Can Earth or any spherical object in space act as a particle collider?

This is most probably a dumb idea as I'm far from deep physics knowledge but I was thinking.
What if Earth is hot inside not because of the pressure and the radioactivity but because it's mass attracts particles (similarly to gravitational lensing) and they collide right in the Earth's center?

Why would they not collide with various parts of the Earth before getting anywhere near the center? You are positing some magical particles that can avoid all of the particles that make up the Earth, arrive at the center at the same time, and then collide with each other. Really?

What is "gravitational lensing" in ths context? Some nontrivial part of the earths internal energy is residual heat from collisions due to its viotent accretion history, because of gravity. Wikipedia is good.