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  • Print publication year: 2012
  • Online publication date: August 2012

17 - The Big Bang, quantum gravity and black-hole information loss

Summary

I argue that the common idea of applying standard quantization procedures to the space-time geometry at the Big Bang to obtain a Planck-scale chaotic geometry is likely to be wrong, whilst such a quantum-geometric structure could indeed have relevance at black-hole singularities, these appearing to lead to a necessity of information loss. These issues are addressed by re-examining the basic rules of quantum theory in a gravitational context and by viewing things from the perspective of conformal cyclic cosmology, which is dependent upon the idea of conformal space-time geometry. This kind of geometry is also central to twistor theory, a subject in which significant advances have been made in recent years.

General remarks

What follows is essentially an extended summary of my actual talk, which I hope adequately conveys the gist of what I did report at the Stellenbosch meeting. I hope, also, that it can serve as a small token of the great respect that I have for George Ellis – in the honouring of his 70th birthday – both as a person and for the enormous contributions that he has made to science and to the cause of humanity.

I briefly discuss three different topics, all of which have relevance to the nature of quantum space-time geometry. The first has to do with the very framework of quantum theory in relation to Einstein's foundational principle of equivalence, and provides a reason for anticipating a change in the rules of quantum mechanics when superpositions of significant displacements of mass are involved.

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