What exactly are resonances?

[captain]

what exactly are resonances? are they particles, energy,..?

 

[Astronuc]

what exactly are resonances? are they particles, energy,..?

In what context?

A reasonable description would be particles or particle systems in an excited (unstable) energy state.

http://en.wikipedia.org/wiki/Resonance#Resonances_in_quantum_mechanics

One can think of baryonic resonances - Lambda, Sigma, Delta, Xi, Omega particles - http://hyperphysics.phy-astr.gsu.edu/hbase/particles/baryon.html
http://en.wikipedia.org/wiki/List_of_baryons

Or nuclear resonances with respect to neutron absorption cross-seciton.

 

[sir-pinski]

Resonances refer to a phenomenon in physics where a system or object vibrates at a specific frequency or range of frequencies. This can occur when an external force is applied to the system, causing it to oscillate at its natural frequency. Resonances can also occur within the system itself, such as with the vibrations of atoms or molecules.

In terms of particles, resonances can refer to subatomic particles that have a short lifetime and decay into other particles. These particles are typically produced in high-energy collisions, such as in particle accelerators, and their existence is predicted by theories such as quantum mechanics and the standard model of particle physics.

Resonances can also be seen as a form of energy, as the vibrations created by the system can be transferred to other objects or systems, causing them to vibrate at the same frequency. This is why resonance is often used in musical instruments, where the vibrations of one string can cause another string to vibrate and produce sound.

Overall, resonances can refer to both particles and energy, depending on the context in which it is used. It is a complex phenomenon that has been studied and observed in various fields of physics, and its understanding has contributed to advancements in technology and our understanding of the natural world.