• Question: Does every black hole contain a singularity?

    Asked by Mason The Amazing :) to Andrew, Hina, Ian, Kathryn, Leah-Nani, Xu on 14 Jun 2018.
    • Photo: Kathryn Burrows

      Kathryn Burrows answered on 14 Jun 2018:

      In a way yes….and no. I like to define a black hole as an object with mass so great even light cannot escape, a real thing. A singularity is a mathematical infinite which cannot be removed by a change of observers or co-ordinates. In the mathematical model of black holes they all contain a singularity but there is a caution here. Usually whenever a physical theory contains a singularity it is shown sooner or later that the singularity does not really exist and it is due to some missing effect that we are not yet aware of. The singularity is not real as such so nothing can ‘contain’ it, it is an indication of the breakdown of our mathematical models. So you could say currently every black hole is associated with the breakdown of our mathematical models.

    • Photo: Leah-Nani Alconcel

      Leah-Nani Alconcel answered on 15 Jun 2018:

      A black hole is an object, while a singularity is a mathematical idea. The maths that describes black holes uses singularities. So a black hole can’t be said to contain a singularity since a singularity is not an object.

    • Photo: Andrew Margetts-Kelly

      Andrew Margetts-Kelly answered on 20 Jun 2018:

      A singularity is a mathematical anomaly when you analyse what happens inside a black hole when the numbers approach infinity.
      The problem with that assessment is that it would imply wormholes really do exist and also more problematically that a white hole conjugate exists for every black hole. The mathematical white hole is the opposite end of the singularity in a black hole where the matter gets spewed out. We haven’t observed any of these white holes yet but do know about plenty of black holes; so we have to conclude at the moment that singularities do not exist in black holes.