Most scientists believe the universe began from a “singularity,” an impossible-to-imagine point, which they think contained everything that there is in the universe -- matter, energy, and even time and space -- exploded with an enormous rush. Scientists don’t know what caused this point to explode in a “Big Bang” about 15 billion years ago, and they don’t know what -- if anything – existed before the bang occurred, or even if there was a “before” before it happened. So-called “black holes” are believed to be similar to this singularity except that they contain far less of the universe. Black holes are believed to be collapsed stars of such density and gravitational strength that once caught; nothing – not even light – can escape their pull. Scientists believe that as the Big Bang exploded outward in a blaze of energy, the universe was blown up like a child blows up a balloon.