we don’t need to get that pedantic. It’s pretty clear that we’re talking about jumping forward or backward in time and not simply letting it progress naturally.
the point about “free will” means (to me) that much of what I will do in the future is unknown to me. I don’t know precisely what I will do 10 minutes from now. were I to jump forward in time- say, a week- then that would mean everything that happened in that duration would have to have been pre-determined. I can plan for things, but they aren’t guaranteed to happen. I plan to get in my truck and drive to work on Monday, same as I do every weekday. But there’s a chance that a truck will lose a wheel which slams into my vehicle, damaging it to the point I can’t get to work. If I jump forward in time from today to next Saturday, what happened on Monday? did my truck still get hit by the loose wheel? or did I leave a couple of minutes later and miss the event entirely? 'cos as of right now I don’t know precisely what time I will leave for work on monday. yet for the wheel to strike my vehicle, I will have to be pretty much in exactly the right (wrong?) place at exactly the right time. If I’m not, it hits someone else’s car. or bounces through traffic and just lands in the ditch.
I simply interpret “free will” as meaning what I do and experience is not part of some pre-determined master plan. e.g. in my example above, there’s no “master control program” which has it in its script that “on Monday, March 12, 2018, at 07:43.2843 a wheel will come loose from a JW Hunt trailer and strike jz78817’s personal vehicle in the grille and disable it by damaging the radiator.”
Why would jumping forward in time require any more pre-determination than going there at the usual rate? While you’re in the process of jumping, the rest of the world goes on making whatever decisions it does or doesn’t make, and when you arrive there, the decisions (if any) have been made.
But you weren’t there to do those things, so they were determined without you.
The fact that you jumped forward in time is itself predetermined, and is taken into account in the construction of the future.
No, you don’t know. But that doesn’t mean that it is not predetermined. There will be a long series of events of individually infinitesimal significance that will all lead to that moment and the inevitable result is that you will leave for work at 8:02:15.39.
Part of the argument against free will is the idea that a person is a finite state machine. On election day, you walked into a voting booth and cast a vote for president. You think you have free will to make whatever decision you want, but in fact your voting decision was based on who are you were when you were born plus the sum of all your experiences in life. If this were not true then everybody would be the same. If you were in a Groundhog Day scenario and with exactly the same life experiences, mood, and genetic makeup you would cast the same vote every single time. So where is the free will? If you grew up in a conservative town with conservative parents then chances are you would vote conservative. If you grew up in an urban area with liberal parents then maybe you would have taken the same information but decided to vote liberal. But those decisions were painted by your experiences. So where is the free will in that?
The majority of people have the same religion as their parents. They say they are exercising free will, but aren’t they simply molded to it when they are impressionable?
I am not smart enough to read the OP’s linked article and make any sense of it, but if time travel is possible, it has to be one-way only. Are you stuck in the past? Are you capatulted into the future? Either way you have to stay there.
Because, think about it, if two-way time travel was possible, and was discovered in the future, then we could know about it now.
What do we want? Time travel!
When do we want it? Whenever…
The past is not a thing, a place, stuff. It is not a physical reality. It is information. Information that formed the how and the why of is.
You see that stretch of road ahead? What you see is how it was a few jiffies ago. You will be there in about three seconds (with a vanishingly small probability error). You probably failed to notice the squirrel on the shoulder which very well may run out and commit suicide-by-tire (or possibly run under your car, missing the tires completely). What you see is the very recent past, rapidly converging toward your present. Your local observations tend to be highly consistent, so the actual present becomes a reality with indistinct boundaries.
What is this big rock doing lying out in this open field? We can study it and determine that it must have been spit out of that mountain a long time ago. More detailed analysis may reveal about how long ago that happened. That is the past: information.
The further you get in time and distance from an event, the less information is available about that event. In fact, we often find that what we knew was wrong and our recorded information is revised to fit a better model. Our understanding of the past is imprecise and variable, and probably always will be.
Which is to imply that “a butterfly flaps its wings and …” is fantastical nonsense. Increasing separation of events results in greater diffusion of the cause-effect relationship. The past is not scribed in stone (which weathers away anyway), it is a shifting foam of spheres of probability.
Hence, the future is not prescribed. Cause-effect vectors are not straight lines, they fan out from the source and fade into indistinction.
4D-spacetime is a useful model for doing the math, but a “dimension” is just an abstraction: a mathematical tool. In order to time-travel, we would have to acquire a present-reality in the information field of the past or the future. Is that possible? Can a present-reality that is non-contiguous to the existing present be established and reached? And, more importantly, if what is known about the target position is as unreliable as our historic knowledge has shown, how do we even set aim for that position?
THANK YOU. I hate the “butterfly flaps its wings” meme. The reason it is flat out wrong is that let’s take another example of that meme. You have a tall pile of, say, sand and 1 more grain is going to set off an avalanche.
Well what happens if you delete that 1 grain from existence?
Another grain or other slight disturbance will happen shortly thereafter and the avalanche still happens. What creates the avalanche was not the single grain of sand. It was the energy gradient set up by all the previous grains of sand that created a system on the tipping point.
Similarly, major weather systems are energy gradients created by differential heating by the sun. A butterfly might be the nucleus that starts a tornado - but if you kill the butterfly before it sets off the tornado, another slight disturbance is bound to happen and start a tornado anyway. (albeit at a slightly different time and place)
This implies that if you could go back and stop archduke ferdinand from being assassinated, ww1 would have still happened, with just a slightly later start date.
The butterfly effect is not that it takes butterflies to start tornadoes, rather it is that, due to there being after time an extreme sensitivity on initial conditions in chaotic systems, such as those that model weather, it is entirely conceivable that a tiny peturbation on the scale of a butterfly flapping its wings could be the difference between a tornado developing and not developing after a certain time. It certainly wasn’t invented as a premise for a franchise of B-movies, it is a pedagogic description first coined by mathematician and meteorologist Edward Lorenz, a pioneer of chaos theory.
Whenever the discussion begins to involve really advanced mathematics or really deep philosophical theories about the nature of reality, I can only parsley follow along.
Or to put it another way: If you have two worlds with exactly identical initial conditions of wind, temperature, clouds, etc., except that there’s a butterfly’s-wings’ worth of difference between the two, within a week, those two worlds will be having completely different weather. One might have a hurricane, while the other has completely clear skies.
No. That’s the “straw that broke the camel’s back” idea, which is an obvious and not particularly interesting one, and is certainly not the premise of chaos theory. The premise of chaos theory – as others have subsequently implied – is that a small event produces a cascade of consequences that lead to a major change in the state of a complex system.
Possibly, but the hurricane still hit somewhere. A butterfly flap can’t affect the energy gradients that create them. That energy has to be dissipated.
But a hurricane that hits point A at time X is a completely different event than a hurricane that hits point B at time Y, and can have completely different consequences. The fact that you consider them the same thing is a failure of the human tenancy to search for patterns. From a purely physical point of view, the two events are utterly dissimilar.
Eh…maybe. If you visualize the landscape of energy gradients like a 2d contour map, you realize that a small effect can only very slight change the height of an element on that map a tiny amount.
So in reality the butterfly will almost never make a difference. The system is going to converge on a minima and it takes a very large nudge to make the minima it hits be a different one.
If you image it like a pool table, only if the ball is exactly balanced between 2 outcomes will a tiny force make a difference.
This is definitely true for simple neural network experiments. Change the initial conditions slightly and almost every possible change you make, the network will still converge on the same ultimate optima.
To be honest I question how much empirical verification this “chaos theory” has. Given how old it is, and how slow the computers they had then, it actually may just be wrong.
Eh. Objectively speaking, we’re just a insignificant rock orbiting a minor sun that will eventually grow and swallow us, and in the long run, nothing that happens here has any meaning. So what’s your point? That everything averages out at the end? Of course it does. You pull back to a large enough scale and nothing makes any difference.
Personally, from a human point of view, those blips can mean a lot.
I’m saying that I don’t know if there would *be *a blip in most circumstances. I’m saying that out of billions of butterfly wing flaps, most of them have no effect on the outcome. It’s only a small possibility that they would make a difference.
Yes, that’s what researchers thought until they studied it, too, which was why it was such a surprise when they discovered that it was almost always a major difference.
I’m trying to understand your beef with chaos theory: looking for examples of non-chaotic behaviour in certain systems hardly refutes the validity of chaos theory in other systems.
Chaos theory is a branch of mathematics so it doesn’t require empirical verification, though it is easy to verify empirically that certain physical systems exhibit chaotic behaviour, the classic example would be a double pendulum. Chaos theory is a big and very active area of applied mathematics, so I am not sure how it could be ascribed to the technical limitations in some early computer.