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**Through the big bang : Continuing Einstein's equations beyond a cosmological singularity.** / Koslowski, T.A.; Mercati, F.; Sloan, D.

Research output: Contribution to Journal/Magazine › Journal article › peer-review

Koslowski, TA, Mercati, F & Sloan, D 2018, 'Through the big bang: Continuing Einstein's equations beyond a cosmological singularity', *Physics Letters B*, vol. 778, pp. 339-343. https://doi.org/10.1016/j.physletb.2018.01.055

Koslowski, T. A., Mercati, F., & Sloan, D. (2018). Through the big bang: Continuing Einstein's equations beyond a cosmological singularity. *Physics Letters B*, *778*, 339-343. https://doi.org/10.1016/j.physletb.2018.01.055

Koslowski TA, Mercati F, Sloan D. Through the big bang: Continuing Einstein's equations beyond a cosmological singularity. Physics Letters B. 2018 Mar 10;778:339-343. https://doi.org/10.1016/j.physletb.2018.01.055

@article{be8b889244bd4defa034e9f63bc36467,

title = "Through the big bang: Continuing Einstein's equations beyond a cosmological singularity",

abstract = "All measurements are comparisons. The only physically accessible degrees of freedom (DOFs) are dimensionless ratios. The objective description of the universe as a whole thus predicts only how these ratios change collectively as one of them is changed. Here we develop a description for classical Bianchi IX cosmology implementing these relational principles. The objective evolution decouples from the volume and its expansion degree of freedom. We use the relational description to investigate both vacuum dominated and quiescent Bianchi IX cosmologies. In the vacuum dominated case the relational dynamical system predicts an infinite amount of change of the relational DOFs, in accordance with the well known chaotic behaviour of Bianchi IX. In the quiescent case the relational dynamical system evolves uniquely though the point where the decoupled scale DOFs predict the big bang/crunch. This is a non-trivial prediction of the relational description; the big bang/crunch is not the end of physics – it is instead a regular point of the relational evolution. Describing our solutions as spacetimes that satisfy Einstein's equations, we find that the relational dynamical system predicts two singular solutions of GR that are connected at the hypersurface of the singularity such that relational DOFs are continuous and the orientation of the spatial frame is inverted.",

author = "T.A. Koslowski and F. Mercati and D. Sloan",

year = "2018",

month = mar,

day = "10",

doi = "10.1016/j.physletb.2018.01.055",

language = "English",

volume = "778",

pages = "339--343",

journal = "Physics Letters B",

issn = "0370-2693",

publisher = "ELSEVIER SCIENCE BV",

}

TY - JOUR

T1 - Through the big bang

T2 - Continuing Einstein's equations beyond a cosmological singularity

AU - Koslowski, T.A.

AU - Mercati, F.

AU - Sloan, D.

PY - 2018/3/10

Y1 - 2018/3/10

N2 - All measurements are comparisons. The only physically accessible degrees of freedom (DOFs) are dimensionless ratios. The objective description of the universe as a whole thus predicts only how these ratios change collectively as one of them is changed. Here we develop a description for classical Bianchi IX cosmology implementing these relational principles. The objective evolution decouples from the volume and its expansion degree of freedom. We use the relational description to investigate both vacuum dominated and quiescent Bianchi IX cosmologies. In the vacuum dominated case the relational dynamical system predicts an infinite amount of change of the relational DOFs, in accordance with the well known chaotic behaviour of Bianchi IX. In the quiescent case the relational dynamical system evolves uniquely though the point where the decoupled scale DOFs predict the big bang/crunch. This is a non-trivial prediction of the relational description; the big bang/crunch is not the end of physics – it is instead a regular point of the relational evolution. Describing our solutions as spacetimes that satisfy Einstein's equations, we find that the relational dynamical system predicts two singular solutions of GR that are connected at the hypersurface of the singularity such that relational DOFs are continuous and the orientation of the spatial frame is inverted.

AB - All measurements are comparisons. The only physically accessible degrees of freedom (DOFs) are dimensionless ratios. The objective description of the universe as a whole thus predicts only how these ratios change collectively as one of them is changed. Here we develop a description for classical Bianchi IX cosmology implementing these relational principles. The objective evolution decouples from the volume and its expansion degree of freedom. We use the relational description to investigate both vacuum dominated and quiescent Bianchi IX cosmologies. In the vacuum dominated case the relational dynamical system predicts an infinite amount of change of the relational DOFs, in accordance with the well known chaotic behaviour of Bianchi IX. In the quiescent case the relational dynamical system evolves uniquely though the point where the decoupled scale DOFs predict the big bang/crunch. This is a non-trivial prediction of the relational description; the big bang/crunch is not the end of physics – it is instead a regular point of the relational evolution. Describing our solutions as spacetimes that satisfy Einstein's equations, we find that the relational dynamical system predicts two singular solutions of GR that are connected at the hypersurface of the singularity such that relational DOFs are continuous and the orientation of the spatial frame is inverted.

U2 - 10.1016/j.physletb.2018.01.055

DO - 10.1016/j.physletb.2018.01.055

M3 - Journal article

VL - 778

SP - 339

EP - 343

JO - Physics Letters B

JF - Physics Letters B

SN - 0370-2693

ER -