Why did the big bang happen
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Why Did the Big Bang Happen?
The origin of the universe, commonly attributed to the Big Bang, is a topic of significant scientific inquiry and debate. Various theories attempt to explain why and how this monumental event occurred. Here, we explore several perspectives based on recent research.
Traditional Big Bang Theory
The traditional Big Bang theory posits that the universe originated from a single, cataclysmic explosion approximately 10 to 20 billion years ago. This theory has become the cornerstone of modern cosmology, explaining the expansion of the universe and the distribution of galaxies. However, some researchers argue that the universe is too vast to have originated from a single explosion, suggesting instead that it is a plasma universe growing slowly in giant strands across space1.
The Ekpyrotic Universe: Colliding Branes
An alternative to the traditional Big Bang theory is the Ekpyrotic universe model. This theory proposes that the hot Big Bang was the result of a collision between a brane in the bulk space and a bounding orbifold plane. This collision transformed an otherwise cold, static universe into the hot, dynamic one we observe today. The Ekpyrotic model addresses several cosmological issues, such as the horizon, flatness, and monopole problems, without relying on the concept of inflation. Instead, it utilizes phenomena from theories involving extra dimensions and branes, predicting a unique gravitational wave spectrum that could be tested by future experiments2.
The Dark Big Bang: A Second Phase Transition
Another intriguing hypothesis is the concept of a "Dark Big Bang," which suggests that dark matter and possibly dark radiation were formed through a phase transition in the dark sector. This event, occurring after the traditional Big Bang, transformed dark vacuum energy into a hot dark plasma of particles. The Dark Big Bang could explain the correct abundance of dark matter through mechanisms like dark matter cannibalism or pair-annihilation, followed by thermal freeze-out. This theory also predicts distinctive gravitational wave signatures, which could be detected by pulsar timing array experiments, offering a new avenue for understanding the universe's early conditions3.
Conclusion
The question of why the Big Bang happened remains a complex and multifaceted topic. While the traditional Big Bang theory provides a foundational framework, alternative models like the Ekpyrotic universe and the Dark Big Bang offer compelling explanations that address some of the limitations of the conventional view. Ongoing research and future experimental evidence will continue to shape our understanding of this profound cosmic event.
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Most relevant research papers on this topic
THE BIG BANG NEVER HAPPENED
The big bang theory is challenged by a plasma universe, which is too large to have been created from a single explosion 20 billion years ago, and instead grows slowly in giant strands connecting the smallest particles of matter to an infinity of different cosmic systems.
Highly CitedThe Ekpyrotic universe: Colliding branes and the origin of the hot big bang
The hot big bang universe is produced by the collision of a brane with a bounding orbifold plane, addressing cosmological horizon, flatness, and monopole problems without invoking superluminal expansion.
Highly CitedDark matter and gravitational waves from a dark big bang
The Dark Big Bang scenario, which creates dark matter and potentially dark radiation, is consistent with structure formation and the CMB constraints, and may lead to striking gravity wave signatures.
Quantum nature of the big bang.
The big bang is replaced by a big bounce in homogeneous isotropic models with a scalar field, allowing for a detailed realization of the "emergent time" idea and ensuring deterministic quantum evolution across the deep Planck regime.
Highly CitedMisconceptions about the big bang.
The big bang theory is based on the expansion of space, not an explosion in space, and the universe does not expand at a single speed.
Naming the Big Bang
The name Big Bang has a richer and more surprising history than commonly assumed, and its etymological approach provides insights into the historical understanding of the emergence of modern cosmology.
Theism, Atheism, and Big Bang Cosmology.
The Big Bang cosmology supports either theism or atheism, with William Lane Craig arguing for the Big Bang being created by God and Quentin Smith arguing against it.
Highly CitedWhat happened before the Big Bang
The precise state of the Universe before the Big Bang remains unanswered, requiring assumptions and prejudices for understanding its pre-Big Bang state.
Highly CitedEnd for the Big Bang Theory, Dark Matter and Dark Energy. A New Logical, Clear and Scientific Explanation for the Accelerating Expansion of the Universe
The theory of the chain reaction explains the accelerated expansion of the universe, providing a clear and scientific explanation for the creation and operation of the Cosmos.
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