Final answer:
Pionless effective field theory simplifies calculations of nuclear interactions by focusing on very low energy ranges where pion exchange is less significant.
The exclusion of pions makes the model more tractable but limits its range of valid applications. Pions are mesons with masses approximately 135-139.6 MeV/c².
Step-by-step explanation:
Pionless effective field theory is chosen because it simplifies the mathematical framework of nuclear interactions by excluding pions, which typically mediate the strong force at longer ranges.
This allows for focus on nucleon-nucleon interactions at very low energies where pion exchange becomes less relevant. Excluding pions simplifies calculations substantially and makes computations more tractable.
The exclusion of pions impacts the theoretical framework by restricting the applicable energy range of the theory. In a pionless EFT, phenomena at energy scales where pion effects are significant cannot be accurately described.
However, within its range of validity, it provides a powerful tool to analyze low-energy phenomena with fewer degrees of freedom to consider.
The mass of a charged pion is approximately 139.6 MeV/c², while the neutral pion has a mass of about 135.0 MeV/c².
A meson is a class of particles that includes pions and other particles with a mass between that of an electron and a nucleon.