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EEE / The God Particle: Part IV
« on: November 14, 2016, 08:15:48 PM »
The standard model can’t explain several towering mysteries about the universe that have their roots in the minuscule world of particles and forces. If there’s one truly extraordinary concept to emerge from the past century of inquiry, it’s that the cosmos we see was once smaller than an atom. This is why particle physicists talk about cosmology and cosmologists talk about particle physics: Our existence, our entire universe, emerged from things that happened at the smallest imaginable scale. The big bang theory tells us that the known universe once had no dimensions at all—no up or down, no left or right, no passage of time, and laws of physics beyond our vision.
How does an infinitely dense universe become a vast and spacious one? And how is it filled with matter? In theory, as the early universe expanded, energy should have condensed into equal amounts of matter and antimatter, which would then have annihilated each other on contact, reverting to pure energy. On paper, the universe should be empty. But it’s full of stars and planets and charming French villages and so on. The LHC experiments may help physicists understand our good fortune to be in a universe that grew with just enough more matter than antimatter.
What about the riddle of dark matter? Scrutiny of the motion of distant galaxies indicates that they are subject to more gravity than their visible matter could possibly account for. There must be some exotic hidden matter in the mix. A theory called supersymmetry could account for this: It states that every fundamental particle had a much more massive counterpart in the early universe. The electron might have had a hefty partner that physicists refer to as the selectron. The muon might have had the smuon. The quark might have had ... the squark. Many of those supersymmetric partners would have been unstable, but one kind may have been just stable enough to survive since the dawn of time. And those particles might, at this very second, be streaming through your body without interacting with your meat and bones. They might be dark matter.
How does an infinitely dense universe become a vast and spacious one? And how is it filled with matter? In theory, as the early universe expanded, energy should have condensed into equal amounts of matter and antimatter, which would then have annihilated each other on contact, reverting to pure energy. On paper, the universe should be empty. But it’s full of stars and planets and charming French villages and so on. The LHC experiments may help physicists understand our good fortune to be in a universe that grew with just enough more matter than antimatter.
What about the riddle of dark matter? Scrutiny of the motion of distant galaxies indicates that they are subject to more gravity than their visible matter could possibly account for. There must be some exotic hidden matter in the mix. A theory called supersymmetry could account for this: It states that every fundamental particle had a much more massive counterpart in the early universe. The electron might have had a hefty partner that physicists refer to as the selectron. The muon might have had the smuon. The quark might have had ... the squark. Many of those supersymmetric partners would have been unstable, but one kind may have been just stable enough to survive since the dawn of time. And those particles might, at this very second, be streaming through your body without interacting with your meat and bones. They might be dark matter.