Page 300 - AWSAR 2.0

276 || AWSAR Awarded Popular Science Stories - 2019
molecules towards them. Nonetheless, there’s one winner the inner water molecule, which hold its surface brethren with such strength and love than the foreign air molecules. So, the surface water molecules behave as if a thin elastic cover is holding together the water droplets, accurately playing out the motto ‘United we stand, divided we fall’.
But wait, why are you only talking about water drops?
I am sure you have seen oil drops sticking to the cooking pan too.
What about the drop of blood oozing out on your finger after the pinch of a doctor’s needle? Gory, but yes, they work the same way too. How small can a drop become ?
How large ?
Are all drops liquid?
Can we have droplets of anything else? Hold your horses!
Let’s start simple. Stripping the already mentioned complicated statement of all adjectives we have:
“Gases in ultracold temperature can form droplets.”
Ultracold temperature is a range of temperature below tens of micro-Kelvin. It’s barely short of -273 degrees Celsius. For comparison, the coldest recorded natural temperature on Earth is approximately -90 degree Celsius. But after rapid technical advancements in cooling methods during the 1980s, in several laboratories, including some in our country, it has become possible to cool gases of atoms to such ultralow temperatures. What it really means is that the atoms become awfully slow, because more jittering around represents more energy and, thereby, higher temperature. Unsurprisingly, it has opened a whole new world for scientists to fixate on. And one such fixation has led to the discovery of
droplets of gas. But there are a lot of nuances to it, let’s dig in.
“Bosonic gases in ultracold temperature can form quantum droplets.”
The water droplets we talked about earlier were large in size with unimaginably high number of molecules. These are classical droplets that we encounter with naked eyes. In contrast, the quantum droplets are microscopically tiny consisting of a few thousand atoms in it. Anything ‘quantum’ in physics is often accompanied by tiny substances and this
intriguing phenomenon where it becomes extremely hard to identify between whether it is a wave or a particle. An atom becomes a fuzzy combination of a particle and also a wave carrying both of their nature. The atoms no more resemble point like particles but become
Take a deep breath and mind to be blown away. Yes, there exists droplets of gas too! What? Yes. How? Strongly dipolar bosonic gases in ultracold temperature can form quantum droplets. Wow. I didn’t understand anything but it sounds ultracool!
prepare your
The water droplets we talked about earlier were large in size with unimaginably high number of molecules. These are classical droplets that we encounter with naked eyes. In contrast, the quantum droplets are microscopically tiny consisting of a few thousand atoms in it.
Don’t worry, we shall
decipher the complex sentence
word by word. Before we do
that, you pause and think, why
formation of a gas droplet is
surprising at all. Imagine a
liquid droplet vs a gas droplet.
Left alone, the liquid droplet-
which has to be a denser object
will remain a droplet because of
its surface tension, while the gas atoms with its lower density will simply disperse. This is the key point, how to balance this dispersion of the gas so that the gas droplet continues to remain as a droplet, especially without any container to hold it?