Have you ever wondered why there is so much matter in the universe but less evidence of antimatter? In theory, for every atom of matter there should be one atom of antimatter. The trouble starts if matter and antimatter come in contact.
Dr. Egon Spengler: There's something very important I forgot to tell you.
Dr. Peter Venkman: What?
Dr. Egon Spengler: Don't cross the streams.
Dr. Peter Venkman: Why?
Dr. Egon Spengler: It would be bad.
Dr. Peter Venkman: I'm fuzzy on the whole good/bad thing. What do you mean, "bad"?
Dr. Egon Spengler: Try to imagine all life as you know it stopping instantaneously and every molecule in your body exploding at the speed of light.
Dr Ray Stantz: Total protonic reversal.
Dr. Peter Venkman: Right. That's bad. Okay. All right. Important safety tip. Thanks, Egon
- Ghostbusters (1984)
Matter plus antimatter equals huge explosion, human sacrifice, dogs and cats living together... mass hysteria.
The imbalance of matter and antimatter is known in particle physics as a CP violation. CP is the product of two symmetries: C for charge conjugation, which transforms a particle into its antiparticle, and P for parity, which creates the mirror image of a physical system. Simply speaking, charge conjugation is a simple symmetry between particles and antiparticles. The idea behind parity symmetry is that the equations of particle physics don’t vary if a reverse reaction occurs. This leads to the prediction that the mirror image of a reaction (such as a chemical reaction or radioactive decay) occurs at the same rate as the original reaction. If there is one atom of matter there is a corresponding atom of antimatter. If there is a reaction that changes matter to antimatter at a certain rate, then the reverse reaction – changing antimatter to matter – should occur at the same rate.
That rule is violated if there is more matter than antimatter. (a CP violation)
An article in New Scientist examines a promising new theory on the matter-antimatter imbalance. Scientist working with the Tevatron particle accelerator at Fermilab in Batavia, Illinois have been studying several properties of Bs mesons and their oscillations by picking through the debris created when protons and antiprotons collide. Particle physicists have long thought that they might find such evidence in a particle called the Bs meson, which comprises a bottom antiquark bound to a strange quark. The Bs is one of a handful of mesons that transforms into its own antiparticle and back again 3 trillion times per second before decaying into other particles (see Diagram).
These oscillations between matter and antimatter make it a good place to look for evidence that CP violation goes beyond the standard model. They noted clear evidence of CP violation, resulting in more protons than antiprotons.
Luca Silvestrini, nuclear physicist, believes that this is new physics at work in the oscillations. His group cannot yet say what kind of new physics - that will require others to test whether existing theories explain the data. "It is tantalizingly interesting at the moment," says Val Gibson, an expert on B meson physics at the University of Cambridge. "If it is true, it is earth-shattering."
Why do I think this is important? This has implications for faster than light travel. Last year physicist Richard Obousy proposed that faster than light travel - warp speed (as in Star Trek) - could be achieved by directly manipulating the extra dimensions of string theory.
Science fiction writers, particularly those who were writing for Star Trek (original series) picked up on the idea of warp drive, faster than light travel, and matter-antimatter reactions, from the work of physicists including Dr. Andrei Sakharov who were looking at baryon and antibaryon particles, gravitons, relativity, and some of the Grand Unification Theories.
The physics behind warp drive started to take shape beginning in the mid 1960s but it was not until 1994 that Dr. Miguel Alcubierre developed a plausible method to make it happen. He proposed a method of stretching space in a wave which would in theory cause the fabric of space ahead of a spacecraft to contract and the space behind it to expand. The ship would ride this wave inside a region known as a warp bubble of flat space. Anyone on the ship will perceive time as proceeding at its normal pace, while the warp bubble is being pulled forward by the contraction of spacetime in front of the bubble.
Obousy in turn suggests that superstrings wrap around the extra dimensions keeping them compact, and that manipulating the strings will cause and adjustment in the size of the extra dimension, allowing a controlled expansion and contraction of the space surrounding an interstellar craft.
The warp bubble in which the interstellar craft rides would be created by a controlled imbalance of matter-antimatter.
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