In LQC, the bounce can avoid the singularity by applying plancke scale quantum gravitational effects to effectively cause a "bounce" - this simultaneously avoids the classical singularity while transitioning into classical GR once certain scales are reached. Essentially singularity of BB can be resolved, by a modification on the EFE which only has an effect in extreme conditions.(adsbygoogle = window.adsbygoogle || []).push({});

For LQC to cause a bounce, the common model would require a previous classical spacetime with a contraction phase leading to

"the density and curvature enter the Planck scale quantum geometry effects become dominant

creating an effective repulsive force which rises very quickly, overwhelms the classical gravi-

tational attraction, and causes a bounce thereby resolving the big bang singularity." Extract from http://arxiv.org/PS_cache/arxiv/pdf/1005/1005.5491v1.pdf

My question is this: If LQC requires a classical spacetime - but a contracting one, in order for an initial "bounce", then does this indicate that rather than the idea of multiple identical "bounces", that the current "bounce" of the Universe is a distinct phase, ruled by certain physical laws (These laws being GR but initially with modified quantum geometry effects at Planck scale to allow for resolution of singularities)? Does this imply that the previous phase of the Universe, the phase prior to the current "bounce" predicted by LQC, was ruled by different physical laws?

What does LQC say in regards to continuity - if a contracting classical space-time caused the current bounce, what caused that classical spacetime to contract. For some reason intuition is screaming at the back of my head saying that the matter dominance of the Universe has a role to play?

As most knowledgeable people who post on here know and as my name implies I am a novice, so any misonceptions I am happy for people to point out.

Thanks

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# LQC beginners question

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