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Do you know the concept of space-time, block universe, B-theory of time, etc? How physics assumes that the laws of physics don't know the notion of "now"? And how physicists usually start every calculation with "let X denote the set of events", all the past and future events?

Isn't that depressing? The future is true, even if we can't know it. (Even in a finite, discrete and deterministic universe, which we can compute on computers, habitants of the universe can't know the future. A software can't compute its future. A similar reasoning to the halting problem can show this.)

May I interest you in an other view? Slice Universe to the rescue! There is only now, and the now is true. There is matter, in a particular, ever changing spatial configuration. In 3d. The now is true, also it changes. Only the real people, made out of matter can experience things, simulated people, or the people that are not even simulated don't have real experiences. The past is not true, but we have some information about it, what the past can possibly be. So is the future, it is not true, but we have some information about it. There is no ontological or qualitative difference between the past and the future, only quantitative (which comes from the ridiculous amount of negentropy at the beginning of our universe).




> Isn't that depressing?

No? Why would it be?


We live in a set of time slices that we are able to control through the choices that we make as we slide through the deck. The past is done and locked up, carved in stone and can be recalled with high fidelity if we choose to dwell there. The future is always in your face - another decision to make, lives to influence, bullets to dodge - all presented as you color the current time slice with the events your choices allow. Choices are filters on possible paths for your future, some can be looped many times while others permanently exclude specific outcomes. As we color the time slice we can know parts of the future by understanding consequences of the choices we are making though we can't know it will all fit far into the future. The past is left as an exercise in recollection to serve up reminders of all the unpleasant loops we threw in our life path and most importantly, to help us choose a better, more productive path when we find ourselves at a similar node in the future.


How could that possibly support the relativity of simultaneity? Different reference frames disagree on what is happening "now."


I mean, relativity already means everything depends on location, so this should just fit right in, right? The contents of your “slice” are from right now at your location, from 20 years ago at locations 20ly from you, 30 years ago at 30ly, etc. We literally can’t know what’s happening at any time other than 20 years ago at locations 20ly from us, after all. So I’d say this jives well with the various “curves” relativity implies exist in spacetime. (Note: I am not a physicist so I’m happy to learn why/if I’m wrong here!)


How do you think this conceptual model fits at the subatomic scale; everything being a warping of fields? At first glance I can't tell if it works because there is no such thing as a slice at the quantum level. Well, depending on which theoretical model you're looking at. I suppose either way it's might be considered true if mathematically we're talking about the properties of a particle. But even then no one alive today can say for certain why those properties exist, conclusively I mean, outside of theory. We barely have a grasp on the manor in which they exist, which is the theory. For example, based on what we know about the proposed axion particle, how does this slicing concept affect the nature of it warping spacetime? Bringing something new to the table there would be quite the accomplishment here!

edit: typo


The people in other reference frames must just be simulations, so their experiences are invalid.


Lol.

Nah, if we allow virtual experiences, than any model naturally becomes the block universe.

I believe, that question of experience is still unsolved. Why do we seem to live in a world made of matter and governed by physics? Is it the same for people that are simulated in a computer? Is it the same for people that are not simulated by a computer (because it is plugged out)? How do they perceive if the data is mangled? Etc. BTW the block universe also needs to solve this problem. But in order to not to be in a block universe, we need the answer that being material based is different than being simulated on a material based simulator, or not even being simulated, just the possibility of it.

@sobellian: relativity doesn't need the block universe. It works perfectly fine if people just get shorter when they speed up. Then the simultaneity of events in a frame is not the same as being in a slice.


Maybe I misunderstand, but could an alternate theory be that reality and the universe are not the same thing?


This is interesting! What do you make of retrocausal effects in "image exposure" experiments, and other psi related phenomena. I'm curious if you have ideas for a physical theory that speaks to precognition and remove viewing?


What are these image exposure experiments?


I'm no scholar, so I may be missing crucial papers, but here are some:

- https://www.apa.org/pubs/journals/features/psp-a0021524.pdf (original experiments)

- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4706048/ (replications review)

- https://citeseerx.ist.psu.edu/document?repid=rep1&type=pdf&d... (review of related evidence)

Here's something more far out I just found trying to connect physical theories to some of this: https://old.hessdalen.org/sse/program/Antonella.pdf

Some related light discussion of similar issues and intersection of physics and consciousness: https://quantumphysics-consciousness.eu/index.php/en/2022/06...

And a few other ones:

- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4141237/ (review of many experiments)

- https://arxiv.org/pdf/1111.6584.pdf (discussion of possibly physics)


What to read on the slice universe?


It sounds similar to (but possibly different from since I never heard the term "slice universe") the theory of presentism in the philosophy of time.

That's the view that all that exists is the present. What we call the past is what used to be present and what we call the future is what one day will be present, but neither the past or future exist so long as they are not the present.

https://plato.stanford.edu/entries/presentism/



There is no fixed way to slice up the universe into 3d slices.




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