29: The Big Bang Flashcards
idea that physical laws must be the way they are because otherwise we could not be here to measure them
anthropic principle
the theory of cosmology in which the expansion of the universe began with a primeval explosion (of space, time, matter, and energy)
Big Bang
a model in which the universe expands from a Big Bang, stops, and then contracts to a big crunch
closed universe
microwave radiation coming from all directions that is the redshifted afterglow of the Big Bang
cosmic microwave background (CMB)
the term in the equations of general relativity that represents a repulsive force in the universe
cosmological constant
the term in the equations of general relativity that represents a repulsive force in the universe
cosmology
in cosmology, the density that is just sufficient to bring the expansion of the universe to a stop after infinite time
critical density
a model of the universe that has a critical density and in which the geometry of the universe is flat, like a sheet of paper
flat universe
the building of heavier atomic nuclei from lighter ones
fusion
physical theories that attempt to describe the four forces of nature as different manifestations of a single force
grand unified theories (GUTs)
a theory of cosmology in which the universe is assumed to have undergone a phase of very rapid expansion when the universe was about 10–35 second old; after this period of rapid expansion,
identical to standard Big Bang
inflationary universe
the third element in the periodic table - ___ nuclei with three protons and four neutrons were manufactured during the first few minutes of the expansion of the universe
lithium
the speculative idea that our universe is just one of many universes, each with its own set of physical laws
multiverse
a model in which the density of the universe is not high enough to bring the expansion of the universe to a halt
open universe
when radiation began to stream freely through the universe without interacting with matter
photon decoupling time
