Existence and reality are distinct realms. Existence, being the larger realm, houses reality, the smaller realm. The two realms overlap in terms of the raw physics of existence. Reality is the transformation of existence space, characterized by computable causation space with its interactions, measurements and results, into meaning space, characterized by the perishability/survivability axis of living organisms.

One of the essentials of meaning is consequence. It separates reality from existence as expressed by the difference between a change that can transformation, amplify, diminish or destroy and a change that merely terminates in an indifferent result. The absence or presence of life determines whether causation has consequences forward directed, or merely results indifferent.

On a planet sans living organisms there's a boulder atop a hill. The planet has atmosphere, so a strong wind pushes against the boulder and sets it into motion rolling down the hill. Eventually, the boulder reaches the bottom of the hill and finally comes to rest on level ground. The resting place of the boulder is a result. Imagine now another example of the same hill and gust of strong wind with the boulder rolling down the hill and smashing together with a moving car when they intersect. It's all the same logic and causation making the boulder roll down the hill. The big however is fact that driver of the car gets killed by the impact. That's not a result. That's a consequence with forward direction in memory and behavior of affected sentients. Cops show up; likewise ambulance, eventually next of kin and finally the hearse. The driver's young children won't be seeing father tonight, or any other night.

In general, I'm saying reality is an interpretation of physics by living organisms. The label for the
interpretation is reality. Physical things exist. Living organisms and their experiences vis-á-vis physics are real. Reality is therefore a scalable meaning space numerator defined in terms of its denominator, survivability/perishability.

Throughput in the reality of sentient-mediated space is change that impacts identity as transformation, amplification, loss or destruction. This type of change in reference to sentient identity persistence coalesces as meaning.