A misconception in a post from another thread:

It is one of the most fundamental aspects of our experience, that past events are substantially different from future events. Past events cannot be changed, while we can influence the occurrence of future events. — Metaphysician Undercover

This is a feature of your future light cone. That cone, not the present, delimits events which can and cannot be changed.
Similarly, the past light cone, not the present, delimits that about which we can know (events which can have an effect on us, vs those which cannot).

Neither of these fundamental things changes at the boundary of the present, except where the two cones happen to intersect the present. So no fundamental change as described here occurs at the present.

Those light cones are not frame dependent. They are 'determinate' as you put it.

I don't see why presentism requires a preferred reference frame. When we as human beings meet together, and communicate, we call this the present. We only need to produce a reference frame if we want to measure the passing of time. Presentism doesn't necessarily require this, so it doesn't require a preferred reference frame. — Metaphysician Undercover

I think you have a different concept of presentism than the one typically presented on philosophy sites, which might ask when the twins get back together and notice 10 or 20 years elapsed, isn't one of them more correct about how many years actually went by? Presentism would say yes to that, but you seem to say no, since a different amount time passed for each of them, so they're both right about it.

A "preferred foliation" might validate determinacy in time, if the preferred foliation was justified, not arbitrary. But if the preferred foliation were justified, wouldn't special relativity be contradicted? — Metaphysician Undercover

Determinacy is unaffected by any choice of foliation. Different frames of reference do not in any way alter the causal relationship between any two events.
SR just says no preferred folation is locally detectable. It doesn't forbid its existence.

Right, there is a combined value of time and space. However, since what is actually measured by us, according to our capacities, is time, and space independently, and these are indeterminate, then the combined value is fundamentally indeterminate. — Metaphysician Undercover

You seem to use 'indeterminate' as 'not absolute'. The word means 'uncalculable', or 'unpredictable', and as Terrapin has been trying to point out, it is quite calculable. These things are just frame dependent, but completely determined given a choice of frames.
That said, time and space between any two events is indeed frame dependent, but their combination always yields the same interval. That part is thus frame independent. The interval between any two events can be given by one fixed value, and different perspectives do not change that value.

If I assumed a "Master Time", then I couldn't conclude that time is indeterminate. — Metaphysician Undercover

It is called a preferred reference frame, or at least a preferred foliation (an objective ordering of events). Presentism must assume such a thing, but the existence of a preferred foliation does not necessarily imply the existence of a present (a preferred moment).

Anyway, under the preferred foliation, there is a fixed amount of time between any two moments in time, and frames which do not correspond to this preferred frame are simply not representative of the absolute ordering of events. Hence clocks are all wrong because they're all dilated, some more than others.

Can I make the further, more generalized conclusion, that the amount of time between any two points in time, is indeterminate? — Metaphysician Undercover

In the spacetime model, there is no concept of 'point in time'. Time is just one of 4 dimension, all of which need to be specified to identify a point, which is called an event. There is a fixed (frame independent) separation of any two events, but that separation is called the interval, not the duration between them. Both the time and the space between any two events is frame dependent (indeterminate), but the combination of the two (the interval) is always the same.

A lot of what was just posted can be illustrated with the balloon analogy.

The universe is like the balloon, with the galaxies painted on it, moving around a bit, but generally moving away from each other as the balloon expands. oom in and there is you and I on it.

Presentism says the the balloon is like, well a balloon, without an interior. Only the present surface is the actual part of the balloon. Eternalism says that all of the space, both interior and exterior points are part of the object. There is no surface to the thing at all, defining points that are interior or exterior. Growing block says it is a solid sphere, with an outside surface, but points outside of that are not part of the object.
I find these all to be metaphysical differences, but others do not. My claim for my stance there is that there are no empirical distinctions between these three scenarios.

The metaphysical claim that the object exists independent of observation is a different claim, and can be claimed or denied by all three scenarios. The object, whatever its nature, exists or not. Again, this is metaphysical since again, there are no empirical distinctions between these two scenarios.

We know that an objective present cannot exist because the clocks disagree. All there can be are relative presents. — Inis

No clock or other device measures objective time, so this doesn't follow. All clocks run slow, and some slower than others, so it is to be expected that they don't always agree.

Eternalism isn't metaphysical if it's part of our best physical theories. — Inis

I don't think any of those theories assert it, despite the typical interpretation of relativity. I know Einstein held eternalist views due to the implications of the theory, but that's mostly because it is the simpler view, without a needless addition that adds nothing to the theory.

Anyway, relativity doesn't make any references to 'the present', but doesn't deny it either. It actually (reluctantly) acknowledges a preferred foliation, which can be interpreted as relativity supporting at least one aspect of presentism. Still, an objective ordering of events is not an assertion of the existence (or lack of it) of a present, which makes no empirical predictions.

Both general relativity and quantum mechanics tell us that the universe as a whole is at rest. This was realised early on in GR but took a while to be understood in QM.

This means that presentism isn't metaphysical either, it's just wrong.

I actually don't follow what you're trying to say here. I don't know what it would mean to say that the universe is not at rest (has a nonzero velocity???), so there doesn't seem to be any meaning to saying it is at rest.
Then you say this makes presentism wrong, and I don't see the connection.

I like good arguments against presentism, and I even have a unique one of my own, but I think they're all faulty.

What is metaphysical, however, is the claim that an objective observer-independent Reality exists.

Yes, that would be a metaphysical claim, and one independent of the eteralism/presentism debate. The latter concerns the nature of the universe (is it 3D or 4D?), but the former is something deeper, and seems to rest on a sort of undefined meaning of 'exists'. Being a relativist, I don't make sense of something being said to just 'exist'. It exists in relation to something (which need not be an observer), and I'm not sure in relation to what the universe might be said to exist or not exist. So such statements need to be defined by those that makes such statements.

If you take the view that reality is observer-dependent, then presentism may be rehabilitated, but at what cost?

If 'I' am an observation, that observation is taken at some event, and that means 'I' am an event, in relation which 'the present' very much has meaning. If 'I' constitutes a defined series of specific events, then those events are not simultaneous and none of the events is more special than any of the others, except perhaps the two endpoints. 'The present' could still be defined as the last event of the series of events that defines 'I'. Presentism is not wrong there, and the cost doesn't seem too high.
Notice that it is sort of an idealistic view. 'I' defines the present, not the other way around. That's a bit of cost I think.

One clock runs slower than the other. — noAxioms

I'm not sure how this relates to what I've said. — Luke

Apparently I was responding to a different quote, the one just below the one quoted in that response. It is about how time dilation doesn't invalidate presentism.
That's two posting mistakes I've made now.

Again, I think we need to assume presentism (or that "the A theory of time is correct") for the purposes of the topic of this discussion. However, if you all just want to discuss the failings of presentism then have at it.

Presentism and Eternalism are two different metaphyscial interpretations of the same empirical data. Since time travel would be an empirical experience, it should in principle make zero difference whether presentism or eternalism is assumed. Under current empirical physics, both metaphysical views forbid time travel to the past, and neither forbids forward travel. Hence I see little point in needing to assume one metaphysical stance when discussing if a physical act is possibility or not.

I don't see how the reading on the clock has anything to do with whether or not the present exists. — Metaphysician Undercover

Hey, we actually agree on a point...

My bad. I read your comment as suggesting that they didn't run at the same rate.

What do you mean "they rewind"? — SophistiCat

Well, I buy into neither presentism nor time travel, so I'm trying to imagine how a presentist would envision travel to a time that is no longer existent. Somehow you need to find yourself in a world with the state being some prior state except for you being in it, which sort of seems to require a physical rewind of all state (except the part where 'you' appears in it), thus dragging the present back to that prior time. It really makes no sense to me, but it makes no sense in the block view either, so go figure.

The idea of time travel is that someone (or something) is moving in time (at a different than normal rate), while everyone and everything else goes on as if nothing happened.

Well relativity gets you that, and it even looks normal to the 'travelling' person.

But how this divergence is possible if there is only one now is something I can't wrap my head around. It would make sense if now diverged as well.

I don't think it makes sense for a presentist to propose a divergence of time. A divergence of worlds, sure. That avoids some paradoxes, but time going forward for Fred but backwards for me in my machine, no. If my machine does that, then it just creates a new world now that looks like my old world did X years ago, without actually alter the course of 'the present'.

As I said, it is actually quite easy to achieve time travel in the forward direction (clock moving at other than the usual subjective rate). You can do it with anesthesia or cryonics. The former doesn't halt aging like the latter does. They can also just manufacture a new 'you' a thousand years from now, which is possible at a biological level but probably not a molecular level, and certainly not subatomic.
The subjective experience is fairly similar for all three. You look at a clock, there is a discontinuity, and suddenly the date on the wall is different. It may or may not involve a feeling of 'waking up'. This differs from sleep where there is a definite subjective sense of how long you've been out.

None of these methods work with a negative time rate. Travel to the past is just nice fiction, despite quantum experiments that can be interpreted as cause well after effect.

How about doing a simple time dilation experiment? Synchronise atomic clocks, and take one on a flight around the world. When the clocks are reunited, they no longer agree on the time. How is that possible under presentism? — Inis

One clock runs slower than the other. Neither of them tracks the pace of the advancement of the present. If there was a device that could do that, you'd have your empirical evidence for the view.

Clocks in different time zones don't run at different rates. — Inis

Yes they do, all other factors being equal.

Edit: I read this last comment wrong. Negate this reply....

"I presume you ride the 'now' into the future. That's how it worked. To travel to the past, I suppose you'd have to get time to go the other way, and still be able to ride it, but leaving everybody else behind."
— noAxioms

This works for the Traveler, but what about the rest of us? What happens to us and our now when the Traveler departs into the future or the past, and now departs with him? — SophistiCat

Well, they 'rewind' along with the rest of 'history', which isn't even a violation of physics. Only what you (the 'traveler') are doing is a violation.

We can imagine a world in which, in the year 2019, you stepped into the time machine and suddenly disappeared. Earlier, in the year 1919, an exact copy of you as of 2019 suddenly appeared in a field, fooled around for, say, a week, and then disappeared. Meanwhile, in the year 2019, five minutes after vanishing in the time machine, you reappear, having the memories and other physical changes that your copy had in 1919 at the time of disappearance.

Pretty much the standard depiction, yes. I think Back to the Future did almost exactly this.
The story typically involves a vehicle, emphasizing that it takes to 'the past' like that is a place. Nobody does it with a say a pill or scan-and-teleport with reverse causality. Tron and Star Trek sort of do the scan depiction, but to a different place, not to the past.
Some depictions just have a device like a wristwatch that does the job for you. Some depict a portal that requires a receiving portal on the other side.

We could tell the same story chronologically, without jumping back and forth between 2019 and 1919. The reason we usually tell these stories achronologically is to emphasize causal connections. But in this telling there are no anomalous causal connections between the past and the future - and that is why it does not count as time travel. Time travel is all about anomalous causality.

I think it very much counts if there is a guy in 1919 with memory of 2019. The way you tell the story puts emphasis where the storyteller wants it, but there would be little dispute of time travel to somebody with such memories in 1919, however little he might be able to convince the locals there.

Thinking a bit more about this, if now is an objective fact on presentism, and the Time Traveler is transported some ways into the past or the future, what happens with the now? — SophistiCat

I presume you ride the 'now' into the future. That's how it worked. To travel to the past, I suppose you'd have to get time to go the other way, and still be able to ride it, but leaving everybody else behind.

In more objective terms, I think time travel to the past would be to cause an instance of 'yourself' to exist at time X, but with memory of time Y, with Y > X. This is pretty easy to do in theory in the forward direction, but not so much backwards, being a violation of the principle of locality.

normal "time travel" when everyone moves forward into the future in lockstep at 1 second per second — SophistiCat

I always wondered what meaning there is being a unit of X per X, which seems to reduce to just unitless '1'. On the other hand, our clocks are dilated mostly due to the gravity well in which we find ourselves, so maybe the rate is still unitless, but still less than 1. How much less is an eye-opening exercise.

You need presentism of course. Travel isn't possible at all in eternalism, given the usual A-definition of 'travel'. I plan to travel to 2024, but it will take me 5 years to do it.

So why did you start the B-theory thread about free will and then totally abandon it? It degenerated into the usualy discussion of what eternalism is rather than its implications.

Suppose I am an ontological nihilist who believes that nothing exists, including events. In that sense, all events have the same ontological status, that of not existing. Would that count as "eternalism" then under your view? — Mr Bee

If there is no distinction between the present and other times, then yes.
I'm no nihilist, but rather a relativist, so I think 'to exist' is a relation between things, not a property. So the moon may exist to me, but that doesn't make it just 'exist', which I find to be meaningless.

there simply is no choice but to be a B-theorist since the discovery of relativity. Presentism simply doesn't work. — Inis

I've defended the opposite side of that argument. I don't think relativity contradicts presentism, however much I think presentism is nonsense. The two view make all the same empirical predictions, and theory of relativity is an empirical theory, not a metaphysical interpretation.

Then again, I sort of thought of my own 'disproof' of presentism that basically demonstrates that if time flows, then actual time (not dilated by either speed or gravity) must flow infinitely fast, or our time (clocks on earth) are all stopped. Since presentism does not assert finite flow of actual time, my demonstration fails to disprove presentism.

The reason why I have been using "currently" is because that is the only way I can make sense of your claims, but I very much welcome an alternative conception, so long as it makes sense. Indeed, that is the very reason why I am having this discussion with you. — Mr Bee

Best I can explain the general stance is that eternalism gives equal ontological status to all events. What that status is isn't necessarily part of the view. My opinion on that is certainly not typical of eternalists.

As for tenseless (B-series) language, that just means that a statement about something (an event say) in what I will call spacetime does not carry an implied ordering relation with some second event. It's not that events cannot be ordered, but rather that there is no second event referenced by the statement.

Under A-series language, a similar statement typically has an implied reference to a second event, most often the event of the making of the statement. There really isn't spacetime under presentism, only space.

We're sort of getting off topic here, but the OP has not chimed in to his own thread ever, so I've been going along with this discussion instead. The OP was about how such concepts as determinism and free will fit into a block view of things.

If I say a T-Rex exists, I mean it is a member of the set of objects contained in the universe. I don't mean it is a member of the set of objects currently contained in the universe. — noAxioms

I still do not see how you're using the term "is" in a manner that isn't present tensed though. Also what exactly is in the "set of objects contained in the universe"? I assume that it is going to contain the set of objects that are currently contained in the universe. — Mr Bee

I thought I was pretty explicit in my comment there, so you either have no understanding, or you refuse to accept the way I am using the word. By your insistence in adding 'currently', you are assuming presentism, so of course non-presentism isn't going to be compatible with that.

So you're not trying to drive it to self-inconsistency, but merely decline to accept it, which is fine.

My question is what other meaning of "exists" could there be if it doesn't refer to "presently existing", "did exist" or "will exist". — Mr Bee

All three of those are circular definitions, and thus not really definitions. — noAxioms

How so? What's so circular about them? — Mr Bee

The fact that 'exist' appears on both sides. 'Exist' means 'presently existing'. 'Hot' means has a hot temperature. Those are useless circular definitions.

It means 'is a member of' [the universe], and not just 'is a current member of'. — noAxioms

What does "is" mean here?

If I say a T-Rex exists, I mean it is a member of the set of objects contained in the universe. I don't mean it is a member of the set of objects currently contained in the universe.

I have an understanding of the B-theory and the A-theory of time which I believe captures the essence what most people understand the view to be. That version of the B-theory I also happen to disagree with but that is not something I will go into here. — Mr Bee

I dislike calling it B-theory since that name includes growing block view, which is still presentism.
I'm an eternalist, not just a B-theorist.

My question is what other meaning of "exists" could there be if it doesn't refer to "presently existing", "did exist" or "will exist".

All three of those are circular definitions, and thus not really definitions.
I did my best to describe how I use the word in the tail of my prior post. You didn't comment on it.

What I am saying is that first part of your sentence, that there is no "present" or "now" doesn't make sense. There is no meaning to the idea that the "block universe exists" without stating that it either exists now, did exist, or will exist. — Mr Bee

I can agree that I find little meaning to the block universe existing or not. I see no need for distinction between the two. But as for the run of the mill B-theorist, they'd not ever say that the universe exists now, or it once existed, or will exist. Any of those is like saying it is located to the left of the invisible pink unicorn: a relation with an entity not acknowledged.

Just look at our conversation right now, for instance which is embedded in the now.

History is littered with such statements. Are you the only one that is correct about it?
I'm not saying it is wrong for a B-theorist to use tensed verbs in everyday language. They serve a very useful purpose. But describing the universe in the same manner as an object existing within the universe is wrong. I think a lot of people see the universe as an object like that, coming into being somehow from non-being, just like every actual object in the universe. I don't. I think it contradicts what a universe should be.

Are you saying you don't understand the view or you simply disagree with it? It's hard to tell from your posts. T-S obviously doesn't understand it, arguing inconsistency with premises the view doesn't make.

As a result, I believe that all views about time are "presentist" to the extent that everything that is said to "exist" is presently existing. It is sort of trivial, but that is what "exists" technically means (as again, it is a present tense term).

Fine. Pick another word, and that word also probably should not be used, since it is a word used for objects. Does the last ice age exist? It is part of the history of Earth, as is the process where the sun swallows it. You seem to want a different word since you disapprove of it being said that those events 'exist' in the same way that I exist. Then I would still balk at that same word being used to say that the universe exists, since it doesn't seem to be an event or a created object or anything.

I like 'exists'. Both those events above are present in the block, so I don't see anything wrong with using the word. It means 'is a member of' [the universe], and not just 'is a current member of'. The block is not present in the block, so it seems quite circular/incoherent to say the block exists in that way.

Well, what sort of non A-series terms are there? — Mr Bee

No tensed verbs for starters. The universe cannot be a created object for instance. There is no 'there was no universe, and then later there was'. If that happens, there are two kinds of time, and you're talking a different view. The other kind if time is the one that the deity lives in, except then the deity lives within something he didn't create, so that's a problem, but not my problem.

I actually think the attempt to remove A-series terms from a description of the B-series is what leads to nonsense (such as this whole "triviality problem" that people are currently discussing about the A vs. B theories of time). Just take what you said later as an example:

The block view just is (my emphasis).
— noAxioms

What could the "is" mean other than that it is present, or that it exists now (both being A-series terms)?

There is no 'the present' or 'now' in the view, so I'm not sure what is being referred to with that comment. OK, you use 'present' as a verb, so perhaps you mean some other declaration of being. To be honest, the view doesn't assert 'presence' at all since none of the view seems to require it. The angles of a square are all right angles whether or not the square is present. I've thus never really asserted it. I'm quite in the minority on that point since everybody presumes that presence, but it is a premise, not something that can be proven without assuming the conclusion.

So I don't mean hardly anything when I say it 'just is'. I don't feel I have to.

Of course, I imagine you don't want to say that you mean that by your use of the term, but what else could it possibly be? A tenseless use of the term? What could that possibly mean?

B-series descriptions should simply not make reference to the present, which has no meaning in the view. All of Terrapin Station's comments made reference to it, so they're A-descriptions.

Now as for my own views on the matter, I think that the B-theory of time does make alot of A-series terms irrelevant, but does not eliminate them altogether. The idea that things "will happen" or "did happen" make no sense in a world where time doesn't pass.

I've also seen 'proofs' that the presentist view cannot be, but they all seem to be faulty.
I have my own, one I've not seen elsewhere, but in the end I make presentism pretty silly, but not impossible.

You can't get outside of it with because either the block of time always was there or there was nothing and then time suddenly appeared. — Terrapin Station

That would be two times: The one in which the block is created, and another that is a dimension of the block. Eternalism is not a view of there being two kinds of time.

I really don't care if you understand it or not. The comment was directed to the OP as an example of what happens when you mix both views as you continue to do.

A-series terms which leads to nonsense when discussing a B-series view. So "could have done otherwise" is an example of an A version of the definition. — noAxioms

An example below:

With B time, you still have the problem (for intuition) that it either appeared "out of nowhere" or always existed. — Terrapin Station

Both "appeared out of nowhere" and "always existed" are A-series references, which of course are incompatible with B series. The block view just is. There is no 'beginning to exist' of it, because that puts time outside the block, which is not how the view depicts time.

I think a lot depends on you definition of free will, and a stance on theory of mind, and not so much if determinism is true.

As for determinism, it depends a lot on your QM interpretation: The cat is both dead and alive, and it is probably (Bohmian mechanics excepted) not determined what will be seen when you look at the cat. But unless you can will the cat to be alive or dead, it seems like determinism or lack of it plays an insignificant role in the debate.

As for definition of free will, that is usually given in A-series terms which leads to nonsense when discussing a B-series view. So "could have done otherwise" is an example of an A version of the definition.

My point: Get the ducks in a row first before you draw conclusions, else the discussions go past each other as people are working off different premises.

One key principle upon which special theory of relativity rests, is the relativity of simultaneity. As I explained above, it is an ontological principle. — Metaphysician Undercover

As an ontological principle, it demands a preferred frame. Without that, two events cannot be actually simultaneous. TOR does not assert that preferred frame, so it makes no such ontological assertion.

Also, while it does describe relative simultaneity, but it doesn't rest on that. It is a conclusion that follows from the constant speed of light measured against any frame.

In general, competing ontological principles are incompatible and there is no easy test to falsify one or the other. — Metaphysician Undercover

Agree, but theory of relativity is not an ontological principle. The standard interpretation is, but you can't use its premises in a different interpretation.

As for Devans99's bit about assuming God is constrained by materialistic rules, the typical theist isn't even willing to assume humans are constrained by materialistic rules, so it seems pretty contrary to constrain God more than we constrain ourselves. I agree with your reply to that remark.

No, it is an incorrect interpretation of special relativity. Special relativity cannot be interpreted as allowing for only one present. — Metaphysician Undercover

If you insist. Seems to put your presentism on shaky ground then, if relativity contradicts it. It requires you to reject it. Seems harsh.

Either you take the standard interpretation that there is no such thing as the present (eternalism), or if you approach with the assumption that there must be such a thing as "the present", then you find a multiplicity of presents.

Well, I stand on the eternalism side of that fence, so it would not bother me to see presentism be contradictory like that, but since I cannot think of a single falsification test for it, I suspect your analysis is in error. If they're incompatible, there must be some test that falsifies one or the other.

Right, that's why the standard interpretation is that of eternalism, no "now". — Metaphysician Undercover

Standard interpretation, yes, but not the only one.

That is incorrect. If you interpret special relativity with the assumption that there is such a thing as "the present", then "the present" is necessarily specific to the frame of reference. This means that there are multiple "presents" according to multiple frames of reference. Furthermore, events which are simultaneous in other frames, are really simultaneous in those frames. To say this, what you say here, that moments which appear to be simultaneous in other frames "are not really simultaneous" is to violate special relativity which stipulates that they really are simultaneous, according to the frame of reference.

I think what you're described here is an inconsistent set of assertions. You describe an assertion of "the present" like there is one of them, and then go on to describe other different presents, which means there is more than one. That is inconsistent, unless I'm interpreting your words wrong.

For what I said to be incorrect, it would similarly need to be self-inconsistent.

Again this is the same incorrect assumption. Special relativity, like all relativity theories, dictates that there is no ontologically "correct" frame.

It uses the word 'ontological'? That would be news to me. That would indeed be a metaphyscial statement.

I thought that Special Relativity implied Eternalism — Devans99

It probably does imply it, but does not assert it.

If you interpret it that way (as did Einstein), then it would be logically inconsistent with "There is something that distinguishes 'now' from 'past' and 'present'"

Special Relativity asserts the existence of multiple 'nows'

No, this is blatantly false.

I disagree; Eternalism is primarily about the existence of past and future.

Also false. It has gives no such distinct status to any event. None of them are 'past' or 'future'. Such labels are only potential relations between two arbitrary events. A preferred frame makes that relation objective, not just potential. Presentism on the other hand makes those labels a property of an event, not a relation between two of them.

If both the following hold true:

- Einstein's Relativity is correct
- There is something that distinguishes 'now' from 'past' and 'future'

Then we need a flavour of eternalism that distinguishes 'now'. — Devans99

Einstein did not assert eternalism in his TOR. I know he held that metaphysical view personally, but the theory was about empirical physics, not metaphysics. The theory is about the map, and the metaphyics is about the territory. Einstein stated that a spacetime map corresponds very well to what we observe, but the theory makes no assertions about the correspondence of that map to the metaphysical territory.

If you assert a 'now', then you are discarding the eternal view whose sole premise is non-reality of that very thing. Einstein's theory still stands, but you've added two new things to it: A preferred frame and also a preferred moment. Einstein's theory says the former would be undetectable and makes no mention of the latter.

I'm repeating myself now, so I may drop off.

Suppose "now", the present, is the principle which defines what is happening, the events which are occurring, presently. "Simultaneous" implies that numerous events, are occurring at the same time. The different events are necessarily at different places, if they are at the same time. Under the precepts of special relativity, depending on the frame of reference, the events which are occurring simultaneously, now at the present, vary. — Metaphysician Undercover

SR has no concept of 'now at the present'. You can add that to it, but it doesn't presume it, nor does it forbid it. In fact it makes no mention of it. I says that local physics works in all frames of reference, and that a preferred frame (not to be confused with the preferred moment) if it existed, would be locally undetectable.

Therefore the interpretation of now varies according to the frame of reference, such that we can have multiple presents.

No. If there is a present, there is probably only one of them, and a frame that does not correspond to it is simply not the preferred frame. Moments that appear simultaneous in the other frames are not really simultaneous.

I suppose there could be an interpretation with multiple presents, but I've not seen a name put to it. There is no logic that forbids it. One simply has to not refer to 'the present' and instead refer to 'this present and that other present'.

There is no interpretation of special relativity which renders "one present", because it makes no reference to said present because this implies a preferred frame of reference, which is strictly excluded by special relativity.

No, it doesn't exclude a preferred frame. It just says you can't do a local experiment to detect it, if there is one. Physics works in all of them (principle of relativity) and SR just extended that principle to electromagnetism. GR also says the preferred frame is undetectable. There is a unique frame which has the property of local isomorphism, but there is no way to demonstrate that if there is a preferred local inertial frame, it is that frame, especially since the frame is different everywhere.

Special relativity specifically disallows a preferred frame of reference, that is the fundamental principle of "relativity". So any interpretation of time which uses such a preferred foliation is inconsistent with special relativity..

Sounds to me like you're attempting to disprove the presentism I know you to hold, while I am defending it despite thinking it wrong.

As I understand special relativity, it is stipulated that simultaneity is dependent on the frame of reference. There appears to be two approaches to this assertion. One is that there are multiple presents, depending on frame of reference, the other that there is no such thing as the present. So I do not see how you can make special relativity consistent with presentism. — Metaphysician Undercover

Yes, multiple approaches (I count three), or interpretations of time, but they are no presents, or one present. No view has multiple presents.

One is 4D spacetime (no present), and the latter is 3D space that changes in time. Eternal vs Present view. They both work, but the present view demands a preferred foliation (which typically corresponds to an inertial frame only locally) and only one frame, coupled with a current event, defines local events that currently exist. The spacetime view says all events exist equally, and is pretty much how Minkowski and Einstein envisioned things.

The third interpretation is 4D with preferred foliation, but no preferred current moment. This corresponds to something like Lorentz Ether theory (LET). That interpretation, lacking an assertion of a 'now', also is grouped under eternalism, but there is an LET interpretation that posits in addition a preferred present, at which point the view becomes straight presentism.

Point 6 asserts that time clearly passes. I'd argue this is true for both Presentism and Eternalism: — Devans99

Umm... No. There is nothing that 'passes' under eternalism. Maybe you should read up on it,

There is clearly some distinction between present, past and future, because we can tell the difference.

Thus asserts the presentists, and you seem to be one, despite all your 'nails'. I would say that there is no moment that holds a distinction as 'present', and the existence of a present moment is in no way empirically distinct from the lack of it, so not at all clear.

So the world must be Presentist or it must be a flavour of Eternalism where there is some sort of 'now' cursor(s) that allow us to recognise the present. So either way, time passes. — Devans99

There is no flavor of eternalism that recognizes a 'now'. The lack of it is the primary premise. There are only temporal relationships between some pairs of events.

I think your mistake is that you intend to argue against an infinite past, and you mistakenly associate 'presentism' with the view.

2. Has 'now' existed always?
3. No. Implies a start of time. — Devans99

Begging. You're just asserting your conclusion here.

4. Implies time was created.

Logical contradiction. For it to be created, it must not have existed at some point, and later it existed. There is no 'and later' if time is not already there. Creation is a temporal verb.

6. Implies Presentism does not hold

Presentism doesn't assert that the preferred moment was started at some time in the finite past or was always there. It just asserts that it is currently this moment. As I said, you are clearly a presentist arguing against an infinite past, which is a valid position. But you need to find different labels for your views.

1. What exactly is an eternal being? — Devans99

I consider myself to be an eternal being: From the non-presentist viewpoint (the one your title claims to be arguing for), I didn't start to exist, nor will I cease to exist. And yet I have a birthday and count a finite number of seconds from that moment until the moment I make this post.

- Presentism it means the past and future don't exist, only now. — Devans99

Yes, but only two of your 'nails' (5 & 6) talk about that, and one of them argues for it, not against it.

- Has 'now' existed always?

Both presentists and eternalists might give different answers to this question. It is a different topic. You seem primarily concerned with arguing against an infinite past. Talk to the cosmologists. They have theories on both sides of that fence.

- No. Implies a start of time. Implies time is real. Implies Presentism does not hold.
- Yes. Implies an infinite past.

Time is real either way, whether it flows or is a dimension, or whether it is finite or infinite.
If it flows, it will probably stop. There is no forward flow of time given heat death, so it was probably thermodynamically bounded at the other end as well.

If you have a fault with my logic, please tell me what rather than just saying I'm wrong.

You haven't presented much logic. There is a series of what seem like begging assertions, and I question the assertions, not the logic that connects them. I don't personally hold to presentism, but I've never seen a falsification test for it. I've seen them proposed, but you're not attempting even that.

OK, yazata pointed out the same thing. Your reply:

The existence of only the present means time did not have a start, which means that things have been around eternally. Hence some of my arguments. — Devans99

No, presentism does not assert a lack of start to time. Maybe it started with the big bang, or maybe it was created by the prime mover.

The posts by Dfpolis point out most of the misconceptions you hold with presentism, and lack of awareness of its alternaitive eternalism which simply states that there is no present moment.

I've not read all the replies, but wanted to comment on my first impression of the OP:

1. What exactly is an eternal being? He has no start in time (no birthday so does not exist). Ask him how he came about. He cannot tell you. So he can’t exist. Because eternal is impossible

2. Say you meet an Eternal being in your Eternal universe and you notice he is counting. You ask and he says ‘I’ve always been counting’. What number is he on?

3. Take any physical system with a clock/timer. Make the system Eternal. What does the clock read?

4. Assume time is eternal. If it can happen it will happen. An infinite number of times. No matter how unlikely it was in the first place! So all things happen an infinite number of times. So all things are equally likely. Reductio ad absurdum. Time is not eternal

7. The universe follows rules that are described by mathematics. Negative infinity does not exist mathematically; there is no number X such that X< all other numbers because X-1<X. Hence the universe is not Eternal

8. If the universe has been around for ever then it should be in thermodynamic equilibrium by now. But the universe is not in thermodynamic equilibrium so time had a start — Devans99

Do you know what presentism is??? These six points all seem to argue against an infinite past, which is not something asserted by presentism. They also seem to be variations of the same nail, so to speak, but nevertheless a nail in a different coffin.
I find none of them valid. Mathematics supports an infinite past, just like it supports an infinite set of integers in both directions.

5. Relativity suggests the existence of multiple presents, whereas Presentism demands one present

Suggests, yes, but not asserts. It works either way. This point is actually about presentism.

6. Time clearly passes. Time cannot have started passing infinity long ago because there is no way to get to today (IE -oo +1 = -oo)

This one seems to argue for presentism.

9. Presentism is just so depressing why would anyone want to believe in it anyway?

The majority find the alternative more depressing.

So do you think that the preferred moment should be equated with the set of moments picked out by the CMB? It seems like one moment you think that it should (like in your previous response to me), then the next you think it shouldn't (like you are here). — Mr Bee

I am totally in the dark as to how the CMB would pick out a specific moment.

Since there is no difference between the CMB frame and any other in that sense, then that should give us reason to not take the former to represent the preferred moment that the A-theorists want.

How does a selection of a frame suggest there being a special moment in it? The block model has a objective frame, independently discoverable by observers elsewhere, but no preferred moment is similarly discoverable by other observers.

At least, this is part of the reason why I feel hesitant to call the CMB frame anything more than one that has some interesting properties.

Yes, that's why I called it an objective foliation, not necessarily a preferred one. By objective, I just mean it can be independently discovered by any observer anywhere. I don't mean a foliation that orders events in actual order. That would perhaps be that preferred frame.

It would be a different matter if that wasn't the case though. If the laws of physics do single out a particular foliation of events then it seems to be more of a stretch to deny that the present moment picked out by such a foliation is not the same as that of the metaphysical present, at least in my opinion.

I don't see how any foliation picks out any particular moment. It is a thing you've arbitrarily decided to add.

I suppose I don't find anything wrong with an infinite past, or infinities in general really, but I don't want to argue that here. There's also the possibility of cyclical time as well, if one doesn't want a first cause or an infinite past

Mathematically, I have little problem with either. Have to explain entropy though.

I feel like you're being obtuse at this point. I see no ambiguity in the use of "time-ordered". It means that causes always precede their effects in time. The author has been pretty clear in referring to time-order in that sense. — Mr Bee

That's why I wonder about before-before, which blatantly puts cause well after effect, and in any reference frame. Or at least it does in non-local interpretations.

they assume that each event has a cause preceding it in time, they actually dispose of the freedom of the experimenter

This seems to explain it. If measurements are taken yesterday, and Victor's decision as to how those measurements correlate not yet made, apparently the interpretation is that the results of the measurements cause Victor to decide to correlate them, despite complete separation (no causal path) from measurements made by Alice and Bob to Victor making his decision.

It apparently satisfies time-orderedness by switching labels of cause and effect.

As far as I can tell, the CMB frame is not a physically distinguished frame in the sense that a preferred frame in SR is physically distinguished (as in the laws of physics are observed to be different in that frame). In that sense, so much as it is preferred, such a fact would be undetectable.

Agree

It solves the problem of truthmakers for the past. In saying that the past exists and is real, the Growing Block Theorist has the resources to talk about it unlike the Presentist.

OK, that makes some sense. If the past is gone, is "Einstein existed" a true statement? Being a past tense, I don't see why not. It definitely changes the truth value of "Einstein exists".

Sorry, I thought you were just referring to QM interpretations

No, none of those seem to depend on any particular interpretation of time. I might be wrong about that.

In that case, the alternative interpretations to the Minkowski Spacetime such as the Neo-Lorentz interpretation of SR do include a flow of time as it is supposed to preserve the traditional view of time as a dynamic succession of events in a 3D universe.

It has that. Is this something different than Lorentz Ether Theory, because I found no mention of flow in any description of it. Maybe Neo-Lorentz adds that on top of LET. Lorentz himself seemed not to see things that way, especially since he set a lot of the groundwork for Minkowski's model.
Lorentz's model is older than knowledge of the expanding universe, so I wonder how he posited his preferred frame or foliation.

It's not really the A-theorists who are making that claim, but the B-theorists who are objecting to the CMB as a means of defining a preferred moment because it appears to be arbitrary to do so.

How could CMB possibly suggest a preferred moment??? A preferred frame, sure, but not preferred moment. The A-Theorists similarly do not base their definition of the preferred moment on the CMB. Their moment is simply 'now'. Easy-peasy.

According to them there is no clear link between the CMB and the preferred moment in metaphysics that should lead us to equate one with the other. In a sense, I can see where they're coming from, as noted above, the CMB is not physically distinguished like we would want it to be. In that regard, we have just as much reason to prefer it over any other alternative foliation of events.

Of course, if the CMB were to be physically distinguished and people are making the same objections then that'd be another story altogether, for one could very well have made such an argument prior to relativity in the 1800s with respect to the absolute time of Newtonian physics. At that point it would be unreasonable to require that there needs to be a neon light sign that says "This is a preferred moment of metaphysics" over the preferred moment picked out by physics in order to say that they are both equivalent.

I do not understand these paragraphs. I think you meant to say preferred frame.
What is 'physically distinguished'?

This is confusing to me. Becoming conceptually requires no uncaused causation, and even I see nothing contradictory about an uncaused cause.

Maybe I don't understand this notion of becoming. It's not a term I use regularly.
All causes seem to be effects of prior causes, but barring an infinite past, there must be a first cause, uncaused. Surely you've heard of that. Block theory has one, but it is just a (perhaps blank) initial condition. Not sure how becoming is expected to fit into that.

Again, the author refers to the preferred frame model of Bohmian Mechanics explicitly as one that is time ordered, and admits that it's empirical predictions are compatible with the correlations found in the before-before experiment. Take no offense, but at this point, I am more willing to side with his view over yours. — Mr Bee

A model is considered time ordered when it proposes that a cause event tomorrow can effect a measurement taken yesterday in the same place? Perhaps I don't know what 'time ordered' means, as used in that article. The one picture in there showed non-local influence arrow in a spooky-action setup, and without a preferred frame, the direction of the arrow would be ambiguous. So maybe that's what they mean by time-ordered: Not that the arrow always points forward, just that it doesn't point either way. In the before-before, it doesn't point in an ambiguous direction. It is consistently pointing backwards.

There's also the moving spotlight view of time as well, which says that all events in the universe's history exist but that there is a dynamic spotlight that shines on the set of events that represents the present. This is what I have told you at my first reply.

Well, to be thorough then, there might also be the one where only present and future exists, but the past, being no longer useful, fades away. I think the Langoliers movie depicted something like this.
The spotlight people definitely need two kinds of time, else how did the future come to be if it hasn't happened yet? How long ago was it created? How far did that part get before the spotlight started? Strange questions like that...
For that matter, I don't understand what possible problem is solved by growing block as opposed to presentism. I looked up the wiki page, and it defined it, but went no further in pointing out a single benefit of it.

No interpretation says anything about the existence of the block universe either. None of them have any direct say on the matters of the metaphysics of time.

The Minkowski model is one specifically of a block scenario. It is a straight metaphysical interpretation of time, making no empirical predictions distinct from the flowing model. Einstein drew on the mathematics of this model and Lorentz's work in producing his theory of relativity. But yes, the theory of relativity does not itself assert those metaphysics. It just uses the mathematics of spacetime, and refers regularly to spacetime as a unified whole.

Yeah, the direct implication of Relativity's postulates is that if there were such a preferred frame, it would not be empirically detectable, which some have taken to be evidence of it's nonexistence.

Only SR says it is undetectable. GR does not, since it isn't just a local theory. There are non-local tests for an isomorphic foliation, which isn't an inertial frame, but seems to be the most viable candidate for some kind of preferred ordering of all events anywhere.

The CMB is taken by some to be a preferred foliation of the universe in a sense,

Careful with your wording. The CMB is not a foliation and, being light, is certainly not stationary relative to any frame, but a foliation is suggested by combining the local frames in which the CMB appears to be isomorphic. Hence my calling it the isomorphic foliation.

but it is debatable whether it is good enough for the A-theorist's purposes.

Really?? Do any of them suggest another, like the frame of the solar system perhaps? That would suit the purpose of some people that would seem to have a requirement for A-theory.

The concept of becoming seems required only for the flowing model, but doesn't fit well at all with the block model. That's a good deal of the appeal of the block model is it doesn't need to explain the becoming.

I would actually argue that, in rejecting the idea of becoming, the block model has more trouble accounting for why the universe appears to become in time (given its structure), and that this is a weakness of the view relative to its alternative.

It does? I wasn't there at the time. Couldn't say. Yes, the A-theorists might say that, but doing so begs a different view. I find becoming to be difficult to explain, with all the uncaused-cause contradictions.
The block guy, if he posits that the block IS, needs to explain how it is, but not how it came to be. A different question, but still not an easy one. Platonic realism sometimes is invoked. My relational preference doesn't presume that anything IS, just that it relates to something, so I need to posit what the universe stands in relation to.

The article very explicitly addresses the before-before experiment and clearly states that preferred frame models such as that of Bohmian mechanics do not violate time-ordering. You're free to disagree with that but that is what the article states. — Mr Bee

No frame, preferred or otherwise puts cause before effect in the Bohmian interpretation of before-before results. So I guess I don't understand where the article addresses that. The two events are separated time-like, so there is no ambiguity to their ordering that can be disambiguated with a preferred frame.

Presentism is not equal to the A-theory.

From what I read, A-theory includes growing block and presentism, which differ in the ontological status of past events, but both posit the flow of a preferred moment, so all my comments about presentism so far also can be applied to growing block. Perhaps you can explain the distinction if it is more than that.

I'm saying that no QM or relativistic interpretation seems to propose flowing time. I'm probably wrong, but I'm just unaware of one. Some assert a preferred frame, but that isn't flow.

A preferred frame/foliation allows us to define an absolute order of events, and in turn the preferred moment.[/quote]First of all, no inertial frame foliates all events, so it would have to be some non-inertial foliation like the obvious comoving one. Yes, it allows (seems necessary for) the preferred moment, but does not need one.

The reason why Relativity undermines the idea of a preferred moment is because it states that there is no way to choose one frame or foliation of events, and that therefore there isn't any preferred frame/foliation.

Relativity just says it isn't locally detectable. Non-locally, one does suggest itself, and GR very much acknowledges it. It is the foliation where spatial expansion is symmetric/isomorphic.

Now there appear to be some who dispute this, who claim that a concept of becoming can exist without a global now but for the most part I am just going off of the traditional opinion on the matter.

The concept of becoming seems required only for the flowing model, but doesn't fit well at all with the block model. That's a good deal of the appeal of the block model is it doesn't need to explain the becoming.