My home is the air, the earth, and the sea

Question

My home is the air, the earth, and the sea,
Between highs and lows you are sure to find me.
I am boisterous and loud, as bright as the sun,
But those who can see me or hear me are none.
I am born with a goal, I live in a shell,
I accompany those who greet and farewell.
I have numerous forms, interactions that last,
Like the tooth of a saw or the shock of a blast.
As fast as the wind, I fly through the dark,
None can outrun me, not falcon nor shark.
My essence is motion, my voice is a trill.
Occasionally I will attempt to stand still.
I live everywhere, both far and near,
But when you try to find me, I disappear.

This riddle is from SBHacks 2021!

Answer 1

Are you a

WAVE?

My home is the air, the earth, and the sea,

Waves can travel through the air, the earth, or of course the sea.

Between highs and lows you are sure to find me.

Waves are made up of highs and lows.

I am boisterous and loud, as bright as the sun,

Sound waves are loud, light waves are bright.

But those who can see me or hear me are none.

You can't see the wave shape in light or hear it in sound.

I am born with a goal, I live in a shell,

No idea about the shell.

I accompany those who greet and farewell.

Waving hello or goodbye.

I have numerous forms, interactions that last,

Many types of waves ...

Like the tooth of a saw or the shock of a blast.

Such as the zigzag shape of a saw blade, or shock waves.

As fast as the wind, I fly through the dark,

Sound waves?

None can outrun me, not falcon nor shark.

Light waves are the fastest thing in the universe.

My essence is motion, my voice is a trill.

Waves are always moving.

Occasionally I will attempt to stand still.

Not sure about this or the "trill" from the last line.

I live everywhere, both far and near,

Waves are everywhere.

But when you try to find me, I disappear.

If you try to pin down a wave, it stops moving and it's not a wave any more?