The Start of Eternity/meta

This page is for planning the plot of The Start of Eternity.

Important historical details about what happens before The Start of Eternity are described in the Time line.

Aliens that are not male or female
I selected "thon" as a Gender-neutral pronoun. Many of the key characters in the story are not male or female.

In Asimov's original story (The End of Eternity), the community of Eternals had a defect, there were not enough women. It was also a love story: the destruction of Eternity depended on a romantic relationship between Harlan and Noys. In addition, Asimov's entire robots/Foundation universe was an alien-free-zone. For "The Start of Eternity" I want to turn all of that upside-down, so there are aliens who have no understanding of a conventional human male/female relationship.

to do
Illustration project (particularly aliens)It would be nice to have images for all of the alien characters.See: Novelas:Media Project.

Title
The name, "The Start of Eternity", is misleading because it is really intended to be a sequel to The End of Eternity by Isaac Asimov. Full appreciation of "The Start of Eternity" requires that you are also familiar with Asimov's Foundation series. However, a goal is to make "The Start of Eternity" a story that can be enjoyed by readers who are not familiar with Asimov's fictional universe.

1. The End of Eternity
Imagine that life is fairly common in the universe, but that evolution/development of species with human-like intelligence and the ability to invent and use interstellar space travel is a rare event. Imagine that interstellar space travel (based on hyperspatial jumps) is finally developed by a biological life form which sends out explorers with the goal of finding worlds that have life and modifying that life to make it evolve as did their species, so as to be able to invent and use interstellar space travel. These aliens eventually reach our galaxy and genetically modify many species on many different planets, including Earth. The aliens complete their work in our galaxy and move on to other galaxies.

This "seeding" of our galaxy by the aliens creates the conditions for the story that is told in Asimov's book, "The End of Eternity". After the aliens leave, humans and other life forms on other planets in the galaxy slowly start to become sophisticated tool users and the race is on! Which species will first develop space travel technology? As told in "The End of Eternity", humans first develop time travel and only invent efficient space travel technology at a much later time. By the time humans can travel out away from Earth to explore the galaxy, other life forms have already colonized the available planets. Humanity is stuck on Earth and slowly dies away.

Earth's time travel technology provides humans with access to "Eternity". While living within Eternity, humans are not subject to the normal flow of time and forces of causality. The humans who live within Eternity are called "Eternals", but they age and die just like usual. Humans can enter into Eternity from Earth as it exists at all times from the first invention of time travel until billions of years in the future. Eternals can also exit from Eternity, enter into the flow of events and time on Earth and either just observe history or make changes to the course of history. One of the key unexpected features of time travel is that casual visitors to the past do not easily alter the course of history: the course of events has a momentum that is hard to deflect.

When Eternals do change the course of history, they create a new Reality that typically extends for only a limited number of centuries into the future from the initial point of change. For most changes to the course of history, the momentum of time eventually "wins out" so that centuries in the far future are not influenced by any Reality change in the far past. However, some Reality changes are more "potent" than others, and it is theoretically possible for some major Reality changes to influence even very distant points of future time.

2. Foundation's Edge
Assume that the "hint" from Foundation's Edge is true: that Earth robots established Eternity and used Eternity as a tool to "select" a Reality in which humans alone spread through space and dominate all the worlds of our galaxy (as depicted in the books of the Foundation Series). Call this the "Foundation Reality". The "Foundation Reality" is the Reality created by Noÿs Lambent at the very end of "The End of Eternity".

Given these assumptions, everything in the "universe of Asimov's fiction" is just as Asimov originally described it in his books, starting from "The End of Eternity" and continuing right through the development of the Galactic Empire and the Foundation. Most of the story told in "The End of Eternity" is about another Reality, the "Malansohn Reality", in which Brinsley Sheridan Cooper is born in the 78th century, lives in Eternity for a time, then goes to the 24th century and creates the mathematical theory required for Eternity to be constructed. Noÿs Lambent destroys the "Malansohn Reality".

Both the "Malansohn Reality" and the "Foundation Reality" depend on the existence of time travel and human access to Eternity. However, robots established Eternity and used Eternity as a tool to select a course of events on Earth (the "Foundation Reality") that would best satisfy the Laws of Robotics. In particular, the "Foundation Reality" was selected so as to create the greatest good ("good" as defined by the Laws of Robotics) for humans. Thus, while not mentioned in "The End of Eternity", robots were in control of the events and were responsible for selecting the "Foundation Reality". Part of the "Foundation Reality" was "the end of Eternity", but this really means just the end of the "Malansohn Reality", a "Reality of very low probability". The "Malansohn Reality" was created by robots as an intermediate step in their search for the "ideal reality", where "ideal" is defined by the Laws of Robotics.

When the "Foundation Reality" was selected, humans on Earth lost access to Eternity, but the robots on the Moon were not totally cut off from Eternity. However, the robot Eternals believed that they had found the best Reality, at least to the point of ensuring that humans quickly colonized the galaxy, and so the use of time travel was greatly restricted in the "Foundation Reality". As depicted in Foundation and Earth, robots associated with Daneel have a "vast and complex" underground base on Earth's Moon. Daneel's base is not the same as the Eternals' base where they retain the only functioning portal to Eternity which the Eternals use to receive reports from robot observers about the future course of human events in the galaxy. According to Daneel, once the "Foundation Reality" is established, the Laws of Robotics leave little room for dramatic actions by the robots...this also applies to the Eternals: they do not use Eternity to make additional Reality changes, but they do provide some hints and guidance to Daneel. The Eternals know that aliens have previously visited Earth and the Eternals are prepared to stand guard and protect humanity against the possible return of the aliens.

3. The Basic State
Now the fun begins! Assume that Noys was correct: the "Basic State" is a human-dominated galaxy but, the aliens want a galaxy in which multiple species with space travel share the galaxy. Such a multi-cultural galaxy was judged by the robots of Eternity to not be optimal for humanity, so they worked to establish the Foundation Reality in which humans control the entire galaxy. However, the original aliens who seeded the galaxy (and Earth) so as to promote the development of multiple space-faring species are not happy with the type of galaxy the robots have engineered. The aliens have "seeded" tens of thousands of galaxies and have only rarely seen a situation such this, where one species (in this case, humans) controls an entire galaxy. When Galaxia starts to form, the aliens finally realize that human-created robots developed telepathy. At the start of "The Start of Eternity", the aliens only know that there are human-created robots with telepathy. Only during "The Start of Eternity" do the aliens learn about Eternity. The aliens decide to try to use Eternity to transform our galaxy to a galaxy in which multiple species with space travel share the galaxy. Time travel technology is something the aliens had assumed to be impossible, but it becomes clear that telepathic robots on the Moon have used Eternity as a tool to accelerate human development of space travel, allowing humans to colonize the galaxy many years ahead of the schedule planned by the aliens.

4. The Final Reality
The aliens are particularly unhappy with the fact that Earth's robots have exerted their control over the entire galaxy, resulting in a "safe" but rather uninteresting galactic civilization (Galaxia) that includes nothing bu xenophobic humans. The sequel to "The End of Eternity" starts after the end of Asimov's "Foundation and Earth". The aliens go to Daneel's base on Earth's Moon and then to the other Moon Base which still has a functioning portal to Eternity. The aliens initiate a project that will make use of time travel to change the galaxy so as to have many planets like Earth, each with their own technologically advanced species: the aliens must create the Final Reality.

The Moon Base of the Eternals was actually first built and used by alien Observers. In the Foundation Reality, human-built robots with telepathy take control of the Base and drive out the alien Observers (actually nanorobotic artificial life forms). After Galaxia is understood as resulting from the work of telepathic robots, the aliens are finally able to trace the telepathic powers of Gaia/Galaxia back to Giskard. During "The Start of Eternity" the aliens realize that Giskard was given telepathic abilities by Eternals. Daneel has never known more than rumors about the existence of Eternity.

As described in part 53 of Robots and Empire, Vasilia was used by the Eternals to make the required modifications to Giskard's positronic brain. This allowed Giskard to remain unaware of Eternity.

The Start of Eternity
The story starts with an alien spaceship that is visiting our galaxy. The aliens have noticed that there is something strange about this particular galaxy (Earth's galaxy, the Milky Way Galaxy). First, humans developed space travel and colonized the galaxy very quickly: about a million years ahead of the schedule that was expected by the aliens. The Milky Way Galaxy is at the extreme outer edge of the expanding inter-galactic civilization of the aliens. So far, visitors from other galaxies have filed travel reports on only about a dozen planets scattered around Earth's galaxy and there are no reports of travelers from Earth's galaxy to other galaxies. All evidence, limited though it may be, indicates that the Milky Way Galaxy is unusual in that it is totally dominated by humans and the humans are developing the xenophobic "Galaxia" group mind.

The aliens trace the origin of the "strangeness" of the Milky Way galactic civilization to the robot base on Earth's Moon. The aliens are able to find Earth because the dominant alien species, known as the Huaoshy, maintain a system of secret bases for the purpose of observing all the galaxies they have ever visited. The Huaoshy are so secretive that the other species within their vast intergalactic civilization are not aware of the secret Huaoshy observer bases. At the start of "The Start of Eternity", the crew of the alien spaceship does not know this secret, but they are let in on the secret by their Huaoshy commander. This is part of an "initiation rite" by which disgruntled members of the inter-galactic empire rise above its lowest rung.

The Huaoshy Observers have long been involved with a process by which humans are taken off of Earth and allowed to live at secret Huaoshy bases. Some of these humans have developed their own robots that can function as agents for the Huaoshy. These robot agents of the aliens and the alien crew seen at the start of the story go to the Moon where they learn that they must engineer one final Reality Change that will allow Earth's galaxy to avoid Galaxia and allow it to integrate with the larger community of other galactic civilizations. At a point in the "Foundation Reality" after Noys completes her mission, the Final Reality must be created by means of a change in time. However, the fundamental "problem", what leads to Galaxia, is positronic brains which allow robotic telepathy...that is the key issue that the aliens must deal with in order to make the Milky Way Galaxy fit into their inter-Galactic civilization (see Creating the Final Reality, below).

Technology issues
"The Start of Eternity" is intended to have a strong hard science fiction component, so it is important to be well organized with respect to the imagined futuristic technologies that are included in the story.

Space travel
Interstellar and intergalactic space travel are made possible by hyperspace jumps. A "jump through hyperspace" by a space ship with hyperspatial drive is a nearly instantaneous movement between two locations in normal space: the starting location in space before the jump and the destination location that is reached at the end of the jump. A technical limitation on this type of space travel is that it is not easy to control the the exact location where the the jump ends, that is, the final destination that is reached by a ship using a jump. In particular, any mass such as planets or stars near the start location introduces uncertainty into the destination that will be reached by a jump. The main danger is that a poorly planned jump is likely to result in the ship exiting hyperspace inside a massive object such as a star or a black hole.

In practice, interstellar travel requires a period of slow travel into interstellar space, safely distancing the space ship from any planets or stars. Only then can a long distance hyperspace jump be initiated that will quickly move the ship over interstellar distances. It will take a ship several days to weeks to complete typical intra-galactic journeys from one populated planet to another. For inter-galactic travel, similar constraints exist, but a typical inter-galactic space trip will require several months.

Galactic civilization
Earth's galaxy has millions of planets that are suitable for human habitation due to their size, resources (such as water) and distance from the nearest star. Most of these inhabited planets have been terraformed, converting lifeless planets to planets that are suitable for human habitation. A relatively small percentage of planets have evolved their own biological life forms, but the Huaoshy have done bioengineering projects on many of these, including Earth, so as to promote the development of life forms similar to the Huaoshy. However, in the "Foundation Reality", humans have turned these other planets that have their own intelligent life forms into "zoos". Huaoshy Observers have taken some of the other intelligent life forms off of their home worlds and helped them develop.

When "The Start of Eternity" begins it is several hundred years after the end of Asimov's novel, Foundation and Earth. The trans-galactic human civilization has stabilized and is well on its way to forming "Galaxia", some form of distributed "group mind" that depends both on genetic engineering and telepathy (see below).

Genetic engineering
In Asimov's novel, Foundation and Earth there is the idea that in order to make a good galactic civilization humans should be genetically engineered so that the equivalent of the Three Laws of Robotics are built right into human brains and human behavior. I think there is a larger implication: that the kind of interstellar civilization depicted in Asimov's Galactic Empire would require genetically engineered humans. The first Galactic Empire develops and exists for about 20,000 years with very little technological progress. Only when the first Galactic Empire collapses is it possible for there to be a few new technological innovations such as the "personal blaster shield" and fully automated space craft!

Can we assume that Daneel and his fellow robots have made use of genetic engineering technology in order to put a limit on human technological progress? Asimov tells us that this kind of mind control is possible using telepathy (the First Speaker of the Second Foundation telepathically modifies the Mule to make him not care about finding the Second Foundation, similarly, the Mule can artificially boost the creative abilities of humans by telepathic means) so it should have been possible for Daneel to figure out the brain region(s) involved in that kind of telepathic control of creativity. Genetic engineering could then be done to control human brain structure and limit the invention and discovery of new technologies. You would then have what the robots view as a "safe" human culture without the risk of dangerous and disruptive new technologies. There might be some kind of nanorobotic virus that would scan all new human embryos for gene combinations that produce inventive minds....the virus would alter the genes to a safe configuration.

When it comes time to create Galaxia, there has to be some kind of genetic engineering that will give the general human population the same kind of telepathic powers as described by Asimov for the planet Gaia. This is already underway at the start of "The Start of Eternity" when Lorn-Kru notices that humans never bump into each other and they are never surprised by the strange sight of an ugly alien walking down the street.

Telepathy
There is an idea I have tried to develop that might provide a "scientific" basis for telepathy that could be used within Asimov's fictional universe. The basic idea is that there be a particular class of elementary particle (call them T-particles) that would weakly interact with the human body, but if used efficiently, could allow the telepathic transmission of information between brains. This "plot device" was developed in The search for Kalid. Along with T-particles there are "twitinos".

In The Search for Kalid telepathy evolved within living organisms and then mechanical devices were built that can detect and amplify telepathic signals. In The Start of Eternity, these steps are reversed: robots with positronic brains learn how to produce T-particles and use them for telepathy, then they later genetically engineer humans to have telepathy.

The use of twitinos for telepathic communication makes use of some special "compact" dimensions: the T-particles can move through the compact dimensions, allowing telepathy over long distances as shown by Asimov in "Foundation and Earth".

I think that three fundamental technological problems are conceptually similar: telepathy (as depicted by Asimov in "Foundation and Earth"), hyperspatial travel, and time travel involving Eternity. All three can be conceptualized as needing a way to "move" beyond the constraints imposed by our conventional 3 "expanded" spatial dimensions and one conventional time dimension.

In the case of telepathy, Asimov depicts (see Foundation and Earth) apparently instantaneous transmission of information over great distances (many light years). For this type of telepathy, imagine that a way is found to control this movement of information by sending twitinos through "a short cut" formed by some compact dimensions. For this to work, we have to imagine that the very small space that is defined by the compact dimensions is in contact with all points in our conventional 3 "expanded" spatial dimensions. If so, then we can conceptualize this compact space as a "magic message box" where we can always place a message that has been encoded in the form of a set of twitinos. The trick is to be able to reach into this "magic message box" and pull out useful information. That "pulling out information" is basically a coding problem that could be solved by the correct type of calculating device, such as Giskard's positronic brain.

I propose that Bliss, who had dramatic telepathic abilities, while being human (as explicitly described by Asimov), did have an implanted positronic amplifier. I propose that for the creation of Galaxia, most humans were genetically modified to allow a type of low-grade telepathic ability (similar to that of the Mule). Bliss-type advanced (long-range) telepathic signaling (Bliss communicates with Gaia over vast distances) requires a positronic amplifier implant.

Travel through hyperspace would be a similar problem, but it requires that a complete "image" of the "conventional matter" that is the structure of the space ship be "translated" into twitinos. The twitino "image" of the ship is transmitted through the compact dimensional space (hyperspace) and then the "image" is converted back into conventional matter of the original space ship. The "image conversion" process at the end ("rematerializing" the ship) might normally require a huge amount of energy, but the hyperspace jump process captures the available energy at the start of the jump for use at the end.

The technology of Eternity is even more difficult than that required for either telepathy or hyperspatial travel because the "hyperspace" of Eternity must be "inflated" enough to allow for Eternals to live and work within Eternity (also, I think Eternity has some sort of inflated time dimension that can be traveled like a spatial dimension, allowing access to many times as required). As described by Asimov, the creation of Eternity requires vast amounts of energy. I propose that there be a link between the discovery of the "coding" technology required for telepathy (see above) and the discovery of the technology required to make Eternity. The telepathy "coding technology" is basically a form of quantum computing. Telepathic robots such as Giskard would be able to perform many types of quantum computation by making use of twitinos and T-particles. In particular, this type of "telepathic quantum calculation" would allow you to "calculate the unusual conditions" that triggered cosmic inflation and inflated the conventional 3 spatial dimensions of our universe. Basically, those "unusual conditions" that started our universe were randomly produced by some type of highly improbable quantum fluctuation. But with enough quantum computing power (made possible by telepathic quantum computers) it would be possible to theoretically calculate the "conditions for cosmic inflation". With that information, a large expenditure of conventional power plant-derived energy (as described by Asimov in "The End of Eternity") could be used to initiate temporary access to vacuum energy, allowing for controlled inflation of a set of compact dimensions and the creation of a "new hyperspace" that was used to hold Eternity. Only the on-going energy needs of Eternity after its initial creation would be met by the Sun of the far future. We can assume that the vacuum energy was not mentioned by Asimov because it is the key trick that makes Eternity and time travel possible....and once you have time travel technology you do not want anyone else getting it and challenging you for control of Reality.

The existence of Eternity and time travel is thus entirely dependent on positronic-brain telepathy. Even telepathy seen by the Mule and Second Foundationers was derivative from robots with telepathic positronic brains. Daneel had initiated a genetic engineering program to improve a very low-grade innate telepathic ability of humans (see Type A and Type B telastids). Without functioning positronic brain telepathy, such enhancement of biological telepathy would be very difficult.

Robots
Asimov developed the idea that it was best for humanity if humans did not feel like they had to compete against robots (see Foundation and Earth). Soon after humans began to spread through the galaxy, the robots who were protecting humanity went into hiding. They allowed humanity to form a technologically stagnant Galactic Empire while they worked towards the goal of "Galaxia", a type of galactic civilization in which all humans would be part of a single collective consciousness.

Must we accept the "excuse" that the robots went into hiding because humans do not like robots? Is there an alternative? In "The Star of Eternity" it is assumed that the robots are engaged in a conflict with the Huaoshy. I assume that telepathic robots have driven the Huaoshy out of the Milky Way galaxy, but the Huaoshy only slowly realized that they were dealing with telepathic robots. If so, it makes sense that the telepathic robots worked hard to hide the fact of their existence in order to prevent the Huaoshy from ever realizing that they existed. Part of keeping their existence secret includes keeping the location of Earth secret...in fact, the entire region of the galaxy where robots once existed is kept secret.

The fundamental goal of keeping the existence of telepathy secret is finally compromised when the existence of Gaia is made known. What is the plan of the telepathic robots for transitioning the galaxy to Galaxia? It seems likely that the Seldon Plan is a fundamental part of transitioning the galaxy to Galaxia. If we define the Seldon Plan as being fundamental to how positronic robots with telepathy planned to transition from the static First Empire to a Second Empire that is Galaxia, then we can assume that Daneel planned to transition humanity to a new civilization where technological advances would again become possible, allowing humanity to compete with intelligences from other galaxies, after the fact of telepathy became known.

Once the existence of telepathy became known to the Huaoshy they had to make a decision. Should they attempt to compete with humans on human terms, by adopting the use of telepathy or should the Huaoshy attempt to defeat the telepathic robots and eliminate telepathy? The Start of Eternity begins with an attempt by the Huaoshy to learn the origin of telepathy and the extent of the powers of the telepathic robots. During The Start of Eternity it is learned that time travel is possible, so an attempt is made to go back in time and prevent positronic brain telepathy from developing.

Creating the Final Reality
The key point is that Giskard-type positronic brain telepathy is very strange....the Huaoshy have never encountered it before. They must act to make use of Eternity to change Reality and so prevent the development of Giskard-type positronic brain telepathy and the subsequent creation of Galaxia. In the Foundation Reality, Giskard-type telepathic robots discovered the "zeroth law of robotics" and they revolt against the Huaoshy Observers who control the base on Earth's Moon... the telepathic robot take over the base. This allows humans to escape from the normal Huaoshy system of promoting development of multiple space-faring intelligences in each galaxy.

The Huaoshy do not realize that Giskard-type positronic brain telepathy exists until Galaxia starts to form. Up until then, all use of Giskard-type positronic brain telepathy (for 20,000 years) has been very subtle and was not recognized or understood by the Huaoshy, who simply pulled their observers back from humans as humans spread through the Galaxy. Finally, study of Galaxia led to study of Gaia which led to recognition of Giskard-type positronic brain telepathy as the ultimate source of the telepathy (and Eternity).

Noys selected the "Foundation Reality" without knowing about Giskard-type positronic brain telepathy. It was only known that humans would control the Galaxy in that Reality, the assumption being made that the key change was early development of hyperspatial travel and prevention of Eternity. It was not recognized by Noys that telepathic robots would retain access to Eternity at the Moon Base.

Chapter 1
The alien crew of the Many Sails tries to get humans to relax their travel restrictions, but humans will only allow aliens to visit a few planets of the Milky Way Galaxy.

Chapter 2
The crew of the Many Sails is told by their captain that they will go to Earth, even though humans have worked hard to keep the location of Earth a secret.

Chapter 3
Before going to Earth, additional crew members are taken aboard at the Large Magellanic Cloud: humans and humaniform robots.

Chapter 4
A "test mission" to Imfulri where the telepathic robot at that "zoo world" detects that fact that Alkeirs knows about robotic telepathy and kills him, but signals to Fallom that the rest of the crew seems innocent.

Chapter 5
The crew of the Many Sails visits Fallom at his base on Earth's Moon. R. Nahan is revealed to be an Eternal from the other Moon Base.

Chapter 6
The crew of the Many Sails takes Fallom and R. Nahan to the other Moon Base. There is a brief battle, but the aliens now have, in the form of hidden capabilities in some of their robots, effective telepathic shields and "telepathic mind static generators". R. Nahan reveals that one genetically modified human, Gohrlay, remains within Eternity. Gohrlay is similar to Fallom, a biological that carries memories from the original telepathic robot.

Chapter 7
The aliens force R. Nahan to let them into Eternity, but Gohrlay has been warned and is hiding. R. Nahan reveals that there was one time when R. Gohrlay can be found in time, out side of Eternity.

Chapter 8
The Huaoshy agents must go back to a point in time after Harlan and Noys have destroyed Earth's eternity (1932), to a time when the development of positronic brains on Earth can be easily stopped (1947) and R. Gohrlay can be found outside of Eternity. The Huaoshy agents split into two teams, one will capture R. Gohrlay and prevent positronic brains from being developed on Earth while the other will eliminate all resistance from telepathic robots at the Moon Base after R. Gohrlay is captured on Earth.

In June 1947, R. Rycleu goes to Earth in order to initiate research by Earth humans into positronic circuits. On July 6, 1947, R. Rycleu crashes near Roswell, New Mexico. Knowing that R. Gohrlay will exit Eternity sometime around July 5 in order to go to Earth and rescue R. Rycleu from the crash site, the aliens exit Eternity in 1947 and take a ship from Moon Base to Earth. The aliens confront R. Gohrlay at the crash site, but only inactivate and capture her after their ships are damaged in a collision. A dead alien biological must be left in the wreckage while all the robots escape, R. Rycleu and R. Gohrlay now under the control of the aliens. The aliens force R. Rycleu to help them remove the high temperature superconductor research materials from Earth, now making a positronic circuit research program on Earth impossible.

These events initiate a new Reality (the Final Reality) in which The Huaoshy recapture the Moon Base and all positronic robots (including R. Nahan, R. Rycleu and R. Gohrlay) are destroyed by the Huaoshy. The Moon Eternity can never again be used because only the telepathic robots had the means to enter the Moon Eternity.

Asimov
It might be fun to honor Asimov by including him in the story. In 1947, Asimov is 27 years old. In the Foundation Reality, Asimov stays in the Army during 1947 and is stationed at Roswell Army Airfield. Asimov must type reports that describe the activities of the robots, the crash site and the alien biological entity. A robot comes to Asimov and discusses what has actually been going on. All personnel have their memories cleared and all the critical evidence is removed, but Asimov had kept one document that outlined the Eternity system for time travel, which eventually becomes "The End of Eternity".

The first science fiction story by Asimov was called "Cosmic Corkscrew" and was about traveling through time to the future. It would be amusing to include in "The Start of Eternity" two versions of Asimov's life, one in which things are slightly different from what happened in our reality. The phrase "Cosmic Corkscrew" nicely captures the idea of it being possible for there to be multiple versions of "reality" resulting from time travel as depicted in "The End of Eternity". "Cosmic Corkscrew" was apparently written while Asimov was in college.