An "anti-universe" could explain all those cosmological mysteries at once! 🌟

The Universe seems simpler than what current theories imagine. Recent observations, from vast cosmic expanses to the tiniest particles, have not revealed the complexity scientists expected. This finding challenges the major models of modern cosmology, such as string theory and cosmic inflation.


For decades, string theory has suggested that the Universe is composed of tiny vibrating loops of matter. But to work, it introduces extra spatial dimensions that are invisible and folded in on themselves. Inflation, on the other hand, proposes that the Universe experienced a sudden, vast expansion right after the Big Bang, explaining why it appears so uniform. However, despite their theoretical strengths, neither hypothesis has received concrete proof so far.

The predictions of inflation, particularly gravitational waves with very long wavelengths, have yet to be observed. Several models of inflation have even been ruled out by current measurements. This gap between theory and reality is pushing some researchers to explore other avenues.

Two physicists, including Latham Boyle, propose a simple and bold alternative: a symmetrical Universe where the Big Bang created a "time-reversed reflection". In their "mirror" hypothesis, the Universe would be accompanied by an anti-universe, evolving in the opposite direction in time, while respecting a symmetry called CPT, a principle that balances matter and antimatter in both time and space.

This "mirror" model could explain several riddles of modern cosmology. It could, for instance, provide an elegant solution to the dark matter enigma: hypothetical particles called "right-handed" neutrinos, invisible except through their gravitational influence, could comprise this matter. And this hypothesis is testable: if it's correct, one of the three known types of neutrinos should be massless, a property currently under investigation by scientists.

The researchers have also looked into the question of entropy, a concept related to the Universe's organization. According to them, a simple, flat, and expanding Universe, like the one we observe, would be the most probable and stable state. This approach, based on probabilistic calculations, could explain why our Universe is so uniform without needing to invoke inflation.

Even better, quantum fluctuations in this "mirror" Universe would be enough to explain the formation of observed structures, like galaxies, without generating those gravitational waves that have so far gone undetected.

This alternative theory still needs refining, but it offers a refreshing and more intuitive view of the Universe. The researchers encourage the scientific community to consider these new, less complex perspectives to move forward in understanding the Universe. By returning to observations rather than relying on sophisticated mathematical models, the mysteries of the Universe may, in fact, be more accessible than previously thought.