Isaac Asimov admitted that he could not resist writing stories that involved time travel, even if there is no reason to believe that time travel is even possible. In my mind, this is no different than imaging that it is possible to fly your interstellar spaceship across the galaxy, even while admitting that it violates physical law to exceed the speed of light. Fun and entertainment are going to come out on top, a science fiction principle that needs to be remembered whenever a story starts taking itself too seriously.
Fan-fiction. As a fan of Isaac Asimov, I have been unable to resist writing Asimov fan-fiction stories, particularly ones that are inspired by his time travel novel, "The End of Eternity". For example, Foundations of Eternity was written as an imaginary account of the origins of both positronic robots and the type of time travel technology that Asimov invented for "The End of Eternity".
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time travel stories by Asimov
A longer list is here.
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Having recently written a new time travel story titled "
The Trinity Intervention" which features Asimov as a character, I wanted to systematically explore all of Asimov's time travel stories.
Temporal Sequence. The list of stories that is shown to the left really begins at the bottom with Asimov's "Cosmic Corkscrew", a "lost story" which is found in Chapter 1 of "The Trinity Intervention". In this blog post (below) I'll march through this list and comment on Asimov's time travel stories.
For this blog post, I'm including images that were generated by
ImageFX and
WOMBO Dream (for example, see
Figure 1) using text prompts such as, "
Cosmic Corkscrew, The Red Queen's Race, Pebble in the Sky, Day of the Hunters, Button, Button, The Immortal Bard, The End of Eternity, The Message, Gimmicks Three, Blank!, A Loint of Paw, Lastborn, Obituary, A Statue for Father, Thiotimoline to the Stars, Birth of a Notion, Fair Exchange? Foundations Edge The Instability Robot Visions Child of Time". The image that is shown to the right on this page (
Figure 2) was generated by ImageFX using that text prompt. ImageFX recognized that it had been given the titles of Asimov's time travel stories and the AI put them on imaginary book covers and rolled them out through Time like the frames of a film.
A Quantum Gap. What was going on in the world that motivated a young Isaac Asimov to write a time travel story in 1938? It was not just Asimov. Dozens of time travel stories were published in the 1930s. A science fiction novel called "For Us, the Living" was written by Robert A. Heinlein in 1938, but that story did not get published until 2003.
It seems clear that both Heinlein and Asimov were in the mood for time travel in 1938 because the whole new science fiction genre was enthralled by time travel stories. The letters columns of the science fiction magazines held enthusiastic reactions from fans to the published time travel stories. From our perspective in the internet age, we could say that time travel had gone viral during the 1930s. But what could a science fiction story teller say about the actual mechanism of time travel?
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Figure 3. Quantum dinosaurs.
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Not much. However, I think it is informative to consider a point in Time, ten years before 1938, in the year 1928, when a story called "
Armageddon 2419 A.D." was published in the
same issue of
Amazing Stories that brought readers
The Skylark of Space. Many time travel stories said nothing about the mechanism of time travel... it could have been magic for all most authors cared. But for stories such as "Armageddon 2419 A.D.", all it took was a lightening bolt or some other convenient nudge and off the hero went for a time travel adventure... no time travel technology required.
Quantal Time. Along with "Rip Van Winkle", "The Shape of Things to Come", "Armageddon 2419 A.D." and "The Black Flame" there are plenty of pre-1938 stories can take the blame for getting Heinlein and Asimov into the mood for time travel stories featuring dudes who make inexplicable quantum leaps through time.
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Figure 4. The Day of the Huntress.
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...
how he hit on his theory of spiraled time. We know that Asimov was a fan of H. G. Wells and "
The Time Machine" has its own "quantum leap" into the far future, into the Age of the
Eloi. Asimov stated that his ideas for the stories that he wrote came from the many books and stories that he had previously read (and he asked:
where else could they have come from?). To what extent was Asimov influenced by time travel stories such as "
The Atom-Smasher", "
The Time Valve", "
20,000 A.D.", "
Anachronism", "
A Flight into Time", "
The Reign of the Robots", "
Twilight", "
Trapped in Eternity" that he had previously read? Of particular interest is "
The Sands of Time" by P. Schuyler Miller (read
here), which was published in the
April 1937 issue of
Astounding Stories. "The Sands of Time" featured a complete 4D description of the universe: "
It’s spiraled ... in time!" In Miller's story, each coil is 60,000,000 years around, just the perfect duration for going back to see dinosaurs (see
Figure 3).
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Red Queen
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"
The Red Queen's Race" was published in the
January 1949 issue of
Astounding Science Fiction. "The Red Queen's Race" is mentioned, by name, in
Chapter 1 of "The Trinity Intervention".
Eddy Watson says: "
That was the time travel story where he introduced the idea of temporal
inertia. He imagined getting the energy that is needed for time travel
from nuclear fission."
Fusion power. In "The Red Queen's Race", a physicist figures out how to tap into the energy from a nuclear power plant in order to send a chemistry textbook back to the ancient Greeks, completing a time loop which caused a flowering of ancient Greek thought featuring atomistic thinking. Eddy is intrigued by the fact that a nuclear fission power source was used in Asimov's 1939 time travel story, but later, in "The End of Eternity", Asimov depicted the Eternity time travel system as being powered by thermonuclear energy (from the sun).
"
Pebble in the Sky" was published as a novel by Doubleday in
1950. Five years ago, in a blog post called "
Radiation Hypothesis", I wrote a fairly long account of major plot elements in "Pebble in the Sky" and I described it as "
a silly contrived mess of a novel". The time travel element in "Pebble in the Sky" is small and may have been a spin-off of whatever Asimov was thinking about when he wrote "Cosmic Corkscrew". A high energy accident propels Schwartz into the future where he is subjected to experiments with a mind-altering
synapsifier, activating his telepathic abilities.
Nuclear bombs were on Asimov's mind and so he introduced into "Pebble in the Sky" the idea that in the future, the surface of Earth was radioactive. Later, in his
robot novels, Asimov explained the radiation as being due to a "
nuclear intensifier" (see
Figure 5) that was used as part of a plot to force people to leave Earth and spread to distant exoplanets in the galaxy.
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Figure 5. Nuclear Intensifier
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"
Day of the Hunters" was published in the
November 1950 issue of
Future Combined with Science Fiction Stories. The story starts like a joke: three drunks in bar are discussing atomic bombs and since this is 1950 they soon get curious and want to use time travel to go on an adventure in the far past where they can discover what happened to the dinosaurs.
Four drunk science fiction fans walk into a bar... It is their lucky day because at the next table is another drunk, a professor, who knows what happened to the dinosaurs. The professor explains that he has already used
his time machine to go back in time and observed that there was a species of intelligent dinosaurs who had guns. They were hunters who killed just for fun (see
Figure 4). And now the human species is going to repeat that ancient history, causing a mass extinction and then humans will exterminate themselves.
"
Button, Button" was published in the
January 1953 issue of
Startling Stories. I previously commented on "Button, Button" in
this blog post from 2022. Asimov takes a loooong time getting around to the time travel plot thread that is in "Button, Button". First we have to hear about an attempt to build a
Hi Tek™ device that will allow people to play a flute just by thinking about it. I'm a big fan of technology-assisted telepathy stories, so this might seem like a promising start for a story by Asimov, but quickly the military steps in and uses the new brain-link technology as a way to "burn out" people's brains.😝
Asimov also depicted the inventor of the menta-flute as being hounded by the "musicians union". This is somewhat relevant today when there is resistance to the growing use of artificial intelligence among
some people in some professions.
Follow the Money. All of that overly-long menta-flute story-line that Asimov wrote into "Button, Button" is just prelude to the invention of time travel technology. However, there is a serious limit on the brand of time travel in "Button, Button": it takes HUGE amounts of energy to move even the smallest amount of mass through time.
So, in practical terms, only about one gram of matter can be shifted into the present from the past without breaking the energy bank. Thus "The Immortal Bard" (see below) had to wait until 1954. In "Button, Button", Asimov introduced "temporal viewing" technology, which can be used to view old documents of the past, and then transmit them into the future. The goal is to use the time machine feature of the Viewer and raise $$$ by bringing the signature of Button Gwinnett out of the past to sell to a collector. Signatures of Button Gwinnett are the rarest of the rare, and obtaining one could finally fund production of the menta-flute!
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Figure 6. Play the lion.
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I like science fiction stories that impose constraints on futuristic technologies, but Asimov really out-did himself on the contrived plot of "Button, Button". The whole scheme falls apart because the 200-year-old signature that gets recovered from the past is on paper that is not 200 years old.
Related Reading: Viewing the future. Using a brain to View the future.
"
The Immortal Bard" was published in the
May 1954 issue of
Universe Science Fiction. "The Immortal Bard" is a short "joke story" describing what happened after a physicist brought Shakespeare from the past into the future. Arriving in to 20th century, Shakespeare was intrigued by the idea that college students took courses devoted to his writings, so the physicist enrolled Shakespeare in one such college course, with bad consequences. Poor Shakespeare (
Figure 6) ended up with a failing grade in the course.
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A Time Machine.
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It is easy to build a time machine. I find "The Immortal Bard" particularly problematical for the same reason that I dislike "The Time Machine" by H. G. Wells. I never understood why Wells expected his readers to believe that a time machine could be built in the 1890s and it defies reader's expectations for Asimov to say that a lone physicist of the 20th century casually built a time machine.
You Fail. Worse still, the time machine was used it to bring multiple historical figures into the present, where they all had bad experiences and had to be sent back into the past. But none of that matters because Asimov is just out for a laugh, depicting the physicist as teasing the English professor for having failed his student, Shakespeare.
See my additional comments about "The Immortal Bard" in this blog post from 2022.
"
The End of Eternity" was published by Doubleday in
1955. I've previously blogged extensively about
"The End of Eternity" and I've described the novel as Asimov's masterpiece. In my recently competed fan-fiction story "
The Trinity Intervention" I depict a time loop by which Eddy Watson helped bring into existence "The End of Eternity". The character 'Eddy' is based on me, so the plot of "The Trinity Intervention" transfers my own love for "The End of Eternity" to Eddy, depicting that novel as having played a major role in stimulating Eddy's interest in science fiction story writing.
One of the intriguing elements of "The End of Eternity" is how Andrew Harlan is depicted as a dedicated citizen of the Eternity time travel organization, but then when he meets the luscious Noÿs Lambent, Andrew completely falls apart, even reaching the point where he is ready to destroy the Eternity time travel system itself in "fair exchange" for Noÿs.
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Woman of the Future. Image by
ImageFX, text added manually.
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There are hints in the story suggesting that Noÿs, who is from more than 10,000,000 years in our future, might have some
Hi Tek™ means to control the behavior of Andrew, beside simply wiggling her cute breasts. In "The Trinity Intervention", Manny the bumpha makes use of memory editing '
infites', information nanites, to alter the behavior of Eddy. I've also imagined that maybe Noÿs had some kind of telepathic ability. Sadly, Asimov never reveals to readers just exactly how Noÿs so successfully manipulates Andrew.
One of the best things about "The End of Eternity" is that Asimov depicted the technology for time travel as having been developed in the far future (and not in Joe's garage down the street) and the Eternity time travel system is depicted as being quite complex, requiring a large staff (including repairmen) to keep it operating. I much prefer this imagining of time travel technology, which one of the characters in the story says elevates time machines to the same relative complexity as spaceships.
The sexy Noÿs, a crafty woman from the far future, has every possible advantage over the poor bumbling Eternal, Andrew. Before ever actually meeting Andrew, Noÿs has previously used advanced
Reality Viewing technology to carefully observe the future that she will have with Andrew in a coming
Reality. Fortunately, this fantastic technology of Reality Viewing is not revealed until the last few pages of the story, allowing there to be some suspense in the minds of readers as the story unfolds. Towards the end of the story, after Andrew finally realizes that Noÿs is from the future and she has been manipulating his behavior, readers can wonder if Andrew will kill Noÿs and remain loyal to Eternity.
Related Reading. Before there was Noÿs, there was a beautiful time traveler from the future named Leela Zenken. See: "After 1,000,000 Years".
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The time travels of George Kilroy.
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"
The Message" was published in the
February 1956 issue of
The Magazine of Fantasy and Science Fiction. "The Message" is a short joke story, "explaining" the origin of "
Kilroy was here". In the story, an historical researcher, George Kilroy, from the 30th century was the origin of "Kilroy was here", hastily scribbling the phrase on a wall during a World War II battle in an attempt to make sure that someone would know he had been there briefly as an observer.
Time Loop. "The Message" is too short to get into any side issues, but it raises the question: how much did George Kilroy influence Earth's historical timeline by writing "Kilroy was here"? I'm rather surprised that Asimov did not write the story so as to depict time travelers from the future having to send someone named 'Kilroy' into the past in order to complete a time loop.
Related Reading: a clear deterministic time loop.
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Demon Deal.
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"
The Brazen Locked Room" was published in the
November 1956 issue of
The Magazine of Fantasy and Science Fiction, the same issue with Part 2 of Robert A. Heinlein's story "
The Door into Summer". "The Brazen Locked Room" is not much of a time travel story and it is not a science fiction story. A man makes a deal with a demon, which apparently involves receiving the magical ability to travel through time. He travels back in time and gets himself out of the deal.
Plot Holes. I'm completely "fantasy blind" so I don't know what the point of "The Brazen Locked Room" is. Readers are told that the man was given special powers by the demon, but until he wishes himself into the past, the man has no idea that he can travel through time. After this time travel event, there would now have to be two copies of the man in the past, but Asimov ignores that "small" inconvenient fact.
Related Reading: time travel made possible only by
diabolical power.
"Blank!" was published in the June 1957 issue of Infinity Science Fiction. I blogged about "Blank!" in 2022. I often complain about the absurdity of assorted dudes building time machines in their garage. For "Blank!", Asimov depicted two dudes who build a time machine, but this is even worse; soon they find their time machine stuck in some quiet corner of the universe where they cannot cause any time paradoxes, a literal and anthropomorphized depiction of the idea that the universe does not allow temporal paradoxes to arise.
As shown in the image that is to the right on this page, I could not resist making an imaginary magazine cover for the story "Blank!". "Blank!" was one of three related stories, one by Harlan Ellison.
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Stein's time niche.
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"
A Loint of Paw" was published in the
August 1957 issue of
The Magazine of Fantasy and Science Fiction. Back in 2022 I blogged about another Asimov story called "
Legal Rites". "Legal Rites" (published in
1950) is a fantasy story that includes a court case involving a ghost that ends up setting the legal precedent for ghosts to haunt houses. Readers of "A Loint of Paw" are told that a court case involving a thief, Monti Stein, "
introduced law to the fourth dimension".
Do the Math. The court session depicted in "A Loint of Paw" takes place in the year 3011, so readers are not asked to believe that time travel technology will be developed any time soon (from the reader's perspective). In fact, "A Loint of Paw" takes for granted that time travel exists and readers learn nothing about the available time machine technology in this far off century except for the fact that in the year 3000, Asimov expects it to cost far less than $100,000.00 to travel 7 years into the future.
However, if inflation continues at historical pace for the next 1,000 years then $100,000.00 would be worth very little in the year 3000. The legal issue under dispute in "A Loint of Paw" is that the criminal, Stein, used a time machine to move himself into the future, past the statute of limitations for his crime. However, the police still try to persecute Stein for his crime, arguing that time travel should not be used as a way to instantly move a criminal beyond the reach of the law. Mercifully, "A Loint of Paw" is only one page long. It ends with the judge's concise ruling: "A niche in time saves Stein".
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| Lastborn |
Neanderthal Time. The first time that I read "
Lastborn" was when I bought my copy of "
Nine Tomorrows" with cover art by Paul Lehr. That was also the last time. I did not like the story and I've never read it since I was in my
personal Golden Age of discovering science fiction. Supposedly, "Lastborn" was one of Asimov's favorite literary creations. There are some books by Asimov that I have read many times (probably "The End of Eternity" is the Asimov novel that I have read the most), but I won't be reading "Lastborn" again.
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Imaginary movie poster.
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In "Lastborn", rather than use Viewing technology (see Figure 8) to observe a Neanderthal in the past, a Neanderthal is brought into the present by means of time travel technology. Eventually, the Neanderthal is sent back to the past. The woman who was caring for the Neanderthal decides to also go into the past. I think Asimov has the correct ending the first time.
Note: "Lastborn" was later expanded to a full novel and was published as Child of Time. I've never read the novel.
"Obituary" was published in the August 1959 issue of The Magazine of Fantasy and Science Fiction. The story is told from the perspective of a woman, the wife of a physicist. For the type of time travel in "Obituary", it is possible to send objects into the future, but a person dies if sent to the future and returned to the past.
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How time travel works.
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More absurd constraints on time travel. Further, if sent to the future, an object only lasts until "the flow of time catches up" and the original object arrives at the once-future point in time. All of these restriction on time travel are absurd and contrived simply for Asimov's story. The man who discovers time travel wants to be able to see his own obituary. The story is really some sort of non-mystery mystery story in which the physicist's wife kills him... and gets away with it.
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"A Statue for Father" - image generated by ImageFX. The full sized image is here.
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Interstellar travel.
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"
A Statue for Father" was published in the
February 1959 issue of
Satellite Science Fiction. This is another contrived "joke" story that cripples time travel technology for comedic affect. I commented on "A Statue for Father" back in
2019. Some dinosaur eggs are retrieved from the past leading to an imaginary restaurant called "Dinachicken".
"Thiotimoline to the Stars", published in the "Astounding: John W. Campbell Memorial Anthology" in 1973 was the 4th in a series of stories that included "The Endochronic Properties of Resublimated Thiotimoline", "The Micropsychiatric Applications of Thiotimoline" and "Thiotimoline and the Space Age". I previously blogged about these stories in a 2022 blog post called "Memory Phantom".
"Thiotimoline to the Stars" is written from the perspective of the far future when the origins of thiotimoline have been lost in the hazy past. However, in this dazzling future of interstellar travel, it is some magical futuristic chemicals, like thiotimoline on steroids, that make space travel practical. These far future molecules are chronicpolymers that correctly interact with the time dimension so as to make sure that a spaceship built from the temporally-active polymers can arrive at distant locations with no net passage of time. But successful interstellar flights depend on rare spaceship pilots who have the "right stuff". Only some particularly talented individuals have the necessary intuitive ability to avoid a chronicpolymer spaceship from becoming a time machine.
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Figure 9. An amazing story.
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"
Birth of a Notion" was published in the
June 1976 issue of
Amazing Science Fiction. I've
previously blogged about "Birth of a Notion" and I even tried to discuss the story with the Gemini LLM. In "Birth of a Notion", the physicist who invents time travel is a science fiction fan. He goes back in time to 1925 and meets
Hugo Gernsback. Hugo is struggling to come up with a name for a new science fiction magazine, not to mention the name "science fiction" for the type of story that will be in the magazine. The time traveler suggests "Amazing" as the title, and the rest is history.
"Fair Exchange?" was published in the Fall 1978 issue of Asimov's SF Adventure Magazine. In "Fair Exchange?", time travel is used to recover from the past all of the music from the first collaboration between dramatist W. S. Gilbert and composer Arthur Sullivan.
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Figure 10. Temporal mind transfer.
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Temporal Transference. In "Fair Exchange?", there is not conventional time travel, just a way to transfer minds between people who are in different times. A man's mind is sent back to 1871, expecting to only be able to observe from inside another person of that time. However, time is changed and the music to
Thepsis is never lost in the new timeline. The only other major change is that the time traveler's wife is now dead, having been killed in a recent accident.
In my own stories, I have explored the idea of transfer of femtozoans through time as a form of "mind transfer" from the future to the past. Sadly, for "Fair Exchange?", Asimov did not explain how the "Temporal Transference" was accomplished.
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Figure 11. Visit the future! Image by ImageFX.
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"
Foundation's Edge" is not a time travel story. I don't mind pretending that the entire
Foundation Reality can be explained by positronic robots using time travel, but it makes no sense to list
Foundation's Edge as being a time travel story.
"Instability" is one of the stories that was collected in Gold. "Instability" is mercifully short. Every time that time travel takes place, it causes instability in the fabric of space-time and triggers a big bang explosion.
Before that "little fact" about big bang explosions is revealed to readers of "Instability", two men travel millions of years into the future to a point in time when another star is close to the current position of the sun. I was hoping that when they reached their destination, there would be welcome signs and advanced artificial life-forms of the far future would be expecting their arrival (see
Figure 11). No such luck.
I have not read "Robot Visions".
See Also: time travel by the alternate Asimov.
Related Reading: what is better than Time? Super-Time!
Notes on illustrations. The text elements in
Figure 1 were added manually by me. For
Figure 3, the main image was made by
Wombo Dream.
ImageFX made some dinosaurs, one of which I used as a reference for
Mr. Wombo, making it appear less scary (for the dinosaur in heaven). The dinosaur woman in
Figure 4 was generated by
Leonardo. For
Figure 6, the human figure was generated by
ImageFX. In
Figure 7, there is a small female figure that was generated by ImageFX when I asked for an image depicting a personification of Eternity. For both
Figure 8 and
Figure 9 I combined elements from two images. For
Figure 8 both images were generated by
Wombo Dream. For
Figure 9, the dinosaur woman was generated by
Leonardo. For
Figure 10, the main image was by
Whisk, overlaid by internal art from "Fair Exchange?" by
Connor Cochran. The colorized woman's face layered into the inset was generated by
Wombo Dream.
Next: Part 2 of a story about telekinesis.
Similarly, time travel as a plot element provides an author with a means to endlessly adjust Reality until any desired outcome of the story is achieved. Yes, you can get involved with various technical limitations on time travel or "time travel police" as ways of imposing artificial limits on time travel as a plot device, but none of those tricks has ever given me comfort. 
