MWI interpretation and free-will compatible?

[Duplex]

TL;DR

An issue especially for those of you who prefer MWI and are convinced of your own free will.

I am in my self-driving car and approaching an intersection, where I can either drive to the right or left.
I choose to drive to the right.

There are two buttons on the instrument panel, R (ight) and L (eft).
I press R, and a QM random number generator is activated. My car drives to the right with 99% probability. (The RNG is biased, 99/1% instead of 50/50).

A QM measurement was made and a new universe was created, regardless of whether I pressed the R or L button.
The L-button leads to an identical RNG, but with 99/1% L-bias.

If I drive both right and left, then my free will has been lost, right?
As I can understand, MWI and the concept of free will are mutually exclusive. I can not both eat the cake and keep it.

Disclaimer: I'm not a physicist and I don't own a Tesla.

Moderators: Please, move this thread to the Q Interpretation Forum.

 

[PeterDonis]

I choose to drive to the right.

There are two buttons on the instrument panel, R (ight) and L (eft).
I press R, and a QM random number generator is activated.

These statements are inconsistent. Choosing to drive to the right is not the same as choosing to press one of a pair of buttons that each activate a QM random number generator with differently biased probabilities.

What you should say is that you choose whether to press the R button or the L button, and you choose to press the R button. That action that you choose does not determine which direction you go; it biases the probabilities (but the interpretation of these "probabilities" in the MWI is an issue for that interpretation), but that's not the same thing.

If I drive both right and left, then my free will has been lost, right?

No. You chose which button to press, and you pressed that button. That was your free will choice.

In one of the two branches that resulted from the quantum RNG (assuming we are using the MWI), you ended up going in the opposite direction from the one the button you pressed was biased in favor of (L when you pressed the R button), but you knew that was possible when you pressed the button. As above, your choice was which button to press, not which way to go; the best you could do was bias the probabilities for which way you would go, and you did that. Biasing the probabilities is not the same thing as choosing directly which way to go.

As I can understand, MWI and the concept of free will are mutually exclusive.

Where are you getting that understanding from?

In any case, if you want to test the MWI vs. free will, your scenario doesn't do that. The quantum effect needs to be inside your brain, in whatever processes underlie your free will choice, not inside some external object that you trigger by pressing buttons (or any other action). But if you try to construct a thought experiment along those lines, you will find that the quantum effect is no different from any other kind of "noise" in your brain processes, such as thermal fluctuations. Such "noise", if it is intense enough, might impair your brain processes in general, but it doesn't change what your brain processes are capable of when they are working properly.

 

[Duplex]

Thanks, PeterDonis, for a detailed and nice answer to my question, # 1, which I had some difficulty formulating at my B-level.

The reason I introduced an external QM RNG (Random number generator) was:
1. I thought the presence of an external QM measurement process was necessary.
2. to avoid a philosophical discussion about controversial, unproven quantum processes in the brain.

I realize I was wrong. An external RNG is an intermediary, as unnecessary as driving a truck by using a hamster and a carrot.
(Youtube: "The hamster stunt")

Duplex said:

As I can understand, MWI and the concept of free will are mutually exclusive.

Where are you getting that understanding from?

Just from my thoughts and experience of free will. Every day I create measurable physical results of my free will.

If I now use my free will to turn in one direction, then according to MWI a new world is also created where I turn in the other direction.

With multiple outcomes, hasn't MWI then erased the result of my free will?
Thus, are not MWI and free will mutually incompatible?

Admittedly, I have made a choice, but without results. My concept of free will is results-oriented.

(I assume that "I-Left" is an identical "clone" of I-Right with the same consciousness, knowledge, memories, experiences and "soul" and not a zombie without a soul.
I can see an issue here. Why is my consciousness only in I-Right, the one who choosed to drive to the right?
Speculation warning: If nothing else, a result of Darwin's theory of natural selection? The "clones" who were aware of each other quickly became psychotic and unable to survive the struggle for existence.)

It is possible that I have misunderstood something fundamental. If that's the case, I would be grateful to know what.

 

[hutchphd]

I also do not perhaps understand the nuances, but by your free will you have chosen

1. to make a decision
2. which branch "you" will follow

This seems to me to be rather empowering to your free will. What I don't really understand is: does every branching decision create a contrary doppelganger of ourselves.
This really does get out of hand rapidly but who knows?

 

[PeterDonis]

If I now use my free will to turn in one direction, then according to MWI a new world is also created where I turn in the other direction.

The MWI does not say this, unless there is quantum randomness involved in the process in your brain that determines which direction you turn. But if there is quantum randomness involved in that process in your brain--if, in effect, something like the random decay of a radioactive atom in your brain, or the random measurement of a qubit's spin being either up or down in your brain, is what determines which direction you turn--then you wouldn't say it was your free will choice anyway. For it to be your free will choice, your free will has to determine which direction you turn; and there is no room for quantum randomness in your brain processes to affect which way you turn if that is the case.

It is possible that I have misunderstood something fundamental. If that's the case, I would be grateful to know what.

You have failed to think through how your brain processes have to work, or how they cannot work, for you to have free will in any meaningful sense. See above.

 

[PeterDonis]

What I don't really understand is: does every branching decision create a contrary doppelganger of ourselves.

It depends on whether quantum randomness is involved in the "decision"; but if it is, you wouldn't call it a "decision" anyway. See my response to the OP just now.