标题： 暗能量状态方程中的特征以及哈勃图中的调制 显示英文标题

标题： Features in Dark Energy Equation of State and Modulations in the Hubble Diagram

摘要： 我们根据三年期WMAP（WMAP3）数据以及与其他可能的宇宙学观测结果（如星系聚集（SDSS）和Ia型超新星（SNIa））的结合，探讨暗能量状态方程（EOS）的时间依赖性。 我们主要关注状态方程振荡或存在局部峰的情况。 通过使用马尔可夫链蒙特卡罗（MCMC）方法进行全局分析，我们发现当前的观测结果，特别是WMAP3 + SDSS数据组合，允许状态方程出现较大的振荡，这些振荡可能在（残差）哈勃图上留下振荡特征，这种振荡可能被未来的观测如SNAP检测到，甚至可能被目前正在进行的SNIa观测检测到。 暗能量状态方程的局部峰也可能在CMB、LSS和SNIa上留下痕迹。 在峰出现在低红移且有效状态方程接近-1的情况下，CMB和LSS观测无法对这些可能性施加约束。 然而，几何观测如（未来）SNIa有可能检测到这些特征。 另一方面，当局部峰出现在SNIa不可探测的高红移区域时，未来的精确观测如伽马射线暴、CMB和LSS可能会检测到这些特征。 特别是，我们发现高红移区域的类似峰的暗能量状态方程可能负责WMAP在l\sim 30-50范围内的特征，这很有趣，值得进一步研究。 显示英文摘要

摘要： We probe the time dependence of the dark energy equation of state (EOS) in light of three-year WMAP (WMAP3) and the combination with other tentative cosmological observations from galaxy clustering (SDSS) and Type Ia Supernova (SNIa). We mainly focus on cases where the EOS is oscillating or with local bumps. By performing a global analysis with the Markov Chain Monte Carlo (MCMC) method, we find the current observations, in particular the WMAP3 + SDSS data combination, allow large oscillations of the EOS which can leave oscillating features on the (residual) Hubble diagram, and such oscillations are potentially detectable by future observations like SNAP, or even by the CURRENTLY ONGOING SNIa observations. Local bumps of dark energy EOS can also leave imprints on CMB, LSS and SNIa. In cases where the bumps take place at low redshifts and the effective EOS are close to -1, CMB and LSS observations cannot give constraints on such possibilities. However, geometrical observations like (future) SNIa can possibly detect such features. On the other hand when the local bumps take place at higher redshifts beyond the detectability of SNIa, future precise observations like Gamma-ray bursts, CMB and LSS may possibly detect such features. In particular, we find that bump-like dark energy EOS on high redshifts might be responsible for the features of WMAP on ranges l \sim 30-50, which is interesting and deserves addressing further.