New model suggests partner anti-universe could explain accelerated expansion without the need for dark energy

The accelerated expansion of the current universe, believed to be driven by a mysterious dark energy, is one of the greatest puzzles in our understanding of the cosmos. The standard model of cosmology, called Lambda-CDM, explains this expansion as a cosmological constant in Einstein’s field equations. However, the cosmological constant itself lacks a full theoretical understanding, especially regarding its very small positive value.

To explain the accelerated expansion, physicists have proposed alternative explanations such as quintessence and modified theories of gravity, including scalar-tensor-vector gravity. Furthermore, explanations outside four dimensions, such as the braneworld scenarios in the Dvali-Gabadadze-Porrati (DGP) model, modify gravity at large distances due to the effect of higher-dimensional bulk on our four-dimensional brane, and variable brane tension.

My new model

In my work I propose another model to explain the current accelerated expansion of the universe. Unlike existing models, this does not require any form of dark energy or modified gravity approximations. However, there is a price to pay: we need an anti-universe partner whose timestream is oppositely related to our universe.

There are strong arguments supporting this concept. From the perspective of quantum theory, it is normal that the universe is created in pairs. Recently, Boyle et al. proposed that the universe does not spontaneously violate CPT (Charge, Parity, and Time reversal symmetry), but rather that the universe after the Big Bang is rather the CPT image of the universe before it, pointing to a partner opposing the big bang occurs. universe.

Recent results

In a recent article published in Gravity and cosmologyI used key concepts from quantum theory, such as relative entropy, and from general relativity, such as the zero energy state, which corresponds to the positive energy state. My findings suggest that the universe is expanding naturally at an accelerated rate.

Relative entropy, which in this case requires two states, corresponds to the universe and its partner anti-universe. Accelerated expansion seems inevitable in a universe created in pairs and respecting the zero energy state. This result is quite surprising, and readers familiar with Hawking’s area theorem may notice some similarities. The area theorem also concerns causal horizons and requires that the zero energy condition be preserved.

In our model, the causal horizon corresponds to the Big Bang. The results also apply to the partner’s anti-universe.

In short, the accelerated expansion of the universe is a challenging topic that continues to drive scientific efforts. Building on existing theories, my model provides an explanation using standard concepts from quantum theory and general relativity, without the need for elusive dark energy.

The results indicate that accelerated expansion is normal for a universe created in pairs. Furthermore, studying causal horizons can deepen our understanding of the universe. The beauty of this idea lies in its simplicity and naturalness, which sets it apart from existing explanations.

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