In this paper, the tachyon scalar field model is compared with the $\Lambda CDM$ standard model using a set of observational data consisting of BBN, H(z), CMB, BAO, SNIa and $f\left(z\right){\sigma }_8$. The comparison is carried out at background and perturbation levels. Since the mass of the tachyon scalar field is very small and its effective sound speed is in the order of the speed of light $(c_{eff}\approx 1)$, the dark energy component remains homogeneous. The tachyon scalar field of dark energy model depends on its potential, therefore we consider the tachyon scalar field model based on a potential which is very popular in the literature, here in this work $V\left(\varphi \right)=\frac{n}{4\pi G}{(1-\frac{2}{3n})}^{1∕2}{(\varphi -{\varphi }_0)}^{-2}$ is chosen as the potential for the tachyon scalar field model. The evolution of equation of state parameter, density parameter, dimensionless Hubble parameter, deceleration parameter, the linear growth factor, the growth rate and $f\left(z\right){\sigma }_8\left(z\right)$ for the tachyon scalar field model is compared with the $\Lambda CDM$, the holographic and the new agegraphic DE models. Although the tachyon scalar field model guarantees the acceleration of the universe’s expansion, the evolution of the deceleration parameter of the tachyon scalar field model enters to accelerating phase earlier than the other models. The growth rate of the cosmic structures, $f\left(z\right)$, is non-negligible at low redshifts for the tachyon scalar field model. In order to put constraints on the free parameters of the tachyon scalar field model, a standard Markov Chain Monte Carlo (MCMC) minimization method is utilized based on recent expansion and growth observational data. According to the values of the Akaike and Bayesian information criteria, we show that the tachyon scalar field model is inconsistent with the observational data and we can omit the tachyon scalar field model with the considered potential in this paper. Despite the considered potential is very popular in the literature, we should search for a better potential according to the available observational data.

本文将Tachyon标量场模型与 $\Lambda Cd\mathrm{中号}$ 使用一组由BBN，H（z），CMB，BAO，SNIa和 $F（ž）{\sigma }_8$。比较是在背景和摄动水平上进行的。由于Tachyon标量场的质量非常小，并且其有效声速约为光速$（C_{ËFF}\approx \mathrm{1个}）$，暗能量分量保持均匀。暗能量模型的Tachyon标量场取决于其势能，因此我们考虑基于势能的Tachyon标量场模型，该势能在文献中非常流行，在本文中$V（\varphi ）=\frac{ñ}{4\pi G}{（\mathrm{1个}-\frac{2}{3ñ}）}^{\mathrm{1个}∕2}{（\varphi -{\varphi }_0）}^{-2}$被选为Tachyon标量场模型的潜力。状态方程，密度参数，无量纲哈勃参数，减速参数，线性增长因子，增长率和$F（ž）{\sigma }_8（ž）$ 将Tachyon标量场模型与 $\Lambda Cd\mathrm{中号}$，全息和新的年龄DE模型。尽管Tachyon标量场模型保证了宇宙膨胀的加速，但Tachyon标量场模型的减速参数的演化要比其他模型更早地进入加速阶段。宇宙结构的增长率，$F（ž）$对于Tachyon标量场模型，在低红移下不可忽略。为了限制tachyon标量场模型的自由参数，基于最近的扩展和增长观测数据，使用标准的马尔可夫链蒙特卡洛（MCMC）最小化方法。根据Akaike和贝叶斯信息准则的值，我们表明tachyon标量场模型与观测数据不一致，因此可以忽略具有潜在潜力的tachyon标量场模型。尽管考虑的潜力在文献中非常受欢迎，但我们应该根据现有的观测数据寻找更好的潜力。