>"The Newton's cradle is a device that demonstrates the conservation of momentum and the conservation of energy with swinging spheres. When one sphere at the end is lifted and released, it strikes the stationary spheres, transmitting a force through the stationary spheres that pushes the last sphere upward. The last sphere swings back and strikes the nearly stationary spheres, repeating the effect in the opposite direction. The device is named after 17th-century English scientist Sir Isaac Newton. It is also known as Newton's pendulum, Newton's balls, Newton's rocker or executive ball clicker (since the device makes a click each time the balls collide, which they do repeatedly in a steady rhythm).[1][2]

A five-ball Newton's cradle

A typical Newton's cradle consists of identical metal balls suspended in a metal frame so that they are just touching each other at rest.

Newton's cradle in slow motion

When one of the end balls ("the first") is pulled sideways, the attached string makes it follow an upward arc. When it is let go, it strikes the second ball and comes to nearly a dead stop. The ball on the opposite side acquires most of the velocity of the first ball and swings in an arc almost as high as the release height of the first ball. This shows that the last ball receives most of the energy and momentum of the first ball. The impact produces a compression wave that propagates through the intermediate balls."

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PDS: Now this is interesting!

Consider the three balls in the center of a Newton's Cradle with five balls...

They are relatively fixed in their position, that is, they have two degrees of freedom in a straight line, along a horizontal axis.

But this degree of freedom, this horizontal axis -- is blocked off by the balls on their sides...

So, when they are impacted by force (from another adjacent ball), they must transfer this force to their opposite adjacent neighboring ball.

Now, once you've wrapped your mind around that understanding, now it's time to talk about Particles -- as are understood in Classic Mechanics...

You see, particles, as understood by Classic Mechanics are things that can move, that in theory (the Classic Mechanics theory) have a virtually infinite amount of degrees of freedom (much like physical objects that are not mounted in place, that say, exist in space, do.)

Classical Mechanics thinks about Particles -- as having a (virtually) infinite amount of degrees of freedom.

But...

WHAT IF THEY DIDN'T?

?

In other words, what if a better view of particles was that of the three center balls in Newton's Cradle, that is, CONSTRAINED ALONG ONE OR MORE DEGREES OF FREEDOM?

?

In fact, let's go a step farther...

WHAT IF PARTICLES -- DIDN'T ACTUALLY MOVE AT ALL?

How would this be possible, you might ask?

Well, instead of thinking of space as being empty, let's think of it as being full...

That is, a plenum, not a vacuum.

This plenum then -- is not unlike one of the three center balls in Newton's Cradle.

When a particle (which is actually just a force seeking balance) impacts an area of this plenum -- then what happens?

It transfers this force, this "particle" -- to it's neighbor!

Which in turn transfers it to its neighbor!

And so on and so on, until there's enough absorbtion (remember that the balls in Newton's Cradle do absorb a little bit, a tiny bit of the force each time, because they are not perfectly balanced or aligned, this is why it eventually slows down, why the "wave dampens", or call the effect whatever you will) in space, such that the particle either fizzles out over enough distance, or stops moving, or what-have you... (a lot of effects are possible!))

Well, that's one view of Particles...

Yes, it's a CRACKPOT theory(!), and I'm not saying it's right, and it's not the only way of looking at / engineering particles... but it might be interesting to think of particles in this fashion (and see what could be engineered! <g>) from time to time!

It's one viewpoint, one way of viewing particles, in a whole bunch of other ones...