- "My readings indicate you were exposed to an extra-universal material that destroys positive matter on contact, a substance known as antimatter."
- —Gideon to Barry Allen[src]
Antimatter or anti-matter is an extra-universal substance that destroys any matter on contact within the multiverse, having the ability to completely destroy a universe and erase it from existence. During the Anti-Monitor Crisis, a wave of antimatter, brought on by the malevolent Anti-Monitor, destroyed all Earths in the multiverse and killed all living beings within them, leaving only seven Paragons, seeking refuge at the Vanishing Point, as survivors.
Non-sapient species, such as animals, can easily pick up on incoming antimatter. Supergirl noted that all the animals in National City were going nuts before the antimatter even entered the solar system.
Its presence on Earth-TUD5 caused Jennifer Pierce to turn into pure energy against her will and enter a shared "safe place," between worlds, along with two other Jennifers from different Earths in the multiverse. Thus Jennifer of Earth-TUD5 was saved from the destruction of the multiverse while her doppelgängers perished. She later surfaced on Earth-Prime, hours after the Anti-Monitor was defeated.
According to Gideon, antimatter is an extra-universal material, meaning that it does not exist within the multiverse, which is mostly made up of matter; rather, antimatter exists outside it: in the netherverse - the antimatter universe. Cosmic beings originating from the netherverse such as the Anti-Monitor can manipulate antimatter and use it to obliterate entire universes.
In the Speed Force, barriers known as antimatter walls appear when an antimatter wave has a possibility of hitting on a specific date in the respective universe. This can bar a speedster's physical body from time traveling to that date and the few succeeding dates (such as when Barry Allen attempted to time travel to December 11, 2019, a day after a supposed crisis, but was ejected by the Speed Force). Though speedsters in their prime are able to beam their mind to those dates with less-lethal consequences, as opposed to inexperienced and/or old-aged speedsters. With the assistance of a machine such as a neural hyper-collider, which can harness neural electricity and transfer it across superluminal particles (also known as tachyons) to project one's consciousness across space-time.
Discovery and detection
- "For the past year, I've been detecting antimatter signatures across the multiverse. Now, we don't know their origin. But if my algorithm is correct, all Earths could be in danger."
- —Jay Garrick[src]
Between 2018 and 2019, Jay Garrick detected a number of antimatter signatures throughout the multiverse. By October 2019, he had marked multiple antimatter signatures on his map, as he detected them near Earths-2, 6, 7, 17, 21, 26, 32, and X.
When Barry Allen attempted to travel to December 11, 2019 in October 2019, an antimatter wall blocked his path, causing the Speed Force to eject Barry back to his native time period, and if not for his accelerated healing factor, the antimatter would've consumed him out of existence. The reasons for the antimatter's presence within the Speed Force were the impending antimatter wave to hit Earth-1 on December 10, 2019 and the uncertainty and numerous possibilities of future events.
In October 2019, the Anti-Monitor detected Mar Novu's presence on Earth-2. He test-fired the antimatter cannon, releasing a wave of antimatter on that universe; killing its population and ultimately destroying the universe. Though Oliver Queen of Earth-1 managed to escape back to his home universe.  This resulted in the loss of Team Flash's allies Harry Wells and Jesse Quick.
On the last few minutes of December 9, 2019, Nash Wells was tricked by the Anti-Monitor into opening the Nexus and thus allowing the Anti-Monitor Crisis to begin immediately on December 10, 2019. The antimatter cannon began releasing a continous antimatter wave, which destroyed Earths 9, 66, 89, and X. Though The Ray was briefly saved from Earth-X to help save the remaining universes.
The antimatter wave reached Earth-38 and destroyed Argo City first, leaving Clark Kent, Lois Lane and their son, Jonathan, as the only survivors. Although the quantum towers that Mar Novu had established held the wave at bay, the shadow demons of the Anti-Monitor attacked the quantum towers and eventually destroyed it, allowing the antimatter wave to destroy Earth along with the rest of the universe. However, thanks to the coordinated efforts of heroes from both Earth-1 and Earth-38, as well as L-Corp, the D.E.O., the governments of Earth, Harbinger, Novu, and Oliver Queen's sacrifice, 3 billion humans and aliens were able to escape to Earth-1.
Also, on December 10, 2019, the antimatter wave reached Earth-TUD5 and as a result, it destroyed the entire universe. However right before that, Pariah managed to teleport Jefferson Pierce/Black Lightning to Earth-1, leaving him the only survivor.
The antimatter wave continued to destroy universe after universe, until it finally reached Earth-1, not only killing the native lifeforms on its surface, but killed the Earth-38 refugees. After a brief battle against a Mobius-possessed Lyla Michaels, it consumed those on the Waverider time vessel as well, except the seven Paragons, whom Pariah teleported to the Vanishing Point before the multiverse was destroyed.
DC's Legends of Tomorrow
Crisis on Infinite Earths Giant
- Antimatter causes planets to have world-wide earthquakes even when outside their solar systems.
- Antimatter cannot reach spiritual planes of existence, like the Speed Force and Purgatory. Logically, Heaven and Hell would also be unaffected. The Fifth Dimension is also immune.
- In other words, only the Third Dimension multiverse is affected.
- Antimatter disrupts more complicated forms of magic, the stronger its presence is in the multiverse.
- Constantine noted that the ritual to restore Oliver's soul post-Lazarus Pit revival didn't work because of it.
- Although the Monitor seems to have something of an immunity to antimatter, as he was not killed by an antimatter arrow shot by Oliver, it did bring him to his knees and left him unable to bring Oliver back to Earth-1 until he was fatally injured, suggesting that antimatter weakens the Monitor but doesn't destroy him outright.
- "Well...the accelerator went active; we all felt like heroes, and then...it all went wrong. The dimensional barrier ruptured...unleashing unknown energies into our world. Antimatter, dark energy, X-elements—"
- —"Harrison Wells"[src]
- When Barry first suspected that other meta-humans besides himself had been created as a consequence of the S.T.A.R. Labs particle accelerator explosion and confronted Dr. "Harrison Wells" about what really happened that night, the latter mentioned antimatter as one of several theoretical substances created by the explosion. Whether this is the same form of antimatter that was later weaponized by the Anti-Monitor is unknown.
- Similarly, according to Supergirl, Kryptonian pods use antimatter to propel them through space. This so-called "antimatter" is likely not the same kind utilized by the Anti-Monitor though, considering that the Kryptonians on Argo City were caught unprepared by the antimatter wave, which wouldn't have happened were they familiar with this kind of antimatter.
Behind the scenes
- In the real world, antimatter is defined as the "antiparticles" of regular matter found in the universe. Particle accelerators around the world regularly produce tiny amounts, with only a few nanograms having been produced in total.
- In the DC comics, antimatter is an alternate form of matter comprised of antiparticles. It functions in direct opposition to positive matter and contact between the two will ultimately destroy the particles of both.