http://popups.lib.uliege.be/1373-5411/index.php?id=2992 Index terms fr 0 http://popups.lib.uliege.be/1373-5411/index.php?id=2988 Starting from a requirement of space-time symmetry, we propose several concepts of additional time dimensions, we study the consequences of the introduction of a multi- dimensional time in the special theory of Relativity and in relativist quantum theory. We show that the mathematical process for generalizing the Dirac equation requires octonions and a 8 dimensional space-time with a privileged time direction. We also show that unlikely quantum correlations in pair of particles (as well as mechanical correlations in two coupled harmonic oscillators) imply a homogeneous 3-dimensional time due to the inseparability of space coordinates in the space continuum. We then propose to define a 3-dimensional time with quantum hidden variables and we suggest that the scalar energy conservation is a consequence of the general parallelism of time flow at the macroscopic level. Wed, 04 Sep 2024 09:11:22 +0200 Wed, 04 Sep 2024 09:11:40 +0200 http://popups.lib.uliege.be/1373-5411/index.php?id=2988