What is the difference between black hole singularity and big bang singularity?
The Big Bang singularity is a point of zero volume, but very high mass, which makes the density infinite. This singularity contained all of the matter and energy in the Universe. The initial moment of the cyclopean explosion very well remains a mystery ' however, astronomers and physicists believe that after the tiniest fraction of a second, the strong nuclear force and the electromagnetic force separated, which probably caused the Universe to begin inflating. The Big Bang itself created space, time, and all of the matter and energy we know today.
Black hole singularities are created after the core of a very massive star collapses beyond an imaginary sphere called the event horizon. Since these singularities are infinitesimally small, they possess infinite density.
The differences are that black hole singularities, of course, do not contain all of the matter and energy in the Universe because there are so many of them. There was only one Big Bang singularity, and it contained the whole Universe. Another difference is that space and time were born from the Big Bang singularity, and black holes actually stretches out space to the point where it probably rips the fabric of space-time, and ends time altogether.
According to Stephen W. Hawking, singularities either occur entirely in the future or entirely in the past. In this case, black hole singularities always lie in the future (if you were to go near one, your time will come to an end), and the Big Bang singularity always lie in the past (if you were able to rewind time, galaxies will become closer together, eventually coming together at a point).
Joel Novicio, Undergraduate Physics Student, South San Francisco
Depends on which type of black hole you consider. If you consider a simple non-rotating black hole, I can't really think of a difference between the singularities (other than the fact that one exists within the universe whereas the other 'was the universe' - but this is irrelevant).
In both cases the singularity was a single point where the curvature of space time are infinite. It is believed that at this point the general theory of relativity (almost universally accepted as 'the' accurate description of gravity) ceases to hold true.
The singularity of a rotating black hole is essentially the same except that it exists in a ring (thus the name ring singularity). The consequences of a rotating black hole (if they exist - we have no direct proof that any type of black holes exist) however, are very different from non-rotating ones.
K Shaban, CS/Physics Student, Carnegie Mellon
A black hole singularity is the dimensionless point where all matter pulled into the back hole is concentrated. It has infinite density and therefore does not exist within space-time as it is the point of infinite curvature of space-time.
The big bang singularity is where all the mass of the universe used to be concentrated. It had all of the properties of a black hole singularity but from it 'grew' space time and matter was released into this space as the fundamental particles of very high energy. This is the big bang. Therefore, the main difference is that a black hole singularity is the end of space time (and pulls matter in) and the big bang singularity is the beginning of space time (where matter and space were made 'real').
Martin Archer, Physics A Level Student, Surrey, UK
'One thing I have learned in a long life: that all our science, measured against reality, is primitive and childlike - and yet it is the most precious thing we have.'