TImages from the James Webb Telescope – described by NASA as a “time machine” because light takes billions of years to reach us – raise the question: Will it ever be possible to see the big bang itself? I asked Dr. Matthew Bothwell, a general astronomer at the University of Cambridge.
Why is the James Webb telescope so good?
First, it’s infrared. Firefighters wear infrared goggles as it helps them see through smoke and dust, and stars are forming behind a lot of smoke and dust. Also, and this is a little technical, the light from far space is redshifted. This is because, as the universe grows and light travels through it, the light expands and becomes redder. Finally, the telescope is really big.
If the universe is expanding, why not the Earth? Why don’t I stretch? Or am I? Oh my God, I thought I felt weird today.
We are held together by electrostatic forces, which basically means that atoms – which we are all made of – are like sticking together. Expansion can only gain a foothold when those forces or gravity are really weak. This means the distances between galaxies.
Oh, the magnificence of the little atoms stuck together. So where does the universe expand? From? Will he be in the center?
There is no center of the universe. It is a mistake to think of space and time as a box in which the universe sits. Space and time are properties within the universe. The Big Bang created space. Every point in the universe was where the Big Bang occurred.
Could a telescope ever see it?
I’m afraid it does. From a cosmological perspective, light is very slow. It takes light eight minutes to reach us from the sun, so when we look at the sun, we’ve been looking at it for eight minutes. If you look a million light years away, you receive messages from a million years in the past. At the time of the Big Bang, all matter and things in the universe were compressed into a small volume. It was very dense, and it was opaque. Only as the universe grew did the density decrease and light could travel through it.
So if the space is a pair of tights, you can see through thembut, before you stretch, it’s too dark to see anything?
Why is seeing the early universe important?
When you try to solve difficult problems, you end up inventing things. A group in Cambridge uses millions of images to search for faint galaxies. It turns out that the technology they developed is just what you need to find tumors that you can’t see with the eye. It improves cancer detection rates.
Fabulous! I don’t usually like talking about space; It makes me anxious seeing how diminished and meaningless we are all of us.
There is a term for this – cosmic vertigo. I feel it too, but it can be a positive. This means that anything bad in the world is meaningless in cosmological terms.
This makes it worse! All the pain we inflict on each other for nothing. But that cancer story was beautiful – how do we reflect the universe in our bodies.
Oh, 100%. When we look at galaxies very far away, we see the same components that we made. Carbon, hydrogen and iron. It’s like Max Ehrmann’s poem: “You are the son of the universe, no less than trees and stars.”