**Is a Big Bang Impossible?**

**B.W. Wojciechowski**

**Cosmologists have examined the current expansion of the universe and, despite a mysterious speeding up of recent, it all makes sense. The expansion can be reversed in our models of expansion by retracing its origins mathematically. This gives us the age of the universe since the Big Bang: something like 13.6 billion years ago.**

**We are told that 13.6 billion years ago is the time when all the mass, energy and any mysterious dark matter etc. started to appear in the process of expansion of the Big Bang. Before that all this stuff was contained in a “singularity.” The calculation is based on the currently observed expansion of the universe. And it fits many calculations regarding the physics we observe.**

**But here is my question. As we calculate the “contraction” in order to get to the singularity we come to a time when the density of the compressed universe reaches the point when it all collapses into a Black Hole. After that we know nothing. How big would the Black Hole be? How long during a contraction we postulate as we seek the origins of the universe before things proceeded to the Black Hole stage in this “contraction” calculation? Is that the real age of the universe?**

**The other matter is the supposed singularity that gave birth to the universe. Its density would be much greater than any Black Hole we know. If the singularity did exist (within a Black Hole?), how did it explode? Black Holes are not known to explode. They may “evaporate” but they do not explode. So, if an exploding singularity inside a Black Hole is impossible in our understanding of physics how did the universe originate?**

**But, let us say that a singularity did explode inside a Black Hole, how long did it take before expansion of the volume of the contents of the Hole were diluted below the Black Hole limit? At that point the Black Hole will have dissolved giving rise to the expanding universe we observe. That is the only time we can say the observable universe was born.**

**However we cut it, there is the intervening Black Hole question in the expansion and contraction scenario. I have missed something important if this issue has been explained somewhere.**