Why Does the Universe Expand and this Gets Quantum - Science

If space and time are fluctuating, why can’t we feel it?

Credit: NASA


From University of British Columbia, they have asked one of the Greatest of the Why is their Air questions ... and might they have answered it.

UBC physicists may have solved one of nature's great puzzles: what causes the accelerating expansion of our universe?

PhD student Qingdi Wang has tackled this question in a new study that tries to resolve a major incompatibility issue between two of the most successful theories that explain how our universe works: quantum mechanics and Einstein's theory of general relativity.

Science Daily:  Solving one of nature's great puzzles: What drives the accelerating expansion of the universe?


First they answer why the Universe does not explode or hasn't yet.

"Space-time is not as static as it appears, it's constantly moving," said Wang.

"This is a new idea in a field where there hasn't been a lot of new ideas that try to address this issue," said Bill Unruh, a physics and astronomy professor who supervised Wang's work.

In 1998, astronomers found that our universe is expanding at an ever-increasing rate, implying that space is not empty and is instead filled with dark energy that pushes matter away.

The most natural candidate for dark energy is vacuum energy. When physicists apply the theory of quantum mechanics to vacuum energy, it predicts that there would be an incredibly large density of vacuum energy, far more than the total energy of all the particles in the universe. If this is true, Einstein's theory of general relativity suggests that the energy would have a strong gravitational effect and most physicists think this would cause the universe to explode.

- SD

Ed:  bummer, man; bummer


Here's the Sherlock Holmes part.

Unlike other scientists who have tried to modify the theories of quantum mechanics or general relativity to resolve the issue, Wang and his colleagues Unruh and Zhen Zhu, also a UBC PhD student, suggest a different approach. They take the large density of vacuum energy predicted by quantum mechanics seriously and find that there is important information about vacuum energy that was missing in previous calculations.

- SD


And the result.

Their calculations provide a completely different physical picture of the universe. In this new picture, the space we live in is fluctuating wildly. At each point, it oscillates between expansion and contraction. As it swings back and forth, the two almost cancel each other but a very small net effect drives the universe to expand slowly at an accelerating rate.

- SD

The entire Universe oscillates ... no reason to assail the scope of the kid's research.


As to why don't we feel it, they do answer the question and that's presented as the punchline but the Rockhouse thinks they already delivered the major punchline with discovery of the effect and how it works.

The interested student is invited ...