Pym Particles

Pym Particles are a group of subatomic particles that, upon exposure to a strong concentration, can increase or decrease the size of an object or organism.

Overview
Upon discovering them in 1962, Dr. Henry Jonathan "Hank" Pym, biochemist and future superhero, theorized that Pym Particles originated from a parallel dimension known as Kosmos. The hypothesis stated that when a subject is enlarged as a result of exposure to Pym Particles, matter is shunted from the Kosmos Dimension to this one, allowing for the subject to gain mass. Likewise, when a subject shrinks, their matter is shunted from this dimension to Kosmos.

Scientists, both contemporary and modern, have balked at this theory, arguing with Occam's Razor that there must be a simpler explanation for this phenomenon than the interdimensional transference of mass. Some think that Pym fabricated this explanation in order to be the only one with the secret to unlocking the power of the particles. It is now commonly believed that Pym Particles originate in this dimension and that Pym Particles change a subject's size by reducing the distances between the atoms that compose it.

Another remarkable property of Pym Particles is the way that size changes and other properties do not. A human being of average height, if changed to the size of an ant, can retain their strength and therefore retain the ability to knock a normal-sized person unconscious even at such a diminutive size. Likewise, this same person could be enlarged to four times their size and, instead of retaining their strength, be strong enough to crush a car under their foot. Modern science now widely accepts the hypothesis that Pym Particles seem to work on three axes: size, durability, and strength. One or more of these properties may change while the remainder stays the same, allowing for extraordinary physical alterations.

Frequent exposure has been proven to train the body so that it can naturally produce Pym Particles. However, it also seems to produce psychological instability, with symptoms such as mood swings.

The First Mists
The American government conducted multiple tests for various types of nuclear weapons, both offshore and on the American mainland, throughout the 1950s. Though the exact reason for this remains unknown, the extreme energy released from the more experimental, powerful bombs occasionally somehow activated many Pym Particles at once. They would then gradually collect until winds could carry them away, sometimes within a mist.

In 1954, one such mist made its way around New Mexico from tests in the desert area near the town of Alamogordo. The residents of an anthill colony in the area grew to enormous, unnatural sizes and then rampaged across the state and into Los Angeles, California, tearing apart anything in their path and killing numerous people before armed convoys finally exterminated many of them and killed their queens. Dr. Pat Medford, one of the myrmecologists present during these events, presciently stated, "When Man entered the atomic age, he opened the door to a new world. What we may eventually find in that new world, nobody can predict." Despite efforts by the military to completely wipe out the ants, some of them burrowed underground after these attacks, and it is believed that some still thrive in subterranean realms. However, there have been no similar incidents since the initial assault on Alamogordo, and it is unknown if there will ever be another such attack by the surviving giant ants and any progeny they may have.

Another such mist moved towards the coast of California from the Pacific tests in February 1957. Their only known impact on the region was on businessman Scott Carey, who was lounging on a yacht deck when the mist rolled across the sea. He faced full exposure to the mist, but nothing happened immediately. It was only after accidentally spraying himself with insecticide that a gradual shrinking effect occurred, possibly triggered by something in the chemicals. Starting at a height of 6 ft 1 in, he shrank in size over the next few weeks, an event that local news and scientists monitored after he and his wife Louise made their situation public. He disappeared shortly afterward, with Louise speculating that their cat ate him, but scientists believe that he may have gotten lost and/or reached the atomic level (and, if the Kosmos hypothesis is correct, he may have become even smaller).

Growing Concern
In October of 1957, which proved to be a terrifying year of attacks by giant humans and insects, Lt. Col. Glenn Manning was caught within the detonation area of the first plutonium bomb test at Camp Desert Rock, Nevada. He initially suffered from third-degree burns in 90% of his body and developed the more startling side effect of gradually growing to giant size. Army scientists raced to figure out how to reverse the effect, but hardly any insight into the phenomenon was gleamed from the Carey case earlier in the year. Manning grew to a height of over sixty feet, went insane, and terrorized the Las Vegas strip before the military shot him down at the Boulder Dam.

A similar catastrophe happened the following summer, when Hollywood socialite and heiress Nancy Fowler Archer grew to a height of fifty feet and stormed through the city. While it remains unknown exactly how she changed in size, local news program KRKR-TV had reported some days before her rampage that Archer claimed to have encountered a 30-foot-tall extraterrestrial (which Pym later theorized might have been a Kosmosian) in the desert. Dr. Isaac Cushing, her family physician, later told news reporters that before her change in stature he had been treating her at her mansion for mysterious scratches on her neck and possible radiation poisoning. A local sheriff managed to kill her, but not before she murdered her husband and his mistress, caused extensive damage to the city, and made headlines around the country.

The government had previously tried to downplay the Manning incident as a one-in-a-million event, but now that a celebrity had caused a public and widely-publicized disturbance in a major city, they soon came to realize the urgent need to understand how people's sizes could change. Military scientists looked into the research of the late Prof. Gerald Deemer, whose well-meaning efforts to solve world hunger using radiation resulted in a giant tarantula assaulting the small Arizona town of Desert Rock in 1955. They worked with Dr. Edward "Ed" Wainwright, a Department of Agriculture researcher whose irradiated crops, created in 1957 through a similar project, were eaten by a swarm of locusts that subsequently turned gigantic.

Progress was slow at first. For example, Prof. Art Kingman's research on another giant tarantula, which attacked a New Mexico town in 1958, was fruitless, especially with major variations in measurements of the spider's size at different times. In October 1959, Dr. Hugh Evans and Dr. Jess Bright, respectively an astrophysicist and nuclear physicist who were formerly involved in nuclear bomb testing, briefly shrank down to the size of ants after exposure to "cosmic rays" during a space mission as part of the first incarnation of the Suicide Squad. However, they were unable to explain how the cosmic rays caused them to change in size, nor how they grew back to their original height in a matter of hours.

The Breakthrough
In 1961 it seemed that a breakthrough had finally happened with the appearance of a new superhero who possessed the ability to change his size at will. Raymond "Ray" Palmer, Ph.D, professor and physicist at Connecticut's Ivy University, took the mantle of a 1940s costumed crimefighter with different abilities and called himself "The Atom." The government pressed him to show them the secret of his size-changing lens, but Palmer confessed that his powers come from a mass of white dwarf star matter he had found. He was still trying to understand it himself and could not provide much insight.While he was still a graduate school student in New York University, Hank Pym closely followed the news coverage of the Alamogordo ant attacks with great interest. As the madness of 1957 and 1958 unfolded, Pym decided to make discerning the secret to changing size his top research priority. Astonishingly, after years of experimenting, including studying radiation from one of the bombs for clues on an atomic level, he became the first to identify Pym Particles and discover their unique property. After testing on inanimate objects, he decided to test on himself and unexpectedly shrank himself to the size of an ant, far smaller than he intended. He found himself trapped inside an anthill and managed to return indoors and restore his height with his own intelligence and the help of a single sympathetic ant.

At first, he concluded that his harrowing experience led him to conclude that the size-changing serums he had developed were too dangerous, and he dumped them down the drain. Pym reversed his decision a few weeks later when he realized that even though a new scientific development may have frightening unintended consequences, it could still be of great benefit with the right applications. It also did not hurt his decision that this breakthrough establish him as a pioneer in a time of great scientific advancement. Moreover, he anticipated that the return of the Flash and Green Lantern and especially the rise of the Fantastic Four and Thor could signal a new age of superheroes, and his new discovery provided him the chance to fulfill his lifelong fantasy of becoming one.

The Rise of Ant-Man
Pym spent the next eight months designing a protective suit, perfecting the serums, training his size-changing skills, recording his discoveries, exercising and building muscle, and studying entomology. In September 1962, while working on a government-commissioned project to invent a gas that would provide radiation immunity (possibly after the radioactivity-related giant incidents from previous years), KGB agents broke into his lab and held him and his assistants hostage. Pym was forced to test his powers in action for the first time, including his new helmet that granted him basic communication ability with ants by manipulating electromagnetic waves. He managed to thwart the agents, and Hank Pym established himself as a superhero.

In 1963 he gained a partner, both professionally and for a while romantically, in Janet van Dyne, alias The Wasp. She was trained to manipulate Pym Particles to change her size and soon became able to produce them naturally. Pym and van Dyne were founding members of the Avengers and thus worked for the government under SHIELD, but after Tony Stark refused to give the military access to his Iron Man armor, Pym chose not to make public the secret of controlling Pym Particles, saying it only belonged to him and van Dyne. The closest processes that other scientists in government, espionage, and scientific organizations devised could only shrink objects for a limited time.

Soviet scientist and defector Dr. Jan Benes independently discovered the secret in 1966, but while escaping the Soviet Union with CIA assistance, he was shot and fell into a coma. In the efforts of a science team to clear the blood clot in his brain and awaken him, a counterattack by a saboteur on the team caused permanent brain damage and Benes, upon awaking, was unable to remember his formula. With his notes lost during the escape, his process was lost.

1970s to Present
In 1979, burglar and ex-con Scott Lang stole Hank Pym's Ant-Man suit in order to free Dr. Erica Sondheim from Darren Cross, founder of Cross Technological Enterprises, who had been keeping her prisoner. When he learned that Lang had wanted Sondheim to treat his daughter Cassie's heart condition, he recognized Lang as a hero and allowed him to keep the suit. In 1982, following another in a series of mental breakdowns and his divorce from Janet van Dyne, Pym retired from superheroics to focus on research. In 2006, a thief with less morals stole a newer Ant-Man suit from Pym: Eric O'Grady, a reconnaissance worker for SHIELD.

Additional Notes
~ While I ended up filling in some blanks and expanding on the ideas, it was redditor /u/ProfUzo who first connected Pym Particles to the events of ''Them! and The Incredible Shrinking Man''. This post would not exist without their original post on the /r/FictionMultiverse subreddit.