Tag: Jalpa Soni

Hi everyone,

My name is Jalpa and I am a researcher at the university of Gothenburg. I work at the department of Physics, which means I am a physicist. But what is it that I actually do? and more importantly why? Well, physics is behind almost everything we do in our everyday life! All of the technologies, radio, TV, computers, phones or the way we travel around with bikes, cars or planes came into existence because of physics. The very nature of universe can be understood with the laws of Physics. You might have heard the saying that “mathematics is the language of science”, and it’s true, isn’t it? But physics is the heart of science! From looking at stars in the universe to how we “see” things can be understood with Physics. However, today our knowledge has expanded so much that science is branched out in so many fields and subfields. And all these subfields are also being updated everyday, bringing more data. More data means more understanding. More data also means more challenges… and that means more technological developments. One of the recent example is the new iPhones that Apple announced this month. If you have followed, you might already know that their newer models are running on a nanometer size chip – that is one-billionth of a meter – claimed to be the smallest chip for a smartphone ever! That has been possible because physicists have been studying what happens at those scales with matter.

A billionth of a meter! Being able to study something that small is fascinating, right? A few decades ago, that would have been unimaginable, except for science fiction maybe. But today we talk about nanorobots that can go in our bodies and perform medical tasks for us! Technological advances have once again reduced the boundaries inside science and once again interdisciplinary science is becoming more exciting, to use it to improve life in general.

I also work in both biology and physics, occasionally using some chemistry as well as a bit of maths to explain the theory of my experiments. Among my various projects, the main theme is to study small things – of micron size – that is one-millionth of a meter. Specifically, I study the pattern of microorganisms (like bacteria), how they move around in various conditions.

But the effects I study with them are observed even in human scales. (showing some slides with images at this point)

1. For example, look at these penguins! These are emperor penguins, they live in Antarctica. These penguins huddle, gather around and move in large groups. And since it’s very cold environment where they live, they need to keep themselves warm! Look at these nice patterns they create while they move. They lean on the one in front of them and then rotate around in small steps, shifting positions from the outer side to the centre of the circle. This way, they are warm once inside the centre, the newcomers come and join the outside, but eventually everyone gets a chance to move inside for a while at least. The shifting pattern allows that to happen and everybody is happy.
2. Now look at these birds! They make beautiful patterns when they fly around together. As you might already guess, generally migrating birds make such large groups because it’s easier to keep the predators away. Also, it’s easier to hunt this way. In Denmark, they cause the effect of the “black sun” or the “sort sol” as the Danes call it. Every year in spring and autumn, the European starlings migrate from southern Europe to Scandinavia – near baltic sea – to breed. In Denmark, groups can get as big as a million birds and they cover the sun right around sunset to choose their nesting place, causing the “sort sol”.
3. In the ocean, large groups of fish also move in beautiful patterns!
4. Okay, all these patterns are nice to look at! but why are they important? right?
5. Well, look at this. Any of you find it familiar? It’s a scene of a crowd from one of the games, right? Did you know this particular game became a really big deal because of this particular scene? any guesses why? I will give you a hint – it’s the people! The number of people they simulated for this scene is what made the history. Wonder why is a crowd scene in a video game such a big deal? It’s because simulating a crowd of people is a lot more difficult than one would think! Look at this crowd simulation, you can see how it describes the people in a real crowd! There will be much more collisions and much more mingling in a real crowd! And it’s important to make crowd simulations more realistic to improve disaster management, isn’t it? For example, to design proper evacuation protocols in a fire-alarm situations, or for earthquake evacuation protocols. It would be good to be able to design public places accommodating good emergency protocols! Understanding these patterns of nature can help us achieve that on a more efficient manner.
6. And now let’s get back to the small world! At micron scales, look at these bacteria – they behave in nice and familiar looking patterns as well! And it’s important to understand how they move in various environment, like how they spread on a bad slice of bread, or in a rotten fruit, or in our body! Such studies could tell us how to stop the unwanted ones to enter our system and to select the good ones for benefits. Because not all bacteria are bad, some are good for our body, help us digest our food for example.

So, one of my project is related to this. We study bacteria in a complex environment and see how they find their way around it. We put some bacteria and some small particles (around the same size as bacteria but made of silica) together and monitored what happens to the bacteria. As it turns out they make highways, which are reused by the following bacteria, and this way they actually move in longer distances compared to when there are no obstacles. Bacteria alone move in more circular patterns, while in an obstacle environment their circles get bigger! We are trying to understand the mechanism behind this kind of motion and we want to see if that can be used to design artificial robots based on bacterial motion.

Now, I also want to study these things in three dimensions, more realistic! The read world is 3D! So I am building a microscope to do 3D imaging at high speeds to monitor live motions of these microorganisms. It’s called a light-sheet microscope and it looks like this! Not at all like a typical microscope! And this is one of the 3D video I took earlier this week. It’s short, but I think you can see the 3D volume and the motion of particles in 3D.

So, this is what I do! I also work with some other projects and I will talk about them if you are interested. Thank you for listening and feel free to ask any questions!