Today, while listening to the crisis prophet Nouriel Roubini, I noticed—perhaps with a quiet sense of vindication—that he was using exactly the same analogy I often reach for when discussing economic recovery.
Roubini was explaining why economies that slipped into recession during the 2008 crisis, despite managing to emerge for a time, ultimately failed to sustain recovery. The reason, he argued, was straightforward: they never reached a critical growth rate. Without crossing that threshold, they were destined to slide back into contraction. To make the point, he invoked an aviation metaphor: stall.
Strictly speaking, stall is not a perfect analogy—it depends not only on speed but also on angle of attack. But correcting a world-famous prophet of crises felt unnecessary. Besides, since gravity was clearly what he had in mind, the metaphor could be forgiven.
Neoclassical economic theory—most notably the Solow–Swan Growth Model— has long suggested that economies tend, sooner or later, toward a steady state, and possibly toward decline. Escaping that fate requires hitting a critical rate of labor-force growth and/or technological progress.
What practice—and Roubini—suggest instead is something more unsettling: it is not only labor that needs critical mass. The economy itself requires a minimum growth speed, whether emerging from recession or operating in so-called normal times. Fail to reach it, and the system begins to collapse inward. We are already seeing early signs of this. The coming months may make it impossible to ignore.
I have said before that I am among those who believe the laws of nature apply to the social sciences as well—or at the very least, that they help illuminate phenomena such as religion, morality, and social dynamics.
The situation described above bears an uncomfortable resemblance to the critical expansion rate of the universe.
Contrary to Albert Einstein’s intuition of a static universe, Russian astrophysicist Alexander Friedmann, working within general relativity, demonstrated that the universe is expanding. (Not to be confused with Milton Friedman, one of many economists who merely share the surname.)
According to cosmological calculations—and according to a certain subset of believers who accept scientific claims without fully understanding them, then rush to locate them in sacred texts—the universe appears to be expanding at a rate eerily close to the minimum required to avoid collapsing back onto itself. Of course, this rate cannot be measured with precision. Doing so would require knowing the total amount of matter in the universe—an impossible task, given dark matter, black holes, and other forms of mass that refuse to emit light.
If the universe’s expansion speed is insufficient to counteract the gravitational force first described by Newton, that expansion will gradually slow. After a brief moment of balance, the universe would begin to collapse inward—toward what Stephen Hawking called a singularity.
At that point, whether time continues forward or begins to run backward becomes an open question. If time were to reverse, humanity would indeed rise again from the earth, just as described in the Qur’an. But the miracle would not end there. Even the expressions we casually hurl at one another today—phrases better left untranslated—would suddenly acquire a disturbingly literal meaning.