Well believe it or not, time machines do exist -- they're called telescopes. Astronomers who peer through them see stars and galaxies not as they are now, but as they appeared when the starlight began its journey. Through telescopes, astronomers can 'travel' billions of years into the past.
Astronomer Richard Ellis of the California Institute of Technology recently used NASA's Hubble Space Telescope to travel backwards nearly to the time of the Big Bang itself. He and his colleagues went in search of newborn stars -- the first ones to appear in our Universe. Ellis explains: 'At some point a billion or so years after the Big Bang, gravitational attraction caused the gas that filled the Universe to collapse and form the first stars. Searching for signs of those stars, which we call First Light, is one of the most interesting challenges in modern astronomy.
'As far as the laws of mathematics refer to reality, they are not certain; and as far as they are certain, they do not refer to reality.'