Philosophy and the physical sciences have a long and interesting past spanning the entirety of human history. Philosophers have played the role of logically deducing the existence of certain physical phenomena that were untestable. Physical scientists have then either empirically confirmed or refuted the philosophical speculation proposed when the necessary technology and/or method were developed.
Sometimes the philosophical speculations failed to describe the nature of reality, like the Ancient Greek proposition that the heavens were composed of a fifth element: aether . However, on several occasions, the philosophical speculations turned out to be quite exact. For example, in the 4th century B.C.E. philosopher Democritus deduced that the universe was composed of indivisible units of matter known as "atoms." This belief was substantiated over 2,000 years later by the theoretical physicist Albert Einstein (you may have heard of him).
A similarly impressive academic partnership manifested when the Renaissance philosopher Giordano Bruno read the On the Revolutions of Heavenly Spheres by astronomer Nicholas Copernicus. Bruno found Copernicus's heliocentric model of the solar system ground breaking (which it was), and logically deduced that all stars in the night sky were fundamentally similar to our own Sun, and that they had worlds gravitationally bound to them. He famously stated that:
This space we declare to be infinite, since neither reason, convenience, possibility, sense-perception nor nature assign to it a limit. In it are an infinity of worlds of the same kind as our own.
Of course, we now know that Bruno was more or less right. Most stars seem to exist as systems with at least one exoplanet.
In the modern world some believe that this ancient relationship between philosophy and the physical sciences is dead, or dying, or functionally redundant. But I most certainly disagree. Last week I had a chance to meet with philosopher (and systems theorist) Clément Vidal (@clemvidal). Vidal has pointed out that there are certain binary star systems that astrophysicists have had difficulty explaining with conventional astrophysical models. These binaries are semi-detatched stars that exhibit an energy flow that is irregular, but not out of control. Vidal argues that instead of an astrophysical model, we need an astrobiological model to describe these strange systems.
In essence Vidal is claiming that these systems are not typical binary stars, but rather civilizations that have advanced well passed a Type 1 civilization on the Kardashev scale and are now actively feeding on their parent star. He calls these hypothetical civilizations starivores. And if he is right... then there are approximately 2,000 known starivores in our galaxy alone.
Surely this idea is worthy of scientific attention and empirical testing. Democritus's speculation was tested after the introduction of the special theory of relativity. Bruno's speculation was tested as our telescope technology improved. Is there any theoretical model or technology we could use today that could validate or refute Vidal's speculation?
Perhaps, the necessary test is related to understanding the nature of the binary systems "metabolism." Metabolism is one of the fundamental and necessary conditions for complex living systems because it allows them to draw and sustain order from the surrounding non-living chaos. So if these binary systems are actually intelligent civilizations feeding on their parent star then we should expect a degree of energy flow control that cannot be described by the laws of physics alone.
This idea may come as a shock. Over the past 50 years scientists have been disappointed by data indicating that we are alone in the Milky Way. Physicists like Max Tegmark have even gone so far as to suggest that we are the first intelligent civilization to arise in the entire universe. And he might be right... but he might be very wrong as well.
Major breakthroughs in the sciences can come from ideas that at first seem bizarre... even impossible. But the universe has also proved to be stranger than we ever imagined. In my opinion Clément Vidal has called our attention to an interesting phenomenon that our current theories cannot describe fully. I strongly suggest reading his Ph.D. thesis discussing the possibility of starivores (Chapter 9 -- PDF here). And if you are a researcher interested in putting his speculation to the test, the Evo Devo Universe community has just announced the creation of the High Energy Astrobiology Prize. The community is interested in receiving a research study that can either positively or negatively test the starivore hypothesis.
I'm interested to see what we discover!