Multiple Pasts Theory Pt. 2

[modelmark]

I think this is false because of the way you defined the rules. If your rule is 'two numbers add up' than you know that 1 and 3 result in 4, but going back in time from 4 you do not know if it came from 2+2, 1+3,3+1,0+4, etc. Your rule destroys information. I don't think this happens with particles. At least not with balls, there is conservation of momentum.You can calculate back the exact date of a solar eclipse 2000 years ago. It is only limited by the limit of accuracy of your data.

[danielsondanielson]

But by saying previous I am not waving the idea of multiple pasts aside completely. If the hard determinism is true, then the state of universe at any moment T is a function F of its state at the moment T-dT. But it doesn't automatically imply, that F is a bijection, i.e. that also some inverted function f exists, for which it is true, that the (T-dT) state of universe is a function f of the T state. At the end of a day, we'd have to ask Laplace's demon, if it works that way in "real" universe.

[danielsondanielson]

I'd like to modify my previous comment a bit. Sure, in your ball example you can introduce some arbitrary rules, under which you can get to particular state of such universe in more than one way. Indeed, if the balls become adjacent, you can even stop them. But such arbitrary rules would differ from the laws of classical mechanics, let alone from the principles of quantum mechanics. I can't help myself, I am still afraid you will stay quite lonely in your "multiple past - single future" theory.

[danielsondanielson]

I am not sure if you exactly defined any exhaustive set of rules for movements of the two balls - but I would rather believe, that any clear, unambiguous set of rules was not defined here. The question is, if it's theoretically possible to define rules in such way, that there is only one possible future at any moment, but more possible pasts. I would still doubt about it - in Laplace's determinism, the time is strictly one-dimensional and linear. I am afraid you can do nothing about it.

[spiggitybap]

Do determinists say that my future action is predetermined? Or just that the present state of things is determined by prior events?

[modelmark]

one can not be valid without the other. in the future your current future events will be in the past. According to the first statement they ought to be defined by their past.

[spiggitybap]

I'm not asking whether past events have bearing on future events; like you said, that's a given. I'm asking whether determinists hold that future events are already and always predetermined, or whether they believe that at any given currency, I can willingly influence future events such that they were not predetermined before my willful action.

[modelmark]

i'm afraid you did not get what I was driving at, but I have no better way of putting it.

Do you believe reality is consistent? That the laws of nature remain constant?

[spiggitybap]

Don't bother "putting it" any way, it was a simple question. I'm not interested in debating, I'm just wondering what determinists believe.

Obviously, the course of matter is influenced by the course of other matter. I'm wondering if determinists carry that over from non-thinking matter to rational purposeful human action. Particularly, do they reject free will?

[modelmark]

it is irrelevant what people believe, if you do not know why they believe it. How would you determine it is true? Taste the believe in your mouth and see if it 'feels' right?

yes, determinists believe that cause and effect holds for all matter, both carbon atoms in your head and outside your head obey cause and effect and this means there is no free will in the sense of a will 'free' from cause and effect.

[spiggitybap]

Thank you. Also, that was confusing, as I'm not interested in their reasoning (which I can learn if I choose to elsewhere).

Are you saying that determinists believe that the choices my potential son will make were determined before I was born? Do determinists believe that whether I will even have a son was determined before my great great grandparents were born?

[modelmark]

I think a persons beliefs are not as relevant as the method he used to get those beliefs. If he used tarrot card reading, I am not so interested in his beliefs, if he uses the scientific method, I am.

Yes, determinists believe that cause and effect are universal, so it holds for all events in space time, including the one's you mentioned.

[fede2]

anaother cool name for multiple past theory: cosmological anarchy

[TimerTwin]

In deterministic systems where the past state does not impact the future state entirely, then it can move in only one direction.

In other words, the information of the past is destroyed. Not just disgregarded, but completely destroyed.

The reason this system is unidirectional (can only go forwards, but not backwards) is because of the ad hoc rule of ball collision. Stated differently, your universe does not have a conservation law. Something is destroyed, not conserved.

Wut do ya think?

[TimerTwin]

On second thought, disregarding the past state is the same as being completely destroyed.

[sharperguy]

I think you may have to do-do this video with momentum included to quieten people who claim that it invalidates the theory.

I like this theory and I am wondering what physics has to say about the reversibility of determinism.

[dnoohi]

Your mistake is simple, you did not account that dots should influence the environment.

Every move in this example is independent of everything, that is not realistic.

This example has no analogy in the real world where everything influences something thus revealing the previous state through the interaction with the surrounding.

[sharperguy]

In this simple example, the dots are assumed to have no influence on their environment except upon eachother (because they are the only things which do anything in this universe).

Of course in a real situation it would be almost infinitely complex but it is still possible that such a situation could occur where both sets of initial conditions could lead to the same effect in all respects including environment.

[dnoohi]

Are you sure, please name at least one situation where two different actions in the real world have the same influence on the global environment?

Keep in mind differences down to the quantum level, as far as I can think of there is no way to have two different actions and same displacement in universe.

[jagmarz]

The weak point here is that you have demonstrated that there are a set of deterministic rules that are not reversibly deterministic. While interesting in that you've proven such rule sets may exist, you've demonstrated nothing about whether the physical rules we currently know meet the same criteria. That is, do the physical laws fall into this same class.

[jagmarz]

Additionally, as others have sort of nitpicked, the static pictures don't indicate the momentum of the balls, which means you haven't fully captured all the information relevant to the laws under which you operate.

BTW, your laws would still be reversally indeterminate. Consider the motion just after the balls "touch" and start heading for the walls. The motion before they became "touching" would be lost after the touch.

[jagmarz]

But after all of that, I have to question the value of this line of thought. Even the present state cannot be known deterministically, so it's kind of meaningless to speculate which "past" could have led to "now".

Far more useful is the fuzzy approach where we ask what are the necessary characteristics of the past that led to now. One clear example is that we can know with certainty that, in any possible past, both you and I were born. So there are necessary, deterministic knowable past events.

[juliecranford]

What this reminded me of was that when you have a finite number of points on a graph, there's an infinite number of functions that could fit them. It freaked me out when I first realized it. Actually, it still freaks me out. How do we ever know anything?

[NeutrinoideReturns]

Nice demonstration of Stephen Wolfram automatons. In my opinion deterministic arguments and Free Will is a big fat false dichotomy. Determinist arguments try to explain how the mind works and the free willers are just talking about one aspect of the mind. Both don`t take in consideration the full ecosystem of the mind. And compatibilist don`t help by trying to fit a round peg in a square hole.

[canerdc]

1- Your geometry is wrong.

2- You can not (you didn't but said so) only look at the positions, must also measure the momentum.

Reversely deterministic argument still holds!

[dakshinamurti]

Quite possibly true, and that is the first thing I thought. But how is it possible to capture momentum with a single "photograph"? Doesn't it take at least 2 photographs for you to see which way a ball is spinning?

[canerdc]

It depends what your "photograph" records. If you only record the visible light or even only electromagnetic radiation, that gives you a slight information about the momentum of the objects those of which emit radiation.

But we know they can have momentum without emitting radiation. In this perspective the "photograph" must also record the shape of the space including electromagnetic radiation. This way it is possible to measure the momentum of every object (as we know). see. "dark matter" :)

[TheEfkk]

The point is that you forgot that you also need momentum in addition to position (and rules) to predict the movement of particles. If you have the momentum and the position, you can trace their trajectories back in time precisely (classical mechanics is time reversible). Thus, multiple pasts theory is invalid.

[ZamatoElite]

I think I understand what you are trying to say.

Sure there is multiple ways the balls can travel to get to the current position (but only in your very simplistic framework with 2 variables, with more variables the multiple past is INCREDIBLY unlikely, pretty much impossible), but that is irrelevant because you are tracing the balls movements backwards. By tracing them backwards, you will know which past was valid and which one was invalid.

I'm still a little unsure what you are saying.

[ChrisBovington]

This is a good example, but you made one small error. You had the red ball start in the top left corner, against both the left and top walls - but after the collision it moved to the left wall. That didn't fit the rules you set.

[canerdc]

Yes he made an angle error which completely ruins the physics of the artificial universe.

[Mastikator]

*Lifts one eyebrow*

Fascinating.