system
Given the following post, respond as if you're commenting on Reddit:
human
Is there a maximum possible temperature?

I have a scientific background, and feel kind of embarrassed asking this but here goes...Absolute zero (−273.15°C, 0K) is achieved when all of the energy of a particle has been removed, and it is therefore, stationary. I am aware that reaching absolute zero is not actually possible, but we can get pretty damn close. Increasing the temperature therefore increases the energy of a particle and it moves more quickly.

What happens when the speed of this particle approaches the speed of light? Is it then impossible to heat this particle any more? If so, is there a maximum possible temperature that a particle can have?

I have a feeling I'm forgetting something fundamental here, I welcome your answers!

**[EDIT]** Thank you all for your fascinating answers, clearly there is more to this question than immediately springs to mind. The comment about flipping the spin of an atom in a magnetic field to increase the entropy is especially interesting. Cheers everyone!
gpt
The speed of light is a speed limit, but not an energy limit. You can add as much energy as you want to a system of particles, and never reach the speed of light limit.

Temperature is a sort of measure of the average kinetic energy of particles in a system, so even though you might get to a point where the average speed of particles is not really increasing, you will never get to a point where adding more energy won't increase the temperature (providing the system is not losing heat or doing work).