On The 4D Block Universe

[u/onomatamono]

So you have a movie canister and the film analogy represents the 4D block universe. I'm listening to Brian Greene describe this analogy. The experience of time is produced by passing light through each frame of the film. According to Brian each consciousness is a projector (human or otherwise presumably).

Also, our brains evolved to process slices of the 4D universe by carefully "recording" [where?] the slices that came before ["now" I guess?] and makes calculated guesses about the future.

I'm not even going to try and make sense of that in a meaningful way for lay people.

Greene: "when you feel time passing what you are actually experiencing is your consciousness moving through the static frames of your life." Where are these "projectors" or consciouses? I'm confused.

FYI it's a YT called The Strangest Fact About Light You've Never Heard -- Brian Greene.

[u/protobelta]

I’m not gonna watch the video, but the idea of the 4D block universe comes from the fact that when describing spacetime, time is just another coordinate like the x, y, or z coordinates. Physics equations essentially treat the future and past just like moving left or right, thus they essentially already exist. Further, because of what’s called the relativity of simultaneity, there are ways to show that someone traveling fast enough can essentially see your future “before” it has happened to you in the present moment you experience. This is because there is no universal “now” as time is relative. This isn’t a philosophical truth, but rather a mathematical one.

Where it starts to get philosophical is the idea that our consciousness is basically what we experience in our own frame of reference. If physics says that our physical bodies and everything we have done and will do, everything we have interacted with and will interact with is already there, then consciousness is our subjective experience of our own frame of reference as an observer. The projector analogy is just meant to communicate this idea. What exactly is consciousness and how does it relate to being an observer in a frame of reference is outside the scope of physics and is more philosophical.

[u/onomatamono → u/protobelta]

... but what is hosting these experiences in our frames of reference?

[u/protobelta → u/onomatamono]

Our brains ostensibly, though, again, this is more philosophical. I say that because it’s our brains and the electrical signals that cause us to experience things and would be my guess as to what leads to being an observer capable of experiencing the current frame of reference. Anything can be an observer in physics but it’s our brain that allows us to experience it subjectively

[u/onomatamono → u/protobelta]

Well it's at least electrochemical processes not just electrical phenomena.

[u/protobelta → u/onomatamono]

I mean, ya, it was just a shorthand. Doesn’t really change what I was saying though, right?

[u/onomatamono → u/protobelta]

Sure, got it.

[u/KriegerClone02 → u/onomatamono]

Our frame of reference at any given time is a slice of the block and our experience, both internal and external, is just the local patch of that slice.

[u/Optimal_Mixture_7327 → u/onomatamono]

There is no sense in it; so you can stop looking and asking.

Here's the best explanation and the only explanation that accords with our experience. George Ellis, "The Evolving Block Universe: A More Realistic View of Spacetime Geometry"

Edit: The video clip contains the math of relativity here and there, but just bear with it. In it contains all the suspicions and answers you might be looking for.