发表机构
University of Urbino Carlo Bo（乌尔比诺卡罗博大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本文提出高维时空模型，其中额外维度紧致化为超球面，其高斯曲率和膨胀速率可模拟暗能量效应，拟合超新星数据支持存在3-4个正在收缩的额外维度。
AI 中文摘要
我们提出了一个高维时空的简单模型，其中四维子流形是FLRW度规，而额外维度被紧致化为超球面。我们计算了该模型的弗里德曼方程，发现额外维度与四维子流形的演化以非平凡的方式相互作用。我们证明，观测到的暗能量可以仅被解释为额外维度的高斯曲率和膨胀速率所产生的效应。我们计算了该模型中的光度距离，并推导了加速度参数q。我们发现Ωm和q在某种意义上被来自额外维度的项所“修饰”，因此一个仅包含物质（包括发光物质和暗物质）且具有额外维度的宇宙可以解释观测数据。我们发现额外维度不影响CMB谱，但这并不能解决哈勃张力问题。我们将模型拟合到SNe数据，并发现了当前正在收缩的3-4个额外维度存在的证据。
英文摘要
We present a simple model of a higher dimensional spacetime in which the 4d submanifold is a FLRW metric, while the extra dimensions are compactified to a hypersphere. We calculate the Friedmann equations of this model finding that the extra dimensions interact in a non-trivial way with the 4d submanifold evolution. We prove that what is observed as Dark Energy could be explained only as an effect due to the Gaussian curvature and the expansion rate of the extra dimensions. We calculate the luminosity distance in this model and derive the acceleration parameter q. We find that Ωm and q are in some sense dressed by terms coming from the extra dimensions, thus a Universe filled only with matter (both luminous and dark) and with extra dimensions can explain the observational data. We find that the extra dimensions do not affect the CMB spectrum, but this is not a solution to the Hubble tension. We fit our model to SNe data and find evidence for the presence of 3-4 extra dimensions which are presently contracting.
