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Suppose there’s a scalar field that permeates the universe.
Do quantum fluctuations really cause the field value ϕ to fluctuate, making the field value higher at some points in space and lower at some other points in space?
Some scientists argued that the quantum field is not fluctuating. The value of a field at a point is not precisely determined but it has nothing to do with fluctuations. $~$While some states that the value of a field at a point in space is constantly fluctuating.