arXiv:2412.15288v1 Announce Type: new
Abstract: We examine Friedmann-Lema^itre-Robertson-Walker cosmology, incorporating quantum gravitational corrections through the functional renormalization group flow of the effective action for gravity. We solve the Einstein equation with quantum improved coupling perturbatively including the case with non-vanishing classical cosmological constant (CC) which was overlooked in the literatures. We discuss what is the suitable identification of the momentum cutoff $k$ with time scale, and find that the choice of the Hubble parameter is suitable for vanishing CC but not so for non-vanishing CC. We suggest suitable identification in this case. The energy-scale dependent running coupling breaks the time translation symmetry and then introduces a new physical scale.
Future Roadmap
The conclusions of the research on Friedmann-Lema^itre-Robertson-Walker cosmology, incorporating quantum gravitational corrections, open up new avenues for exploration. Here, we outline a future roadmap for readers interested in this field, highlighting potential challenges and opportunities on the horizon.
1. Further Investigation of Quantum Gravitational Corrections
The findings of this study emphasize the importance of incorporating quantum gravitational corrections in cosmological models. Future research should delve deeper into the functional renormalization group flow of the effective action for gravity, exploring its implications for the overall dynamics of the universe. This will provide a more comprehensive understanding of the interplay between quantum effects and classical cosmological phenomena.
2. Non-Vanishing Classical Cosmological Constant
The research highlights the significance of considering the case with a non-vanishing classical cosmological constant (CC). It points out that the choice of the Hubble parameter as the identification of the momentum cutoff $k$ is not suitable in this scenario. Readers should focus on identifying an alternative suitable identification for the momentum cutoff in the presence of a non-vanishing CC. This will be crucial for accurately characterizing the energy-scale dependent running coupling and its impact on the dynamics of the universe.
3. Time Translation Symmetry and New Physical Scale
The energy-scale dependent running coupling introduced by quantum gravitational corrections breaks the time translation symmetry, leading to the emergence of a new physical scale. Future research should investigate the properties and implications of this new scale, such as its role in the evolution of the universe and its potential connections to observational data. Understanding the nature of this symmetry breaking and its consequences will contribute to a more comprehensive picture of the fundamental physics underlying cosmological dynamics.
4. Integrating Observational Data
To validate and refine the theoretical framework presented in this study, integrating observational data is essential. Researchers should aim to compare the predictions of the quantum improved coupling model with experimental data, such as cosmological observations, to test its validity and accuracy. This will require collaboration between theoretical physicists and observational astronomers, offering exciting opportunities for interdisciplinary research.
5. Incorporating Other Quantum Gravity Approaches
This research focuses on the functional renormalization group flow of the effective action for gravity. However, there are other approaches to quantum gravity, such as loop quantum gravity and string theory. Exploring the connections and potential synergies between these different frameworks will enrich our understanding of quantum cosmology and may lead to novel insights and breakthroughs. Encouraging collaboration and cross-pollination between these different approaches will be crucial for advancing the field.
Conclusion
The research on Friedmann-Lema^itre-Robertson-Walker cosmology incorporating quantum gravitational corrections presents intriguing new possibilities for understanding the dynamics of the universe. By further investigating quantum effects, addressing the challenges posed by non-vanishing classical cosmological constants, exploring the consequences of time translation symmetry breaking, integrating observational data, and incorporating other quantum gravity approaches, readers can contribute to the ongoing progress and advancements in this exciting field.