Phase Space Analysis of Barrow Agegraphic Dark Energy
Round 1
Reviewer 1 Report
Comments for author File: 
Comments.pdf
Author Response
The paper ”Phase space analysis of Barrow agegraphic dark energy” by Huang et al. discusses a dark energy model in the context of Barrow agegraphic dark energy with conformal time as IR cut off. The phase space analysis is performed and found an attractor which represent the DE dominated phase. The approach is interesting and deserves consideration. However, The points below should be fxed, before any recommendation for publication.
- Typos of the manuscript should carefully be checked. For example:
- There is ? after ref. 35, it should be fixed.
- Same thing on page 8, first line of Part C and so on...
Reply: We have checked the manuscript carefully and corrected these typos and grammatical mistake.
- There would exist many related works in recent past for the agegraphic dark energy models in theliterature. The significant progresses of this work should be stated more explicitly and in more detail beforethe BADE model introduced in ref.36 (see e.g. Phys.Lett.B 660 (2008) 113-117, Phys. Lett. B 657 (2007),228-231., Phys. Lett. B 673, 111-118 (2009), Mod.Phys.Lett.A 34 (2019) 11, 1950086, arxiv: 2205.01095
[gr-qc], arXiv:2205.03272 [physics.gen-ph], Phys.Dark Univ. 35 (2022) 100962.
Reply: We have stated these work detail in the second paragraph of Introduction.
- The differentiations from other versions of the agegraphic dark energy models with phase space analysisshould also be addressed.
Reply: The differentiations have been added in the forth paragraph of Introduction.
- A more detailed motivation for the BHDE needs to be explained in introduction with ref. 34 and 35(see e.g. Phys.Lett.B 825 (2022) 136844, Phys.Rev.D 103 (2021) 12, 123503, Int.J.Geom.Meth.Mod.Phys. 18(2021) 01, 2150014, Eur.Phys.J.Plus 137 (2022) 7, 783, Universe 7 (2021) 8, 268 and some others.
Reply: Thanks for your guidance. We have added the motivation of BHDE in the third paragraph of Introduction.
- 5. The conclusion section is very short. The authors should summarize their findings in more detail asthree different mode of BADE(Q) has been considered.
Reply: We have revised the conclusion and summarized the results detailedly in the conclusion.
Author Response File: Author Response.pdf
Reviewer 2 Report
Authors study 3 particular forms of Barrow Agegraphic Dark Energy via dynamical system analysis, aiming to
probe the cosmic history in the context of these 3 forms. Their results seems to have no obvious mistakes, from the mathematical point of view. However, the manuscript has a number of drawbacks.
First of all, the authors must present and discuss either the problems of the concordance model that are solved in the context of these two models or the conceptual principle (physics, mathematical or philosophical reasoning) that these models are based at.
Secondly, I believe that authors must discuss thoroughly the relation between the models presented here and the models of
https://arxiv.org/pdf/2012.14291.pdf, as there are significant similarities. For example, a discussion on whether to choose conformal time over the age of the universe should be present (this link could be helpful https://www.sciencedirect.com/science/article/pii/S0370269308000026?via%3Dihub).
Also, they state that
"
In the third case with β = 0 and the first case, the universe can evolve into the epoch dominated by dark energy at last, which is the same as the ΛCDM model described.
"
The existence of a Lambda CDM limit, either being exact or asymptotic as far as I understand has not presented whithin the manuscript. I think that the authors must explicitly provide this result.
Supposing that all the aforementioned results are addressed, one should assess constraints on model parameters that arise in order to maintain the standard cosmic history. Moreover, why authors consider alpha and beta to take values from 0 to 1 for both Q != 0 models?
There are numerous typos, missing references etc. For example, at the second paragraph, there are missing references, while at eq. 14 instead of \delta, the correct symbol is \Delta. Right after table 1, perhaps instead of "automatic", authors mean "autonomous". Moreover, right after section C, there are missing references.
Author Response
Authors study 3 particular forms of Barrow Agegraphic Dark Energy via dynamical system analysis, aiming to probe the cosmic history in the context of these 3 forms. Their results seems to have no obvious mistakes, from the mathematical point of view. However, the manuscript has a number of drawbacks.
First of all, the authors must present and discuss either the problems of the concordance model that are solved in the context of these two models or the conceptual principle (physics, mathematical or philosophical reasoning) that these models are based at.
Reply: The causality problem is avoided in the agegraphic dark energy with the age of the universe as IR cutoff, and the coincidence problem is solved naturally in the case with the conformal time as IR cutoff. These contents have been added in the second paragraph of Introduction. The models in this paper are based on the Barrow entropy which is explained detailedly in the third paragraph of Introduction.
Secondly, I believe that authors must discuss thoroughly the relation between the models presented here and the models of https://arxiv.org/pdf/2012.14291.pdf, as there are significant similarities. For example, a discussion on whether to choose conformal time over the age of the universe should be present (this link could be helpful https://www.sciencedirect.com/science/article/pii/S0370269308000026?via%3Dihub)
Reply: The paper(Barrow agegraphic dark energy https://arxiv.org/pdf/2012.14291.pdf) is Ref.[37] in the old version and Ref.[45] in the revised version. In Ref.[45], the authors analyzed the evolution of the cosmological parameters and the stability of these models, and the model without interaction term between dark matter and dark energy can be stable in the past. We have added this content in the last of the third paragraph of Introduction.In this paper, we discuss the evolution history of the universe by the phase space analysis method and find that this model can describe the evolution history of the universe.
Also, they state that " In the third case with β = 0 and the first case, the universe can evolve into the epoch dominated by dark energy at last, which is the same as the ΛCDM model described." The existence of a Lambda CDM limit, either being exact or asymptotic as far as I understand has not presented whithin the manuscript. I think that the authors must explicitly provide this result.
Reply: We have presented this result exactly in the abstract and conclusion.
Supposing that all the aforementioned results are addressed, one should assess constraints on model parameters that arise in order to maintain the standard cosmic history. Moreover, why authors consider alpha and beta to take values from 0 to 1 for both Q != 0 models?
Reply: In order to check whether BADE can maintain the standard cosmic history, we add Section IV and plot the evolutionary curves of Hubble parameter in Fig.5-7. For the situation Q>0, energy transfer from BADE to pressureless matter. We have added it under Eq.(8). This is the reason why we consider both alpha and beta take values from 0 to 1.
There are numerous typos, missing references etc. For example, at the second paragraph, there are missing references, while at eq. 14 instead of \delta, the correct symbol is \Delta. Right after table 1, perhaps instead of "automatic", authors mean "autonomous". Moreover, right after section C, there are missing references.
Reply: We have corrected these typos and grammatical mistake, and we also have checked the manuscript carefully.
Author Response File: Author Response.pdf
