Imagine yourself immersed in the prelude to creation.


The universe is not. What “is” is hot, dense, shapeless, formless, void — as close to a traditional concept of “nothing” as can be. Then…


The universe explodes into being.


In that micro-instant at the dawn of creation, in that wondrous, incomprehensible cacophony of newly-found existence, how fast does the universe expand?


It may seem like an odd or irrelevant question. Nevertheless, it is a question smack-dab at the raging center of one of the most important debates ever to erupt in the realm of cosmology.


The theory of cosmic inflation postulates that in the millionth of a trillionth of a trillionth of a second following the Big Bang, the universe expanded at an astonishing rate, many times that of the speed of light. If true, this theory offers elegant explanations for some of the most tantalizing mysteries the observable universe contains. Inflation theory is a true behemoth, widely renowned for its importance and potential impact on the way humans view the world.


Cosmic inflation girds itself in picturesque intellectual beauty, but for most of the last few decades the theory was confined to the realm of the, well, theoretical. No longer. On March 17, astrophysicists working with BICEP2 (Background Imaging of Cosmic Extragalactic Polarization), a special telescope in the South Pole, announced that they had measured the presence of gravitational waves, ripples in the fabric of space-time.


Gravitational waves were postulated in 1916 by no less luminous a light than Albert Einstein, who extrapolated their existence from his theory of general relativity. Einstein theorized that bodies moving through the universe would literally bend the fabric of space-time, generating ripples that would then spread outwards, like ringlets from a stone thrown into a pond.


Scientists scouring the heavens for proof of Einstein’s theory faced one major hurdle. Gravitational waves are incredibly difficult to detect. The only event that could hope to produce waves strong enough to be measured by human instruments would have to be something cataclysmic, something incomprehensibly violent — something like a newborn universe expanding at mind-boggling speeds.


Imagine, then, the astonishment and excitement that swept through the scientific community when BICEP2’s researchers announced their results in a dramatic press conference. They claimed to have measured not the actual waves themselves, but rather the waves’ effect on the cosmic microwave background radiation that permeates the entire universe.


According to theory, gravitational waves should polarize this omnipresent echo of creation in a certain way. Evidence of this polarization is exactly what the BICEP2 team claimed to have found. It was a discovery of astounding significance, perhaps the greatest scientific achievement of this generation.


Almost immediately, the results ran into trouble. Physicists tried to replicate BICEP2’s findings, to no avail. The South Pole team was roundly criticized for using incomplete data to make key measurements. A rising chorus of skeptics wondered whether BICEP2 had in fact observed the interaction of cosmic dust with background radiation, a phenomenon that would generate much the same result as gravitational waves. In the memorably snarky words of Washington Post writer Joel Achenbach,

“These doubters say, in effect, that rather than seeing the aftershock of the birth of the universe the scientists have seen only some schmutz in the foreground, as if they needed to clean their eyeglasses.”


For now, the debate remains largely confined to the realm of scientific politics and evaluation. BICEP2’s researches stand by the strength of their findings. The lay of the land is still quite uncertain, and all parties will likely have to wait months for the release of additional data to reach anything resembling a consensus.


All things considered, it is heartening to see such a spirited and lively debate taking place among the leading lights of cosmology and other disciplines. Scientific inquiry demands rigorous intellectual and evidential analysis. The greatest mysteries of the universe deserve nothing less.


Do scientific debates on the origins of the universe spark your interest? Discuss in the comments below or connect with me on Twitter @aa_murph