Cold fusion is a broad term for a type of controlled nuclear fusion that can be induced and sustained at room

temperature. It's called cold fusion, because normal room temperature, or somewhere thereabouts,

is quite cold compared to the environment in which fusion reactions typically take place.

The pressure and heat are often quite extreme, as both are generally required, to force

elements that typically would not combine to combine, which is the fusion part of cold fusion,

and that combination of elements is what creates energy. Early research in this space actually

began back in the 1920s, when a couple of Austrian scientists seemed to have witnessed

hydrogen converting into helium. So the element with an atomic number of one, changing into the element

with an atomic number of two, implying that the process they were experimenting with, which involved

dividing pieces of palladium into tiny bits, in turn causing those bits to absorb hydrogen,

actually caused that hydrogen to combine into helium.

Which, well, that would have been amazing, except that that's not what happened.

Those scientists later retracted their report, indicating that the helium they had detected

was actually naturally occurring helium

from the air that they had interpreted as being otherwise, as being the consequence of this

thing that they were doing. Several other fairly big-name researchers and institutions invested

their time in resources in this field soon after, attempting various approaches to see if they could combine elements

in this way to create a new element, but also, and this was the real goal for most of these

projects, to create energy as a byproduct of that combination process. Because that energy

creation, the same type that takes place in stars, including our sun, by the way.

If we could make that happen at something closer to room temperature rather than star temperature,

we might be able to create abundant, clean energy, with few or even zero harmful byproducts.

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