As for what you own, above and below your little plot, the scholar/poet William Empson - a degree in Mathematics followed by a degree in Literature, published his path-breaking Seven Types of Ambiguity aged 24 - makes it all as clear as mud.
LEGAL FICTION
Law makes long spokes of the short stakes of men.
Your well fenced out real estate of mind
No high flat of the nomad citizen
Looks over, or train leaves behind.
Your rights extend under and above your claim
Without bound; you own land in Heaven and Hell;
Your part of earth's surface and mass the same,
Of all cosmos' volume, and all stars as well.
Your rights reach down where all owners meet, in Hell's
Pointed exclusive conclave, at earth's centre
(Your spun farm's root still on that axis dwells);
And up, through galaxies, a growing sector.
You are nomad yet; the lighthouse beam you own
Flashes, like Lucifer, through the firmament.
Earth's axis varies; your dark central cone
Wavers, a candle's shadow, at the end.
William Empson, 1906-1984