About The Timelines
Tracking time in The Ido Chronicles is rather complex, due in part to the ability of individuals to modify their own experience of time flow. The changing rate of time flow is called "tempo" - tempo can change from a strict minimal value of unity (1,0) to any arbitrarily high rate of slowing, and tempo is changed via the binach-based information processor called the "binup", incorporated into every human's brain prior to birth. Tempo control is actually achieved via a low frequency quantum resonance field (i.e. "new physics"), and the field can be applied to any collection of particles - hence tempo control can be exercised on animals and even on so-called inert matter.
The second factor that affects the tracking of time is the recourse to relativistic speeds for interstellar travel, and hence the presence of significant time dilation. Starships (whether arships or jonahs) are based on an advanced Bussard Ramjet design and almost all interstellar transport uses ramjet propulsion. Even for relatively short trips (that is, only a few light years), speeds above 90% light speed are achieved, and usually speeds attained are higher than 99% light speed. The top speed limit is variable, but is the result of the increasing "heaviness" of the interstellar medium as the relativistic speed gets closer and closer to light speed. As the interactions become more energetic, more shielding is required to protect the human passengers from radiation, which, despite binach, cannot be fully controlled. Upper speeds therefore rarely exceed 99,9% the speed of light. At this speed, time is slowed by a factor in excess of 22 times.
Because of these two factors, and the high mobility of humans, especially with the dawn of the Third Exodus, the average tempo rate for humans begins to increase rapidly. The larger the Humanitat, that is, the region of space occupied by humans, the higher the average tempo rate becomes. With the advent of tempo control, a new time system was introduced, called Ido Era time. Its starting date is arbitrarily set to the introduction of the game of Ido, and the time rate of flow of Ido Era time is determined by the current average rate of time flow, calculated by sampling tempo control as well as the average effects of time dilation across the Humanitat. At the birth of Grolier Desius, Ido Era time is flowing at a rate of about 650, but by the dawn of the Fourth Exodus, it has increased to a rate above 850. The Fourth Exodus, in turn, will lead to a dramatic increase in average tempo rate. Ido Era time is therefore determined by integrating the time changing tempo rate as a function of time, with a modifying factor due to time dilation during transport. At each epoch, this can be approximated by dividing real time by the appropriate tempo scaling factor and subtracting a constant number of Ido Era years that incorporates the changes in tempo from the beginning of the Ido Game. In rough terms, Ido Era time tracks the average subjective time of the average human. Since humans live for slightly more than two centuries, at the standard tempo rate, a human life would span 200+ Ido Era years.
That said, finding an "average human" is no easy task. Although many communities set their tempo rates to near the average ("human normal", or "humorn") value, others do not. Many individuals adopt tempo values higher than humorn in order to lengthen their real time lives. This may be done for a variety of reasons, not all of them rational.
As a result of these complexities, at least three time scales are in common use - real time, Ido Era time and subjective or proper time. In addition, although subjective and proper time are often treated as equivalent, anyone who uses interstellar transport (or who spends time in an unusually high gravitational field) introduces a time slippage between these two measures, and it becomes necessary to distinguish subjective time from proper time. Both real time and Ido Era time are common to all humans (and other sentient species), while proper and subjective time vary from one individual to another.