1 Introduction

In previous work [1] the author has given an Euclidean interpretation of special relativity as an alternative to the Minkowski framework. It introduces the notion of velocity in the (proper) time dimension. Other key elements are the role of proper time $\tau$ , acting as the fourth Euclidean dimension, and the promotion of time $t$ to a fifth Euclidean dimension. It appears that in this context all objects have constant speed $c$ in 4D Euclidean space-time. In the traditional Minkowski framework the 4-velocity vector cannot actually be treated as an extrapolation of 3D spatial velocity vectors. Its components do not behave like in ordinary velocities as has been worked out by the author in [2].

In this paper, the interpretation of time $t$ as a fifth Euclidean dimension, instead of merely a parameter for tracking the objects position on its world-line in 4D Euclidean space-time, will be further justified. Ultimately it will be used to give arguments why mass particles, instead of gravitons, should be seen as the bosons for 5D gravity, in addition to their role as fermions in 4D.