Slow-roll Natural & Hilltop inflation in Rastall gravity

IF 1.4 3区物理与天体物理 Q3 PHYSICS, FLUIDS & PLASMAS

High Energy Density Physics Pub Date : 2025-12-01 Epub Date: 2025-10-28 DOI:10.1016/j.hedp.2025.101238

Isaac M. Vitohekpon , Biswajit Deb , Ines G. Salako , V.A. Monwanou , Atri Deshamukhya

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引用次数: 0

Abstract

This study provides a concise analysis of inflation under Rastall gravity by examining three types of potential such as the power law, natural, and hilltop potentials. Choosing a minimal interaction between matter and gravity, we derived the modified slow-roll parameters, the scalar spectral index

(n_{s})

, the tensor spectral index

(n_{T})

, and the tensor-to-scalar ratio

(r)

. For a general power-law potential as well as for Natural & Hilltop inflation, we calculated these quantities and subsequently plotted their trajectories in the

(n_{s}, r)

plane. For the power-law potential, only the cases

n = 2 / 3

and

n = 1

satisfy the observational constraint of the Planck 2018 data. The natural potential analysis shows that the mass scale is crucial, with better compatibility achieved at

f = 5 M_{Pl}

compared to

f = 10 M_{Pl}

. Lastly, the Hilltop potential results indicate that among the cases studied (

m = 3 / 2, 2, 3,

and 4), only

m = 3 / 2

exhibits marginal consistency with observational bounds, while the other cases fail to produce acceptable

n_{s} - r

trajectories.

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拉斯托重力中的慢滚自然膨胀和山顶膨胀

本研究通过考察幂律、自然势和山顶势等三种势，对拉斯托引力下的暴胀进行了简明的分析。选择物质与重力之间的最小相互作用，我们推导了修正的慢滚参数，标量谱指数（ns），张量谱指数（nT）和张量-标量比(r)。对于一般幂律势和自然山顶膨胀，我们计算了这些量，并随后在（ns,r）平面上绘制了它们的轨迹。对于幂律势，只有n=2/3和n=1的情况满足普朗克2018数据的观测约束。自然电位分析表明，质量尺度是至关重要的，与f=10MPl相比，f=5MPl的相容性更好。最后，Hilltop势结果表明，在研究的情况（m=3/2,2,3和4）中，只有m=3/2与观测边界具有边际一致性，而其他情况无法产生可接受的ns - r轨迹。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

High Energy Density Physics PHYSICS, FLUIDS & PLASMAS-

CiteScore

4.20

自引率

6.20%

发文量

审稿时长

6-12 weeks

期刊介绍： High Energy Density Physics is an international journal covering original experimental and related theoretical work studying the physics of matter and radiation under extreme conditions. ''High energy density'' is understood to be an energy density exceeding about 1011 J/m3. The editors and the publisher are committed to provide this fast-growing community with a dedicated high quality channel to distribute their original findings. Papers suitable for publication in this journal cover topics in both the warm and hot dense matter regimes, such as laboratory studies relevant to non-LTE kinetics at extreme conditions, planetary interiors, astrophysical phenomena, inertial fusion and includes studies of, for example, material properties and both stable and unstable hydrodynamics. Developments in associated theoretical areas, for example the modelling of strongly coupled, partially degenerate and relativistic plasmas, are also covered.