Cosmology - In the Real Beginning
These initial photons are now visible as very cold cosmic background radiation at an average 2.725 degrees above absolute zero (called degrees Kelvin or K.). The frequency of radiation is related to temperature. An electric light bulb has a temperature that produces visible light. Red hot iron produces visible light at a lower wave length using a lower temperature. Less hot iron could produce infrared radiation that is not visible at all but is felt as radiant heat. The lower temperature again produces a lower frequency. This is how the wave lengths of radiation is associated with temperature. The universe has steadily cooled from the intense initial heat of the Big Bang. The wall of light that produced the cosmic background radiation was at a far higher temperature (4880 degrees F. or 2967 K.) when the light last bounced off matter. However, that wall is now retreating from us at a high percentage of the speed of light. This produces a Hubble red shift that reduces the light frequency to a temperature associated with microwave radio wavelengths, 2.725 K. With the cosmic background radiation we are seeing the hot hydrogen plasma just before it cooled to become atomic hydrogen. This exact agreement with the temperature at which hydrogen becomes plasma is another important confirmation of the Big Bang.
Sound waves in air physically exist as small variations in air pressure. The early universe had similar waves that propagated through the intense hot plasma that then existed. Just as differences in air pressure can cause differences in temperature so can these waves in the early plasma of the universe. That difference is incredibly small. One small region of space might have cosmic background radiation at 2.7251 K and another might have 2.7249 K. Modern instruments in reading these early ripples in cosmic background radiation are quite literally listening to echoes of the Big Bang itself. This is the third category of confirmation of the Big Bang derived from the cosmic background radiation. The astonishing accuracy of current instruments gives very reliable evidence about these early conditions. It is like a photograph of what really happened.
The Hubble telescope has examined galaxies that existed in the first billion years after the Big Bang. The light from these distant galaxies has traveled over ten billion years to reach us. What we observe belongs to a much younger age of the universe. The early galaxies are on average much different than the older galaxies in our region of space. Our galaxy is shaped as a rotating disk with spiral arms. The early galaxies are amorphous, fuzzy spheres because they have not had the time for the angular momentum in the globular cluster to form the classic spiral disks we now see.
Most galaxies have a massive black hole at the center. The greater amount of matter in a galactic core makes it easier to accumulate enough matter so that even light cannot escape. That is why they call it a black hole. A black hole will not by itself be visible at a great distance. However, the intense gravitation of a black hole can accelerate surrounding particles to nearly the speed of light and those particle will produce intense radiation.
In early galaxies, the many black holes that are doing this are called quasars. They are so bright that the light from the surrounding stars is drowned out. Supermassive black holes have been observed in many nearby galaxies. None of them are quasars. The black hole at the center of our Milky Way (26,000 light years away) is called Sagitarrius A*. It almost certainly was a quasar when the universe was younger. These stark differences provide powerful visual evidence understandable to a layperson confirming the great age of the universe with specific changes over time since the Big Bang.
Theologians have often attempted to define God as that which created the universe and then presume that since there must be such a cause that there must be a God. Well, logic requires me to ask if everything must have a cause what caused God? Obviously if God can be without prior cause so could the Big Bang.
A greater problem of this desire for a first cause is the recent innovation in theory that paints a picture of no discrete boundary to the start of time. This innovation comes from Stephen Hawking and others. He asks us to consider that going back in time would be quite similar conceptually to going to the North Pole.
What happens when we reach the North Pole and continue going? Well, there is no problem we just continue. He calls this the 'no boundary condition.' If people ask what is north of the North Pole the answer is that the question is meaningless.
The no boundary condition totally removes the question of what could be before an initial time boundary at the Big Bang. It is likely to be a continuous space time surface quite different from our normal experience of time as a one directional flow.
God is often described as the mysterious, that which is not understood. The purpose of science is to explain what is not understood and thus where it succeeds it makes God unemployed. The enormous sophistication of our current understanding of space and time goes a long way toward doing this.
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