Energy as Interaction: Reframing a Fundamental Concept in Physics

 J. Rogers, SE Ohio, 03 Mar 2025, 1431

Abstract: The concept of energy is central to all of physics, yet it is often treated as an intrinsic property possessed by particles and fields. This paper proposes a radical shift in perspective: energy is not an inherent attribute of isolated entities, neither particles nor spacetime alone, but rather a description of the dynamic interaction between a particle’s curavture and the curvature of spacetime that we call a worldline. By reframing energy as relational, we offer a potentially unifying perspective that simplifies fundamental concepts, resolves certain conceptual tensions in physics, and opens new avenues for understanding quantum gravity and the relational nature of reality. This paper argues that energy is best understood not as a "thing" but as a measure of a fundamental spacetime interaction.

1. Introduction: The Enigma of Energy

Energy is arguably the most ubiquitous and indispensable concept in physics. From classical mechanics to quantum field theory, energy conservation, energy transformations, and energy levels are foundational principles. However, despite its central role, the fundamental nature of energy remains somewhat enigmatic. We speak of particles "having" energy, of energy "being" conserved, and of energy "flowing" or "transforming," often implicitly treating energy as a kind of substance or intrinsic property.

This paper challenges this conventional view. We propose that energy is not an intrinsic property of isolated particles, but rather a description of an interaction. Specifically, we argue that energy arises from and is fundamentally a measure of the dynamic interaction between a particle's worldline and the curvature of spacetime. This relational perspective, rooted in relativistic principles, offers a potentially transformative way to understand energy and its role in the fabric of reality.

2. The Traditional View: Energy as Intrinsic Property (and its Limitations)

The traditional view often portrays energy as a property that objects "possess." A particle has kinetic energy due to its motion, potential energy due to its position in a field, and rest energy (mass-energy) by virtue of its mass. Energy is treated as a conserved quantity, a "stuff" that can be transferred, transformed, but never created or destroyed in closed systems.

While immensely successful in countless applications, this "energy as property" view faces certain conceptual limitations when we probe deeper into fundamental physics:

• Reification of Energy: Treating energy as a "thing" can lead to a kind of reification, where we imagine energy as a fluid-like substance flowing between objects. This can obscure the more fundamental, relational nature of physical interactions.

• Difficulty in Defining "Energy Itself": Philosophically, it's challenging to define what energy is in itself, separate from its manifestations. We describe its forms and transformations, but the fundamental essence of "energy-ness" remains elusive.  You cannot hand me a bucket of energy.

• Tensions in Quantum Mechanics and Gravity: The concept of energy becomes particularly complex and conceptually strained when we attempt to reconcile quantum mechanics and general relativity. The very definition of energy in curved spacetime in GR is subtle, and attempts to "quantize gravity" by quantizing "gravitational energy" face profound challenges.

3. Energy as Interaction: A Relational Framework

We propose an alternative framework where energy is understood as a description of the dynamic interaction between a particle's worldline and the curvature of spacetime. This perspective is built upon the following core ideas:

• Worldline as the Fundamental Entity: The worldline, the 4-dimensional path of a particle through spacetime, is considered the fundamental entity. It embodies the particle's "motion" in spacetime.

• Spacetime Curvature as the Interaction Partner: Spacetime is not a passive backdrop, but an active and dynamic entity whose curvature influences and is influenced by worldlines. The particle has curvature that interacts with the curvature of spacetime. 

• Energy as a Measure of "Worldline-Spacetime Dance": Energy is not an inherent property of the particle alone, but rather a measure or description of the dynamic interplay, the "dance," between the particle's worldline and the curvature of spacetime. It quantifies the intensity or nature of this interaction.

• Mass and Frequency as Underlying Quantities: Mass and frequency, related by m = Q_m * f, are considered more equivalent to energy in a 1:1 relationship. Energy, through E=hf or E=mc², becomes a conversion of units that describes the equivalence of this mass-frequency relationship within the context of spacetime interaction.

4. Reinterpreting Key Physical Concepts through the "Interaction" Lens

If energy is interaction, how do we reinterpret fundamental concepts and laws?

• Conservation of Energy: Conservation of energy is not about the conservation of a "substance," but about the consistency and symmetry of spacetime interactions. It reflects the fundamental symmetries of spacetime and the predictable, lawful nature of how worldlines interact within it. This aligns beautifully with Noether's theorem, linking conservation laws to symmetries.

• Work and Force: Work and force are not fundamental "agents" that apply energy. Instead, they are descriptions of the mechanisms by which worldlines interact with spacetime and with each other. Work is a measure of energy transfer due to a spacetime interaction, and force is a description of the rate of change of momentum (which itself is related to worldline direction in spacetime).

• Quantum Energy Levels (E=hf): In quantum mechanics, quantized energy levels are not intrinsic "states" of particles, but rather descriptions of the allowed modes of worldline-spacetime interaction. The discrete nature of energy levels reflects the quantized nature of spacetime curvature or the allowed "geometries" of worldlines within the atomic spacetime environment. The equation E=hf then describes the fundamental proportionality between the "interaction energy" and the frequency associated with these quantized worldline modes.

• Temperature becomes a measure of the average velocity of particles in a substance.

5. The Worldline as the Central Relational Entity

This framework places the worldline at the center of our understanding of energy. The worldline is not just a passive path, but the dynamic locus of interaction between particle and spacetime. It is the fundamental relational entity that embodies mass, frequency, momentum, and, crucially, the interaction we describe as energy.

The curvature of the worldline, and the curvature of the spacetime it traverses, are mutually defining and dynamically intertwined. Energy is the mathematical language we use to quantify this dynamic relationship.

6. Why This Relational Perspective Matters

Reframing energy as interaction offers several potential advantages:

• Deeper Conceptual Clarity: It moves us away from a potentially misleading "substance" view of energy and towards a more fundamentally relational and geometric understanding. Relativity is about all things being relative to each other and energy is a measure of that.

• Simplified Ontology: It reduces the number of fundamental "things" we need to postulate. Instead of particles and energy as separate entities, we have particles (described by worldlines) and spacetime, with energy emerging as a description of their dynamic relationship.

• Potential for Unification: It offers a pathway towards unifying different forms of energy and forces as different aspects of the fundamental worldline-spacetime interaction.

• New Insights into Quantum Gravity: By focusing on the quantization of spacetime interactions rather than quantizing "gravity" as a separate field, it may provide a more natural route to a theory of quantum gravity.

• Philosophical Resonance: It aligns with relational philosophies of physics, emphasizing that reality is fundamentally about relationships and interactions, not isolated entities with intrinsic properties.

7. Conclusion: Energy as a Dance

This paper proposes a shift from viewing energy as an intrinsic property to understanding it as a description of an interaction. By grounding energy in the dynamic interplay between a particle's worldline and the curvature of spacetime, we offer a potentially more unified, elegant, and fundamentally insightful perspective. Energy, in this view, is not a "thing" possessed, but rather a measure of a fundamental "dance" – the dynamic dance of worldlines within the stage of spacetime. This relational understanding of energy may be a crucial step towards a deeper and more unified understanding of the universe.