Before the Big Bang 1 – Loop Quantum Cosmology Explained
What happened before the big bang? It’s one of the most popular questions in astronomy. When the observable universe is smaller than an atom our classical theory of gravity, Einstein’s theory of General Relativity, breaks down and needs to be modified with a theory that can also accommodate the physics of the sub atomic world, quantum mechanics. Armed with a quantum theory of gravity cosmologists may be able to tackle the question of what happened before the big bang. Loop quantum cosmology is considered one of the most promising candidates for such a theory. In this film we interview some of the leading scientists in the field to explain this exciting theoretical development. We ask what happened before the big bang? Is there a multiverse? Why was the entropy of the universe so low in the past? Could the Planck spacecraft anomalies be signs of the pre big bang universe? How do we test these ideas? Should we accept the claims that the universe really has a beginning? In some sections of the film there is CGI animation to help visualise the evolution of the universe. These are for illustrative purposes only and should not be taken too literally. For example, the big bang is not an explosion from a single point and a quantum bridge would not really look like a tunnel; the universe is 4-dimensional, not 2- or even 3-dimensional, so these images are simply to assist the explanation.
All of the video was shot by us on a Sony VG900 full frame video camera. Other images were provided by:
Opening photos: our teacher and friend Roger Wesson (European Southern Observatories)
Eternal inflation animation: Anthony Aguirre & Nina McCurdy (University of Santa Cruz), Joel Primack and Nancy Abrams
Hourglass universe, continuous space time and Big Bang Observer animations: Alex Bennett
Spin foam animation: Thomas Thiemann (FAU Erlangen -Nurnberg), Middle Science Communication (Potsdam), Exozet (Potsdam)
Gamma Ray Burst: European Southern Observatories Black hole simulation: William East (Princeton University)
Thanks to Sabine Hossenfelder at Backreaction blog. Thanks also to Marcus at physicsforums.com
Music is “Shot in the Head” by Moby and is used with permission.
Source material is embedded within the video; click pause to read more details.
The content of the final version of the film was checked and approved by the interviewees. Many thanks to both of them: Abhay Ashtekar (Penn State University) Ivan Aguillo (Cambridge University)