Block Universe

[pood]

The growing block theory is incoherent.

It holds that the present and past exist, but not the future, which is always coming into existence.

In addition to contradicting relativity theory as much as presentism does, it is internally inconsistent. If 1920 exists, it means all the years up to the present exist from the point of view of 1920. So for 1920 (and all prior years) the future exists after all!

 

[Jarhyn]

The growing block theory is incoherent.

It holds that the present and past exist, but not the future, which is always coming into existence.

In addition to contradicting relativity theory as much as presentism does, it is internally inconsistent. If 1920 exists, it means all the years up to the present exist from the point of view of 1920. So for 1920 (and all prior years) the future exists after all!

It's like saying "it's a function before the dot and a relation after the dot, despite the fact that every point on the line is continuously "dot""

If the point nearer to the end is a dot than this point when we are there observing it, and the interstitial portion is "functional" not "relational", and if there is always a point n+1 that will be encountered where the point n to n+1 resolves as functional, then the whole line MUST be functional, not relational.

 

[pood]

Metaphysics is attempt to describe reality without math and physics.

To reiterate: Minknowski block wold is mathematical, not metaphysical. But at the same time it is a metaphysical stance based on math.

However, this brings up the issue of whether maths are isomorphic with reality. Max Tegmark says they are. Others disagree. Back to philosophy!

 

[pood]

As I understand it Einstein initially rejected Minkowski block world not because he considered it metaphysical — Einstein was a metaphysician as well as a scientist — but precisely because he considered it a mathematical abstraction not connected to reality. Later he seems to have concluded it was correct. But it should be recalled that Einstein was a student of Minknowski, who called Einstein a “lazy dog.” So maybe Einstein’s initial rejection of Minkowski was based on personal animus. Thus we see that not just philosophy, but personal opinions and conflict, can affect science.

 

[pood]

Steve could simply Google “the mathematics of Minkowski spacetime” or some such.

 

[pood]

I mean, after all, Minkowski was a … mathematician.

 

[Michael S. Pearl]

The growing block theory is incoherent.

It holds that the present and past exist, but not the future, which is always coming into existence.

In addition to contradicting relativity theory as much as presentism does, it is internally inconsistent. If 1920 exists, it means all the years up to the present exist from the point of view of 1920. So for 1920 (and all prior years) the future exists after all!

Doesn't that all just indicate a problem with the insistent use of exist and existence? This can be tied in with the never-ending determinism ruminations by instead saying that the terms past and present always refer to determined, set, fixed states/situations so that (let's just call it) the details of "the present and past are set, but the details of the future are not".

Is there a problem with thinking of block spacetime as mapping (or locating) occurrences in terms of the relative wheres and whens independent of the whats which obtain?

 

[pood]

The growing block theory is incoherent.

It holds that the present and past exist, but not the future, which is always coming into existence.

In addition to contradicting relativity theory as much as presentism does, it is internally inconsistent. If 1920 exists, it means all the years up to the present exist from the point of view of 1920. So for 1920 (and all prior years) the future exists after all!

Doesn't that all just indicate a problem with the insistent use of exist and existence? This can be tied in with the never-ending determinism ruminations by instead saying that the terms past and present always refer to determined, set, fixed states/situations so that (let's just call it) the details of "the present and past are set, but the details of the future are not".

Is there a problem with thinking of block spacetime as mapping (or locating) occurrences in terms of the relative wheres and whens independent of the whats which obtain?

On the block world hypothesis, the past and present are set and fixed from the human perspective. But the block world states that the details of the future are also set and fixed, but we just don’t know what they are.

Of course, we don’t know very much about the details of the present or past, either.

Max Tegmark likens the situation to the frog’s view and the bird’s view of reality. On the frog’s view, the future is unfolding. On the bird’s view, past, present and future are all right there.

 

[bilby]

Doesn't that all just indicate a problem with the insistent use of exist and existence? This can be tied in with the never-ending determinism ruminations by instead saying that the terms past and present always refer to determined, set, fixed states/situations so that (let's just call it) the details of "the present and past are set, but the details of the future are not".

The problem is that, according to General Relativity, time is not absolute. Different observers can disagree on whether a given event lies in the past, or in the future, (or for that matter in which order two events in the past occurred) so it follows that either both past and future are fixed, or both past and future are mutable.

It is rare to find anyone who asserts that the past is mutable; So the conclusion is that the future must be fixed.

If we are going to assert that the future is not yet set, then we need to define whose future we are discussing, because according to GR, my near future could be your recent past.

 

[steve_bank]

Steve could simply Google “the mathematics of Minkowski spacetime” or some such.

Where would you be without me to prod you? It is hard work.

Way back I thumbed through a book by Minkowsky. Paraphrasing, when a theory blows up it does not mean reality blows up it means you have reached the limits of your understanding. It stuck with me.

For example the hot dense soup of the BB represents the limit of or ability to understand reality

The philosophical debate of free will vs determinism and time represents our limits of underthing.

If the issues could be settled scientifically by experiment the debate would end, and you would lose something to talk about.

To me te idea that all events past,present and future exist sitaneously brings in quetions ofcausality and energy.

I uswed to have a library I p-ut toghether over the of math, science, and engineerng.

Video ganmes did not interest me or philosophy. Periodically I worked problems to stay fresh.

I was certainly not unique among peers. Math and physics was part of the language.

It is easy to scan through something on the net and make generalized statements. Go ahead, post some math.

When reading new theory I first looked at how energy and mass are accounted for, it is called continuity equations. Everything else flows from that.

 

[Swammerdami]

As I understand it Einstein initially rejected Minkowski block world not because he considered it metaphysical — Einstein was a metaphysician as well as a scientist — but precisely because he considered it a mathematical abstraction not connected to reality. Later he seems to have concluded it was correct. But it should be recalled that Einstein was a student of Minknowski, who called Einstein a “lazy dog.” So maybe Einstein’s initial rejection of Minkowski was based on personal animus. Thus we see that not just philosophy, but personal opinions and conflict, can affect science.

Minkowski invented Minkowski space in 1908 in response to Einstein's Special Theory.

Albert Einstein was one of the very greatest geniuses who ever lived, but he was not superlative as a mathematician. He preferred to focus on the simplicity of things. I don't think he argued that Minkowski's ideas were "wrong", just that they were "superfluous." It was only a few years after Minkowski's invention that Einstein realized it was essenial for his General Theory:

I occupy myself now exclusively with the problem of gravitation . One thing is certain that I have never before had to toil anywhere near as much, and that I have been infused with great respect for mathematics, which I had up until now in my naivety looked upon as a pure luxury in its more subtle parts. Compared to this problem. the original theory of relativity is child’s play.

 

[Michael S. Pearl]

If we are going to assert that the future is not yet set, then we need to define whose future we are discussing, because according to GR, my near future could be your recent past.

Right. That's what I was acknowledging when I said "mapping (or locating) occurrences in terms of the relative wheres and whens". Rather than the content, those wheres and whens seem to be more about the shape (so to speak) as seen from different perspectives.

 

[bilby]

Rather than the content, those wheres and whens seem to be more about the shape (so to speak) as seen from different perspectives.

I am afraid I don't have the slightest clue what you mean by "shape" and "content" here, so I don't know what you are trying to say.

 

[Elixir]

Max Tegmark says they are. Others disagree.

It has ever been so. If there is (only) a universe that comports with its own rules, that places us in ignorance. Attribution to unknown things (e.g gods) gives us both an illusion of security and an illusion of power.
In both cases “perception is reality” still rules, in the universe of subjective experience.
Mathematical descriptions of what lies beyond our ability to experience, may be aok, but of what use? If there is more than one way to explain all observations, I figure they’re all wrong anyway.
The BB as a mathematical construct led to the explanation for the “static” of the predicted CMBR, but what differentiated predictions do the various block model variations offer?

 

[Michael S. Pearl]

Rather than the content, those wheres and whens seem to be more about the shape (so to speak) as seen from different perspectives.

I am afraid I don't have the slightest clue what you mean by "shape" and "content" here, so I don't know what you are trying to say.

"Block" in "block universe" refers to a shape. It is supposed as if there is an outside. "Content" would be whatever occurs within any given shape. Even if the "shape" is static, even if the shape is not static but is instead determined to be what it is to be, it does not necessarily follow that what occurs within any such space is also static.

 

[bilby]

Rather than the content, those wheres and whens seem to be more about the shape (so to speak) as seen from different perspectives.

I am afraid I don't have the slightest clue what you mean by "shape" and "content" here, so I don't know what you are trying to say.

"Block" in "block universe" refers to a shape. It is supposed as if there is an outside.

Well, kinda, but not really. The "outside' is hypothetical, and assumes a (non-existent) additional dimension, and a (non-existent) observer with the ability to use that dimension to view the entire thing all at once.

"Content" would be whatever occurs within any given shape. Even if the "shape" is static, even if the shape is not static but is instead determined to be what it is to be, it does not necessarily follow that what occurs within any such space is also static.

Well the whole point of the concept is that it is static. Nothing changes within a block universe, because time is already a part of that universe. From the hypothetical "outside" viewpoint, nothing can move or change.

Within the block, our awareness appears to travel at a constant rate along the t-axis, and follows our personal history in the space dimensions. Whether that's an actual thing, or an illusion, or just another hypothetical, nobody knows. What is awareness anyway?

It seems to me that I was aware for most of my life, so the me of 1995 or 2005 is just as aware as the me of 2025, always "was" and always "will be", The feeling that awareness moves through time would simply be a cognitive error, like the "awareness" that your train is moving when the one on the adjacent track starts to move.

 

[Michael S. Pearl]

The "outside' is hypothetical, and assumes a (non-existent) additional dimension, and a (non-existent) observer with the ability to use that dimension to view the entire thing all at once.

Of course the "outside" is hypothetical. Maybe it is best called flat out imaginary. The "outside" goes along with or follows from the figurative "block" shape as a way of expressing thinking about occurrences occurring "within" the where-when "container" which is the spacetime universe.

Within the spacetime container, use can also made of the light cone shape to indicate a bit about where-when relative accessibilities, but the "all at once" is itself also an hypothetical with regards to the spacetime container. The all at once so as to be a static block is an assumption which might well have circumstantial utility (or maybe just convenience), but such utility would not be sufficient to establish the hypothesis as necessary; it would not be sufficient to establish that what is assumed is necessarily the case.

Obviously.

And this is where we get back to the growing block notion stripped of the problem which results from its expression in terms of what "exists". In the suggested alternative growing block notion, there really is no need of an outside beyond that "outside" which (unfortunately?) follows from maintaining the inherited "block" descriptor. Past and present indicate spacetime container internal perspectives from which contents (occurrences) are set, fixed, utterly determinate so as to be devoid of any indeterminateness whatsoever whereas future is a perspectival indicator of there being a not merely epistemic indeterminateness with regards to what occurrences/contents occur. This could be the case even if the "shape" of the spacetime container were to be utterly determinate/determined without being eternally, perpetually actual so as to be eternally, perpetually static.

 

[bilby]

The "outside' is hypothetical, and assumes a (non-existent) additional dimension, and a (non-existent) observer with the ability to use that dimension to view the entire thing all at once.

Of course the "outside" is hypothetical. Maybe it is best called flat out imaginary. The "outside" goes along with or follows from the figurative "block" shape as a way of expressing thinking about occurrences occurring "within" the where-when "container" which is the spacetime universe.

Within the spacetime container, use can also made of the light cone shape to indicate a bit about where-when relative accessibilities, but the "all at once" is itself also an hypothetical with regards to the spacetime container. The all at once so as to be a static block is an assumption which might well have circumstantial utility (or maybe just convenience), but such utility would not be sufficient to establish the hypothesis as necessary; it would not be sufficient to establish that what is assumed is necessarily the case.

Obviously.

And this is where we get back to the growing block notion stripped of the problem which results from its expression in terms of what "exists". In the suggested alternative growing block notion, there really is no need of an outside beyond that "outside" which (unfortunately?) follows from maintaining the inherited "block" descriptor. Past and present indicate spacetime container internal perspectives from which contents (occurrences) are set, fixed, utterly determinate so as to be devoid of any indeterminateness whatsoever whereas future is a perspectival indicator of there being a not merely epistemic indeterminateness with regards to what occurrences/contents occur. This could be the case even if the "shape" of the spacetime container were to be utterly determinate/determined without being eternally, perpetually actual so as to be eternally, perpetually static.

All of which assumes absolute time - the existence of a "present" agreed upon by all observers, and (as a direct corollary) the fact that all observers agree on the sequence of events.

That assumption contradicts General Relativity, which seems like a very dangerous thing to do without some kind of evidence to justify doing it - GR is very well evidenced indeed, so to deny it requires a bit more than a feeling of unease about its implications, if we are interested in being reasonable about our conjectures.

The sole "evidence" that inspires the idea of replacing the static block with a growing block seems to be that the latter makes people uncomfortable.

Reality has no obligation to make anyone comfortable, nor to be easy or pleasant to contemplate.

 

[Michael S. Pearl]

All of which assumes absolute time - the existence of a "present" agreed upon by all observers, and (as a direct corollary) the fact that all observers agree on the sequence of events.

How/where is such an assumption included?

If the internal perspective is singular (such as that experienced by an individual), then there is no need of an absolute time. An absolute time seems that it would have to hold not only trans-perspectivally but, indeed, over every possible perspective.

But, then, wouldn't that effectively just be another way of re-presenting the static block assumption imagined view from the outside?

Is there some actual perspective from which only the stasis of utter and eternal determinateness is observed?

I could answer my own question with a "not that we know", but, instead, and based upon all reported observations and experiences, it is no less reasonable to answer with a simple "No."

In any event, the relativity of sequences is not sufficient to establish the eternal utter determinateness of all occurrences such as is asserted with the static block time notion. We can see the past (for instance, when we observe stars), but we do not see the future. And maybe that could be because the future is not so utterly determinate as is the past - even if the so-called block "shape" is itself eternally and utterly determinate.

We can certainly say that "our awareness appears to travel at a constant rate along the t-axis" (even if time seems to move faster as we age), and we can think that this awareness might "simply be a cognitive error", because, after all, we are aware of having experienced illusions. But, it sure seems as if it has to be something other than a cognitive error or inability or illusion that explains how it is that we see events from the far away past but not from the future.

I am sure there are all sorts of proposals for explaining how it is that the future is invisible but which proposals remain currently indemonstrable. Still, that is really not the point. The issue regards whether a static (and therefore utterly determinate) block spacetime is necessary even for relativity thinking. And that is to say that static spacetime strikes me as more of a convenient tool for philosophical thinking (including within science) rather than a scientific necessity.

Is the static block spacetime notion a scientific necessity, or is it merely a convention?

 

[bilby]

All of which assumes absolute time - the existence of a "present" agreed upon by all observers, and (as a direct corollary) the fact that all observers agree on the sequence of events.

How/where is such an assumption included?

A "growing block time" has a fixed past, and an uncertain future, with the future becoming fixed (ie becoming the past), at the present.

If there is more than one present, then that's impossible. And as there are as many presents as there are observers, that's impossible.

A growing block that, for observer A, has fixed event X in the immutable past, might, for observer B, have X in the unfixed future. It is therefore internally contradictory to posit a growing block, unless there is an absolute present, agreed to by all observers, with all events being either in the past, or in the future, with every observer agreeing on each and every event's status.

There is no universally agreed "now". It makes no sense to build a model that depends on such a thing - and the "growing block" does depend on exactly that thing.

GR tells us that there is no absolute time; There isn't a universal "now" any more than there's a universal "here" that all observers agree upon.

At what time does the unfixed future become the fixed past, if "now" is entirely subjective?