Is Time Truly an Illusion or a Tangible Reality?

[inflector]

...[snip]...
And QM also seems to give your argument an even bigger problem as non-locality is precisely about spanning the flow of time. You can't imagine a jumble of topologically disconnected spatial frames and still have non-locality find a way through the maze to connect them. And if you can, then the paths aren't topologically broken in the first place because the connecting paths exist.

Sort of like the many worlds argument. How can that be rendered than other as a topologically branching tree?

I know the above excerpt is from a few months back, however, as I have just for the first time read this quote, I wanted to make sure I understand it correctly.

First, you say:

You can't imagine a jumble of topologically disconnected spatial frames and still have non-locality find a way through the maze to connect them. And if you can, then the paths aren't topologically broken in the first place because the connecting paths exist.

What precisely do you mean by topologically disconnected spatial frames? Do you mean that there is no causal connection between the frames?

Could it not be the case where spacetime is very much like a tree where the connections that are causally constrained at the speed limit of C would be those defined as traversing up, down, and across the branches of the tree itself. But as with an actual tree, branches from one major bough often brush up against branches from another bough thereby bypassing the normal connection/causality speed limit? Is it not possible that non-local interactions are caused by these sorts of temporary connections between otherwise topologically disconnected spatial frames?

 

[Max™]

Actually, you never perceive "now". No one does. It takes a bit of time for all the information from "now" to flow through your sensory systems and be processed by your brain to have the "now" experience, and by then, it's gone. So there's always a bit of lag.

Well, I do perceive "now", I'm merely aware that I do a few fractions of a second after the moment which I labeled as the present.

Is there anything meaningful in saying one person's experience at moment x was different than another person's experience at moment x?

If I am attempting to define a general plane of simultaneity for Earth bound observers, I suppose there is?

We're close enough spatially, and in similar enough states of motion that the discontinuity between what I claim is a set of simultaneous events will differ little from the set you claim, only at the most distant fringes of our observable portions of the universe would we be likely to notice such small variations.

The moment when you read this, is roughly the same instant as a bird landing on a branch outside your window, as a car accident in Calcutta, as me scratching my ear upstairs.

Tomorrow, when I check back on this thread, this moment when I read these words I wrote a day before will seem like "now" to me, but I am aware as I write them that it is off that way *motions vaguely in the downstream direction of time*, or more accurately, I am aware that it can only be off in that direction, towards what I would label the future.

It is possible that I might be killed before I get a chance to fulfill that little bit of prophetic self-interaction, or the computer could crash, these boards could lose the post, or any number of different things could prevent my reading this post tomorrow.

Why would reading things you wrote in the past seem like "now"? That might be something unique to your perspective.

When I re-read the bit I quoted inside your quote here, it felt like "now", does that explain what I was saying better?

Which raises another interesting question, why can we only recall what we did in the past?

Why don't purple monkeys fly out of my butt? Who knows. It's just the way things work. Your brain can't make a memory out of events your sensory apparatus hasn't come into contact with yet.

I can't technically observe the past from my perspective either, I'm just aware that it exists due to information which I identify as having been stored in my brain at a prior date.

I am aware that the future exists as well, though I can not observe it from my perspective either.

It isn't as simple as "it's just how things work", maybe that works for you, I've never liked "just because" type answers myself.

I can not directly observe the moments when I posted in this thread yesterday, though I do hold information about them, and can even relive them to some extent by reading the post again.

I know that tomorrow from my perspective must be further downstream in time from the point I am viewing, yet I do not have information about that event, and can only relive it in my imagination.

Something interesting to think about, when I get around to thinking about it, that is.

OK, but I still don't see where you aren't just restating the obvious.

Perhaps I didn't make my point as obvious as you thought?

There is no requirement for the three spatial dimensions we observe to have a particular axis of interaction. If I move to the right, that does not require that I was moving from the left at some prior point. If I move further to the right, it does not mean I have to continue going that way. If I wish to stop moving to the right at a given speed, I can do so.

Yet, I am aware of what I find best described as motion through time, but I am unable to stop, or change direction... and even then, describing time as just a different type of spatial direction makes me want to ask silly questions.

What is the speed of left, for example?

 

[apeiron]

What precisely do you mean by topologically disconnected spatial frames? Do you mean that there is no causal connection between the frames?

I was arguing that if they were disconnected, then it seems by definition there could be no causal linkage. Otherwise - even just with nonlocal effects - there is a link of some kind.

Could it not be the case where spacetime is very much like a tree where the connections that are causally constrained at the speed limit of C would be those defined as traversing up, down, and across the branches of the tree itself. But as with an actual tree, branches from one major bough often brush up against branches from another bough thereby bypassing the normal connection/causality speed limit? Is it not possible that non-local interactions are caused by these sorts of temporary connections between otherwise topologically disconnected spatial frames?

If two branching histories touch, then by this analogy where they touched they would share the same light cone surely?

 

[inflector]

If two branching histories touch, then by this analogy where they touched they would share the same light cone surely?

Well, I was thinking that they wouldn't share the same light cone. That's why I thought this could be a mechanism for non-local interaction which seems to be present in quantum entanglement, for example.

To me, nonlocal implies non-overlapping light cones, but perhaps I have this wrong.

I've been thinking about weird topologies for spacetime that would make nonlocal correlations possible using a realist perspective. A topology/geometry that would allow a dBB interpretation of quantum mechanics to meld with general relativity. A lost cause perhaps, I know, but hey, I've always liked working on the impossible.

 

[apeiron]

To me, nonlocal implies non-overlapping light cones, but perhaps I have this wrong.

I might misunderstand you, but my view is that a non-local entanglement, as thought of in EPR, would look like two events on opposite sides of the same light cone, or branch-lets of the same bough in your analogy.

So the paradox is not that there is entanglement (because there is a shared event in the past of the two later events - the moment that created their entanglement) but that then there can be some non-local constraint that acts "instantly" to span the full width of the lightcone. So observe a particle's spin on one side, and it determines also the spin on the other side of the light cone.

In your analogy, if one bough touches another (the equivalent of an observer measuring the spin of one particle) then branchlets over the far side of the bough also shiver with that touch.

And indeed, this would be an accurate portrayal I would think. Decoherence would travel in timeless fashion to constrain everything within the light cone. The tree branch analogy might even have the advantage of giving the image of the path by which things "travel all the way back to the fork and back up the other side" rather than the alternative view of a constraint acting "instantly" across the current breadth of the light cone.

I've been thinking about weird topologies for spacetime that would make nonlocal correlations possible using a realist perspective. A topology/geometry that would allow a dBB interpretation of quantum mechanics to meld with general relativity. A lost cause perhaps, I know, but hey, I've always liked working on the impossible.

The idea of fractal branching seems to me a very natural one as it gives you an actual mathematical representation of dissipative structures - it is how entropy spreads out to fill a space of the possible. So as a "weird topology" it is in fact well motivated and quite realistic.

But again, when it comes to QM, I would see the collapse of a wave function in sum over histories terms. So before collapse, the lightcone of an event was in an indeterminate state in which "anything" was possible. After the collapse, you have some actual determined path (a branch representing a thermalising event) plus all the "air" around the branch, which is now the equally definite places within the lightcone where the event did not happen.

So nonlocality can either be seen as a constraint that "jumped instantly" across the lightcone, or instead - using the branching analogy - that the nonlocality is written into the branching structure itself. The entirety of the branch was decohered - all the way back in time to its origin - at the "moment" of observation (the brush of one branch against another).

 

[petm1]

I can't technically observe the past from my perspective either, I'm just aware that it exists due to information which I identify as having been stored in my brain at a prior date.

I am aware that the future exists as well, though I can not observe it from my perspective either.

All I see is the past, formed within my eye as an image. This image is what I think of as the leading edge of my "now", a one second frame that I will only lose upon my death. What is "real" funny to me, is that what I think of as the future are the same signals that make up this image from the past I see as the present.

 

[ThomasT]

So nonlocality can either be seen as a constraint that "jumped instantly" across the lightcone, or instead - using the branching analogy - that the nonlocality is written into the branching structure itself. The entirety of the branch was decohered - all the way back in time to its origin - at the "moment" of observation (the brush of one branch against another).

Your discussion of branching topologies is over my head, but wrt the applicability of nonlocality to the OP's question my first thought is that since there really isn't what I would call a significant difference between local realist models of entanglement and the quantitative results, I think it's a bit early to start speculating from the assumption that reality is nonlocal.

To answer the question in the title of the thread we just need to objectively define the terms reality and time. Such definitions do exist, and from them it follows that it's correct to say that time is real.

Of course, given the inferential speculative possibilities of modern physics, there's much more that can be said wrt the OP's considerations. And, as usual, after reading what several posters have had to say on this, I'm thoroughly confused again.

 

[petm1]

can I not determine an absolute definition of simultaneous events, and thus destroy the very foundations of relativity?

The very foundation of relativity lies in the the little twist called big bang, this one event and when it flew apart, it was simultaneous motion that was lost in space.

 

[Max™]

The very foundation of relativity lies in the the little twist called big bang, this one event and when it flew apart, it was simultaneous motion that was lost in space.

Twas a rhetorical question, I'm pretty well informed regarding relativity.

 

[petm1]

Twas a rhetorical question, I'm pretty well informed regarding relativity.

Sorry, did not mean to offend with my light joke.

 

[inflector]

I might misunderstand you, but my view is that a non-local entanglement, as thought of in EPR, would look like two events on opposite sides of the same light cone, or branch-lets of the same bough in your analogy.

That makes sense. I was viewing the light cones of the two measurements as two separate light cones.

Clearly, the light cone of the entangling photon generating event contains the two photons as they are measured.

In your analogy, if one bough touches another (the equivalent of an observer measuring the spin of one particle) then branchlets over the far side of the bough also shiver with that touch.

And indeed, this would be an accurate portrayal I would think. Decoherence would travel in timeless fashion to constrain everything within the light cone. The tree branch analogy might even have the advantage of giving the image of the path by which things "travel all the way back to the fork and back up the other side" rather than the alternative view of a constraint acting "instantly" across the current breadth of the light cone.

I'm just thinking of possibilities for the observed nonlocal behavior. So the tree analogy gives two separate potential approaches, touching branches and decoherence traveling up and down the branches in some superluminal fashion.

So nonlocality can either be seen as a constraint that "jumped instantly" across the lightcone, or instead - using the branching analogy - that the nonlocality is written into the branching structure itself. The entirety of the branch was decohered - all the way back in time to its origin - at the "moment" of observation (the brush of one branch against another).

Either one of these options is one that merits further thought. The possibility (however slight) that there could be some realistic explanation is what keeps me working on these sorts of ideas.

 

[Descartz2000]

I have seen several responses here that claim the present is all that is real and true. I agree with this, but every state is a present state. So, more accurately I can't claim that this particular 'now' state is only real and true. When any state is in a physical form and in a specific set of configurations, it is physically present and real. But, this logic applies to all states. So, when I claim, "my present moment 'now' as I write this is most real", I am in error because the same logic applies to all observed states. So, the viewpoint of 'now' carries no extra value than the viewpoint of yesterday's 'now' observation. So, inherently all 'now' states are equal. Therefore, I can't claim this 'now' state is more real than a perceived 'past' or 'future' state, because they all carry the same value and logical principles.

 

[Descartz2000]

If you believe that the state of things has to be crisp and definite - something either is or it isn't - then you indeed face a logical bind. Past and future are either states that are - which ends up in the deterministic block time view where the now is an illusion - or instead only the now is real, which makes past and future the illusion.

So yes, think that way and you are trapped into mutually contradicting positions, neither of which feels right.

Which is why I stressed the further dimension to reality, the dimension of development that runs from the vague to the crisp, from becoming to being, possibility to actuality, etc. This is a traditonal idea in metaphysics even if it has become largely lost in physics.

So the past is definite (it cannot be changed) while the future is indefinite (it is still full of vague potential, a capacity for change, while also of course highly constrained because of a weight of accumulated history).

The best kind of model of this could be a scalefree network or other "edge of chaos" model where the "now" is a mix of past and future - a powerlaw mixture of the changed and the changing, islands of stasis and flux.

Look inside the "now" of the universe - which can be measured in a general way by its current temperature - and you will be able to see that it is in fact an average of local "nows".

This follows from the transactional interpretation of QM, a la Cramer, I believe.

I don't understand where the contradiction lies. Why shouldn't things be crisp and definite especially when we are talking about the macro world? Leaving QM aside, I think on the large scale most things and events are deterministic, maybe not predictable, but deterministic. So, where is this area of non 'crispness' that you talk about especially when we are referring to everyday real world events? The future is not 'open' so to speak, at least no objectively. It is open from your perspective of 'now', but this viewpoint is not preferred over any other viewpoint. If it is 'open', then your viewpoint of 'now' is more valid of a perspective, than your viewpoint in the future. yet, this is incorrect. According to Relativity, no 'now' state is more valid than any other.

 

[apeiron]

I think on the large scale most things and events are deterministic, maybe not predictable, but deterministic. So, where is this area of non 'crispness' that you talk about especially when we are referring to everyday real world events? The future is not 'open' so to speak, at least no objectively. It is open from your perspective of 'now', but this viewpoint is not preferred over any other viewpoint. If it is 'open', then your viewpoint of 'now' is more valid of a perspective, than your viewpoint in the future. yet, this is incorrect.

Take a seed. It could turn into many different potential trees - different branching patterns depending on the vagaries of soil, weather, disease, angle of sun and wind, competition from other trees. So its future state is relatively unconstrained in some regards. Its future is broadly determined (by its genetic history, an accumulation of past information) but is open, indeterminate, in its detail.

According to Relativity, no 'now' state is more valid than any other.

Yes, but this is just because time is modeled as a locally reversible or symmetric dimension. It leaves out any attempt to represent an arrow of time, a gradient. So relativity may tell the truth, but not the whole truth!