Watching this video about the Large Hadron Collider (a particle accelerator under construction at CERN), I was reminded of something I was wondering about a few weeks ago. People talk about the universe being the size of a grain of sand, or the size of a marble, in the moments immediately following the big bang. That seems comprehensible enough, but there is a fundamental problem with the analogy. The marble sized thing isn’t just all the mass in the universe, expanding into space that existed prior to the ‘explosion.’ Instead, space and time were supposedly unfurling simultaneously.
The big question, then, is how it can be said that it was expanding at all? If there was nothing to expand into, how is this process of explosion something that is comprehensible, as such? To imagine it requires a perspective where the camera is outside our universe, an idea that invalidates the notion that the big bang was the origin of our universe. And, even if our universe is embedded in a higher dimensional space, the emergence of our lower-dimensional realm still requires some explanation. I wonder if it will ever become an object of knowledge for us: both as a species with a certain amount of information about how the universe works – verified through repeated experiments and predictive power – and as a collection of individuals who almost never know more than a tiny fraction of what all people know as a collective.
The video is a bit over-hyped, as well as a transparent attempt to defend spending a great deal of money on pure research, but perhaps it will interest some people regardless. Some of the prospects associated with the LHC – such as looking for evidence of supersymmetry or investigating the nature of gravity – are very exciting indeed, from the perspective of advancing our basic understanding about the nature of matter, and the kinds of interaction that take place in our universe.