Since the start of the year, I’ve received quite a few questions regarding absolute temperatures – highest and lowest, so I decided to start a brief discussion around the two values, in which I will give the basic facts about them, so feel free to step in and add more info or questions.

### Absolute zero

In thermodynamics, absolute zero is impossible to reach; it is the temperature at which entropy reaches minimum value, entropy being a property used to determine the energy not available for work, or to put it in layman terms, a state of  ‘molecular disorder’ of any substance. Absolute zero or absolute 0 K (0 degrees on the Kelvin scale, which is typically used for absolute values) equals −273.15° on the Celsius scale and −459.67° on the Fahrenheit scale.

Scientists have managed to get extremely close to absolute zero, at 100 picoKelvins, or 10-10 Kelvins, but as I said, reaching absolute zero is impossible, at least with our current knowledge. Researchers have noted some remarkable properties of matter, when they get close to this temperature, such as superconductivity.

Now, quite a lot of people know about this; but what many people don’t know is that similar to how there is a minimum possible accepted temperature, there is also a maximum temperature, called the Planck temperature.

### The Planck and maximum temperature

In the Planck temperature scale, 0 is absolute zero, 1 is the Planck temperature, and every other temperature is a decimal of it. This maximum temperature is believed to be 1.416833(85) x 1032 Kelvin degrees, and at temperatures above it, the laws of physics just cease to exist.

However, many don’t agree with this rather cosmological model and believe that as we continue to find out more and more things about the Universe we live in, the maximum temperature will continue to grow.

From what I have been able to find, the highest temperature obtained on Earth was 3.6 billion degrees, which even though is over 2.000 times hotter than the interior of the Sun, is only an insignificant fraction of 1032 degrees.