Our universe could be the mirror image of an antimatter universe extending backwards in time before the Big Bang. Physicists, who have devised a new cosmological model positing the existence of an “antiuniverse” which, paired to our own, preserves a fundamental rule of physics called CPT symmetry.

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Our universe could be the mirror image of an antimatter universe extending backwards in time before the Big Bang. Physicists, who have devised a new cosmological model positing the existence of an “antiuniverse” which, paired to our own, preserves a fundamental rule of physics called CPT symmetry.