I will describe the Reeh-Schlieder theorem and its Important Corollary. And I will introduce how to construct Local Algebras.
In this journal club, I will introduce the 2M++ galaxy redshift catalogue. I will introduce the process of constructing the catalogue and the cosmological parameters which could be deduced from the catalogue.
## References
-[arXiv:1803.04993](https://arxiv.org/abs/1803.04993)*Notes on Some Entanglement Properties of Quantum Field Theory* by *Edward Witten*.
-[arXiv:1105.6107](https://arxiv.org/abs/1105.6107)*The 2M++ galaxy redshift catalogue* by *Guilhem Lavaux* and *Michael J. Hudson*.
-[arXiv:1504.04627](https://arxiv.org/abs/1504.04627)*Cosmological parameters from the comparison of peculiar velocities with predictions from the 2M++ density field* by *Jonathan Carrick* at al.
| 1.13 | 2.30 PM | 6420 | Zhen-Min Zeng and Yu-Ping An |
## Title: *Axion inflation*
## Reporter: Zhen-Min Zeng
| 3.3 | 2.30 PM | 6420 | Yong Zhou |
## Title: *Cosmography and PAge approximation*
## Reporter: Yong Zhou
## Abstract
We will review the basic scenario of Axion inflation with \phi F \widetuilde{F} coupling term which include the induction of primordial GWs,primordial curvature perturbations and primordial Nongaussianity.With the production of the gauge quanta during inflation,there are many phenomenological differences comparing to the Standard model like parity violation backreaction effect etc. Finally, I will introduce a machanism to enhance the GWs on small scales which may be decteted in the future GWs observation.
In this talk, I will report my recent work on cosmography to expand a model-independent Hubble expansion rate on cosmic age and redshift, and compare it with Parameterization based on the cosmic Age (PAge) approximation.
## Title: *Is Hilbert Space of Gravity Theory Factorizable?*
## Reporter: Yu-Ping An
## Abstract
In this seminar, I will discuss factorizability of Hilbert space in quantum gravity. It is well-known that gravity theory shows lots of non-local properties. However, when considering QFT in curved space-time, we have always been assuming, without much thinking, that Hilbert space of the whole theory can be factorized into direct product of subspaces on different space-time points. First, I will show how arguments that lead to black hole information paradox are related to this assumption. Then I will present a counter-example of this commonly used assumption, which may be seen as an evidence for the so-called “holography of information”. This report is mainly based on Suvrat Raju’s three papers:
## References
-[Arxiv:2002.02448](https://arxiv.org/abs/2002.02448)*The Holographic Nature of Null Infinity* by *Alok Laddha* et al.
-[Arxiv:2012.05770](https://arxiv.org/abs/2012.05770)*Lessons from the Information Paradox* by *Suvrat Raju*.
-[Arxiv:2110.05470](https://arxiv.org/abs/2110.05470)*Failure of the split property in gravity and the information paradox* by *Suvrat Raju*.
