A physicist at the University of California, James Scargill, has recently calculated that life really could exist in a 2D universe. Wanting to test the anthropic principle that universes can’t exist if there is no life within to observe them, Scargill examined the ideal of life in ‘2+1 dimensions’, where +1 represented the dimension of time.
His paper suggests that ‘there are two main arguments levelled against the possibility of life in 2+1 dimensions: the lack of local gravitational force and Newtonian limit in 3D general relativity, and the claim that the restriction to a planar topology means that the possibilities are “too simply” for life to exist’. The conclusions of his findings have significant implications both for the physics and the philosophy of living outside the ‘3+1 dimensions’ which humans are used to.
Scargill hypothesises that, theoretically, a scalar gravitational field could exist in two dimensions, allowing for gravity and hence cosmology in a 2D universe. For life to emerge, there must be a certain level of complexity, ‘which in this case can be symbolised with neural networks’. Because our highly complex brains exist in 3D, we might initially think a neural network couldn't work in only two dimensions. However, Scargill demonstrates that ‘certain types of planar, two-dimensional graphs share properties with biological neural networks we find in life’. Additionally, such graphs can also be combined in ways resembling the modular function of neural networks, even exhibiting ‘small-world properties’, where a complex network can be crossed in a small number of steps. Therefore, this suggests that such types of universes could support life.
Upon assessing Scargill’s proposition, the MIT Technology Review said: ‘Physicists and philosophers have long claimed that life can form only in a universe like ours, with three dimensions of space and one of time. That thinking may need to be revised’.
Students interested in applying for Physics or Philosophy can further explore this newly put forth theory and its conclusions, speculating on the constructs of space and time and the implications of such a hypothesis.