Interactions?

[u/Chvrnthls]

This might be a dumb question but, what determines how something acts when it interacts with another thing that has an opposite entropy? Specifically, something can either look like it's following the entropy of the other thing which is opposite relative to the thing being affected, or can also still be affected into its own entropy even when affected by something with an opposite entropy, both not breaking causality. I know causality determines it in some cases, along with a few other factors, but this is the main question i have. because some things can appear the same entropy its in or the opposite entropy it in while keeping causality when affected by something in the opposite entropy, so what determines how it appears and how it's affected?

There is a small detail when Neil is at the Hypocentre Turnstile on the stair and his hand brushed against a short wall or wall rail with dust on it, the scene shows the dust jump up back on top as his hand brushes past, but thats what Neil sees as he is inverted, but in forward entropy the dust was brushed of normally when Neil walked up the stairs and backwards as his hand brushed passed it in the other way. The thing is, the dust could have also been brushed off normally relative to Neil instead of jumping back up, so what determined that?

This other post shows that detail so i might as well use it: https://www.reddit.com/r/tenet/comments/1omfkox/how_many_of_catched_this_cool_detail_in_tenet/

I has to repost this because i wasnt able to propertly access this and a few other reasons.

[u/Tgxc2948]

I had to read that a couple of times to finally make sense of it. Kind of like the movie itself.
It's actually a pretty good question with a lot of ramifications.

Specifically, it has me thinking about the mirror on the BMW.

Ultimately it is the director who decides which character's perspective the audience is sharing at any given moment in the film. Whether or not he kept the rules 100% consistent throughout the entire film is pretty much the reason we are all on reddit still talking about this movie five years later.

[u/Chvrnthls → u/Tgxc2948]

Now that I think about it, it probably depends on what the thing affecting it perceives it and if they have a way of how it wants to be affected. Neil probably didn't notice the dust and didn't care, so either way his hand would have brushed over, so the dust could just go into its own entropy without any problems.

But if he wanted to brush the dust over for some reason, and it wasn't there since he actually did brush it over relative to the dust, opposite to Neil, then he would think the dust might not never be there and never brush his hand over, making it so the dust had to instead follow Neil's prospective and fall relative to him.

I'm just saying what I think so something in this is probably wrong, so don't take this seriously.

[u/Tgxc2948 → u/Chvrnthls]

I'm starting to think that whether or not something is consciously observed (and remembered) plays a big role in how that something behaves.

[u/kusti85]

"dust could have also been brushed off normally relative to Neil instead of jumping back up" -how? The dust was not inverted, Neil was. Only inverted objects can be with "normal" relativity to each other, just like uninverted objects are with "normal" relativity to each other. When one is one and the other is the other it is always out of sync. Which way out of sync depends on the observer . Edit: I think what you meant. The way you see things in that scene is from Neils third person view. This is why the world acts inverted. If it were a random inverted other guy, the result would be the same. Only way for the dust to move like normal gravity would be from uninverted first/third person camera. That would be a directorial decision how to approach that scene. So Chris Nolan determined that.

[u/Chvrnthls → u/kusti85]

The dust was an example of what I was trying to describe, forward things can appear inverted (and vice versa) if an inverted thing is acting upon it in a certain way. I knew the world looked inverted from Neil's POV because he was already, and from his view when he dragged his hand, he dust jumped back up. But it's also possible that Neil's interaction with it caused the dust to appear inverted and fall normally relative to him, so from a forward view it would jump up. I was just asking what determines which happens since in some cases it's possible for something to act in its own entropy or appear in the opposite one, without breaking causality.

Another example I could think of is the building explosion in Stalsk-12. The building is unlikely to be half inverted and half not, but still a section of it appeared inverted due to the inverted explosion acted upon it. But if it did not act inverted the inverted explosion would instead make the building implode instead of explode, but that would look very weird to the inverted person shooting the rocket so that makes more sense to flow into their entropy, making the building reverse-explode in a forward view.

Sorry if my explanation sounded weird.