News, Philosophy, Physics

Black holes and all that

Picture from cited Nature article

I intend to start some posting to this site, and science news is a good place to start. For science entangles the ordinary everyday course of our lives with inconceivably exotic and almost unimaginable events of our vast yet comprehensible universe. The collision of two supermassive black holes recently detected by the LIGO/VIRGO collaboration of gravitational wave astronomy made news articles in both Nature and Science and, additionally, had two NewYork Times articles( 1 and 2) about it.

The new era of gravitational wave astronomy continues to astound.1 Interestingly, in my physics work, I study the entirely opposite extreme–the very “soft” collisions of extremely non-massive objects, that is, individual atoms moving very slowly according to the rules of quantum mechanics. Collisions tell us a lot about the universe on all scales from atoms to galaxies. There is a unity to it all. The LIGO gravitational wave detector is also a fascinating story–how they could build such a fantastically sensitive instrument that could detect the incredibly faint ripples in space-time from so far away: the LIGO detector measures gravitationally triggered motion of less than the width of a single atomic nucleus, and yet LIGO can do it. I will save that story of laser interferometry for another time.

The first verified detection of a gravitational event by LIGO was nearly 5 years ago on Sept. 14, 2015. Such gravitational waves have given humanity its first view of the distant universe that is not based on electromagnetic radiation.2 So far there have been a number of such gravitational events (at least several dozen) detected by LIGO and similar observatories, including a merger of two neutron stars. Seeing such events tells us more about the cosmos and its exotic objects than we could learn from electromagnetic radiation alone. Astronomy has advanced massively since the days of Copernicus, Kepler, and Galileo.

The Science article is entitled “Most massive black hole merger yet puzzles astronomers.” Science in fact delivers to us many puzzles, not the least of which is that we can understand them enough to know that they are puzzles. If you follow the logic of the Science article, you can see how scientists think. There is a measured event that is decidedly odd, and then one needs to come up with an explanation on how to understand it. Given the conceptual framework and quantitative mathematics of Einstein’s theory of general relativity, and a knowledge of how the instrument works, the “best” way for scientists to interpret what the instrument measured is that it was the very fast transient signal of ripples in space-time caused by the merger of supermassive black holes. What in the world does that mean?

There are lots of fascinating avenues to explore here on what do data actually imply. There are never simple “facts” about the world. A “fact” is something we make (it comes from the Latin verb facio, meaning “I make” or “I construct”), although it is most certainly never simply “subjective” either. Another way to say this is that all “facts” are theory-laden, that is, they need a system of meaning that tells us how to make sense of the context out of which the “fact” emerges. No “fact” is simply “bare,” uninterpreted. It only exists within a web of meaning already given to us by our socially embedded being in the world. That embedding is, in particular, in the world of language, which tells us what to say about things. If you pause to think about it, the fact that human beings use language and understand one another is one of the most remarkable things about the world.3

While most scientists will affirm that the world is “really there,” (we do not “make it up” out of our imaginations), yet we bring something of our own embedded modes of thinking to what we ascribe to what is “really there.” Consequently, physics is inescapably imaginative in the best and most realistic sense of the word. All language is social, since the human being is a social animal (and thus of necessity a “political” animal, since humans live together in the “polis“, city), as Aristotle taught us long ago. Language tells us what to say about both ordinary and extraordinary things. Einstein’s mathematics of general relativity provides a language to teach us what to say about black holes in order to explain odd ripples in space-time seen by very complex instruments that took a major social and political effort to construct (the LIGO instrument is very expensive to build and run). There is a sheer joy in discovery. Scientists know that. At some level they must also know we are meant for it.

In the end, everything is simple and nothing is simple, both at the same time. This completes the philosophy lesson for the day.



1. Two article in Physics, a publication of the American Physical Society, explains more about the puzzle regarding black hole masses created by the new observation and about the promise of future gravitational wave observatories.

2. We know electromagnetic radiation as “light,” but the entire range of possible wavelengths of “light” span magnitudes far beyond those of ordinary visible light; for example, infrared or radio frequency radiation on the longer wavelength end, or ultraviolet or x-ray radiation on the shorter wavelength end. Much modern astrophysics is based on measuring the radiation coming to us in these various ranges of wavelengths.

3. Philosopher Martin Heidegger called language the “house of being” (in the opening paragraph of his Letter on Humanism (1946): “Die Sprache ist das Haus des Seins.” ). All there is touches us in one way or another through language, even though we all know the inadequacy of language to say everything we want to say. Being and language belong together, are somehow made for one another. Otherwise, how could the Gospel of John open with these remarkable words: “In the beginning was the Word …”? “Beginning” here means “source,” “origin,” “ground.” See my poem, “The hidden work of being.” There is indeed a unity to all things, hidden in the ordinary use of language.