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Relativistic collisions
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Energy and momentum conservation at high speed.
Energy and momentum are conserved but not rest mass: kinetic energy can convert to new particles. The invariant mass √(E_tot² − p_tot²c²) sets the available energy.
In collider, two protons at 6.8 TeV each give 13.6 TeV.
Colliders beat fixed targets as more energy is available.
In more detail
Relativistic collisions conserve total energy and momentum, but the kinetic energy available for creating new particles depends on the centre-of-mass energy. High-energy collisions can produce new particles.
Real-world uses
- Particle colliders such as the LHC create new particles through relativistic collisions.
- The Higgs boson was discovered in such collisions.
- Particle physicists analyse high-energy collisions by applying conservation of energy and momentum with relativistic formulas.
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Frequently asked questions
What is centre-of-mass energy?
The total energy available in the frame where the total momentum is zero.
Why is it important?
It determines the maximum mass of particles that can be produced.
Do the same conservation laws apply in relativity?
Yes, energy and momentum are conserved, but the formulas for them are relativistic.
Related topics in Relativity
Relativistic Doppler effect · Aberration of light · Four-vectors · Particle accelerators and relativity · Mass–energy in nuclear reactions · Relativistic electromagnetism