Written as if for publication on Wired.com
Regular Guardian contributor and visiting fellow at the University of Sussex John Gribbin has made his mark in history for a number of reasons, including his pioneering work on measuring the size of galaxies. In between experimental work such as this and other speculations (such as the idea of using iron to fertilise the oceans with plankton to combat climate change), Gribbin somehow manages to find the time to write a book or two. Famous for his unique ability to explain complex theoretical physics in a simple and digestible manner, Gribbin has covered everything from quantum mechanics to time-travel. His last book The Universe: A Biography has been available for over a year and now his next book is due for release.
Gribbin has revealed that he is currently working on a book detailing the cutting-edge science surrounding Multiverses. John suggests “There may be other regions of space-time which are somehow disconnected from us, they may be in other dimensions, perhaps you can access them through black holes”. This theory is of course nothing entirely new, with ancient Hindu scriptures detailing multiple universes dating hundreds of years. What this new book will hopefully reveal however, are the scientific processes by which modern physicists are beginning to rethink the nature of the cosmos. Gribbin is keen to stress that the concept of multiple universes is not merely confined to speculation and could well have practical effects upon the way in which we understand quantum behaviour.
Our current understanding of quantum mechanics can be explained with the ‘Schrodinger’s Cat’ model. This thought experiment involves a cat in a box, which can be either dead or alive. When the cat is examined it can be established whether the cat is alive or not. The act of observation then determines whether the cat is indeed dead, fixing the state of the cat. Before the observation takes place however, the cat is deemed to be both dead and alive simultaneously. This seemingly paradoxical notion is how scientists have shown quantum behaviour to occur, with particles existing in multiple states at the same time until observation occurs. Gribbin’s new book will elaborate upon physicist Hugh Everett and be one of the first to explore the idea that particles can exist in multiple states, but in different universes. So Schrodinger’s cat may be alive and well in our own universe but unfortunately deceased in some other dimension. Gribbin concludes that “Schrodinger’s cat would be both dead and alive... requiring a full splitting of the universe at the point of observation”.
Gribbin explains that another example of quantum multiverse theory is evident through experimentation. In a variation upon the famous double slit experiment, scientists have beamed a single photon onto a sheet of material featuring two slits for the particle to travel through. Surprisingly, when the other side of the sheet is observed, an interference pattern appears. This can only be produced by the photon somehow entering both of the slits and converging back into a single particle on the other side. The very concept of this has shattered all understanding of quantum theory and can perhaps only be explained by the multiverse theory. “What this branching and rejoining idea suggests is that two universes exist while this is going on. In one universe it goes through one hole, while in the second universe it goes through the other hole. On the other side of the screen the two universes join back together, and that’s what makes the interference pattern” claims Gribbin.
Our knowledge of quantum theory is constantly challenged and it seems quantum scientists know no limits to their speculation and experimentation. If Gribbin’s writing skill and investigative nature are anything like they have been for his last few releases, then it looks like we are going to be treated to a myriad of fantastic new ideas come 2009.