Expanding Universe, Dark Energy Are Illusions
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What’s the Latest Development?
A new theory pioneered by cosmologist Christos Tsagas claims that some of the most confounding observations and theories in modern physics, specifically that of an expanding universe caused by slippery dark energy, may be just an illusion created by the location of our corner of the cosmos relative to other parts. The explanation hinges on an observation known as ‘dark flow’ which states that our section of the universe, roughly 2.5 billion light years wide, is moving at a different speed and direction than other sections.
What’s the Big Idea?
If ‘dark flow’ is real, it may provide a simpler understanding of the cosmos than current theories. When an expanding universe was observed in the 1920s, cosmologists were confounded because gravity implies that large bodies attract one another—scientists therefore thought the universe was naturally shrinking. “Dark flow is by far less mysterious [than dark energy]: While no one knows what dark energy is, or how we might find it, dark flow is merely movement.” The theory also throws into question how, or if, the universe will end.