People were dying en-masse because you had doctors not washing their hands when moving from autopsies to giving birth.

No one was aware about the germs that are causing this. It still killed people.

This is true for most of the early medicine/illneses/hygiene, this was just an example I remember. Especially in regards to germs and bacteries, the humanity wasn't even close to getting it right.

No, things outside the player's field of view are unloaded to save memory, obviously.

Obviously, yes. But now the question is, can you be aware of things that don't exist?

Animals are sometimes declared 'extinct' (no one is aware of any living examples) while they still exist (sometimes for decades).

Until 1967, noone was aware of the existence of gamma-ray bursts, the result of the biggest explosions in the universe. The bursts were only visible to specialized satellites.

Right now, people are suffering from diseases caused by unknown viruses.

Well I exist, despite it seeming that no one else in the world is aware of my existence.

Object permanence is technically an axiom. The idea that things exist even when we aren't observing them.

There's also a problem with terms, particularly related to quantum mechanics. It uses the term observer. To a layman, that's a person watching. To a scientist its any collection of atoms/fundamental particles that can cause the quantum waveform to collapse.

The results of the axiom are that things do exist when we are not observing them. Our observations don't back propagate to retroactively bring them into existence. We can't prove that however, though it's fundamental to a lot of science making sense (quantum mechanics being the oddball).

Bacteria and viruses existed for billions of years before humans ever existed and the majority of the time since. Dinosaurs existed before we were aware of them. Lots of things have.

This isn't a very well thought out Shower Thought

Yes, my one man black metal project exists and no one knows about it. 🥺

Yes, they necessarily do.

Write your definition for "things" and that'll answer your question for you.

That's solipsism

Yes. Because people are not the only observers.

What qualify as observers though? Or, how far divorced from an event counts as unobserved?

If a tree falls in a forest and scares a rabbit which a dog barks at which I hear... is that chain of observation enough to grant existence to the tree?

Technically they exist.
But do they exist for you if you don't even think of them? Theological/ philosophycal views might say no.
Tho you can still be affected by unkown therefore "non-existent" things.
Nowadays I call "tap to pay" magic. I know the very basic things to go in there - but I couldn't recreate it. Thos is kinda the same tone as your question.

Have a read through this:

https://en.wikipedia.org/...

Your question is a lot like this thought experiment:

If a tree falls in a forest and no one is around to hear it, does it make a sound?

Whatever your answer is to the above text can be applied to your question.

The atoms are there for sure, but we could argue, whether it is a thing/object without an animal being aware of it, since it's us that define things to be objects.

The universe doesn't care whether a pile of atoms behind Pluto happens to be chair-shaped. It's only when we look at it, that we declare it an object.

Of course. I think there are many things that we haven't detected because we lack the instruments or even the concept they exist

Humans are constantly discovering life on Earth in places it was thought impossible, like deep underground or in very hot water around volcanic vents.

Certain cancers (HPV, EBV, HBV) have been discovered to be caused by viruses, not just randomly out of control cell replication.

IMO even astronomers suffer from short-sightedness. They tend to classify things in terms of our own little solar system when actually with billions of stars and trillions of planets there are likely very many astronomical objects and phenomenon that we have never observed or thought of.

This isn't really an answer to your question, but I think it's more in the spirit of it than some of the actual answers you're getting;

Does something exist just because you observed it?

The duality behind being both aware of something that can exist without your knowledge while also not being aware of its existence. Depending on if it's conception has been conceived first. Then it would exist without any knowledge and would count. But if you know it can exist than its already a possibility.

At one point no one knew how gravity worked and yet the earth still orbited the sun

Yep. There are many billions of people around the world who don't know you exist yet you do. Although how sure are you that you exist?

Things can and do.

So, can something exist that is in no way quantium entangled with anything that comprises your experience of existence?

If you subscribe to the multiworld principle, basically anything potentially viable can and will.

Can something exist if you are not aware of it?

Most of reality. Human experience is quite limited.

Depends on your position on philosophical realism.