Hugh Everett III suggested parallel universes as one of the possibilities in 1954, and they've been extremely popular ever since. All of this is just a theory as far as science goes, but there are people going public every day claiming that they found slips between dimensions and managed to go to different worlds. These are some of their stories.
The Mystery of Ong's Hat
Ong was a man who claimed his hat disappeared in another dimension after he threw it in the air. There's a town in New Jersey by the name Ong's Hat where the story originates. It's a ghost town now. In Ong's Hat, the Institute of Chaos Studies was founded by three scientists. Legend says that they mastered interdimensional travel using the chaos theory and that they currently reside in a dimension that never developed human life, but is full of plants.
The Wrong Town
Carol Chase McElheney claimed that, on a drive from Perris to San Bernardino, she wanted to stop in the Riverside, her hometown. When she arrived there, she realized that the town was different even though it was positioned where Riverside is supposed to be. She left immediately. After a few years, she went back to Riverside to her father's funeral and everything was in its place again.
Another Dimension in Gadianton Canyon
Several Southern Utah University students were driving through Gadianton Canyon when the scenery suddenly changed. The desert disappeared, and fields were all around them. At one point, weird vehicles that were egg shaped and had three wheels started going after them. They escaped and, in the morning, nobody would believe them, but nobody could explain why their tire tracks disappeared for 600 feet in the desert.
Highway to a Different Dimension
In 1985, Pedro Oliva Ramirez was driving in Spain. This was not his first time driving the route. After one turn, he claims to have found himself in a weird highway he never saw before that. Unusual terrain and structures were everywhere around him. He heard a voice tell him he was teleported. Once he found the intersection, he began driving to Seville but ended up in his hometown. He tried finding the weird highway again but never succeeded.
Waking up in the Wrong Dimension
In 2008, a woman in her forties, Lerina Garcia, woke up in "the wrong dimension." Her clothes and little details in her home were different, the department she worked at was replaced with a different one, and her old boyfriend acted as if they were never separated. But the new boyfriend was nowhere to be found, even with the help of a private investigator. What's sad about this story is that the wrong dimension is ours, as Lerina never returned to her normal life.
The Country of Taured
In 1954, a man landed in Tokyo and a weird thing happened. His passport was from a non-existing country named Taured that was located somewhere around Andorra. Everything else about his story could be backed up, except the country he was in. People from immigration didn't know what to do with him, so they put him in a hotel. During the night, he completely disappeared and was never found again.
People from the Shadows
Shadow people are believed to be shadows of people from different dimensions. A woman claimed to have met a little shadow girl in Dorchester, Massachusetts some 20 years ago. She saw some shadows on her walls, and they would glide around her room during the night. They were going around her room until it was completely dark. To this day, she doesn't know what happened but believes to have encountered people from another dimension.
Teleportation of a Ship
There was a project decades ago that wanted to discover the technology to make ships invisible. They seemed to have succeeded when one of the ships went off the radar. The ship appeared on the coast of Virginia. A lot of people on the ship died and others lost their minds. There are beliefs that this project continued to develop, managing to teleport people without causing death and insanity.
The Beatles Still Exist on a Parallel Earth
There's a man who claims to have gone to a dimension where John Lennon and George Harrison are still alive. While he was chasing after his dog, he was knocked unconscious, and he fell and woke up in a weird room with a man named Jonas who took him to a different Earth to help him. He even claims to have brought a cassette tape from that dimension, called 'Everyday Chemistry' by the parallel Beatles and he uploaded it online.
There's a stone forest in Lima, called The Markawasi Stone Forest. The stones make human forms and what's really creepy is that there are stories about interdimensional travel in the region. A woman who was camping there found a weird cabin that she wanted to enter. Her friends stopped her at the moment the half of her body was inside. The half that managed to enter the house was left paralyzed and the cause couldn't be determined. Some believe that she entered to a different dimension partially, messing up her nervous system.