How did the Early Universe Look Like? By Katherine Lightwood

How did the Early Universe Look Like?

By Katherine Lightwood

Today, I was doing something really crazy and you can say non-sensical. Now, let me tell you how. As you might know, I am studying graphic designing but today when everyone left the class, I started to doodle a few equations from Heisenberg's uncertainty principle article I read recently, out of blue.

And you should know, I am a huge huge nerd about the whole quantum physics and astronomy. So, that's what was happening, I was nerding out when I should be busy focusing on making my designs and practicing.Now, that's a kind of procrastination and a really weird one. So, as I was doodling, I was thinking about what might have happened to the universe just after the big bang. And after a bit of research and insights, I found really amazing facts which I want to share with you all.

This is the earliest photo of our universe. And it shows the whole universe as it is when it was just 380,000 years old.
Ok, that doesn't sound very young for an early photo, but if we consider the universe today to be an eighty-years old person, then that image is equivalent to a baby pic taken only 19 hours after birth. So pretty early right...?

But why can't we get a photo from an earlier time than that? Well!! The problem is that the universe before 380,000 years after the big bang was so hot, that all the matter in it, all these protons and electrons were in a state of plasma. They were all flying all over the place and any light passing through there would get scattered or absorbed.

So, the whole universe was basically opaque. The light couldn't travel anywhere, until after 380,000 years when the universe has expanded and cooled enough for the protons and electrons to get together and form hydrogen atoms, the clear gas. So finally after bouncing around after 380,000 years like pinballs, these photons could finally travel out through space. The whole lifetime of our universe, these photons were traveling through space, not hitting anything until recently. And that's how we got this photo of the baby universe.

Now, of course over that time our universe expanded a lot. So, those photons which started out as ultraviolet or visible radiation, blue light, ended up as microwaves by the time it got to us. They expanded along with the universe. That's why we can't see the earliest light of our universe, but we can detect it with the microwave telescope.
These microwaves are actually found by accident.

From this baby photo of the universe, we found out that our early universe had little hot and cold spots. And those are so important for our existence because they show that the early universe was actually a bit lumpy. There were places with slightly higher density and places with slightly lower density.

And that's incredibly important because those places of higher density will gravitationally pull together, the matter around them clumping into stars, galaxies and the structures that we are part of. I mean without a little bit of non-conformity we couldn't be here.

Now, you might ask where do these cosmic lumps come from? Well!! they seem to be a signature of quantum fluctuations, or it is the idea that we are made of quantum fields and it's impossible to keep this quantum fields perfectly still. They were always varying and bubbling up, like particles popping in and out of existence. Heisenberg's uncertainty (my most favorite theory) principle says that we cannot keep the uncertainty and energy down to absolute zero. Which means there is always going to be some matter appearing and disappearing.

And that seemed to be what created the lumpiness in the universe that we can see. And it is that which give rise to all these major structures like galaxies. So, we should be thankful for this kind of crazy fluctuation because without it we couldn't be here.

So, that was my thought of the day. To see more posts like this make sure to visit our main page. And do not forget to visit our institute's page to know more about graphic design, 3D, animation courses and other awesome stuff. Till then good day to you.

Katherine Lightwood