form of the Lorentz transformations without requiring the speed of light to be the same in every inertial system is rediscovered about every thirty years and, rightly, forgotten.’ This proposition alongside the doctoral dissertation of Hendrik Smid in 1986 provides food for thought: Is the light postulate of special relativity, which gives the speed of light c in vacuum its status of maximum and unchanging speed, indeed not necessary? What kind of physical world are you then left with? What could be the value of discussing this in class? In this paper we show how the Lorentz transformation, which describes the relationship between two coordinate systems moving relative to each other at a constant speed, can indeed be derived by replacing the light postulate by another assumption, namely the requirement of closure under composition of transformations that relate inertial frames of reference (i.e. two successive coordinate transformations of certain type can be written as one transformation of the same type). Although well known in specialised literature of physics research, the remarkable insight that c is somehow buried in nature is hardly mentioned in pre-university and bachelor’s physics courses and textbooks. Yet, the presented comprehensible approach may support the understanding and plausibility of the abstract subject of special relativity. Mathematics may go too far for an average pre-university student, but this subject would certainly not be out of place in an undergraduate physics course or a physics teacher course. Although many teachers do not know that the light postulate of special relativity can be replaced by another assumption or may not appreciate such replacement as part of their teaching of the topic, it offers in our opinion an opportunity to inform students that a critical look at postulates and an investigation of alternatives is an essential part of the nature of science.

When thinking about Olympic winter sports and watching events on television, people mostly focus on events where the chances of success are high for fellow-countrymen. For example, in the Netherlands speed skating is considered the main winter sports event. But with Kimberley Bos there is now also a Dutch medal candidate for the Winter Olympics 2022 in the skeleton discipline. Where speed skaters prepare in summer for the winter season with roller skates, Bos trains on an athletics track with a self-built board on wheels as a replacement for the skeleton. British athletes on the other hand can choose the bobsleigh and skeleton push-start track at the University of Bath for their summer preparation. We prepare for the upcoming Winter Olympics 2022 by taking a physics view on advanced sleighing. We show how school physics helps understanding the motion of athletes in bobsleigh and skeleton and increases respect for the athletes’ performance.