European astrophysicist Sunny Vagnozzi, of the University of Trento and Cambridge University, alongside Israeli-American researcher Avi Loeb, of Harvard University, today published a (potentially) landmark research paper indicating that everything we think we know about the universe’s origins could be completely wrong. According to their work, the Big Bang was more of a Big Bounce. Their paper details a scenario wherein our universe, as we observe it, is merely the result of a previous cosmological phase ending, and a new one beginning. To test their theory, the duo is proposing searching deeper into the universe’s background radiation than we ever have in order to find primordial heat signatures that may give us a clearer view of what happened right after the Big Bang. If they’re able to confirm their suspicions, we may be able to finally understand how previously inexplicable features of the cosmos such as dark energy and timespace warping actually work. Finding out the ultimate truth concerning our universe’s origin could also revolutionize our understanding of what a “universe” actually is. Current theories surrounding the moments directly after the Big Bang lend support to the idea of a “multiverse” where various pockets of massive inflation and gravitational wells could support a cosmological paradigm full of infinite universes. But a model where the Big Bounce theory was demonstrated would indicate a smoother, more operationally simple universe.
Big Bang, rapid expansion
The long and short of the situation involves something called the Big Bang inflation theory, a hypothesis predicting a period of massive expansion directly after the Big Bang occurred. Unfortunately, due to the physical limitation of how far light can travel over a given period of time, the Big Bang happened further back in the universe’s history than we’re able to ‘see.’ Back in 2014, however, a team of physicists performing a study on the cosmic microwave background (CMB) believed they’d come across data that confirmed the inflation theory. Loeb himself commented on the discovery in an article for Space.com, though he wasn’t involved in that particular study. According to him, at the time, if the Big Bang inflationary theory were to actually be confirmed, “it would be the most important discovery since the discovery, I think, that the expansion of the universe is accelerating.” A lot can change in eight years. Today, Vagnozzi and Loeb published research which strongly indicates the 2014 interpretation was wrong. Called “The Challenge of Ruling Out Inflation via the Primordial Graviton Background,” the new paper details a litany of problems with the rapid inflation theory. It also lays out some very interesting speculation into what actually happened in the early moments of our universe and, perhaps most intriguing, it describes what may have happened before the Big Bang. The authors take great care to frame the period of massive, rapid inflation that the current Big Bang theory encompasses as being part of a non-falsifiable hypothesis. In science parlance, this means it can’t be described as part of a working model of the universe, it’s merely one possible paradigm that can be imagined.
Big Bounce, better science
Making falsifiable assumptions is crucial to understanding physics at the grand scale. For example, scientists believe in the theory of gravity because it can be falsified: if you jump up in the air on Earth, you fall back down. In a spaceship removed from the planet’s gravitational field, you keep going until you bump into something with a mass great enough to stop you. According to opponents of the Big Bang inflationary theory, it can’t be falsified. But Vagnozzi and Loeb believe they have a solution that could answer all of the same questions that the theory does, without the need for the rapid expansion period, while also meeting the requirements of the scientific method by being falsifiable. Unfortunately, their idea involves using futuristic radiation detectors built on technology that doesn’t currently exist. So, to sum up, they’ve theoretically debunked the Big Bang theory as it currently stands by providing an alternative theory that, currently, isn’t much more testable than the old one. It’ll be interesting to see what kind of responses the paper gets from physicists who are still on the inflationary theory bandwagon. But, in the meantime, it appears as though Vanozzi and Loeb have come up with a much more elegant, simple solution to many of the universe’s biggest mysteries than the convoluted status quo. Personally, I like the idea of a Big Bounce instead of a Big Bang. As the band Semisonic put it in their hit song Closing Time, “every new beginning comes from some other beginning’s end.”
