We have an uncertain future continuously coming into existence relative to the instant absorption and emission of photon energy. The future is a blank canvas that we can interact with forming the possible into the actual. And the future we are dealing with is from our point of reference. The future is unfolding with each photonelectron interaction with the respective elements of the periodic table and the individual waves formed by the electromagnetic spectrum. It’s a process of energy exchange that forms reality. If we look at the quantum world, the ‘past’ is represented by anti-matter annihilation which maintains a balance between matter and anti-matter showing a balance between the future and the past. In the Delayed Choice Quantum Eraser Experiment, time is unfolding photon by photon within the experiment, within our frame of reference. But we have an infinite number of reference frames coming in and out of existence with a timeline for each object. What is our past might be the future to an observer from a different frame of reference. Everything is relative.
We have an uncertain future continuously coming into existence relative to the instant absorption and emission of photon energy. The future is a blank canvas that we can interact with forming the possible into the actual. And the future we are dealing with is from our point of reference. The future is unfolding with each photonelectron interaction with the respective elements of the periodic table and the individual waves formed by the electromagnetic spectrum. It’s a process of energy exchange that forms reality. If we look at the quantum world, the ‘past’ is represented by anti-matter annihilation which maintains a balance between matter and anti-matter showing a balance between the future and the past. In the Delayed Choice Quantum Eraser Experiment, time is unfolding photon by photon within the experiment, within our frame of reference. But we have an infinite number of reference frames coming in and out of existence with a timeline for each object. What is our past might be the future to an observer from a different frame of reference. Everything is relative.
The quantum eraser effect of Scully and Drühl dramatically underscores the difference between our classical conceptions of time and how quantum processes can unfold in time. Such eyebrow-raising features of time in quantum mechanics have been labeled "the fallacy of delayed choice and quantum eraser" on the one hand and described "as one of the most intriguing effects in quantum mechanics" on the other. In the present paper, we discuss how the availability or erasure of information generated in the past can affect how we interpret data in the present. The quantum eraser concept has been studied and extended in many different experiments and scenarios, for example, the entanglement quantum eraser, the kaon quantum eraser, and the use of quantum eraser entanglement to improve microscopic resolution.
Quantum physics has dramatically reshaped our understanding of time and reality, revealing that the present moment occupies a uniquely privileged position within physical processes. In the first paper ("Quantum Physics Prefers the Present: A Temporal Ontology Grounded in Measurement"), we saw how quantum phenomena such as wavefunction collapse and measurement highlight the “now” as the only time when possibilities become actual. However, simply embracing presentism – the doctrine that only the present exists – is not enough. Presentism’s traditional metaphysical stance, which conflates existence with reality by declaring all non-present things unreal, runs into serious conceptual roadblocks when confronted with quantum experiments and the demands of causality and truth over time. This second paper advocates Existential Realism (ER) as a more nuanced and robust ontological framework that builds on those quantum insights while overcoming presentism’s limitations. By rigorously distinguishing existence from reality, ER provides a richer account of quantum phenomena – one that honors the special role of the present without erasing the past or negating the future. We will argue that ER better captures the ontology implied by quantum mechanics, from delayed-choice experiments and collapse theories to decoherence, and that it empowers a view of time where “becoming” and temporal agency are coherent and defensible. In short, Existential Realism preserves the empirical centrality of the present while acknowledging the tangible reality of past causes and future possibilities — making it a more comprehensive fit for quantum reality.
Despite the obvious utility of the concept, it has often been argued that time does not exist. I take the opposite perspective: let's imagine that time does exist, and the universe is described by a quantum state obeying ordinary time-dependent quantum mechanics. Reconciling this simple picture with the known facts about our universe turns out to be a non-trivial task, but by taking it seriously we can infer deep facts about the fundamental nature of reality. The arrow of time finds a plausible explanation in a "Heraclitean universe," described by a quantum state eternally evolving in an infinite-dimensional Hilbert space.
The cover design is from a Greek bronze mirror, said to have come from Corinth, and is dated about 350-300 B.C.It shows Aphrodite and Pan playing fivestones.Originally a magical means for divining the future, the five-stones of this engraving is a game of chance.Its throws, like those of dice, are controlled by probabilistic laws.The behavior of elementary particles is also governed by probabilistic laws.As in the game of five-stones so in the world of particles, no event can be foretold as certain to happen, but only as likely to happen with a given degree of probability.The time of such a probabilistic universe is different from the time of ordinary human experience.It misses continuity, and nothing in its nature corresponds to our notions of now versus then, or to the related distinctions among future, past, and present.Aphrodite is seated on a stone slab next to Pan-the god of woods and pastures.Their bench is a sample of solid objects that are formed when elementary particles jell into massive matter.The universe of Newtonian physics comprises small as well as immense chunks of such matter.Events in that world are connected by deterministic rather than probabilistic laws, time is continuous, and a meaning may be assigned to the idea of well-defined instants.But it is still a universe without the kind of temporality that might be metaphorically described as flowing.The goose in front of the bench is a traditional attribute of Aphrodite-as are doves, swans, and dolphins.Let her small entourage represent the life process itself.It is the instant by instant internal coordination necessary for the maintenance of life that defines a now in the nowless world of inanimate matter.And, it is the biological needs of organisms that distinguish between future and past with reference to those present needs, and thereby identify a direction of time.The central figure is Aphrodite, the goddess of love, beauty, and fertility.According to Homer, "her enchantments came from this: allurement of the eyes, hunger of longing, and the touch of lips that steals all wisdom from the coolest men."Through her capacity to create designs for a long-term future and retain memories of a long-term past, the Aphrodite of this Arcadian image represents the complex time of the human mind.vii
Although it may seem The Delayed Choice experiments contradict causality and one could construct an experiment which could possibly affect the past, using Many World interpretation we prove it is not possible. We also find a mathematical background to Which-path information and show why its obtainability prevents system from interfering. We find a system which exhibit both interference and correlation and show why one-particle interference and correlations are complementary. Better visible interference pattern leads to worse correlations and vice versa. Then, using knowledge gained from Quantum Eraser and Delayed Choice experiments we prove there is not an objective reality in a sense of Einstein, Podolsky and Rosen. Furthermore, we discuss the difference between ``outer'' (non-interacting) and ``inner'' (interacting) observer. We find the mathematical relationship between the ``universal'' wave function used by ``outer'' observer and processes the ``inner'' observer sees, which is our small contribution to the measurement problem.
In quantum mechanics it is usual to represent physical reality as a vector in Hilbert space at a particular time, with evolution being governed by Schrodinger's equation which involves an externally imposed time parameter. This leads to difficulties if one wishes to regard the universe as a quantum mechanical system, because there should no time external to such a system. The approach in this paper is to represent the totality of reality as a vector in Hilbert space. The author shows how time evolution follows, where time now is defined in terms of the states of a quantum mechanical clock which is part of the system. Rather than the correlation between the clock states and the states of the rest of the system arising because both are governed by an imposed law involving an external time parameter, it is seen that this correlation is of the separation-independent Einstein-Podolsky-Rosen type. The total reality vector, which incorporates the whole history of the system, is shown to be a zero-energy eigenstate of the system Hamiltonian. He discusses systems of finite and infinite lifetime, and is able to answer the question: what was the state before the initial state? He concludes that the quantum mechanical system of this paper is a reasonable representation of the observed universe.