“NO QUESTION is more sublime than why there is a Universe: why there is anything rather than nothing,” philosopher Derek Parfit .
Sublime it might be, but the question has traditionally exercised philosophers and theologians. Creation myths, a feature of many cultures, satisfied a deep-seated need for meaning and narrative drive in our existence (see “Why do we exist?“). Scientific thought, insofar as it paid attention to such matters, assumed the cosmos had always been there in an eternal, unchanging state.
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Then came the greatest scientific revelation of the past century, arguably of all time: what came to be known as the big bang.
Its seeds were sown by Albert Einstein with general relativity, his theory of gravity, back in 1915, and by Edwin Hubble and others in the 1920s. Their astronomical measurements showed that far-off galaxies were receding from us, as if the universe were expanding.
As late as the 1940s, physicists including Hermann Bondi, Thomas Gold and Fred Hoyle were explaining these observations in terms of an eternal, steady state universe that expanded through the continuous creation of matter. Today, we can cross this possibility off the list. “That’s not a stable state for a universe that is structured in the way we see ours is,” says cosmologist Katie Mack at North Carolina State University.
That is partly because it is hard to square with the way gravity works, only pulling inwards, not pushing outwards. But it is mainly down to the discovery of the cosmic microwave background radiation in the 1960s. This all-pervasive radiation was exactly what you would expect to see if everything began as a tiny, dense glob of matter and energy that has since expanded and cooled to become the universe we see.
Suddenly, the “why something rather than nothing?” ball was firmly in science’s court. What exactly happened at the instant of the big bang, now pinpointed to some 13.8 billion years ago?
These days, cosmologists don’t automatically think of it as a point when everything came into being from nothing, says Mack. Indeed, while we are confident we have got the story of cosmic evolution broadly right back until that point, the big bang “singularity” is singularly problematic. It represents the point at which general relativity’s equations become plagued with ungovernable infinites, and break down. In this sense, “the big bang is understood as not a fact, but a problem”, says cosmologist , Germany. “It’s a pathology of our theories.”
With no clear explanation of what the big bang was, we are pretty hamstrung in explaining why it was. There is no shortage of ideas: that our observable universe is just one of many budding off one another in an eternally inflating multiverse (see “Why is the universe just right for life?”), for example, or that a pre-existing universe contracted to a small, but not infinitesimal, size, before bouncing outwards again. Oriti is developing an idea in which the big bang singularity represents a “phase change” where space and time, and the rules of geometry that govern our universe, emerged from some non-geometric netherworld.
But in explaining how our something sprung from something else, these resolutions just raise the question of why those other things existed. Perhaps that is telling us something about what it means to seek the origins of everything in the first place. The truly sublime aspect of asking this question isn’t so much in finding the answer, but in the otherworldly journey it takes our minds on.
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