this post was submitted on 23 Sep 2024
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[–] mholiv 22 points 2 months ago (4 children)

A drop in the bucket isn’t event close to a good understanding of how big space is. A satellite in the ocean is grossly misleading when it comes to the scope of space.

Maybe a single O2 molecule in the ocean might be closer but even then that’s not even close to the scope of space.

Space is big. So big that the light cone of our “pollution” can’t physically interact with most of it even if we did our best to “pollute” as much as we can and some alien species did their best to find that “pollution”. Space is so big that physics dictate the impossibility of our “pollution” interacting with most of space.

Fun fact this is why the chance of aliens visiting us here on earth is basically 0.

You can’t use earth scale thinking, that’s how big space is.

This all being said we should do our best to not pollute the earth. We should use earth scale thinking when it comes to earth.

[–] [email protected] 5 points 2 months ago

Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space.

Douglas Adams

[–] NotMyOldRedditName 3 points 2 months ago* (last edited 2 months ago)

I've always enjoyed this video to give a perspective on size

https://youtu.be/i93Z7zljQ7I

I usually increase playback speed, it's a bit slow at start.

[–] [email protected] 3 points 2 months ago* (last edited 2 months ago) (1 children)

There's about 4.6*10^46 molecules in the ocean. There are about 8.5*10^47 cubic meters in a cubic light-year

Surprisingly close orders of magnitude

For reference, the closest next star system is 4.25 light years away. The diameter of our Galaxy is about 105 700 light years, with a thickness of about 1000 light years (much less than the diameter, since our Galaxy lies on a plane)

[–] mholiv 2 points 2 months ago (1 children)

Huh. That’s crazy. And that’s just one cubic light year.

Now if we multiply that cubic light year to match the volume of space we have a similar comparison. Infinite oceans to sift through for a single molecule.

[–] [email protected] 1 points 2 months ago (2 children)

"Space" as a volume is probably infinite, but even just talking our local stellar neighborhood or even just the solar system and space is already ridiculously more empty and big than anything you could compare to on earth. With I guess the possible exception of high-precision vacuums in laboratories.

[–] mholiv 1 points 2 months ago

Thus the infinite oceans to sift through. 😉

[–] [email protected] 2 points 2 months ago (1 children)

Fun fact this is why the chance of aliens visiting us here on earth is basically 0.

You can’t use earth scale thinking, that’s how big space is.

But that is earth scale thinking. You know, in a "things heavier than air can't fly" way.

[–] mholiv 2 points 2 months ago* (last edited 2 months ago) (1 children)

It’s more of a “the speed of light is the cosmic speed limit” way of thinking. If you feel aliens are visiting earth you do you.

[–] [email protected] 1 points 2 months ago (1 children)

That's what i meant. Even our civilization, with our limited understanding of physics, can think of theoretical workarounds.

Dunno if aliens are on earth. But that argument against it, is only guesstimating.

[–] mholiv 1 points 2 months ago (1 children)

Fair. But that’s not really earth scale thinking in my book. It’s more our best understanding based on what we know.

I know of these theoretical work arounds. They’re more mathematical models that say if such a thing as negative mass exists, then we might be able to go faster than the speed of light. Issue is that the model does nothing to show that negative mass exists.

That and everything we know shows that it does not exist. If it did I would be incredibly happy. It’s just wishful hoping at this point though. We don’t even have a model or theory that shows how negative mass could exist. We only have theories that show what could happen if it did exist.

It’s like saying hm we know how F=m*a works. What could happen if we set m to a negative number? Yah in the math we can but that does not mean we can in reality.

[–] [email protected] 1 points 2 months ago

Sure, yeah. My point was more, that we are only starting to understand things and have a limited horizon. And especially the last few years have shown, that our models from the last century might need adjustments or be entirely wrong.