The Quantum Gravity Connection between Inflation and Quintessence
Round 1
Reviewer 1 Report
This paper is a well-written review, which discusses comprehensively the scaling solution in quantum gravity interpolating between a UV fixed point (corresponding to cosmological inflation) and an IR fixed point (corresponding to dark energy domination). I recommend it for publication.
I have only several (very) minor corrections:
- On line 220: “device” should be “devise”
- On line 631: “must” should be “most”
- In the caption of Figure 2: It would be useful to define the quantities N_{V,S,F}, since there they appear for the first time in the paper. Of course, they are defined below eq. (19), but that is much later than Figure 2.
Author Response
Thank you for the suggestions. I have extended the caption of fig.2 and corrected the typos.
Reviewer 2 Report
This article uses scale invariance based on quantum gravity to derive scaling solutions in the ultraviolet and infrared regimes for a scalar field coupled to gravity. In this way it implements a predictive model that can describe both the early inflationary epoch and the late-time dark energy dominated epoch of the evolution of the Universe. The article is very well written, interesting, and as far as I can see, it is scientifically sound. For this reason I have no hesitation to recommend its publication.
I have one minor comment: An important part of the argument, particularly concerning the avoidance of fine-tuning issues, is based on quantum scale symmetry. This is a topic that I, and probably quite a few readers, are not familiar with. While there is an extensive review by the author (that is referenced in the text), I would think it useful to provide a short reminder of what this is about. I could imagine that one or two sentences around line 75 would suffice (3rd paragraph of of point (3)).
Beyond this, I found only a single typo: in line 632 (just before the end of article): "rendering MUST particles massive" should probably be MOST.
Author Response
Thank you for the useful suggestion. I have added a short paragraph after line 71. I also have corrected the typo.
Reviewer 3 Report
The subject of this paper is interesting, and the author presents a particular approach to the problem of unifying inflation and Dark energy which is interesting. Unfortunately concerning the selection of cited papers, the author restricts his attention mostly to researcher that have worked with him or generally belong to his network ignoring for example : Eduardo Guendelman, Ramón Herrera, Pedro Labrana, Emil Nissimov, , Svetlana Pacheva, Published in: Gen.Rel.Grav. 47 (2015) 2, 10 • e-Print: 1408.5344 [gr-qc] and others, to help widen the circle of authors being cited beyond the circle of friends of Professor Wetterich, so at least those papers I mentioned should be cited.
Author Response
Thank you for mentioning this reference that I have now included.
