ObservedSimulated
The brain and the cosmic web: a comparison of data, not pictures
A famous pair of images sets a slice of human cerebellum beside a slice of a simulated cosmic web, and they look alike. The look is not the finding. Branching shapes are everywhere in nature, and resemblance alone proves nothing.
What Vazza and Feletti compared were measurements. They took the power spectrum of each network, a standard cosmology tool that records how much structure there is at each scale, and a set of network statistics: how many connections each node has, how clustered the nodes are, and how the connections are spread. Fluctuations in the cerebellum network from 1 micrometer to 0.1 millimeter follow the same progression as matter in the cosmic web from 5 to 500 million light-years, and several network statistics agree closely. Their paper shows the spectra themselves.
A book can only print the two pictures. Here the aim is to show the measurement: an interactive that computes a power spectrum, so you can see what is being compared, is in preparation. Element 7 of A Quest for The Big TOE asks what the shared statistics might mean.
- Paper:
- Vazza and Feletti (2020), “The quantitative comparison between the neuronal network and the cosmic web,” Frontiers in Physics 8. doi.org/10.3389/fphy.2020.525731 (open access, CC BY 4.0)
- Tissue:
- Human cerebellum and cortex, light microscopy. Simulation: Vazza et al. (2019), Astronomy & Astrophysics.
- In the book:
- Figure 7-1, Element 7