When considering time and eternity, I cannot help but think as a physicist as well as a theologian. From a physicist’s point of view, a time-bound God is a curious phenomenon.
You may want to read Time and Eternity first.
This is not the place for a primer on Einstein’s theory of special relativity, but one key observation to note is that you simply cannot separate time and space. Both are part of one and the same matrix that frames our existence. This matrix is four-dimensional: one time dimension plus three spatial dimensions (height, width, depth). Now special relativity tells us that you cannot keep them apart. Specifically, different observers in motion relative to one another will disagree on what precisely is time and what is space.
Let’s think about it with an illustration. The diagram on the right probably looks confusing at first glance, but start by focusing on the green frame only. This is your own frame of reference. The horizontal axis represents space (x); the vertical axis represents time (ct).
Now your wife Alice is greeting you (A), and coincidentally, your best friend Bert is also greeting you (B). Because you’re a physicist, you can’t help but notice that Alice and Bert did so at exactly the same moment in time. In other words, A and B sit on a horizontal line (in this case, the x axis). The two greetings are separated only by space, not by time. What an amazing coincidence!
It so happens that your friend John, who has no regard for speed limits, is just rushing by in his 0.5 lightspeed car and observes the very same events. When you meet him again in the pub the next day, you are still gushing over the fact that Alice and Bert greeted you at exactly the same split nanosecond in time.
“Nonsense,” says John to your great surprise. “Bert only hailed you later.”
Is he wrong? No. Because of his motion relative to you, his frame of reference was the red frame, and he experienced space and time differently. In the red frame, A still sits on the x’ (space) axis, but B is located slightly above it, i.e. for John, B occurs later in time.
Who is right? You both are. In special relativity, there is no privileged frame of reference. Simultaneity is simply not a well-defined concept for events in different locations.
The omnipresent, omnitemporal God
So time and space cannot be disentangled from each other; they mix differently for different observers. The immediate implication is that you cannot say ‘God is subject to time’ without also saying ‘God is subject to space’. It’s the same stuff.
Such a God breaks the beautiful symmetry of special relativity by introducing a privileged divine reference frame. Should God’s frame be the blue frame above, the Almighty will disagree with both John and yourself. As far as he is concerned, Bert in fact hailed you before Alice. It’s a good thing he is still omnipresent, else you would have known about Alice’s greeting before God did!
Stump and Kretzmann attempt to get around such baffling consequences by insisting on the uniqueness of the concept of duration as experienced in eternity and thus the eternal reference frame as distinct from the many possible temporal reference frames. ET-simultaneity then defines a simultaneity relation between these eternal and temporal entities so that an eternal entity (God) can still be ‘present’, both causally and relationally, to a temporal entity (such as you and me). It is, however, far from clear how the “eternal reference frame” relates to the reference frame concept of special relativity, even analogically; or how ET-simultaneity can really be understood as simultaneity at all seeing that it is intransitive, one of the referents being eternal. It strikes me that problems are being moved, not resolved.
The implication of this is that the God of open theism has a definite shape in spacetime. Consider the three diagrams above. The leftmost one represents the (Newtonian) way we usually think about time and space. The red line represents us speeding from past to future; the blue surface represents all of the present time – and thereby it would also represent the omnipresent God. He has his being in this hypersurface, a 3-dimensional sheet in 4-dimensional spacetime.
But the first picture is too simple. In Einstein’s theory of special relativity, space and time do not allow for such neat separation and the picture gets a good deal more arbitrary. God may in fact correspond to the wavy hypersurface in the second diagram. Or if God were different, or if the observer were different, or both, God might inhabit the hypersurface of the third diagram. It’s the shape of God, and what he looks like depends on your vantage point.
To mix things up even more, this surface could also, in principle, change shape over time. God’s subjectedness to time, and therefore to space, necessarily creates scope for movement of the divine hypersurface.
A God who experiences time is surprisingly arbitrarily, and surprisingly intimately, present in his creation. He breaks the symmetry of physics by introducing a privileged frame of reference. God can even be said to move in the sense that the divine hypersurface might conceivably change shape over time. The unincarnate God, then, takes on attributes of particularity, shape and movement in creation that are traditionally associated only with the incarnate God in Jesus of Nazareth.
The God of open theism and Einstein is a remarkable God indeed.
In the next instalment, we will have more fun with God and Einstein’s theory of General Relativity.