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Loop quantum gravity (LQG), if I understand correctly, describes time as emerging from the interactions of quanta of the gravitational field that can be described by spinfoam networks. (See photos)

We know time moves less quickly at sea level than it does atop a mountain. So, if "time" in LQG is just a measure of interactions, is LQG saying that there are less of these "interactions" taking place at sea level than atop the mountain?

In other words, the more mass density, or the more the gravitational pull, the less "interactions" there are in LQG?

This would be an interesting way to see the world. It would mean, to make a coarse analogy, that at sea level, we can "play" or "interact" with less sand than we can atop a mountain. Or to put it another way, the soap-bubble like spinfoam networks that make up our bodies in a gravitational field can blow less bubbles at the seashore than they can at the edge of space.

SP enter image description here

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Your initial premise is wrong. It is not the case that Loop quantum gravity:

describes time as emerging from the interactions of quanta of the gravitational field that can be described by spinfoam networks.

In fact all approaches to quantum gravity share the same fundamental problem that the origin of time is somewhat mysterious. This is often called the problem of time. If you are interested there is an excellent review in The Problem of Time in Quantum Gravity by Edward Anderson, though this will be too detailed for many of us.

At the moment we simply don't know how the classical concept of time emerges from quantum gravity, but then we don't understand quantum gravity so perhaps that is not surprising.

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  • $\begingroup$ While it is true that macroscopic time emerges from Quantum Gravity through a yet-to-be-determined mechanism (thermal time?), microscopic time as a "rate of change" still exists in LQG. It is encoded in the correlations between partial observables, and thus is as much a property of the quantum gravitational field as, for example, curvature, or gravitational pull. $\endgroup$ – Prof. Legolasov Jun 28 '17 at 4:38

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