See, we assume that time is a given externality, just a parameter that marches forward, and that the past already happened and the present, that moment “now” just slipped away into the past, and that the future is yet to come. But if we examine this carefully, again using the insights from feminist theory, from post-structuralist theory, and things that Cultural Studies has been telling us, and so on, and bring them into the physics here, what we can see is that what is going on actually is
the making of temporality. There are questions of temporality that are coming to the fore here. What we are seeing here is that time is not given, it is not universally given, but rather that time is articulated and re-synchronized through various material practices. In other words, just like position, momentum, wave and particle, time itself only makes sense in the context of particular phenomena. So what is going on here is that physicists are actually making time in marking time, and that there is a certain way in which what we take to be the “past” and what we take to be the “present” and the “future” are entangled with one another. What we have learned from this experiment is that what exists are intra-active entanglements. That is the only reason we get a diffraction
pattern again, by the way.
And importantly, the original diffraction pattern doesn’t return, a new one is created, one in which the diffraction (that is, entanglement effects) is a bit challenging to trace. So, the issue is not one of erasure and return.
What is at issue is an entanglement, intra-activity. The “past” was never simply there to begin with, and the “future” is not what will unfold, but “past” and “future” are iteratively reconfigured and enfolded through the world’s ongoing intra-activity. There is no inherently determinate relationship between past, present, and future. In rethinking causality as intra-activity and not as this kind of billiard-ball causality—cause followed by an effect—the fantasy of erasure is not possible, but possibilities for reparation exist. That “changing the past” in the sense of undoing certain discrete moments in time is an illusion. The past, like the future though, is not closed. But “erasure” is not what is at issue. In an important sense, the “past” is open to change. It can be redeemed, productively reconfigured in an iterative unfolding of spacetimematter. But its sedimenting effects, its trace, can not be erased. The memory of its materializing effects is written into the world.

(Barad, "Matter feels, converses, suffers, desires, yearns and remembers", 66)
What temporal futural imagineries can emerge in relation to an immanently closed horizon of the the "time afterwards"? How do we endure in this time? What is the relation to the trauma of foreclosure, if indeed we can use that term to describe the assault, or slow violence, on future deep time that may turn out to be the distinctive product of late capitalism?

[Enduring Time, Lisa Baraitser]
NIST-F1 is referred to as a fountain clock because it uses a fountain-like movement of atoms to measure frequency and time interval. First, a gas of cesium atoms is introduced into the clock's vacuum chamber. Six infrared laser beams then are directed at right angles to each other at the center of the chamber. The lasers gently push the cesium atoms together into a ball. In the process of creating this ball, the lasers slow down the movement of the atoms and cool them to temperatures near absolute zero.

Two vertical lasers are used to gently toss the ball upward (the "fountain" action), and then all of the lasers are turned off. This little push is just enough to loft the ball about a meter high through a microwave-filled cavity. Under the influence of gravity, the ball then falls back down through the microwave cavity.