Comment by kadendogthing | Hacker News Reader

Comment by kadendogthing | Hacker News Reader

>Under the influence of dark energy, the cosmos is now doubling in size every 10 billion years — to what end, nobody knows.

It's a simple concept to grasp, but to truly understand I think is something we'll never be able to do. These kind of simple little factoids absolutely blow my mind. They're not new to me, but being reminded me of them kind of forces me to sit back for a second and realize just how irrelevant our planet is.

The entire universe, just doubling. Because it can. And there's apparently nothing stopping it. It's just going to keep going.

Life is maybe only about ~4 billion years old. That's it. Life was able to start up, evolve, and make us. In about 4 billion years. We don't even have an idea about the type of technology that we could use to get out of our own, singular galaxy. In about double that amount of time, the universe will apparently have doubled. Perhaps forming new galaxies, new types of matter, new life and all sorts of non-sense.

Sorry for the rant. But it really is a bit insane to think about.

No, no new galaxies and matter, just more empty space, with the space between us and the further out galaxies expanding so fast that they become inaccessible even at the speed of light, then those only half as far will disappear behind this horizon of reachability, then those even closer, until only the closest few galaxies will be left in an otherwise entirely empty universe.

Even later, space will expand so fast that the gravitational interaction that keeps the milky way (or its successor formed by the merger with Andromeda) will be overcome and every star will be alone in an empty universe, than the stars and planets will be torn apart by the ever faster expanding space, and finally maybe even the atoms and particles from the debris.

We're thirty thousand light years from galactic central point We go round every two hundred million years And our galaxy is only one of millions of billions In this amazing and expanding universe

The universe itself keeps on expanding and expanding In all of the directions it can whiz As fast as it can go, the speed of light you know Twelve million miles a minute and that's the fastest speed there is

So remember when you're feeling very small and insecure How amazingly unlikely is your birth And pray that there's intelligent life somewhere up in space Cause there's bugger-all down here on Earth

> The universe itself keeps on expanding and expanding In all of the directions it can whiz As fast as it can go, the speed of light you know Twelve million miles a minute and that's the fastest speed there is

Faster than that - the universe expands faster than the speed of light, because it's not the matter that is moving away, it is the space itself that grows between.

Sorry for the rant. But it really is a bit insane to think about.

In a time long past, there was a vast cosmic war. A weapon so final and terrifying -- a vacuum catastrophe weapon -- was unleashed, destroying the entire former universe in a colossal inflation of spacetime itself. In its wake, all there remains is a cooling, vast, empty, expanding void, so barren that life has almost no chance to begin and essentially zero chance to meet other life.

>realize just how irrelevant our planet is.

So..what would be a situation where our planet would seem 'relevant'? Maybe if there was only 1 solar system? Or..

What I'm having for breakfast seems important to me, or I could try to 'sit back for a second and realize just how irrelevant my life is'.. But that's not how importance works, or relevance, or meaning. They're relative to something, someone.

p.s. I used to love astronomy when I was a kid - had a big telescope, wanted to be an astronomer - also used to love climbing to the top of trees, tall buildings. Now I mostly prefer not to think that the ground we walk on, is on a rock hurtling through space, which could be destroyed anytime, but has been orbiting a star for billions of years..etc. All that makes me dizzy. '..portions of eternity too great for the eye of man.'

I have the opposite point of view. Far from being irrelevant, our planet and our life here is the only thing that is relevant. Galaxies we will never visit, cosmological phenomena totally beyond our control... none of it matters at all to our lives here and now, except as intellectual curiosities for the few who are interested.

You realize that's what I was saying, right? Maybe I should've spelled it out more.

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