At its core,

[MadMojoMonkey]

If the machine running the simulation uses discrete mathematics, there will be unavoidable artifacts as waves propagate through the discrete lattice.
These artifacts are not observed. I.e. there are not preferential directions in the universe. Waves propagate in the same way in all directions. E.g. there is no direction-based attenuation, which is an unavoidable artifact of a body made of discrete "lobes" - like atoms in a crystal.

Just to preempt any mention of the Planck Length: that number is a trick of mathematics and has nothing to do with physics, as such.

Summary: if the universe is a simulation, the graphics are fucking crisp!


Interestingly, by information theory, if the universe is a simulation, then the device running said simulation has at bare minimum as many particles as the universe it simulates.

If you're going to build anything in this universe which simulates another universe, that simulated universe will likely be many orders of magnitude smaller in scale than the universe in which you exist.

Summary: simulations are smaller and smaller as you nest more simulators inside simulations.

***
Does the "feeling" being preceded by other chemical processes in a brain mean that the feeling is wrong?
I'm not sitting here questioning if I should have chosen different weather for today. My brain is not simply asserting the feeling that I've made a choice over arbitrary things in my life.
Does it fit the observed data to posit that a brain makes a decision, and only after said decision is made takes the luxury of "feeling" like it made a decision?

[Poopadoop]

Does the "feeling" being preceded by other chemical processes in a brain mean that the feeling is wrong?

If those brain states precede and predict the feeling of making a decision, then I would hazard to say 'yes the feeling is wrong'; your feeling of having made a decision is a phenomenological artefact of the activity in your brain, nothing more.

We constantly make decisions without any sort of rumination. Are these decisions 'free' in the sense that we could have done something else? It seems hard to agree with that idea. And I'm not speaking solely about reflexive or automatic actions - just think of the next conversation you have with a friend - how much of what either of you say do you actually think about before you say it? Not much if you're like me and my friends, you both just blather on.

Surely you've done things where you've had no idea wtf fuck compelled you to do them.

I'm not sitting here questioning if I should have chosen different weather for today. My brain is not simply asserting the feeling that I've made a choice over arbitrary things in my life.

That just shows you understand what is possible and what isn't. Other people do sit around thinking they can affect all sorts of things they can't affect. But what you think you're in control of and whether you have the free will to decide to change it seem orthogonal to me at least.

Does it fit the observed data to posit that a brain makes a decision, and only after said decision is made takes the luxury of "feeling" like it made a decision?

In a sense, yes, but I think you're ascribing too much sophistication to what the brain is doing - it's basically just a bunch of 1s and 0s that are programmed to follow certain patterns - e.g., respond in such a way so that the person turns their eyes and head towards a loud noise, for example.

The real mystery is why we have consciousness at all, since our brain could arguably pull all the right levers without us ever having any sort of phenomenological experience of even existing, never mind feeling, thinking, seeing, being happy or being sad, etc..

[Poopadoop]

Here's another way of looking at it - if you take out a person's visual cortex, their experience of vision is basically that they are blind. If you take out a person's dlpfc (part of the frontal lobes), their experience of decision-making is analogous - they are 'blind' when it comes to making up their mind.

e.g., This poor bastard can't even decide what he can't decide about. He can talk about things he is going to do in the future but chances are he won't do any of them.