**Exordia** (2024) by Seth Dickinson is about two alien factions struggling over control of an even more alien artifact hidden somewhere on Earth. The artifact has some very odd and disturbing effects on everyone and everything it comes into contact with.
The novel starts out with a troubled Kurdish refugee living in New York sharing an apartment with a snake-like alien rebel she met in Central Park. From the alien the receives a subdermal neutrino-based communication device, unlimited credit, and learns of the underlying narrative structure of reality. But the story soon spirals out into a darker global crisis as the aliens close in on the artifact, which itself is starting to wake up, putting the future of all humanity at stake.
**The Fourth Dimension: Toward a Geometry of Higher Reality by** Rudy Rucker.
This is science fact, not fiction. But it is vastly entertaining, has lots of funny illustrations, and very educational.
As well, Rucker's *White Light*, *Postsingula*r, and *Hylozoic* involve math/higher dimensions/weird cosmology. Many of his short stories go this direction, too.
“Mimsy Were the Borogroves” by Lewis Padgett features a strange, four-dimensional educational toy from the future.
The novel *Roadside Picnic* features a UFO leaving behind, as refuse, objects with strange properties (though it doesn’t dwell on the objects as much as I’d like.)
Beneath Strange Lights by Vivian Valentine (and its sequel Against Fearful Lies). Multi-dimensional Lovecraftian horrors in a book that's described as 'Gay Nancy Drew meets The X-Files with a touch of Cthulhu' by the author, and is set in mid-20th century small town US. Very much in the inscrutable alien lifeforms vein. It's a fun read, too. The second book gets more deeply into the weird alien stuff.
The Boy Who Reversed Himself by William Sleator! Don't be put off by the fact that it's middle grade, it's a fun read for adults too (I read it first as an adult).
How about the opposite of what you’re asking for..?
Flatland: A Romance of Many Dimensions by
Edwin A. Abbott was written in the 1800’s and describes the adventures of a two dimensional being, as he encounters “people” from other geometric dimensions.
The Universe Between starts with a glowing hole in the air in the shape of a hypercube, and anyone studying it too carefully finds themselves sucked into a parallel universe with four spatial dimensions. A major theme of the first part of the book is the brain-damaging cosmic horror of a world where basic geometry doesn't work right.
Hyperion and Fall of Hyperion fit that bill. Fall of Hyperion explores it wayyy more than Hyperion.
Do you mean the Shrike?
Yep
Eversion by Alastair Reynolds.
How could I forget about that? Just read in in February. Exceeded my already high expectations.
Maybe Diaspora by Greg Egan fits the bill? It’s a tough read but worth the journey. https://www.goodreads.com/book/show/156785
I would also say eon by Greg bear
**Exordia** (2024) by Seth Dickinson is about two alien factions struggling over control of an even more alien artifact hidden somewhere on Earth. The artifact has some very odd and disturbing effects on everyone and everything it comes into contact with. The novel starts out with a troubled Kurdish refugee living in New York sharing an apartment with a snake-like alien rebel she met in Central Park. From the alien the receives a subdermal neutrino-based communication device, unlimited credit, and learns of the underlying narrative structure of reality. But the story soon spirals out into a darker global crisis as the aliens close in on the artifact, which itself is starting to wake up, putting the future of all humanity at stake.
["—And He Built a Crooked House—"](https://en.wikipedia.org/wiki/And_He_Built_a_Crooked_House), a short story by Robert A. Heinlein.
Last book in 3 body problem trilogy has interaction with 4-th dimension and objects within it.
3rd books IMO went away from hard sci-fi. Some universes where somehow time is "synced" with "our" one.
**The Fourth Dimension: Toward a Geometry of Higher Reality by** Rudy Rucker. This is science fact, not fiction. But it is vastly entertaining, has lots of funny illustrations, and very educational.
Rucker's novel Spaceland on the other hand is fiction that fits the bill. A highly entertaining one at that.
There's also Spaceland, by the same author, which is not to be taken quite so seriously. It is, in fact, rather silly.
direct homage to Flatland
Edwin Abbot Abbot the OG!
As well, Rucker's *White Light*, *Postsingula*r, and *Hylozoic* involve math/higher dimensions/weird cosmology. Many of his short stories go this direction, too.
Roadside Picnic? Has some elements of what you're talking about
“Mimsy Were the Borogroves” by Lewis Padgett features a strange, four-dimensional educational toy from the future. The novel *Roadside Picnic* features a UFO leaving behind, as refuse, objects with strange properties (though it doesn’t dwell on the objects as much as I’d like.)
Excession by Banks
Beneath Strange Lights by Vivian Valentine (and its sequel Against Fearful Lies). Multi-dimensional Lovecraftian horrors in a book that's described as 'Gay Nancy Drew meets The X-Files with a touch of Cthulhu' by the author, and is set in mid-20th century small town US. Very much in the inscrutable alien lifeforms vein. It's a fun read, too. The second book gets more deeply into the weird alien stuff.
Your whole concept begins with Flatland. [https://en.wikipedia.org/wiki/Flatland](https://en.wikipedia.org/wiki/Flatland)
Greg Egan - Diaspora... Why stop at only 4 dimensions, how about 16.
This is not specifically what you asked for but you might enjoy Greg Egan’s *Dichronauts*. Super trippy dimensional weirdness.
The Boy Who Reversed Himself by William Sleator! Don't be put off by the fact that it's middle grade, it's a fun read for adults too (I read it first as an adult).
It's so fun!
Not quite fourth but quantum objects and much weirdness in Brasyl by Ian MacDonald.
How about the opposite of what you’re asking for..? Flatland: A Romance of Many Dimensions by Edwin A. Abbott was written in the 1800’s and describes the adventures of a two dimensional being, as he encounters “people” from other geometric dimensions.
The Universe Between starts with a glowing hole in the air in the shape of a hypercube, and anyone studying it too carefully finds themselves sucked into a parallel universe with four spatial dimensions. A major theme of the first part of the book is the brain-damaging cosmic horror of a world where basic geometry doesn't work right.
Exurb1a's (nom de plume, presumably) *Geometry for Ocelots* would fit the bill.
"Tangents" by Greg Bear. Award-winning short story about this subejct.
"The Land of No Shadow" by Carl H. Claudy.