What is the key factor in traveling through time and space?

According to official details, the man suddenly appeared in the middle of busy Fifth Avenue in Manhattan, New York City, and was hit and killed by a car. The driver who caused the accident said that when he saw the man, his dazed expression seemed to be full of confusion and confusion, and that the man suddenly appeared in front of him without warning.

When the New York police investigated the deceased, they found that the man was about 30 years old, wearing a 19th-century style black coat and a wide-brimmed hat, and the clothes were very new. The police found some coins in his pocket, banknotes from the 1870s and a business card printed in his wallet with the name "Rudolf Fenz, Senior." Also found was a receipt for the receipt of the horse and a receipt for storing the package.

A man suddenly encountered a time and space vortex while walking, then disappeared, and then appeared strangely on the streets of New York City. The New York police knew that the whole thing was strange from the beginning of their investigation of this strangely dressed man, and they have been Want to know the true identity of this man, but no matter how you search, you can't confirm who he is?

Austria and Germany tried to find the man's relatives, but later the investigation also entered dead end. In almost despair, Rihn checked a copy of the New York City telephone directory from 1939, and suddenly discovered an important clue. There was a man named Rudolf Fenz, Senior, in the directory.

After interviewing Rihn, she learned that Rudolf Fenz Senior was her father-in-law. He suddenly disappeared while out for a walk one day in 1876. Despite an extensive police search, he was never found. However, his family has always believed that this kind-hearted immigrant from Europe will one day come back. They waited for many years and gradually died. Rudolf Fenz Senior was 31 years old when he disappeared. At that time, his son was only four years old, who was the old woman's future husband.

His time travel experience should be that he accidentally entered the vortex of time and space while walking, and suddenly jumped out of time and space inexplicably and came to the streets of New York in 1950. He was in a daze and confused. As a result, he suddenly appeared in front of the car, and the taxi driver had no time to brake and hit him to death... Time played a cruel joke on Fenz. It pushed him forward three-quarters of a century, just to let the high-speed A moving car hit him and killed him.