Big Bang Singularity
Ralph Alpher in the Genesis of Big Bang:
To physicists it is just as bad to say that one can divide a finite number by zero and get away with it as it is to ascribe to a physical system the existence of a singularity.
Things must have changed a lot in physics since then. Singularity has long become a legal physical quantity.
One Comment
Actually, the singularity problem is one of the major problems of Big Bang cosmology. Generally the biggest problems of BB model are
1. flatness, homogeneity and isotropy of the universe
2. the absence of magnetic monopoles
3. creation of structures (anisotropies in CMB)
4. the BB singularity
5. the smallness of the vacuum density (cosmological constant)
The first 3 can be solved by resorting to the theory of inflation. The last 2 are still unresolved.
The truth is that true singularities cannot exist in nature (i used the word true to differentiate between coordinate singularities which can exist and singularities that are of non-coordinate nature).
So it is not true that singularity has become legal. In fact the exact opposite is true. I must say that supporters of BB cosmology try to avoid the problem by saying that BB cosmology can only account for times greater than Planck’s time (t=10^-43 s).