Asimov's Foundation: the Jump through hyperspace (1942 onward)
The Jump as a solved problem: a region that is neither space nor time, crossed between two instants, with the work done beforehand at a calculating machine.
Kind: fiction · Loophole: L4 · Notability: N1 · Coherence: F3 · Causality: C-dodges · Last reviewed: 2026-09-12
The drive as depicted
The drive is defined on the first pages of Foundation (1951), in the opening section "The Psychohistorians", as the young mathematician Gaal Dornick travels to Trantor. Asimov states the light barrier and the loophole in one paragraph. Travel through ordinary space cannot go faster than light, which would mean years between even neighbouring inhabited systems, and so the Jump remains "the only practical method of travelling between the stars"; through hyperspace, "neither space nor time, matter nor energy, something nor nothing", one can cross the Galaxy "in the interval between two neighboring instants of time" [HIGH] S1 (Foundation, Part I, chapter 1; the passage as reproduced in the Historical Dictionary of Science Fiction and at technovelgy). What the passenger feels is a trifling jar, a small internal kick that ends before he is sure he felt it [HIGH] S1. The ships are "hyperatomic"; the engine and the mathematics are never described, and Gaal's whole experience of interstellar travel is waiting for the next Jump and noticing when it has happened.
That opening section was written for the 1951 book; the four stories that follow it appeared in Astounding from May 1942 and take the Jump for granted, with traders and warships moving about the Galaxy and the emphasis always on what happens at either end [HIGH] S3 (Wikipedia, Foundation, publication history). Across the original trilogy the recurring practical rule is that a Jump has to be computed before it is made, and that the computation takes time: ships wait in normal space while the course for the next Jump is worked out, and a long trip is a chain of Jumps with intervals between them [MED] S1 (Foundation and Empire, 1952, and Second Foundation, 1953, from memory of the voyages of Toran and Bayta and of Arkady Darell; not rechecked against the text this session). In Foundation's Edge (1982) the sequels modernise the machinery: Trevize's ship the Far Star has a gravitic drive and a computer that calculates a Jump in moments and can run a series of them, where older ships needed days between Jumps and a safe distance from any large mass before making one [MED] S1 (Foundation's Edge, from memory of the early chapters; Wikipedia confirms only the gravitic ship and the 1982 date). The Jump also carries the series' communication: the hyperwave relay, which lets messages cross the Galaxy at Jump speed.
Asimov wrote one story that prices the Jump, and it is not in the Foundation series. In "Escape!" (1945, collected in I, Robot, 1950) the calculating machine the Brain designs a hyperatomic ship, and the humans who ride it cease to exist for the duration of the jump and return, which the Brain has decided is a joke rather than a death [HIGH] S1 (from memory of the story; stable and well known).
Origin and lineage
Isaac Asimov wrote the first Foundation story for John W. Campbell's Astounding Science Fiction in 1942, and Campbell was the editor who had put the word hyperspace into space travel eleven years earlier (Campbell 1931) [HIGH] S2 (Historical Dictionary of Science Fiction, entry "hyperspace", citing Campbell 1931 and Asimov 1951). Asimov's usage, and the shape of the Jump (instantaneous, computed, felt as a jar), became the pulp default and then the general one; the Historical Dictionary's citation trail runs from Campbell through E. E. Smith (1939) and Sturgeon (1941) to Asimov (1951) and on to 2022 [HIGH] S2. No physics proposal is named in the series, and Asimov, who was a biochemist by training, never claimed one. The lineage page planned for this line is hyperspace-the-word (see lineage).
Lineage: Hyperspace: the word.
Which loophole, and why
L4, leave the manifold. Asimov's own words settle it: the ship passes through a region that is not space, and normal space is where the ship is between Jumps. There is no tunnel, no carried bubble and no faster object; the rule that nothing in ordinary space beats light is stated in the same paragraph as the loophole. A secondary L5 exists in the hyperwave relay, which is the same mechanism for messages, and is not scored separately here.
The physics cousin is Kaluza-Klein and the hyperspace reading, the register's MAN-1 worked through. Extra dimensions in physics are compact or warped, a point in them is a point of the same spacetime with another coordinate and ordinary matter cannot leave the brane; "neither space nor time" has no counterpart. The nearest physics to an instantaneous Jump is the brane-bulk shortcut, whose bill is a new warped dimension, energy densities of the early universe to make the gain noticeable and CAU-1's antitelephone unless the bulk supplies a frame. Asimov's Galaxy has the frame and none of the rest.
The rules it keeps
- Nothing in ordinary space exceeds light. Stated in the defining passage and never broken: the ships accelerate normally between Jumps [HIGH] S1.
- The Jump is instantaneous in Galactic time. "Between two neighboring instants" in 1951 and the same in 1982 [HIGH] S1.
- A Jump must be computed first, and the computation is the bottleneck: hours in the trilogy, moments with the Far Star's computer, which is presented as an advance and not a change of physics [MED] S1.
- Distance from masses before a Jump, stated in Foundation's Edge as the older constraint that gravitic ships relax [MED] S1.
- Long trips are chains of Jumps, each landing the ship in normal space [MED] S1.
The mark is F3. The work names a real limitation (the light barrier), states its loophole in one sentence and applies the loophole's own rules consistently for forty years of instalments. It does not build story around the cost of the physics, which is what F4 asks; the cost of a Jump in the Foundation series is a calculation, and calculation is what the series is about.
What it ignores
The register's first question is never asked. A Jump is instantaneous "for everyone": the Galaxy keeps one calendar (the Galactic Era) and the interval between two instants is the same interval on Trantor and on Terminus. That is a preferred frame in the sense of CAU-4, and the mark is C-dodges on the strength of the stated rule, not of any argument in the text: no instalment mentions that a Jump in one frame is a trip to the past in another, and no character ever receives a hyperwave message before it was sent. The rule answers the constraint without naming it. The register would also ask what a Jump spends, what hyperspace is made of and why masses disturb it; the series says nothing on any of them as of 2026-09-12. Asimov's one engagement with the Jump's cost to the traveller is in "Escape!" and is played as a joke.
Constraint scoring
Every entry in the register, one row each, verdict from the fiction vocabulary, with a note that says where in the work the engagement or rule occurs.
| Constraint | Verdict | Note |
|---|---|---|
| CAU-1 | SILENT | The antitelephone is never mentioned; hyperwave messages and Jumps are treated as simply fast, in every instalment from 1942 to 1993. |
| CAU-2 | SILENT | No time machine is built or forbidden; the series has no closed loops and never says why not. |
| CAU-3 | SILENT | Two Jump ships are the register's time machine with an assembly step; the Galaxy has millions and the question is not raised. |
| CAU-4 | RULE | The Jump takes no time at all in the Galaxy's one calendar ("between two neighboring instants", Foundation I.1), which fixes the FTL speed in one frame; the stated rule is the preferred-frame escape, though the series never says that is what it is for. |
| CAU-5 | N/A | No entanglement device; the hyperwave relay is a Jump for messages, not a quantum channel. |
| ENE-1 | SILENT | What a Jump spends is never said; "hyperatomic" is the only word offered for the engine. |
| ENE-2 | SILENT | A trip that beats light through flat space needs negative energy somewhere; the series prices the Jump in computation and nothing else. |
| ENE-3 | N/A | The quantum inequality bound is for a warp-bubble wall; a Jump has no wall. |
| ENE-4 | N/A | Pocket geometry is a warp-bubble modification; not this class. |
| ENE-5 | N/A | The Natário class needs a shift vector on flat slices; a ship that is nowhere for an instant is outside it. |
| ENE-6 | N/A | No negative energy is claimed. |
| ENE-7 | N/A | Topological censorship prices a wormhole handle in our spacetime; the Jump goes through no handle. |
| CON-1 | N/A | No bubble, no horizon; the pilot is the navigator, and the series makes the calculation the whole of piloting. |
| CON-2 | SILENT | The Jump needs no route laid in advance: Trevize Jumps into unexplored space in Foundation's Edge, and the series never asks whether a first flight is possible without infrastructure. |
| CON-3 | N/A | No tube; ships Jump both ways. |
| STA-1 | N/A | Bubble instability; no bubble. |
| STA-2 | N/A | No wormhole throat. |
| STA-3 | N/A | No chronology horizon is ever built. |
| HAZ-1 | N/A | The register's burst is the particle load of a decelerating bubble wall; a ship arriving from nowhere has swept up nothing. |
| HAZ-2 | N/A | No horizon, no Hawking flux; the passenger feels a jar and nothing more. |
| HAZ-3 | N/A | No throat, no tidal bound. |
| LOR-1 | ENGAGES | The defining passage states that travel through ordinary space cannot exceed light speed and draws the consequence (years between stars) before offering the Jump; the light barrier is on the page as the reason the drive exists. |
| LOR-2 | N/A | No tachyons. |
| LOR-3 | N/A | No signal in a medium. |
| LOR-4 | N/A | Neither the Scharnhorst effect nor OPERA bears on a Jump. |
| WRP-1 | N/A | Not a warp drive; the ship is not carried, it is elsewhere. |
| WRP-2 | N/A | No moving shell. |
| WRP-3 | N/A | No positive-energy warp claim. |
| MAN-1 | ENGAGES | "Neither space nor time, matter nor energy, something nor nothing" is the entry's "separate space with laxer rules" defined by negation; the series depicts exactly the thing the entry says physics does not supply, and says so in its first chapter. |
Sources
- S1 Asimov, I., Foundation (Gnome Press, 1951), Part I "The Psychohistorians", chapter 1, for the defining passage; the four later parts first in Astounding Science Fiction, May 1942 to October 1944. Passage read as reproduced at technovelgy.com and in the Historical Dictionary of Science Fiction; the book not reopened this session.
- S1 Asimov, I., Foundation and Empire (1952) and Second Foundation (1953), for the calculation intervals between Jumps. From memory; marked MED above.
- S1 Asimov, I., Foundation's Edge (Doubleday, 1982), for the Far Star's gravitic drive and computed Jumps. From memory; Wikipedia read for the date and the gravitic ship.
- S1 Asimov, I., "Escape!", Astounding Science Fiction (August 1945), collected in I, Robot (1950). From memory.
- S2 Sheidlower, J. (ed.), Historical Dictionary of Science Fiction, entry "hyperspace" (sfdictionary.com), read in full: citation trail from Meadowcroft (1928) and Campbell (1931) to Asimov (1951).
- S3 Wikipedia, "Foundation (Asimov novel)" and "Foundation's Edge", for publication history.
- S3 technovelgy.com, "Jump through hyperspace", and the Delta's D&D blog post "Asimov on hyperspace, pt. 1" (2013), both reproducing the Foundation passage with page numbers 4 to 5.