Does free will contradict the laws of physics?

People often say that free will contradicts the laws of physics because free will implies a 'garden of forking paths' where you can do A or B. But the laws of physics imply that either history was fixed at the time of the Big Bang or that where chance exists it is merely randomness and probability. Where does that leave free will?

An interesting way of imagining how free will can be compatible with the laws of physics comes from quantum mechanics. The 'Schroedinger's cat' idea gives a good account of it (from Wikipedia):

Schrödinger's Cat: A cat, along with a flask containing a poison and a radioactive source, is placed in a sealed box shielded against environmentally induced quantum decoherence. If an internal Geiger counter detects radiation, the flask is shattered, releasing the poison that kills the cat. The Copenhagen interpretation of quantum mechanics implies that after a while, the cat is simultaneously alive and dead. Yet, when we look in the box, we see the cat either alive or dead, not both alive and dead.

This article explains a bit more about why the cat is both alive and dead:

The principle of superposition states that if the world can be in any configuration, any possible arrangement of particles or fields, and if the world could also be in another configuration, then the world can also be in a state which is a superposition of the two, where the amount of each configuration that is in the superposition is specified by a complex number.

There is superposition with regard to the Geiger counter detecting radiation, because it's a subatomic phenomena. Therefore, after a while an atom has in some sense both decayed and not decayed, releasing and not releasing radiation. Thus, after a while the cat is both dead and alive.

In the Copenhagen interpretation of quantum mechanics, a system stops being a superposition of states and becomes either one or the other when an observation takes place. This experiment makes apparent the fact that the nature of measurement, or observation, is not well-defined in this interpretation. The experiment can be interpreted to mean that while the box is closed, the system simultaneously exists in a superposition of the states "decayed nucleus/dead cat" and "undecayed nucleus/living cat", and that only when the box is opened and an observation performed does the wave function collapse into one of the two states.

Schroedinger's cat illustrates how quantum mechanics seems, at least superficially, to allow for something that sounds like a 'garden of forking paths'. The cat is both alive and dead, two contradictory possibilities exist, and our conscious observation forces reality to 'choose' one. Perhaps our brain has many possible configurations and our consciousness/the soul can make out of them one reality?

But does quantum mechanics apply to the workings of the brain? Some scientists have come up with theories of how it could (link).

So with free will, imagine that until our consciousness/soul affirms a value, e.g., 'I think it's important to be truthful', then the neurons in our brain are simultaneously affirming a 'truthful' brain state and a 'not truthful' brain state. But after the conscious decision is made then the 'truthful' brain state 'resolves' into being - just like the cat is alive or dead only when the scientist looks into the cage and 'forces' an answer.

This type of analysis doesn't explain what free will is, it just indicates how the soul or consciousness might be able to change the brain using free will. (Libertarian) free will's workings would still be beyond our understanding.

I apologise in advance for my scientific ignorance if this idea is fundamentally flawed, but, as others have said, it seems that a genuine free will can be compatible in theory with the laws of physics.

(Edited 5 April 11).

Location heaven versus state of mind heaven

There's a common perception out there that heaven (or eternal life in the new creation) is just a place. There's a common view that all God has to do to let people into heaven is put them in heaven. And that God doing this would instantly make hell empty.

The Bible also talks about heaven as a state of mind rather than a location:

Romans 14:17: For the kingdom of God is not a matter of eating and drinking, but of righteousness, peace and joy in the Holy Spirit,

Psalm 16:11: You have made known to me the path of life; you will fill me with joy in your presence, with eternal pleasures at your right hand.

Psalm 36:8-9: They feast on the abundance of your house; you give them drink from your river of delights. For with you is the fountain of life; in your light we see light.

Luke 17:20-1: Once, having been asked by the Pharisees when the kingdom of God would come, Jesus replied, "The kingdom of God does not come with your careful observation, nor will people say, 'Here it is,' or 'There it is,' because the kingdom of God is within you."

In the Bible, heaven and eternal life also involve one's mind or self being deeply and intimately connected to God.

So heaven isn't just about going to a heavenly location in a spiritual dimension, it also involves a state of mind. Judging from the verses above, this state of mind involves experiencing whatever happiness or contentment God feels through being reconciled fully to God.

The question is: how do you get reconciled to God to experience a state of mind heaven? The problem is that our wrong actions (sin) separate us from the kind of closeness to God that is heaven. The Bible's answer to this problem is that God/Jesus Christ "bore our sins in his body on the tree, so that we might die to sins and live for righteousness" (1 Pe 2:24). This meant God could "[make] [us] alive with Christ" dealing with the problem (Col 2:13) - meaning that although we can't avoid sinning in this life (1 John 1:8), our fundamental orientation has changed.

This analysis says that going to heaven isn't simply a matter of God letting someone into heaven. Intentions, thoughts, desires, and so on need to be different as well, and a two-way loving relationship needs to exist between us and God.

Some thoughts on the argument from apparent design

I thought I would mention an argument for believing in God which I find quite convincing, an argument for the design of the laws of physics. General arguments for God are important because if God exists, then it's not a big step to Christianity out of other religions, especially with arguments like the one that uses historical evidence to support Jesus' resurrection.

I'll quote part of an article which is quite good on this subject, available here.

...The world is conditioned principally by the values of the fundamental constants A (the fine structure constant, or electromagnetic interaction), mn/me (proton to electron mass ratio), aG (gravitation), aW (the weak force), and aS (the strong force)...

For example, if aS were increased as much as 1%, nuclear resonance levels would be so altered that almost all carbon would be burned into oxygen; an increase of 2% would preclude formation of protons out of quarks, preventing the existence of atoms. Furthermore, weakening aS by as much as 5% would unbind deuteron, which is essential to stellar nucleosynthesis, leading to a universe composed only of hydrogen. It has been estimated that aS must be within 0.8 and 1.2 its actual strength or all elements of atomic weight greater than four would not have formed. Or again, if aW had been appreciably stronger, then the Big Bang's nuclear burning would have proceeded past helium to iron, making fusion-powered stars impossible. But if it had been much weaker, then we should have had a universe entirely of helium. Or again, if aG had been a little greater, all stars would have been red dwarfs, which are too cold to support life-bearing planets. If it had been a little smaller, the universe would have been composed exclusively of blue giants which burn too briefly for life to develop. According to Davies, changes in either aG or electromagnetism by only one part in 10^40 would have spelled disaster for stars like the sun.

etc...

But what about the idea that there are an infinite number of universes? If there are an infinite number of universes, then our laws of physics are nothing special, because they must happen somewhere.

I think there's a really good article, from Discover Magazine, on the idea of the multiverse from the point of view of modern physics, here.

Here's some key quotes about the issue:

...Call it a fluke, a mystery, a miracle. Or call it the biggest problem in physics. Short of invoking a benevolent creator, many physicists see only one possible explanation: Our universe may be but one of perhaps infinitely many universes in an inconceivably vast multiverse. Most of those universes are barren, but some, like ours, have conditions suitable for life...

...Nobel laureate Steven Weinberg, a physicist at the University of Texas, agrees. “This is the one fine-tuning that seems to be extreme, far beyond what you could imagine just having to accept as a mere accident,” he says.

Dark energy makes it impossible to ignore the multiverse theory. Another branch of physics—string theory—lends support as well. Although experimental evidence for string theory is still lacking, many physicists believe it to be their best candidate for a theory of everything, a comprehensive description of the universe, from quarks to quasars...

...Linde’s ideas may make the notion of a multiverse more plausible, but they do not prove that other universes are really out there. The staggering challenge is to think of a way to confirm the existence of other universes when every conceivable experiment or observation must be confined to our own. Does it make sense to talk about other universes if they can never be detected?...

...Rees, an early supporter of Linde’s ideas, agrees that it may never be possible to observe other universes directly, but he argues that scientists may still be able to make a convincing case for their existence. To do that, he says, physicists will need a theory of the multiverse that makes new but testable predictions about properties of our own universe. If experiments confirmed such a theory’s predictions about the universe we can see, Rees believes, they would also make a strong case for the reality of those we cannot...

So basically the multiverse makes sense as a theoretical idea but it has no real evidence for it in an empirical sense.

So where does one go from there?

I guess to some extent it could be a matter of personal taste, God or multiverse. But I have one more thought on the issue.

One of the traditional problems with asserting the existence of God is that it can easily fall afoul of Occam's razor. Occam's razor is the famous scientific principle that says you should not multiply entities unnecessarily.

A practical example of Occam's razor is the belief, 'My friend keeps ordering hamburgers because they like hamburgers', is more parsimonious than, 'My friend keeps ordering hamburgers because they made a bet with someone to eat 500 hamburgers before the end of the year', because the second one has more (and more complicated) entities in it as an explanation.

If you can explain everything with only one universe, then God has problems with Occam's razor. But if the only alternative to God is literally an infinity of other universes, then it's not clear God will be badly affected by Occam's razor. Because 'infinitely many universes' is a pretty big entity to assert, as big as an infinite God perhaps.

So, I would imagine, if you believe that there's a multiverse, then atheism no longer gets to use Occam's razor.

Normally atheism gets an inherent advantage over theism as the default position from Occam's razor. But with the multiverse that inherent advantage is lost, and neither position gets any inherent advantage over the other.

So the atheism-theism debate is then like thinking it will come up heads on a coin toss rather than tails, in terms of overall plausibility.

Why is it so hard to describe heaven?

Why can't Christians come up with a really fantastic description of heaven (or rather the new heavens and new earth)? Here is my attempt to explain a large part of the reason.

Something interesting about our happiness in this life is that it is very, you could say, 'temporal'. That is, people's happiness experiences a huge issue with boredom. Some people would be happy to live forever as long as they could keep experiencing new things forever, but in polls a lot of people say that they wouldn't want to live forever even if they could do so.

I believe this is because human happiness is not naturally hardwired for eternity. Our ability to be happy cannot sustain us for that long. E.g. it's a relatively common motif in horror stories that someone is condemned to live forever even though they can do whatever they want.

But it's interesting to note that God is probably not at all like this, if any God exists, because otherwise God would have gone completely insane with boredom. In most theologies God is eternal and outside time, and thus God has already lived for an infinite length of time. If God's happiness can't handle eternity, then God would be mad with depression (Isaac Asimov actually wrote a short story based on this premise called "The Last Answer").

And this leads to the conclusion that, because God is naturally eternal or for some other reason, God's happiness is a kind of happiness we have no experience of in this world - apart from through the Holy Spirit's sense of peace, if Christianity is to be believed. This can be indicated, if any God exists, from the reasoning above (unless Isaac Asimov's short story is right!)

Thus I conclude that part of why heaven is such a great place is because we have access to this divine kind of happiness that allows someone to be at peace and contented forever without being insane or something like that.

See Rom 14:17: "For the kingdom of God is not a matter of eating and drinking, but of righteousness, peace and joy in the Holy Spirit,"

1 Cor 2:9: "However, as it is written: "No eye has seen, no ear has heard, no mind has conceived what God has prepared for those who love him""

Psalm 16:11: "You will make clear to me the way of life; where you are joy is complete; in your right hand there are pleasures for ever and ever."

Psalm 36:7-8: "How precious is your unfailing love, O God! All humanity finds shelter in the shadow of your wings. You feed them from the abundance of your own house, letting them drink from your river of delights. For you are the fountain of life, the light by which we see."

Rom 8:18: "For I consider that the sufferings of this present time are not worth comparing with the glory that is to be revealed to us."

We get this happiness through being connected to God through His Holy Spirit. And this is made possible by Jesus Christ removing our sins when He took them into himself on the cross (1 Pe 2:24).

I believe this is a significant part of the reason why heaven is so hard to describe in a really fantastic way.