 Lexi Mcneil

2022-07-22

Scientists say that it is impossible to reach a temperature of zero kelvin, because the atoms will stop moving, and the volume of the substance will become zero, But we have reached the pico kelvin temperature, which is almost zero, and there is no difference between it and zero, so why do they say it is impossible? and The laws of physics still work at picokelvin. kartonaun

The difference is that 0 is not the same as ${10}^{-9}$. The latter is nearly zero, but it's not zero.
Why does it matter? Consider for example Charles's Law, which says that for gases, $V/T$ is a constant if the pressure is kept constant. If $T={10}^{-9}K$, there's no problem applying the equation. But if T=0, the law breaks down since division by zero is undefined.
This doesn't mean that the laws of physics break down at $T=0$, after all Charles's Law is just a special case of the ideal gas law which does not break down at $T=0$. But it does show that 0 is special and not the same as ${10}^{-9}$, ${10}^{-12}$ or any small but nonzero number, and you might need to treat T=0 differently.

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