Central to the question of the age of the Universe are two important theoretical terms. The Hubble Constant refers to how fast the velocities of the galaxies increase with their distance from the Earth. There is quite a raging debate on the value of this constant ranging from 50 Km/sec per Mpc (Mpc is a Megaparsec, about 3 million light years) to 100 Km/sec per Mpc. This explains the disparity in the x 5 billion year estimate for the age of the universe. The other constant of importance is known as q that defines the deceleration of the
expansion of the universe. Depending on the critical density of the universe that this q constant is based, the universe will prove to be either infinitely expanding as in the flat and open models, or an oscillating closed universe; a big crunch/big bang universe that will ultimately condense back into a singularity and begin the process all over again(Weinberg). Hubble’s succesor Allan Sandage predicted a closed
universe when he plotted a number of radio galaxies many billions of light years away. The evidence for this closed universe was quickly challanged a few years later and eventually fell out of favor. To this day the Hubble Constant and the q constant remain the two most important unanswered problems in modern cosmology.
Observations have also supported the predictions of theorists that certain elements could only have been created moments after the big bang. Based on the relationship between the amount of helium in the universe and the number of different types of particle “families” researchers concluded that there is one neutrino per family of particles. Due to the current energy density of the universe there will be a corresponding amount of helium produced. This in turn will create different types of neutrinos. When the predicted amount of neutrinos corresponded to what was observed it was another victory for the big bang cosmology(Wald).
After the discovery of the cosmic background radiation in 1965 scientists were eager to extend their research into outerspace through the use of a man-made satellite orbiting the Earth. From this vantage point an unimpeaded opportunity to study this phenomenon would be made available and by late 1989 the Cosmic Background Explorer
(COBE) was ready for action. COBE consisted of three seperate
experiments. The first instrument was known as the FIRAS, an acronym for the Far Infrared Absolute Spectrometer. This instrument was
created to confirm the research previously accumulated that the background radiation does indeed have a black body spectrum
(Hoverstein).
The next question COBE attempted to answer was, is the background radiation the same temperature in all directions? Big bang theory states that in order to have mass condense and form galaxies, there must be inhomogeneties left over from the Big bang that will be able to be detectable. The differential microwave radiometer (DMR) was designed to detect anisotropy fluctuations on the scale of 30 millionths of a degree. Inflation theory predicted such fluctuations and that quantum processes at work during the primordial stages of the big bang (when the universe was the size of a proton) allowed for clouds of matter to condense into galaxies (Sawyer).
The final experiment was known as DIRBE. The Differential Infrared Background Experiment was designed to look into the farthest
corners of the Universe; upwards of 15 billion light years away from the Earth, and accumulate data on the infrared light of these
primordial galaxies. DIRBE data is continuing to be accumulated with no conclusions having been drawn to date (Gribbin). John Mather
from the University of California at Berkeley was responsible for the FIRAS experiment. Not long after COBE was positioned into orbit
came the exciting data that was eagerly awaited and much anticipated. The background radiation fit the blackbody curve to within 1%.
Sixty-seven seperate points of frequency obtained by COBE fir the theoretical blackbody spectrum perfectly! Observation had accurately
confirmed what Big bang cosmology had long ago predicted. This finding proved to be the easy part (Parker).
George Smoot and his colleagues also from Cal Berkeley took three arduous years to sort through the billions of bits of data that the DMR provided. His announcement on the 23rd of April, 1992 at the annual meeting of the American Physical Society in Washington,D.C. said it best: “English dosen’t have enough superlatives…to convey the story [of the results] , we have observed…15 billion year old
fossils that we think were created at the birth of the universe.”(Parker). Although the temperature fluctuations were less than thirty millionths of a degree in variation, these areas of temperature and density fluctuation were more than 500 million light years in width. These miniscule perbutations that were formed during the big bang were the very density that was needed in order to create galaxies and thus life itself (Noble).
The Big Bang model that attempts to explain the origin and structure of the universe incorporates the talents of many individuals through the course of more than 150 years of study. Many times facing opposition similar to that of Galileo and Copurnicus, these cosmologists used a deductive approach in solving the greatest question in the history of science. The findings and observations of these emminant scholars forced them to draw the conclusions they arrived at. Every prediction that quantum physics and the theories of relativity have made regarding the origin and the state of the universe have either been observed and confirmed and/or not proven to be false. That is in essence the reason we have arrived at this cosmology, fully confident that our science and technology can look back in time 15 billion years and see the birth of our universe.
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