How do you go about pushing the frontiers of propulsion science? Tau Zero Foundation founder Marc Millis discussed the question in a just published interview with h+ Magazine. One aspect of the question is to recognize where we are today. Millis is on record as saying that it may be two to four centuries before we’re ready to launch an Alpha Centauri mission. Why the delay? The problem is not so much high-tech savvy as it is available energy, and Millis evaluates it by comparing the energy we use for rocketry today vs. the entire Earth’s consumption of energy.

The question is how much energy we produce and how much we consume, and what percentage of that is devoted to spaceflight. You can see and hear Millis discussing his calculations on the matter in a presentation he made at the TEDx Brussels 2009 session, one that is linked to from the interview. Obviously, the time to the Centauri stars decreases if we decide to put ten times more energy into the space program than we have historically done. Will we make such a choice?

While we’re working such issues out, Millis advocates backing off the idea of choosing a single best approach for interstellar flight. We’re a long way from actually flying such a mission, and rather than attempting to choose a single course, we do better by researching the entire range of possibilities:

Relative to the technology, as a culture we’re so used to thinking how we can get “there” the quickest, or what’s the best single approach. When it comes to interstellar flight and learning to live beyond Earth, this thinking sidetracks us because we’re so far from fruition in our understanding of interstellar space options, that there’s no way for us to pick “the” one way. Instead, there are many different options and unknowns. We stand to gain a lot more from the attempt to understand them – chipping away at them rather than not doing anything at all. By researching the spectrum of possibilities, we’re likely to be better off in the near term.

A research plan that looks laterally, the way a mountain climber evaluates the best path up? We haven’t explicitly tried that approach in interstellar studies, but Millis backs it:

I really want to change the paradigm of how we look at interstellar flight. It’s not just a matter of trying to get there quickly or to find “the best approach,” rather it’s finding the smartest things we can do today that set the stage for a more productive future. At the Tau Zero Foundation, we cover simple solar sails to the seemingly impossible faster-than-light. Rather than trying to identify the best approach, we’re trying to identify the next steps that students can work on to chip away at where their own personal interests lie.

Most of the h+ interview is spent on current issues, such as the cancellation of the Constellation program and the most realistic way to get to Mars, but those with a yen for breakthrough ideas will enjoy Millis’ thoughts on faster than light travel and the time paradoxes it might introduce. Does quantum entanglement show instantaneous connections between particles or are there other explanations, and are there faster than light implications in all this? Read the interview for more, and bear in mind that the book Millis edited with Eric Davis, Frontiers of Propulsion Science, gets into such questions with a vengeance. Re quantum entanglement and its implications, even Millis calls that the hardest chapter in the book, a statement with which most scientists would agree.