Day 5 of ICTS-SSWP '26: Scaling Across Worlds, Breaking Across Barriers
Day 5 of the ICTS-SSWP 20261 began with a session by Dr. K. Sridhar from APU. He asked us to look at the universe through a different lens: dimensions. We started discussing the fundamental constants that we see everywhere, and their units. We extended this to solving a few physics problems - like deriving the radius of Bohr’s orbit - using only dimensional analysis.
We started looked at some common trends across mammals, and noticed very interesting patterns. Take, for instance, when we plotted heartbeats per lifetime vs. average body weight of different mammals, the graph turned out to be a constant line.
We also looked at another example - heat production vs average body weight of different mammals. By using the fundamentals of physics, and a few simpler models, we arrived at a slope of $2/3$ vs. the real-world experimental slope of $3/4$. Given the highly simplified modeling and quick calculations we did in the session, our theoretical estimate came very close to the actual experimental data. This exercise demonstrated how simple physical laws can elegantly approximate complex biological systems.
Another interesting part of this discussion was the question: How does rowing time scale with the number of oarsmen in a boat? As it turns out, the advantage is almost negligible; time $t$ is proportional to $n^{-1/9}$, implying there isn’t much impact on the returns by adding more oarsmen.
Interestingly, the scaling analysis that we carried-out revealed some really unexpected things - in places that seem really unrelated. We looked at infrastructure data from four European countries and found that the slope of number of petrol pumps plotted against a city’s population was nearly the same, $0.85$. Something even more interesting was that this slope of $0.85$ was not just for petrol pumps but also for other infrastructural quantities linked to transport and supply networks like roads, gas lines, electric line, etc.
In the afternoon, we shifted our focus from theoretical modeling to collaboration, to compile our observations and conclusions from the week’s lab sessions. We presented our report to the faculty. We had a very productive discussion and constructive feedback.
The evening, however, took a much more reflective (and necessary) turn as we gathered to discuss the status of women in physics. Prof. Gita Chadha from APU started the session - Women in Physics: Why So Few?. To get the conversation going, we watched a highly controversial promotional video released by the European Commission years ago, originally intended to encourage young girls to pursue STEM fields. The clip sparked an intense debate about the lingering biases in scientific outreach. We talked about how damaging it is when institutional campaigns rely on superficial stereotypes - like high heels, makeup, and lipstick - rather than engaging girls with the actual, thrilling substance of science.
We wrapped up the day by bringing focus back to India, speaking openly about the current situation for women physicists. It was a heavy but necessary end to a day that perfectly bridged the elegance of hard science with the tight-knit community we are building here.