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Our eyesight is a lot better than a lot of other animals at least. Other than damn birds

I think they do. If you're looking for literature, I have no scientific references, only the testimony of a dog breeder, myself. I have a dog, Dima, who had had four litters of puppies. We kept one of the puppies from the original litters, named Drea. All the puppies from the following litters recognized Drea as having higher status. Dima's last litter all got adopted by one owner, my cousin, meaning they all went to the same household. After some time passed, we took Drea to my cousin's to see how the dogs would interact. At first, they treated her like any other normal dog, excited and curious to know more about their visitor, but after recognizing her scent, they reverted to the dominance hierarchy that they established when they were puppies, recognizing Drea's higher status. Some time later, we took their mother, Dima, to my cousin's house. Upon entering the yard, all the puppies from that litter instantly recognized their mother, all three of them peed on themselves and furiously wagged their tails. She recognized her puppies as she held her head up high and instantly disciplined them when they became overly enthusiastic about seeing her. It was as if she was reminding them about recognizing and remembering boundaries. After she calmed them down, she began meticulously grooming them and after a short while, all three puppies (now fully grown dogs) all took a nap with their momma. It was something else to behold...

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Consider Newtonian gravity. If an object falls directly into the gravitating body with no sideways motion, it will simply collide. It's orbital angular momentum that causes the object to be ejected back outward.

How does this work? If you write down the equation of motion for the orbital distance r, two forces emerge. One is the gravitational attraction, which scales as 1/r^(2). The other is a centrifugal repulsion term, which scales as L^(2)/r^(3), where L is the angular momentum. As the distance r becomes small, the centrifugal repulsion eventually dominates, ejecting the object back out to apocenter, as you say.

This works because the attractive force scales as 1/r^(2) at distance r. If the attractive force scaled as 1/r^(3) or steeper, then the centrifugal repulsion would be no longer guaranteed to overpower the gravitational attraction at sufficiently small radii, so there would be nothing to prevent the orbiting object from eventually colliding with the central gravitating body.

While gravity in general relativity can't be exactly described by a radial force law, the same basic idea applies. See for example how a number of 1/r^(3), 1/r^(4), etc. terms arise in the post-Newtonian expansion (scroll to equation 203).

That's true for nonrotating black holes, anyway. In the idealized rotating black hole solution, it is actually possible for the centrifugal repulsion to overpower the gravitational attraction! This is what leads to the crazy conformal diagram for a rotating black hole that suggests you can fall in and emerge back out in a different universe. However, there are many good reasons to expect that this idea does not work for realistic black holes and is just an artifact of the idealized construction.

Indeed, the inertial-ness of a reference frame is only a local property (local here meaning infinitesimal displacements).

What you said about dark energy acting as a repulsive source, I am now confused how so.e scientist recently came to the conlusion that black could be sources of dark energy. Especially because afaik black holes are incredibly dense objects made form "normal" matter that collapsed due to their gravity. Here dark energy being a repulsive force doesnt make sense to me if all we can observe is the incredibly powerful gravitational waves of black holes.

It sounds like you're imagining "expansion" to be some outward expansion from a point in space, rather than spacetime expanding everywhere. There's no reason to tie the age of the universe to its size (other than just how its size changes proportionally, relative to itself with time). It could have been any size prior to inflation. The fact that the observable universe is larger in lightyears than the age of the universe in years is not surprising or particularly meaningful.

Doesn't matter about their current velocities. The universe is 14B years old. It's bigger than 28B light years wide. Therefore the universe had to expand faster than the speed of light.

Further, light goes through the universe. The universe expands outside of itself into who knows what. We have no idea if the speed of light applies outside of the universe. Same for thermodynamics.

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thank you very much

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This might help:

https://physics.stackexchange.com/questions/72174/why-do-moving-particles-emit-thermal-radiation

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Here’s a really good article that goes into the whole process and its real world consequences.

https://apps.seattletimes.com/reports/sea-change/2013/sep/11/oysters-hit-hard/

Maybe related - someone did a test some years back - took a handful of people into a room and let a dog in. Everyone ignored the dog except for one person, who petted it up and paid positive, emotional attention to it.

The a few years later, they took the same dog to a room of people and the "nice guy" was one of them. In every case, the dog "remembered" the "nice guy" and acted familiar with him.

Wish I could cite the actual test, simply can't remember where I read it (Maybe a Desmond Morris book? The guy who writes the animal behavior books), but it seems to play along with dogs having a "world" of scent information that's unimaginable to us. I guess if they have decent memories, there's a survival advantage in remembering a friendly scent.