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The bubble universe theory, also known as the bubble universe theory or spacetime bubble theory, is a hypothesis in theoretical physics that suggests that our universe could be just one of many "bubbles" or separate regions in a multiverse.
According to this theory, each of these bubbles would be a universe with its own physical laws and properties, and would be separated from each other by vast distances in extra dimensional space.
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These bubbles could have formed during an event known as cosmic inflation, a rapid expansion of the early universe.
However, it is important to note that the bubble universe theory is still a speculative idea and has no solid empirical evidence to support it.
It is part of a constantly developing and debated field of study in theoretical physics.
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