According to the Big Bang theory, why do we live in a universe that is made of almost entirely of matter rather than antimatter?
A) During the first 0.001 second after the Big Bang, particles and antiparticles were made in almost but not perfectly equal numbers. Everything annihilated except the very slight excess of matter particles.
B) GUT theories predict that under the conditions that prevailed in the early universe, the normal laws of physics would have been suspended so that only matter particles were created, and no particles of antimatter.
C) Einstein's famous equation E = mc2 tells us that energy can turn into matter, but does not tell us that it can turn into antimatter.
D) The fact that we live in a universe made of matter is not surprising, because antimatter has never been shown to exist for real.
Question 2
A star is seen to have two transiting planets. Planet 1 transits every 3 months, and Planet 2 transits every 15 months. What can we infer about their orbits?
A) Planet 2's semimajor axis is larger than Planet 1's.
B) Planet 1's orbit is more eccentric than Planet 2's.
C) Planet 2's orbit is more eccentric than Planet 1's.
D) Planet 1's semimajor axis is larger than Planet 2's.
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