哈勃时间计算器 — 公式
## The Hubble Time
The Hubble time is the reciprocal of the Hubble constant, giving the time scale of the present expansion.
### Formula
**t_H = 1 / H0**
To convert, note that 1 km/s/Mpc = 1 / (3.086 x 10¹⁹ s).
The Hubble radius c / H0 defines the distance at which the recession velocity equals the speed of light.
The Hubble time is the reciprocal of the Hubble constant, giving the time scale of the present expansion.
### Formula
**t_H = 1 / H0**
To convert, note that 1 km/s/Mpc = 1 / (3.086 x 10¹⁹ s).
The Hubble radius c / H0 defines the distance at which the recession velocity equals the speed of light.
计算示例
H0 = 70 km/s/Mpc.
- t_H = 3.086e19 / H0
- t_H = 3.086e19 / 70 = 4.409e17 s
- In Gyr: 4.409e17 / 3.156e16 = 13.97 Gyr
- Hubble radius = c / H0 = 299800 / 70 ≈ 4283 Mpc