FlashForward: Can the Future Be Changed?

The ABC prime time sci-fi series FlashForward deals entertainingly with free will, fatalism, time and the future, even if the starting premise is a tad implausible: the whole world blacks out for 2 minutes 17 seconds, during which people see glimpses of their lives 6 months in the future. Question: will these “flashforwards” (some pleasant, some horrific) necessarily come to pass? Can we change the future? You can see the first 10 episodes online at ABC or Hulu, the second season starts up again March 18 according to ABC.

The producer David Goyer says, not too ambitiously: "That is sort of the bulk of what we'll be dealing with philosophically over the second half of the season. It's not determinism, and it's not free will. We never intended it was either/or. There is a philosophical model of the universe that combines them, and we do deal with that head-on in the second half of the season."

From the first season:

 

Newspaper headline following the suicide of someone who saw himself *alive* in his flashforward: “The Future Can Be Changed”.

 

Two physicists haggle over their responsibility for an experiment that might have caused the blackout:

 

Simon: Fate is fate, we’re not responsible, Lloyd.

Lloyd: What about free will?

Simon: No such thing.

Lloyd: Oh since when did you become such a hard determinist?

Simon: Simple quantum suicide theory. I will win this hand and every subsequent hand we play, ad infinitum, QED.…

Lloyd: You’ve upended the whole world and you hide behind determinist rhetoric.

 

Newscasters discussing the blackout: “Let’s get back to the big question: do we have free will… that’s the big question, possibly the central question of human existence for millennia” (fades out)

 

My take on the FlashForward problem set is here. I predict that because it must cater to folk libertarianism on free will and the metaphysical openness of the future, the show will give short shrift to the “block universe” view of things (accepted by many physicists as a consequence of special relativity), in which all events, past, present and future, are immutably fixed in spacetime. But of course the producers might falsify my prediction. Stay tuned!

Comments

[Bryan White]

I'd agree that all events, including future events, are fixed in space-time, but fail to see how that does damage to libertarian free will by itself.
These sci-fi time travel scenarios tend to bug me. A character will experience the future, then go back in time in an effort to avert that future. If that future was averted, then what was the time-traveling character experiencing?
It is try via tautology that what will happen in the future will happen in the future. I don't see such logical determinism as a problem for libertarian views of the will.

[R. Clarke]

What fills out the inference from: the future is, to: the future is fixed?

[Bryan White]

The principle of identity. That which is, is. If it were different then it would be something else (iow, once we allow that A can be ~A at the same time and the same sense we may have cut loose from any possibility of making sense of things).
Some folks use "the future is fixed" specifically to mean that options are limited, and it may be implicitly understood that they are causally limited. That inference is worth rooting out, for it seems to represent the inference that would make things difficult for libertarian free will.

[Bob Doyle]

Randy,

I would like to back up your chain of inferences.

"The future is" is itself already making an untenable claim. The proper statement is "The future will be."

"The future is" appears to me to assume the conclusion in the premise, don't you think?

Tom,

The "block universe" is not "accepted by many physicists," though virtually all physicists accept the special theory of relativity.

Mathematical physicists, notably Hermann Minkowski in 1907, envisage a space-time diagram in which time is a fourth dimension already "in existence" in some (multiple dimensions) sense.

This fits comfortably with a "God's eye" view in which all times are present to God.

It is also similar to the modal thinking of David Lewis in which any imaginable alternate universe consistent with logic also exists - as do all times in those "many worlds."

The normal interpretation of special relativity distinguishes "space-like" from "time-like" separations and describes events that have causal relations as in the "light-cone" of events in our future (or past).

Block-universe thinking denies there are things we can cause (or be caused by). In a classical mechanical deterministic universe all motions are "reversible."

Newton's laws of motion are same when time goes backwards.

Causality simply disappears. Every event is already caused by something "outsisd space and time."

This view is accepted by many philosophers of science - Michael Lockwood, J.M.E. McTaggart and J.J.C.Smart come to mind.

Smart calls the view "tenseless" because past, present, and future are all the same in the block universe. It is also known as Eternalism.

In 1966, C.W.Riedtijk published "A Rigorous Proof of Determinism Derived from the Special Theory of Relativity."

The most famous philosopher to discuss this case is Hilary Putnam (1967), the most famous physicist is Roger Penrose (1989).

Just last month, the experimental physicist Nicolas Gisin proposed the special relativistic paradoxes of simultaneity as related to the puzzles involved in the Einstein-Podolsky-Rosen Paradox (Bell's Theorem and all that).

References are below, for those who want a deeper understanding of the science (fiction) behind FlashForward.
___________________

Rietdijk, C.W. (1966) A Rigorous Proof of Determinism Derived from the Special Theory of Relativity, Philosophy of Science, 33 (1966) pp. 341-344

Putnam, H. (1967). Time and Physical Geometry, Journal of Philosophy, 64, (1967) pp.240-247

Being and Becoming in Modern Physics. Stanford Encyclopedia of Philosophy.

Penrose, R. 1989. The Emperor's New Mind: Concerning Computers, Minds, and Laws of Physics. New York and Oxford: Oxford University Press, pp.191-201.

Grünbaum, A 1963. Philosophical Problems of Space and Time, Knopf

Lockwood, M. The Labyrinth of Time, Oxford, 2005, pp.56-61

Gisin, Nicolas, Science, 326, 4 December 2009, pp.1357-8

[Tom Clark]

Thanks Bob. So there seems to be no consensus on this among physicists. Over at Cosmic Variance, Sean Carroll is discussing his book on time and says regarding chapter 1: "The most important non-obvious stance I take in this chapter is to come down firmly on the side of an “eternalist” or “block universe” conception of time. The past, present, and future are equally real. Philosophers and other deep thinkers have been arguing about this for years, and I kind of dismiss the whole discussion in a couple of paragraphs. Sorry, philosophers! It’s an important issue, but we have other conceptual fish to fry."

Physicists Brian Greene in The Fabric of the Cosmos and Vesselin Petkov at Concordia University also take the eternalist position. But you're saying they're all wet.

I'm wondering if the disagreement is on the actual physics or on its philosophical interpretation when it comes to tricky concepts like time which have both commonsensical and technical meanings. I'll stay tuned, and thanks for the references.

[R. Clarke]

Let's say that it's fixed that P just in case P and it isn't up to anyone whether P.

(In discussions of the consequence argument, the fixity of the past and the laws comes to roughly this.)

How does the existence of the future imply its fixity?

Suppose that 'P' states some fact about the future.

Distinguish:

1. It can't be that (P and someone will bring it about that not-P).

2. P and no one can bring it about that not-P.

The fixity of the future fact that P is more than 1; it's something in the neighborhood of 2. What does the existence of the future add to the fact that P to give us an entailment of 2?

'P' tells us that no one will bring it about that not-P; it doesn't tell us that no one can. How does the existence of the future tell us any more than this?

[Bob Doyle]

Tom,

I guess there are a number of great thinkers and writers who are "all wet" in my opinion on the block universe and eternalism.

Some who come to mind besides those I mentioned are the members of the "New York Group" like David Alpert ("Time and Chance,", Quantum Mechanics and Experience"), Barry Loewer (who posts to the Garden occasionally), and Brian Greene.

Sean Carroll discussed determinism and the block universe with David Alpert on Bloggingheads.

Randy,

Your idea that statements about the future can imply its fixity is the ancient Master Argument for determinism of Diodorus Cronus. Aristotle's famously discussed it as the truth value of statements about a future "sea battle."

Diodorus argued from an assumed necessity of past truths (which is understandable, if a misapplication of logic to physical reality) that something is impossible that neither is or ever will be true.

Aristotle reframed the argument as the truth or falsity of the statement that a sea battle will occur tomorrow. Despite the law of the excluded middle, which allows no third case, Aristotle concluded that the statement is neither true nor false, supporting an ambiguous future (which William James made the core of his two-stage argument for free will).

Here is the Aristotle

"What is, necessarily is, when it is; and what is not, necessarily is not, when it is not. But not everything that is, necessarily is; and not everything that is not, necessarily is not. For to say that everything that is, is of necessity, when it is, is not the same as saying unconditionally that it is of necessity. Similarly with what is not. And the same account holds for contradictories: everything necessarily is or is not, and will be or will not be; but one cannot divide and say that one or the other is necessary.

"I mean, for example: it is necessary for there to be or not to be a sea-battle tomorrow; but it is not necessary for a sea-battle to take place tomorrow, nor for one not to take place — though it is necessary for one to take place or not to take place. So, since statements are true according to how the actual things are, it is clear that wherever these are such as to allow of contraries as chance has it, the same necessarily holds for the contradictories also. This happens with things that are not always so or are not always not so. With these it is necessary for one or the other of the contradictories to be true or false — not, however, this one or that one, but as chance has it; or for one to be true rather than the other, yet not already true or false."
(De Interpretatione, IX, 19a23-39 ) 6

Aristotle never denied the law of the excluded middle, merely that the truth or falsity of statements about future events does not exist yet. Note that this implies at least some things in the past may be changed in the future, in particular, the truth values of statements about the future.

[Tom Clark]

Bob,

Sean Carroll opines at Cosmic Variance that "I think most physicists are block-universe believers, even if they never lay out that belief explicitly. That seems to be the most natural reading of the differential equations that we think govern fundamental physics."

This supports my hypothesis that the disagreement is about the picture of reality one derives from generally accepted equations. It's interesting that there's that much interpretive space left open by the equations to permit such different conceptions of what reality is really like. Ideally there would be some way to test between the conceptions so that this disagreement could be settled. If there's no way to test, then the conceptions aren't falsifiable and thus simply speculations. Sean's criterion is the "naturalness" of his reading of the equations, but no doubt you and other presentists would contest that claim.

[John Fischer]

Patrick Todd has a really interesting new paper coming out in Oxford Studies in Philosophy of Religion, "Geachianism". In this paper Patrick explores some ideas that were suggested by Geach to the effect that the future in a given possible world changes over time. So, for example, it was literally true at some point in time that Hilary Clinton was going to win the Democratic nomination for President, and later it was false that she would win the nomination, and so forth. Patrick also applies this idea to issues arising from the Pike-style argument for the incompatibility of God's foreknowledge and human freedom.

It is a really fascinating article, and it explores the notion that we can change the future in a very strong sense. Highly recommended! You can find this paper via Patrick's website: http://sites.google.com/site/patctodd/home

[Tom Clark]

Thanks John, will check this out. I'd love to know what sources FlashForward producer David Goyer consulted when putting together his "philosophical model of the universe" that combines free will and determinism. Any Gardeners fess up!

[Per Milam]

Another interesting piece on this topic is Steven Cahn's (1967) book, "Fate, Logic, and Time." Cahn's intent is to make an anti-fatalist argument contra, among others, Richard Taylor.

Ultimately, he, like Patrick Todd, relies on the claim that truth values for future events can change. Unlike Patrick and (perhaps) like Aristotle, however, he argues via a 3-valued logic (with an 'undetermined' truth value). So, for Cahn, the truth value changes are from undetermined to either true or false, not from true to false or vise versa.

Cahn also thinks that allowing truth values to change requires allowing the modality of a statement to change. The modality of a statement whose truth value changes from undetermined to true when the event in question occurs changes from contingent to necessary (albeit to "past necessary"--the type of necessity that an event has in virtue of being past). This is something Patrick may have to accept as well since a change from true to false, or vise versa, when the event occurs presumably changes the modality of the statement from contingently true to necessarily false (again in the sense of "past necessity").

If one thinks that "past necessity" is a worthwhile notion and relevant to this type of debate, Cahn's position introduces some further implications of changing truth values to consider.

Another interesting article on this topic is Michael Rea's article on presentism and fatalism. There he argues that presentists must choose between bivalence and libertarianism, but cannot consistently accept both.

[John Fischer]

Per,

Thanks for this helpful post.
Also, I look forward to seeing you and all the UCSD folks Friday when I solve the luck problem for libertarianism...

[KT]

That's very kind of you to do so, John.

[John Fischer]

Kevin,

In SD I'll be my Avatar, SemiLibertarian Man...

[Mark Young]

I'd like to make a comment on Todd's Geachianism paper -- my apologies if this is not an appropriate venue.

I agree that the floor does not prevent the workers from falling to their deaths -- they wouldn't be up there if the floor weren't there, and the continued existence of the floor surely can't count as an event.

On the other hand, the net does prevent the careless worker from falling to his death. The worker could have been up there and carelessly fallen even if the net had not been there. Putting the net up was an event, and it prevented this worker's death.

Yet the net does not prevent the jumping worker from falling to her death. She would not have jumped if the net had not been there to catch her.

It seems to me that what is prevented is not what was going to happen so much as what would have happened. If the floor had not been there, there would not have been any workers there to fall to their deaths; if the net had not been there, the one worker would not have jumped, but the other would surely have fallen to his death. And what would have happened can be modeled using possible worlds -- the nearest possible worlds in which the net had not been placed are worlds where the one worker does not jump and the other worker falls to his death.

The question of whether we can change the future is, I think, an issue of terminological convenience. Did placing the net "change the future"? Well, where we are now is different from where we would have been, but that only means the future was changed if where we would have been was the future before the net was placed. Was it? Does it matter? I don't see why. It seems to me to be of a piece with the question of whether a motion at a joint US-UK meeting was tabled or not. What we want to know is -- is the motion going forward? What we want to know is -- what should we do?

As for the omniscient god, the proper (IMO) view is that the very concept requires acceptance of backwards-in-time causality -- that the god believes (at t1) that Jones will do X at t2 is not causing Jones to do X at t2; rather Jones doing X at t2 is causing the god to believe (at t1) that Jones will do X at t2. Whether Jones doing X at t2 is caused by the state of the universe at t1 is an orthogonal issue, as is the question of wehether Jones is morally responsible for doing X at t2.

[Paul Torek]

Getting back to the block universe, if I might... Has anyone else noticed that it is possible to have an Eternalist view of time without accepting determinism? And that at least one highly plausible interpretation of modern physics does exactly that?

I'm thinking of the Transactional Interpretation (TI) of quantum mechanics. powerpoint format html format

To summarize some (not all) crucial features, TI involves offer waves and confirmation waves, which if they interact so as to conserve relevant quantities, form a transaction. The transaction is the familiar physical event that all interpretations agree on, such as the transfer of energy via a photon of light from a source to an absorber. The offer waves go forward in time and carry positive energy. The acceptance waves go backward (!) and carry negative energy. In the photon emission-absorption example, the waves cancel out everywhere except in the spatiotemporal region between emission and absorption. A similar cancellation would apply to other examples.

Ruth Kastner discusses applications to some experimental results, along with some philosophical niceties, here. A juicy bit:
"TI continues to provide an elegant and natural account of quantum phenomena, provided that we consider offer and confirmation waves as residing in a 'higher' physical space corresponding to the configuration space of all particles involved. This space can be considered as a physically real space of possibilities; thus 'real' is not equivalent to 'actual.'7 7 Thus this proposal can be characterized as a version of possibilist realism constrained by specific physical law."

Two more things to note about the TI:
1. The future is every bit as real as the past. The transaction makes no sense otherwise.
2. It's indeterministic. The past alone is insufficient, in combination with natural laws, to define the present. You need to throw in the future as well.

Questions to Gardeners: Does point 1 make the TI universe a "block universe"? If so, is that a problem? Is it a bigger (or more fundamental) problem than determinism?

[Ruth Kastner]

Thanks for your question. No, I don't think TI necessitates a block universe, at least in its "possibilist" form. In this form, all aspects of time are secondary, supervening on possibilities (offer and confirmation waves) and their transactions. In a sense, you could say that spacetime is 'created' by way of transactions.
RK

[Ruth Kastner]

BTW, check out my latest preprint on TI:

http://arxiv.org/abs/1001.2867

which argues that TI does a better job than "many-worlds" interpretations at solving quantum perplexities.
Questions/comments welcome.
RK

[Paul Torek]

Ruth,

Thanks for replying. Unfortunately, my home computer is too ancient to read your PDF at arxiv.org. I'll read it elsewhere at the first opportunity. Maybe that will clear all my confusions, but I'll ask some questions now, anyway.

If "aspects of time are secondary", does this mean that events such as photon emission and absorption are secondary, and that objects such as the emitter and absorber are secondary, as well? Is it necessary to regard them as secondary? Would it be possible - maybe even advantageous - to regard them as co-equals instead, with the quantum formalism describing their mutual fit?

Correct me if I'm wrong in the following. When explaining the Quantum Liar Experiment, or any other experiment, generous helpings of facts about the past and future are used. For example, equations are constructed based on the fact that if the photon travels a certain path, it will be reflected, or absorbed, or what have you. This presumes the presence of the mirror, or absorber, or (etc). So, it seems to me, the panoply of offer and confirmation waves is constrained by the existence of these mirrors and absorbers and so on. But, the existence of these mirrors and absorbers also can be related to events in their futures and pasts. As David Bohm might say, there seems to be a lot of wholeness and implicate order going on here. Rather than putting possiblities at the top of some metaphysical pecking order with events and objects in spacetime below them, they seem both to stand in a relationship of mutual constraint or mutual fit.

But, if there is this wholeness and implicate order, does that not make a "Block Universe"? Of course, I understand that the phrase was coined in reference to an interpretation of relativistic physics, not QM. And perhaps (I'm frankly ignorant here) that was a specifically deterministic vision. But, must "Block Universe" be defined as deterministic? Doesn't the point of that phrase lie elsewhere? The questions in this paragraph are aimed at Tom Clark at least as much as at Ruth, or anyone else who finds the Block Universe issues interesting.

[Ruth Kastner]

In my Possibilist TI account ("PTI"), photon emission corresponds to an offer wave (OW) which is a possibility, not an actuality. Absorption is accompanied by a confirmation wave (CW) which is also a possibility, not an actuality. In PTI, spacetime designations only exist for transactions. So "spacetime" does not exist separately from completed transactions. Yes, the set of OW and CW must all "fit together" and this is what the quantum formalism describes, via the Hilbert space structure and accompanying dynamics. So there is a lot of stuff going on that has to be coordinated according to physical law, but most of it is on the level of unactualized possibilities. Talking about an absorption event as "in the future" of an emission event is only retroactive talk, from the vantage point of what we would experience as a result of a completed transaction involving that emitter and absorber. From the point of view of OW and CW, there is no passage of time --these are atemporal processes (as Douglas Adams said, "Time is an illusion; lunchtime doubly so.") Note that emitters and
absorbers can also just be OW: e.g., an electron OW could serve as the emission point for a photon OW. Emitters and absorbers in experiments are usually taken to be macroscopic objects (which is just to say that they are actualized events by way of very probable and nearly continual transactions). But in principle, you don't need an "actualized object" of this kind to serve as an emitter or absorber.

For those who view spacetime as a substance, no doubt this all sounds very strange. See Harvey Brown's _Physical Relativity_ for a non-substantival (relational) account of spacetime that is harmonious with PTI. Recall that we don't experience spacetime; we can't observe spacetime; all we can observe are events (transactions). These can be ordered by reference to spacetime paramaters, which really just refer to our experiences of them and their relationships as actualized events; spacetime parameters need not refer to an independently existing substance.

[Tom Clark]

Paul asks

"But, must "Block Universe" be defined as deterministic?"

In footnote 5 of "Scripting the future" I say

Quantum randomness or indeterminacy doesn’t upset the block universe view. As J. J. C. Smart puts it in his book, Our Place in the Universe: “The whole universe is determinate. This is so whether it is deterministic (as used to be believed) or is indeterministic (as is at present believed. The determinateness of future events does not imply determinism. An event can be just as determinate whether its occurrence does or does not depend on the laws of nature together with some earlier state of the universe” (p.155, quoted at the Information Philosopher website).

[Ruth Kastner]

There is one big problem with Smart's argument. He misrepresents the relationship of quantum indeterminacy to the truth values of propositions. He briefly refers to a two-slit experiment, then switches to talk about position vs momentum: "'The electron has a definite position' and 'The electron has a definite momentum' are false. Thus the indefiniteness in quantum mechanics does not imply indeterminateness or absence of truth value of propositions, or a third truth value different from 'true' and 'false'. (p.154-5)"

But in fact there *are* propositions for which there is no determinate truth value: e.g., "The particle went through slit 1". This statement is neither true nor false. Smart just happened to pick a kind of statement, regarding quantum system in a superposition like this, that has a truth value. In general, however, quantum indeterminacy does result in lack of determinate truth values for propositions that, classically, would always have determinate truth values.

Thus Smart's claim that the universe is determinate--apparently based on the alleged availability of true/false truth values for propositions applying to quantum systems, does not hold up--since there certainly are quantum propositions with no determinate truth value. Smart "stacks the deck" in his argument by serendipitously selecting one of the few types of propositions that does have determinate truth value in qm cases: i.e., propositions about whether there is a definite property or not. This is a special type of proposition that plays a prominent role in the "bare theory" version of Everett (see, e.g., David Albert's _Quantum mechanics and Experience_.

[Paul Torek]

All,

Can we come up with a working definition of "Block Universe"? How's this: Block Universe (class A) = Eternalism + bivalence about (class A of) propositions about the future. The interesting class might be, for example, human actions. Thus we might care, in certain contexts, about a fact of whether Paul Torek goes through door 1 or door 2, but not about whether an electron goes through slit 1 or slit 2.

Here are five regions along a spectrum of where TI (or PTI) lands us w.r.t. Block Universes for human Action (BUA):
1. If TI then definitely not BUA
2. If TI then it's hard to suppose BUA
3. Makes no difference
4. If TI then it's hard not to suppose BUA
5. If TI then definitely BUA

I'm thinking something like 4. "Time is an illusion" looks very BU- (and BUA-)friendly, while "spacetime is not a substance" seems not to tip the balance either way.

Alternate suggestions welcome.

[Ruth Kastner]

Oh dear! Definitely not 4 or 5. The term "block universe" means that the future is predetermined (i.e., all events are "there" in the future--and in the past, for that matter). "Time is an illusion" is meant to convey that time appears only at the level of completed transactions, a result of all the relevant possibilities having weighed in. As physical systems, humans are rooted in those possibilities at a fundamental level. 'Paul Torek going through a door' takes place based on a high number of very probable transactions.

The "block universe" view is fundamentally incompatible with PTI, because it tacitly assumes that spacetime exists as a primary substance. PTI takes the opposite view: the primary substances are OW and CW, and 'spacetime' is just a name for the ordered pattern of transactions arising out of those possibilities.

[R. Clarke]

Here is one way--I think a fairly standard way--of understanding what it is for some event E to be predetermined: there are some prior events and some laws, such that it isn't possible for there to be those prior events and those laws and E not occur.

With predetermination so understood, what is it about a block universe that means that the future is predetermined?

It is then doesn't imply that it is predetermined to be then.

[Paul Torek]

That was my understanding of "predetermined" too.

Should "spacetime is substantive" be added to the definition of Block Universe? That would make historical sense, I guess. Maybe I should just call Eternalism + future facts, exactly that, Eternalism + future facts (EFF for short).

But I'm thinking that in that case, for the purposes of the Garden, EFF is what's interesting about BU.