Do miracles violate the laws of physics? I asked a Christian today whether he believed that Jesus turning water into wine literally happened, or was just a metaphor. He said it literally happened, and also that other miracles literally happened, such as Jesus dying and coming back to life.

Some miracles described in the bible appear to violate the laws of physics. For example, in turning water into wine, I assume carbon atoms would have to appear where they did not exist before.

Do Christians have an opinion on what happened? Do they believe


The laws of physics were obeyed, and that our understanding of them is merely insufficient to understand what happened.
God does not break the laws of physics, but he changed the laws of physics temporarily such that those laws permitted certain miracles to occur.
God is not only able, but is willing, to break the laws of physics that he created?


The latter two sound like God being inconsistent, and the first one raises the possibility that if humans can understand the science fully, it may (or may not) be possible to replicate what he had done.
The laws of physics are certainly quite different from moral laws.  In fact, the Bible never refers to the laws of physics as "laws".  We see them as laws, because we are bound by them and are unable to break them.  We don't obey them based on our own volition.  

Moral laws define what we ought to do, but we are under no compulsion to obey them.  We have a choice.

We obey the laws of physics because they bind us to them.  We obey moral laws because we bind ourselves to them.

So, the idea of God "obeying" what we describe as the laws of physics is really an absurdity.  These laws govern the physical universe--not the Maker of the physical universe.

This is a very significant distinction, because I have heard someone make the claim that if God breaks His own laws (of physics), then He is guilty of sin for breaking the law.  This is a completely false statement, though, because the laws of physics are distinct from moral law. Breaking a moral law is, by definition, immoral, but this is not true of the breaking of physical or natural laws.  Breaking a natural law would simply be "unnatural", or, more appropriately, "supernatural".

The Maker of the physical universe certainly has the power to create new matter according to His own will, as in the case of the Feeding of the 5,000.  He can change matter according to His will as well, as in the case of the Turning of the Water into Wine, the healing of the blind, the raising of the dead, etc.  

Yet, His authority is not merely over the physical world, but over the spiritual realm as well, as demonstrated in Jesus casting out demons.

So, God is not confined by what we happen to refer to as the laws of physics.  They are laws the govern the physical universe.  They do not govern God Himself.