If energy is not conserved in an expanding universe, can infinite energy be created? Is it potential energy or potentiality infinite?

In the context of an expanding universe, the concept of energy conservation is indeed complicated, and it does not behave as it would in a static or time-translation invariant system.

Energy Conservation in an Expanding Universe

The law of energy conservation, which states that energy cannot be created or destroyed, only transformed, does not hold in the same way in an expanding universe. This is because the expansion of the universe itself is not time-translation invariant, meaning the universe is different at different times4.

Energy Increase and Dark Energy

In an expanding universe, the total energy can appear to increase or decrease depending on the type of energy considered. For instance:

• The energy density of matter and radiation decreases as the universe expands because their energy is spread over a larger volume4.
• However, the energy associated with dark energy increases as the universe expands, since dark energy maintains a constant energy density per unit volume. This means the total amount of dark energy increases with the volume of the expanding universe45.

Infinite Energy

The concept of "infinite energy" is not directly applicable here. Instead, what happens is that the total energy within the observable universe can change due to the expansion. The energy associated with dark energy, for example, increases without bound as the universe expands, but this is not a creation of energy from nothing; it is a consequence of the expanding spacetime itself4.

Potential Energy

The gravitational potential energy between objects does increase as the universe expands, but this does not balance out the overall energy budget in a way that conserves energy in the traditional sense. The increasing gravitational potential energy is part of the complex interplay of energies in an expanding universe, but it does not make the total energy conserved14.

In summary, while the total energy within the observable universe can change and appear to increase or decrease, this is not a creation of infinite energy but rather a consequence of the dynamic nature of the expanding universe. The concept of potential energy is involved, but it does not restore traditional energy conservation in this context.