Ruler measurements give space-time-transformation-independent invariant lengths

TL;DR

This paper argues that ruler measurements of spatial intervals are invariant across reference frames and independent of space-time transformations, challenging the conventional notion of length contraction in special relativity.

Contribution

It demonstrates through thought experiments that spatial intervals measured by rulers are invariant, questioning the physical reality of length contraction in special relativity.

Findings

Ruler measurements are frame-independent.

Length contraction is argued to be unphysical.

Spatial intervals do not depend on space-time transformations.

Abstract

Two thought experiments are described in which ruler measurements of spatial intervals are performed in different reference frames. They demonstrate that such intervals are frame-independent as well as independent of the nature of the space-time transformation equations. As explained in detail elsewhere, the `length contraction' effect of conventional special relativity theory is therefore spurious and unphysical.