'Interstellar,' the new science fiction film, is rightly praised for its adherence to the real science of black holes, wormholes, extra dimensions and time travel. Moreover, promoting frontier concepts of cosmology builds public appreciation of real science. Successful entertainment need not be all escapist and unscientific like, say, magic ('Harry Potter') and fantasy ('Transformers,' 'X-men').
It goes deeper. Can grasping the exotic nature of reality approach bigger issues of meaning and purpose (if there be any)? What's it all about? Perhaps the philosophy of 'Interstellar,' as well as its science, is worth exploring.
The cutting-edge science comes from Kip Thorne, Feynman Professor of Theoretical Physics, Emeritus, at Caltech, a global authority on gravitation, general relativity and "the warped side of the universe," as he likes to say. Kip is an executive producer of the film and his new book, appropriately, is The Science of Interstellar.
Kip stresses "gravitational anomalies" as both changing the course of astronomy and playing a major role in the film. "Gravitational anomalies are a big deal, today and in the past," he says. "And we're still trying to figure out what's going on." In astronomy, gravitational anomalies in Mercury's orbit were explained by Einstein's general relativity, in rapid rotations of galaxies and stars by "dark matter," and in the shocking accelerating expansion of the universe by "dark energy." In the film, gravitational anomalies are fields in a fifth dimension (called "The Bulk"), which are then harnessed to save humankind.
The science of 'Interstellar' is founded on black holes, which are unimaginably strange, converting all their energy-matter (from a collapsing star) into warped space-time and trapping light so that it cannot escape (that's why they're "black"). Black holes give insight into higher dimensions and wormholes -- those theoretical tunnels that link one part of the universe to another and serve as the central plot device in 'Interstellar.'
But can black holes go further? Can they give us insight into how the universe began, and what lies in the far future? Can black holes connect to other universes? We can never see them but the "light" of black holes brings us "closer to truth."
Some say science can only answer "How questions," not "Why questions." "Why" is the domain of philosophy. So what's the philosophy of 'Interstellar'? What is it about a universe that features black holes and perhaps extra dimensions and wormholes? What does it mean, if anything, that black holes help structure galaxies such that stars and planets are stable for billions of years? What does it mean, if anything, that a universe with black holes is congenial to life and mind?
"Some people have speculated that there's only one way that things could work, because there's only one manner in which all the fundamental physical laws could hang together in a logical, self-consistent way," Kip says. "But there is considerable evidence in the last decade or two that's not the case."
Here are five possibilities:
- There is no meaning. The universe, as Bertram Russell put it, "is just there, and that's all." Reality is a "brute fact" with no explanation.
- There is "Only One Way" that the laws of nature can be -- the so-called "Theory of Everything." (Cosmologist Max Tegmark suggests reality is mathematical.)
- There are multiple universes, perhaps an infinite number of universes, so that anything that can happen must happen, including us. Because only if we exist can we ask why we exist ("selection bias"). We think we are special when we are not.
- There is a "ground of being" that is a "supreme conscious being" from which all being comes -- perhaps the personal God of Abrahamic religions (Judaism, Christianity, Islam), perhaps the cosmic consciousness of Eastern religions.
- There is a "ground of being" that drives (or is) a kind of teleology in reality (which the atheistic philosopher Thomas Nagel suggests), an impersonal directionality in the universe that reflects the foundations of reality. (The atheistic physicist Paul Davies suggests that the universe is "about" something. The philosopher John Leslie suggests that "value" is fundamental.)
I asked Kip to reflect on a reality that features black holes, wormholes, extra dimensions and time travel.
"I have no great wisdom on this," he said. Maybe, I thought, that's the greatest wisdom.
So while I admire the science of 'Interstellar,' I appreciate even more how it provokes us to ask the "Big Why Question." Why is the universe like this?
Robert Lawrence Kuhn is the creator, writer and host of Closer To Truth, the public television series and website archive of over 4,000 videos of leading scientist and philosophers.