It’s hard not to end up treating heaven or eternity as spacetime beyond spacetime, and attempts to get beyond this risk understanding it simply as a vague and confused temporality. We used to pose the question whether heaven was a place or a state of being, but “being in space” is a way of being, so what was the point of the question? The distinction only amounted to the difference between a concrete and general account, rather like asking whether spaghetti was pasta or food.
In the Dantean vision of things heaven is up there, though even Dante refuses to be pinned down to this, insisting early on in Paradiso that the distinctions and orders one sees in heaven are in some sense overcome or metaphorical. So while Dantean Purgatory is literally a seven-story mountain, heaven is not literally ascending spheres. We detect a similar way the Gospels explain Christ’s corporeity as somehow true corporeity without its limits: Christ ascends into heaven, but only after resurrection appearances make it clear that the resurrected body is not subordinated to spatiotemporality (by his appearing in locked rooms, hiding himself in plain sight on the road to Emmaus and then dematerializing at dinner, etc.)
The body of Christ is necessary for the working of the sacraments and so must exist and be alive, but we can’t place it in some spacetime beyond spacetime, which is at least superfluous and contradictory. It makes no difference if we want some straightforward spacetime of the Dantean up there or if we work out a more exotic modern physical theory. Putting Christ in a larger universe in which our universe is a membrane is as unsatisfying as putting him in orbit, and looking for Christ with a quirky and brilliant algebra is really no different than trying to get to him on a ship or, more fittingly, to build a ziggurat that reaches the divine realm. For all that, what do we do with our need for the body of Christ to be the causal foundation of sacramental life?
All analogies for the Incarnation hide more than they reveal, but the best one we have is the union between the human soul and body. Though soul is intrinsically spiritual and so in itself of a different essence than matter, the substantial unity of soul to body allows matter to perform a properly spiritual action. Thought is immaterial, but brains think. The union of the Word and Christ’s body is also of things as forever distinct in essence as spirit and matter, but the union nonetheless allows his body to perform a properly divine action. The body of Christ is joined ontologically to the Word, and the Word is everywhere.
The obvious objection to all this is that it asserts a bodily non-bodiliness, which is perhaps the only option worse than simply imagining Christ in orbit somewhere. But this might suffer from an account of bodies too dominated by imagination. Whatever affects physical entities according to a principle intrinsic to it is a body, and through the Incarnation the Word acts on bodies not only by spiritual agency, but according to a physical principle he has made intrinsic to himself. Again, the body with a human soul is both body and yet does not share in all the limitations of body; and the corporeity of Christ, at once truly corporeal and yet ubiquitous, is the limit case of this.
So perhaps the right approach to Christ’s corporeality is not seeking some spacetime beyond spacetime, whether in a Dantean heaven or a modern theory of multiple dimensions, but to rather to see his corporeality perfected by its incorporation into the ubiquity of the Word. In fact, this is the same sort of incorporation that the Christian himself hopes for, and which can be enjoyed at least psychically in the time before the resurrection, which is why imagining that one divides the attention of the saints when multiple persons ask for intercession is absurd and impious.