A chemical catalyst can be described as:
Catalysis (/kəˈtælᵻsᵻs/) is the increase in the rate of a chemical reaction due to the participation of an additional substance called a catalyst (/ˈkætəlᵻst/). With a catalyst, reactions occur faster and require less activation energy. Because catalysts are not consumed in the catalyzed reaction, they can continue to catalyze the reaction of further quantities of reactant. Often only tiny amounts are required.
There are many physical processes, that do need a huge amount of energy to get started. Think of nuclear fusion, but also simple macroscopic things like rolling something up-hill, so that it can roll down the other side of the hill.
Now let's assume, physical catalysts are found. These hypothetic things/fields/particles reduce the amount of energy needed to initiate a reaction (think domino tiles, not chemical reactions like burning). In the course of this action they themselves will not be consumed.
(If you yell "conservation of energy!" right now, let's just assume, that the physics behind the mechanism is not completely understood yet, but the net energy of the system at times $t_0$ (start of reaction) and $t_1$ (end of reaction) is the same.)
Some things will not work, especially not reduction of entropy (converting thermal energy into mechanical energy by "un-frictioning").
What could be invented with physical catalysts? Some things off the top of my head, that might work:
- extremely dense batteries based on nuclear fusion (store by fusing H to He, obtain vice versa, but perfectly controlled by the amount of catalyst present)
- better drives, weapons, ... because chemical energy can be transfered into kinetic energy with almost zero loss (thanks to some convoluted processes in the presence of a catalyst)
- macroscopic "tunneling" through barriers (no need for "up-hill" energy investment followed by "down-hill" gain, because catalysts take care of that)
These would surely be only some primitive examples of the first generation of things using physical catalysts. Where could such a development lead to?