Energy Debt and Credit
As previously argued there is an acceleration effect limit of 1G between stars. Therefore the space vehicle may reach an acceleration constant of close to infinity, the mass becoming infinitely smaller. For example in applying F=MA, if M is 100 and A is 1, F is 100. (100=100x1). In applying more Force to accelerate, M becomes 1 and A becomes 1000 (1000=1x1000). Since there is an acceleration effect limit of 1G between stars (there being no natural gravity pull between stars), the occupants of the space vehicle would experience no sensory difference between F of 100 or 1,000. The limit to a journey to the stars (assuming high quantity of Orion Energy Project release) is thus based on energy debt and credit.
Energy Debt and Credit continued
A zero sum balance is where the direction of force applied is applied oppositely at the midway point. That is to accelerate to the halfway, revolving 180 degrees and de-accelerating the remaining half distance, the most energy efficient. Accelerating until 90% of the distance is covered, would leave only 10% of the distance remaining in which to de-accelerate. The energy debt is thus 40% (90-(100/2)) and would require a credit of 60% (10+(100/2)). There is a relative differential between the energy debt and credit.