How to understand the universe when you're stuck inside it

#1
https://www.quantamagazine.org/were-stuc...-20190627/

EXCERPT: The universe is kind of an impossible object. It has an inside but no outside; it’s a one-sided coin. This Möbius architecture presents a unique challenge for cosmologists [...] It’s a situation that Lee Smolin has been thinking about for most of his career.

Smolin often finds himself inspired by conversations with biologists, economists, sculptors, playwrights, musicians and political theorists. But he finds his biggest inspiration, perhaps, in philosophy — particularly in the work of the German philosopher Gottfried Leibniz [...and his...] fundamental ingredient ... the “monad,” a kind of atom of reality, with each monad representing a unique view of the whole universe. It’s a concept that informs Smolin’s latest work as he attempts to build reality out of viewpoints, each one a partial perspective on a dynamically evolving universe. A universe as seen from the inside.

Quanta Magazine spoke with Smolin about his approach to cosmology and quantum mechanics, which he details in his recent book, Einstein’s Unfinished Revolution. The interview has been condensed and edited for clarity.

[...] You have a slogan: “The first principle of cosmology must be: There is nothing outside the universe.”

[...] The statement that there’s nothing outside the universe — there’s no observer outside the universe — implies that we need a formulation of physics without background structure. All the theories of physics we have, in one way or another, apply only to subsystems of the universe. They don’t apply to the universe as a whole, because they require this background structure.

If we want to make a cosmological theory, to understand nature on the cosmological scale, we have to avoid what the philosopher Roberto Unger and I called “the cosmological fallacy,” the mistaken belief that we can take theories that apply to subsystems and scale them up to the universe as a whole. We need a formulation of dynamics that doesn’t refer to an observer or measuring instrument or anything outside the system. That means we need a different kind of theory.
You’ve recently proposed such a theory — one in which, as you put it, “the history of the universe is constituted of different views of itself.” What does that mean?

It’s a theory about processes, about the sequences and causal relations among things that happen, not the inherent properties of things that are. The fundamental ingredient is what we call an “event.” Events are things that happen at a single place and time; at each event there’s some momentum, energy, charge or other various physical quantity that’s measurable. The event has relations with the rest of the universe, and that set of relations constitutes its “view” of the universe. Rather than describing an isolated system in terms of things that are measured from the outside, we’re taking the universe as constituted of relations among events. The idea is to try to reformulate physics in terms of these views from the inside, what it looks like from inside the universe.

How do you do that?

There are many views, and each one has only partial information about the rest of the universe. We propose as a principle of dynamics that each view should be unique. That idea comes from Leibniz’s principle of the identity of indiscernibles. Two events whose views are exactly mappable onto each other are the same event, by definition. So each view is unique, and you can measure how distinct one is from another by defining a quantity called the “variety.” If you think of a node on a graph, you can go one step out, two steps out, three steps out. Each step gives you a neighborhood — the one-step neighborhood, the two-step neighborhood, the three-step neighborhood. So for any two events you can ask: How many steps do you have to go out until their views diverge? In what neighborhood are they different? The fewer steps you have to go, the more distinguishable the views are from one another. The idea in this theory is that the laws of physics — the dynamics of the system — work to maximize variety. That principle — that nature wants to maximize variety — actually leads, within the framework I’ve been describing, to the Schrödinger equation, and hence to a recovery, in an appropriate limit, of quantum mechanics.

[...] It reminds me of a lot of work that’s going on now in physics that’s finding surprising connections between entanglement and the geometry of space-time.

I think a lot of that work is really interesting. The hypothesis that’s motivating it is that entanglement is fundamental in quantum mechanics, and the geometry of space or space-time emerges from structures of entanglement. It’s a very positive development.

You’ve said that these ideas were inspired by Leibniz’s Monadology. Did you just happen to pull out your Monadology and reread it?

I first read Leibniz at the instigation of Julian Barbour, when I was just out of graduate school. First I read the correspondence between Leibniz and Samuel Clarke, who was a follower of Newton, in which Leibniz criticized Newton’s notion of absolute space and absolute time and argued that observables in physics should be relational. They should describe the relations of one system with another, resulting from their interaction. Later I read the Monadology. I read it as a sketch for how to make a background-independent theory of physics. I do look at my copy from time to time. There is a beautiful quote in there, where Leibniz says, “Just as the same city viewed from different directions appears entirely different … there are, as it were, just as many different universes, which are, nevertheless, only perspectives on a single one, corresponding to the different points of view of each monad.” That, to me, evokes why these ideas are very suitable, not just in physics but for a whole range of things from social policy and postmodernism to art to what it feels like to be an individual in a diverse society. But that’s another discussion! (MORE - details)
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#2
Casually spoken from the armchair.....

Like reading about the thoughts of others even if I don’t quite understand them or if they’re completely contrary to my way of thinking. In my case it’s more of the former. Tells me people are observing. Important, no matter how brilliant an idea is, to hear it. Some people invest a lot of time and energy formulating their ideas, some are more casual and some border on the obsessive. Important thing is to get it out there and have it examined.

So as I was reading the OP my inquisitive mind wondered how Smolin would describe an event for a photon or anything that experiences no time and how do you pinpoint a spatial coordinate in an expanding universe. But I figure those questions probably fall into the observation from outside universe category?

The other thing I wondered about was whether the present is an event? All events for the observer occur in the past except the present. Only thing I could conclude was that the present isn’t an event and if it is an event then does its time coordinate encompass the entire universe?
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#3
(Jul 2, 2019 01:20 PM)Zinjanthropos Wrote: . . . So as I was reading the OP my inquisitive mind wondered how Smolin would describe an event for a photon or anything that experiences no time and how do you pinpoint a spatial coordinate in an expanding universe. But I figure those questions probably fall into the observation from outside universe category?


From a source at least outside the photon, anyway. We're forcing our explanatory and "descriptive need" for spatiotemporal coordinates onto objects and circumstances which lack any content concerning "what's going on" or "what is". In terms of the accepted convention that the cosmos abroad is mindless, photons do not experience anything -- period. They do not carry either a static or a mutable, shown representation of their own being, much less the state of the world. So what a photon is feeling one way or another about time (in this case no change) is always an imaginary perspective we impose on it.[*]

Quote:The other thing I wondered about was whether the present is an event? All events for the observer occur in the past except the present. Only thing I could conclude was that the present isn’t an event and if it is an event then does its time coordinate encompass the entire universe?

Yes, the latter. As far as HIS believing in a literal global "now" with all events/things being embraced by it... Smolin and philosopher of physics Tim Maudlin are objective realists about the passage of time. Wherein it's not just another illusion or quale of consciousness like the experience of colors, odors, etc. (In contrast to the technical meanings of those outside the brain as specific EM frequencies, different molecules wafting in the air, etc). But it is not the common presentism option they advocate but rather the GBU view, which physicist Sean Carroll illustrates via a simple diagram in this blog entry (labeling it "possibilism" there).

So in essence, they apparently believe that everything in the cosmos is participating in a simultaneous or coordinated global "now". That the next or future moments are being substantively created by an asymmetrical process (from nothing?) and added to the block-universe or whatever mathematical model of spacetime. That we exist in the past but are philosophical zombies there due to "this now" requiring even more "special" status so as to not fall back into what the eternalism option holds about the past. (Another way to put that is how would we know that we're really in the true "present" if our body states in the past were also experiencing their applicable time periods?)

To accommodate all changes occurring at the subatomic level, that would mean such a universal "now" is at least less than a yoctosecond in duration (W & Z bosons need their ephemeral existence period). In contrast to our elephant-sized microsecond experiences of what "now" is. So ironically one's personal version of "now" would still be specious or bogus, anyway.

Remember that this is all in an objective realist context -- we can't be objectifying our own subjective "moments" as what the measurement of a "now" is for the whole freaking universe, especially at the micro-level. Plus, even our subjective moments are erratic in duration from person to person and within ourselves -- they don't agree with each other in terms of a consistent time unit. Which is to say, that would hardly be something to base a global standard on to begin with.

- - - footnote - - -

[*] Interesting that even in everyday language we have a tendency to regard time as an "experience" and dependent upon the cognition that a state has changed or is different from the previous. I've yet to figure out what is relevant about a mind-independent passage of time (literal change as opposed to a continuation of differences) when such a non-aware or non-representational condition can't even validate its own happening or objective reality. But OTOH, all sorts of silly things can become significant within a game or model itself which experts are playing for practical or recreational purposes.
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#4
What ya think CC, how does Smolin et al know we’re stuck inside a universe? Pretty big assumption I would think. Maybe they should start there first, could it be we are the outside looking in?

Just thinking CC....What if we are in a muddle of several transparent universes and they are all expanding? Do we actually know what we observe is contained within one universe?
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#5
(Jul 3, 2019 01:15 AM)Zinjanthropos Wrote: What ya think CC, how does Smolin et al know we’re stuck inside a universe? Pretty big assumption I would think. Maybe they should start there first, could it be we are the outside looking in?

Barring our being in the liquid-filled pods of The Matrix or being trapped in VR suits and goggles, we don't have any potential observers stationed outside the cosmos.

As the interviewer says, “There is nothing outside the universe" is a slogan. Science has a lot of pin-up dogmas and operating presumptions like that which working or practicing physicists may not pay much any attention to, or need to. Smolin actually emphasized it 18 years or more ago: https://www.nytimes.com/2001/08/19/books...avity.html

It's a logical tautology that is necessarily true simply because of what the word "universe" is preset to mean: By definition the universe is all there is, and there can be nothing outside it. And, by definition, neither can there have been anything before the universe that caused it, for if anything existed it must have been part of the universe. So the first principle of cosmology must be `There is nothing outside the universe'.

It's play on the idea of the universe being a closed system, which in turn originally goes back to philosophical naturalism, which was in the context of supernaturalism rather than thermodynamics, an absolute background, etc: As defined by philosopher Paul Draper, naturalism is "the hypothesis that the natural world is a closed system" in the sense that "nothing that is not a part of the natural world affects it." More simply, it is the denial of the existence of supernatural causes. In rejecting the reality of supernatural events, forces, or entities, naturalism is the antithesis of supernaturalism. (Naturalism)

In that 2001 piece above, as well as this interview, Smolin is roundaboutly using it to poke at some things, first being Newton's already dethroned conception of space and time:

SMOLIN: It means that the explanation for anything in the universe can involve only other things that also exist in the universe. This has very important consequences, each of which will be reflected many times in the pages that follow. One of the most important is that the definition or description of any entity inside the universe can refer only to other things in the universe. If something has a position, that position can be defined only with respect to the other things in the universe. If it has a motion, that motion can be discerned only by looking for changes in its position with respect to other things in the universe.

So, there is no meaning to space that is independent of the relationships among real things in the world. Space is not a stage, which might be either empty or full, onto which things come and go. Space is nothing apart from the things that exist; it is only an aspect of the relationships that hold between things. Space, then, is something like a sentence. It is absurd to talk of a sentence with no words in it. Each sentence has a grammatical structure that is defined by relationships that hold between the words in it, relationships like subject-object or adjective-noun. If we take out all the words we are not left with an empty sentence, we are left with nothing. Moreover, there are many different grammatical structures, catering for different arrangements of words and the various relationships between them. There is no such thing as an absolute sentence structure that holds for all sentences independent of their particular words and meanings.

The geometry of a universe is very like the grammatical structure of a sentence. Just as a sentence has no structure and no existence apart from the relationships between the words, space has no existence apart from the relationships that hold between the things in the universe. If you change a sentence by taking some words out, or changing their order, its grammatical structure changes. Similarly, the geometry of space changes when the things in the universe change their relationships to one another.

[...] The view of space as something that exists independent of any relationships is called the absolute view. It was Newton's view, but it has been definitively repudiated by the experiments that have verified Einstein's theory of general relativity. This has radical implications...
Quote:Just thinking CC....What if we are in a muddle of several transparent universes and they are all expanding? Do we actually know what we observe is contained within one universe?

Most of the universe isn't observable and never will be. Of course, throw in those who favor the various kinds of multiverse theories -- which, if happening to be case... Then you can see how the a preset lexicon for an enterprise along with its similarly preset guidelines might almost become obstructive biases in some areas in the future. Despite great success with those established preferences in most of its other and past pursuits.
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