Readers' Choice: Cheating the Causal Game

Thomas Ray

John,

I think Paul Davies is the best plain-language source to explain how physics treats time. The deep nature of time is still an open problem.

Best,

Tom

John Merryman

Tom,

If time is an open problem, then why are you so resistant to considering my observation that by primarily treating it as a measure of duration, physics only assumes and re-enforces the individual perception of a sequence from prior to succeeding events/past to future, rather than explore how these configurations come into being and are replaced/future becoming past, other than that I'm far less of a member of the club than you?

I realize it seems like an extremely trivial point, but that doesn't mean it and its consequences can't have been overlooked. If I throw a ball up in the air, knowing only the direction and momentum, where it lands can be fairly accurately predicted, but that doesn't have to mean the arc of its trajectory is somehow permanently etched in some eternal geometric configuration.

Regards,

John M

John Merryman

Considering that if I first spin around and then close my eyes before throwing it, the trajectory, according to QM, exists in some super position of all possible trajectories. ;-)

Thomas Ray

John,

It's interesting to me that you would associate your way of thinking with head bangs. I was already 60 years old before I found out that my dyslexia is probably the result of a traumatic automobile accident when I was three years old. Of the occupants of our vehicle -- my stepfather, mother, infant child and me -- all were seriously injured (baby killed) except I, who was thrown from the car and apparently suffered only a gash at the back of my head, which was closed in the emergency room with sutures. It was a hard blow, though, because I remember losing consciousness and recovering while rolling down the grassy highway embankment.

Up until that few years ago, I had no idea that dyslexia can be caused by head injury in childhood. The site of my injury, though, exactly corresponds to the right brain tasks that I have always had difficulty with, though less extreme as I have gotten older.

Off topic, so I'll keep it short.

Tom

Thomas Ray

" ... that doesn't have to mean the arc of its trajectory is somehow permanently etched in some eternal geometric configuration."

How do you know that?

Tom

John Merryman

Tom,

It ties into information theory. If the same information can be recorded on any medium, say a song on a vinyl record, cassette tape, or cd, then logically the same medium can be used to record different information. The vinyl repressed, the cassette or cd rerecorded.

The question is whether they can store different information at the same time. That does depend on how you define both the information and how it is accessed. Such as a holograph, where different angles form different images, but that is as much a function of how the information is perceived, as how it is recorded.

Now say the medium is me throwing a ball up in the air. Effectively the information of it leaving my hand is recorded over by it flying through the air, as that is recorded over by it hitting the ground, since the medium is the ball and it can only manifest one position, since it is only one ball. So in order to progress from one configuration to another, the prior must cease to exist.

Now like the holograph, different perspectives can yield different information. Say you are several hundred thousand miles away, with a very good telescope, watching me throw that ball. Given the finite speed of light, you will be seeing it leaving my hand, at about the same time as I'm watching it fly through the air. Yet just as I only see it at one position at a time, so do you, even though it is delayed by consequence of your more distant perspective. This does not mean the ball exists in some super-position, or is eternally extended along this trajectory, only that information is both a function of transmission and reception.

Otherwise I don't see any realistic physical explanation for how it can actually exist all along some time vector. If you have some explanation that sounds reasonable, I'm all ears, but just putting the math up on a pedestal and insisting it explains all, without showing how, doesn't count.

Regards,

John M

Thomas Ray

John,

"The vinyl repressed, the cassette or cd rerecorded."

Right. That doesn't mean the prior information is destroyed, though. Do you know how your computer hard drive memory works? -- overwriting with new information doesn't make the previous information disappear; it's just jumbled up and can be recovered by another algorithm. Now maybe you want to say that smashing the hard drive renders the information unrecoverable; however, that begs the question. In principle, software can run on any substrate, so whatever nature records is recoverable in principle -- that's what Hawking's solution to the black hole information paradox is all about.

"So in order to progress from one configuration to another, the prior must cease to exist."

To reemphasize: that's begging the question.

Best,

Tom

John Merryman

Tom,

As well as the trajectory of the ball can deduced from where it landed. The question isn't whether evidence of the past ceases to exist, but if the events of which the past consisted have been replaced by the fact the physical reality is now manifesting this present configuration. There is certainly lots of evidence of past events, but the very fact these traces do exist in the present means they are no longer as originally produced. Those layers and layers of historical evidence are proof time is a dynamic process, in which that evidence and memories continue to be altered, effectively pushing the events further into the past.

Regards,

John M

[deleted]

It seems plausible to me that time is actually an emergent property, something we observe as a result of causal relationships. The trick is to think of casual relationships outside of a chronological ordering.

Imagine a universe that is vast but finite - both in terms of the smallest distance and in terms of the largest distance. Given that, it is possible to write down a diagram that represents a snapshot of all possible states of the universe as a big graph: each state is a node and the causal relationships between the states are edges.

There is no way to tell if two events that are not directly causally related to each other happen before or after each other. Nor is there any indication of how 'long' any state exists or how long it takes for one state to 'cause' another. It's just one big logical graph that shows the gigantic-but-finite web of relationships.

Given such a graph, if we make just two assumptions, I believe an arrow of time naturally emerges:

1. Every state must have at least one cause.

2. No state can participate in its own causation.

Setting aside the question of "where did the first state come from", it seems plausible to me that our perception of time is merely the way our minds interpret this web of causation. There is no 'before' or 'after', only causation.

It is tempting to think of two states that are directly causally related as having an ordering, but what if the 'caused' state has more than one 'causing' state? For example, if state C is caused by both state A and state B, perhaps we can infer that C occurs in some sense 'after' A and B. But can we infer that A and B are synchronous?

Anyway it is fun (at least for me) to think about, and it seems that causality is very deeply related to both time, and probably entropy as well. Could it be that both of those concepts are merely emergent phenomena from some deeper logical causal theory?

Eckard Blumschein

Yes Darrell, the order goes on to emerge,

I even blame anything around Hilbert's finitism including the notion state for what is called the crisis of physics. I was born because my mother A (Annemarie) met my father B (Blumschein). Were they events in the sense of a Hilbert space?

The question of "where did the first state come from" implies the assumption that there was a first state and in logical consequence there will be a last state. I consider such rather religious questions futile while the alternative idea of an open in the sense of infinitely extended and therefore never fully predictable world fits better to feasible science. Let's accept one boundary as relevant for physics, the border between past and future and nothing in between.

Instead of blindly trying to separate causality from temporal order, I recommend to clarify first that abstract time must not be confused with the measurable elapsed time of reality.

Eckard

John Merryman

Darrell,

The problem I keep pointing out is that we model time as the sequence of events we encounter/past to future, but the cause is changing of the state/future becoming past. For example, the earth is not traveling some fourth dimension from yesterday to tomorrow, but tomorrow becomes yesterday because the earth rotates.

Meanwhile cause is not due to temporal sequence, but exchange of energy. Yesterday doesn't cause today, nor does one wave cause the next. The sun shining on a rotating planet and wind across the water create these cycles of action.

Regards,

John M

Thomas Ray

" ... if the events of which the past consisted have been replaced by the fact the physical reality is now manifesting this present ..."

Still begging the question, John, any way you rephrase it.

You are assuming boundaries between what you call past, present and future that have no physical basis. The configuration space of events doesn't know the difference.

Tom

Eckard Blumschein

John M,

You wrote: "General Relativity refutes the notion of simultaneity." Hm, can a theory at all refute something? Any simultaneity is called a convention as to justify Einstein's misuse of Poincaré synchronization.

I understand that you and many others intend to arrange with the dominant acceptance of Einstein's theories. Are you consequently "forced to accept that all events exist in some "blocktime" vector?" I think so. In my previous essay I uttered the hope that Michelson's non-null expectation could be flawed. Having quantified the flaw as too minute, I admit, I was wrong. Please read the endnotes in my current essay.

Tom wrote: "The configuration space of events doesn't know the difference."

He is quite right, however, may we really equate reality and configuration space?

Regards,

Eckard

John Merryman

Tom,

I'm not assuming any boundaries more substantial than a horizon line. With time as an effect of action, how do you draw solid boundaries between where a moving object was, is and will be? Would you expect a measure of temperature, also another measure of action, to be infinitely precise?

The problem is the fourth dimensional model of time is trying to overcome the problems inherent in Newtonian time, but modeling the measure of duration as part of some foundational geometric structure creates serious problems as well.

Eckard,

I can try. Nothing more, nothing less.

Regards,

John M

John Merryman

Tom,

Speaking of horizons, consider the transition from one day to the next; Locally it is from 11:59:59 pm to 12:00 am, but globally it is 24 hours.

Time is fluid, so our conception of it needs to be as well.

Regards,

John

Thomas Ray

John,

As Eckard validates, if you don't deny relativity you have to accept what the theory says about time.

"I'm not assuming any boundaries more substantial than a horizon line."

When you stand on the Maryland shore facing East, does Europe not exist at the same moment you are looking in that direction? Does the horizon which Europe lies behind rotate to meet you, so that you pleasantly find yourself in Paris if you stand still long enough? Only in a different inertial system, high above the shore -- could such a phenomenon happen for you. And even at that, you would have to invest energy in keep your vehicle in the same spot.

"With time as an effect of action, how do you draw solid boundaries between where a moving object was, is and will be?"

*Physically*? I wouldn't draw such boundaries. Time isn't an effect of action; time and action are related by very specific mathematical quantities of distance and duration, which is why the Minkowski space is a good choice to model dynamical and kinematic systems of events. If we wish to extend relativity, we don't wave a magic wand and say that we are going to preserve relativity, but do away with distance and duration. That doesn't work -- and can't.

I think, as I've said before, that brain science is the next big frontier of physics research. It is here, in the discrete relations among neurons in a connected network, that the quantum measurement problem really matters.

"Would you expect a measure of temperature, also another measure of action, to be infinitely precise?"

Isn't that what WMAP and its predecessors are all about? John, the reason that your ideas of time and temperature are unrelated to anything physical is that you think of temperature as something physically real -- while it is only a measure of averaged particle motion within arbitrary boundaries. The WMAP results assume the boundaries at the big bang and the present state of the universe. So our measure of temperature is at least as good as the accuracy of our probes, though never without boundary conditions.

Best,

Tom

John Merryman

Tom,

You have it backward. My point is that I don't see time as "physically real." No Newtonian flow, no fourth dimension, no blocktime. It is just an effect of activity, ie, change, as temperature is a scalar measure of the energy effecting activity.

If I "stood still," would first go through San Francisco, then Tokyo, then Istanbul, before getting to Paris.

I don't see how accepting part of an argument means I have to accept every conclusion drawn from it. It would be a version of reductio ad absurdum.

Regards,

John M

[deleted]

John,

I am well aware of swimming in FQXi against the Lorentz/Einstein/Davies stream. The latter quoted Einstein: "Two events that occur at the same moment if observed from one reference frame may occur at different moments if viewed from another."

My endnote demands to simply restricting the consideration to just one frame of reference. Well, there is no preferred frame of reference. However, once the reference (in case of numbers the number one) has been chosen, it is not allowed to choose one more reference.

Perhaps you will spontaneously agree that something that happens at the Mars does not depend on how much delayed it is observed at different locations of the universe.

Unfortunately those like Hilbert (who intended to be more than a mathematician) and Davies (who misled you) think of time as laid out in its entirety. Accordingly, even engineers like me were forced to always perform FT by integrating over time from minus i to plus infinity. This is not reasonable.

Meanwhile I revealed decisive mistakes related to the denial of the distinction between past and future and the belonging history in mathematics and physics.

Eckard

[deleted]

Eckard,

You and I are in agreement that time is a(measure of a) dynamic process and not a static state. Unfortunately the physics community has invested generations believing otherwise.

Consider the whole Big Bang cosmology is built on this notion of spacetime, yet even I can see it makes no sense to say space expands, yet retain the constant speed of light as cosmic ruler. If space is what you measure with a ruler, is it what remains constant, or what expands?? They both can't be the denominator.

Tom,

I'm not doing away with distance and duration, only making the point they are apples and oranges. Distance is a measure of space, but duration is a measure of action. Action occurs in space, but creates duration. Just like it creates temperature. You could use ideal gas laws to correlate temperature and volume in a similar fashion. Constrain a quantity of energized gas to a smaller volume and it raises the temperature in a proportional manner, much like squeezing a balloon will cause it to puff out between your fingers, but would that make temperature some fourth parameter of volume? It's basically the same sort of logic being used to correlate distance to duration.

Regards,

John M

Eckard Blumschein

John M,

May I ask you how accurate the largest distances of stars were measured? I found at http;//christiananswers.net/q-eden/star-distances.html larger than 15 billion ly. While the error of parallax method (for small distances) is given as 10%, Cepheids are a category of stars whose actual brightness is allegedly "well known". Perhaps, the redshift method is even less certain. How accurate were the measurements when Hubble came up in 1923 with his expansion law?

My primary concern is the perhaps relativistically calculated Doppler effect. See my current discussion with Pentcho.

Eckard

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