Greetings, Mister Principal: The twin paradox

It only takes a genius to remember the address of this website in one second: (Dianping Chinese), the fastest updates! No ads!? "Wait a minute, Reiner, I have a question here."

At this time, Lanchester Stanion suddenly spoke.

“The time dilation effect will occur on objects moving at speeds close to the speed of light. According to the principle of relativity of motion, external observers can theoretically observe the object moving at the speed of light. Will external observers also appear? Time dilation effect?"

Your Excellency Stanion's words silenced the conference room again, and his question seemed to contain some kind of inexplicable weirdness.

"For example, there is a pair of twins, Al and Beta. They grew up at the same time and were exactly the same. At this time, Al obtained a spell that allowed him to leave the planet and go to the universe at the speed of light. He experienced a brief Accelerate and fly towards the universe at the speed of light. After flying for a period of time, it immediately decelerates and then returns at the speed of light."

Lord Stanion spoke carefully while considering his words.

"According to the time dilation theory, Al is moving at a high speed close to the speed of light. He should have experienced a time dilation effect. For one second that he has passed, Beta on the ground should have passed several seconds. If we do not add precise calculations, Discussion: Al and Beta were both twenty years old when they set out, but when they returned, due to the time dilation effect, Al looked only thirty years old, but Beta was already seventy years old."

After hearing Lord Stanion's explanation, several high-level mages present thought for a moment and nodded slightly, indicating that they agreed with this assumption.

"But now, let's think about it from another angle. If Al is used as the reference frame, then Beta has actually experienced the process of accelerating to the speed of light and then returning. Beta should also have a time dilation effect. From Al's perspective, Beta should act younger than himself."

"This creates a contradiction!"

Ludwig Stein quickly realized the problem. Due to the relativity of motion, the time dilation effect should appear on both sides, instead of simply dilating time on one side.

"Reiner, how do you explain this problem?"

Eagles Field is also puzzled. Lord Stanion's paradox is quite easy to understand, but difficult to explain, because it seems to conflict with the time dilation effect, and now, no one can Be confident in saying which one is wrong.

Everyone’s attention fell on Reiner, because among the high-level mages present, only Reiner, the proposer of the theory of relativity, understood this theory best. It was impossible for him to not consider this issue.

Reiner looked around at everyone, cleared his throat, and stood up.

"This issue is indeed under my consideration. My Lords, to be honest, the emergence of this twin paradox is precisely caused by the difference between the classical space-time system and the relativistic space-time system."

He waved his hand gently, and two small clocks appeared in mid-air.

“We can simplify the problem into two clocks that are originally consistent. One of them suddenly moves away at nearly the speed of light and then turns back, and the other stays in place. Find out what will happen to the displayed time of the two clocks after turning back. , in order to continue to simplify, we assume that the process of acceleration and deceleration almost does not exist. This is the result of two periods of uniform motion. The moving clock is called a moving clock, and the stationary clock is called a static clock."

Under the gaze of the mages, Reiner ordered the light spot to repeat this movement process.

"In the classical physics system, using two light points as each reference system, we can naturally get the result that the other party is moving at a uniform speed relative to itself, but let us focus on the point of this motion, that is On the moving clock, the process of the moving clock moving away from the static clock is obvious. Using the static clock as a reference, the moving clock experiences time dilation, and time passes more slowly. However, using the moving clock as a reference, the static clock also moves at a constant speed, and time appears. Expansion, time passes more slowly."

"Isn't this a contradiction?"

Mrs. Maria Instein asked doubtfully.

"But in fact, Mr. Einstein, the time of the moving clock and the static clock are relative. They themselves will not feel the difference in the passage of time, just like we will not feel the passage of time in the ruins. Whether it is faster or slower than outside, only after the two meet, their relative time comparison will be meaningful."

After Reiner explained this, he began to turn the distant light points back.

"The problem lies in the process of turning back. My Lords, from the perspective of the static clock, the moving clock is also moving at a constant speed, but from the perspective of the moving clock, the static clock is moving from behind itself in an instant. Moving in front of you is similar to making a 180-degree semicircular motion, and this motion exceeds the speed of light."

"Beyond the speed of light?"

Broly Augustine thought silently. Reiner's words seemed to be full of contradictions, but they also implied some facts that he did not say clearly.

"Of course, this behavior that exceeds the speed of light does not transmit any information. In other words ~IndoMTL.com~ If a moving clock can see things at infinite distances, at the moment it turns around, what is ahead is what it is looking at? If the static bell does not exist, to be precise, although the static bell exists, it is not within the light cone of the moving clock at the moment."

Liner's words caused a stir. This was something that high-level mages had never imagined. Compared with the scale reduction effect and the time dilation effect, the phenomenon mentioned by Reiner was even more incredible.

"We define the trajectory of a particle in space and time as its world line. The world line records all the positions of the particle from the past to the future. The range of this position is called the light cone. The range is determined by the speed of light. Objects cannot exceed the speed of light. Only things located within the light cone will have an impact on the object."

Reiner proposed a concept. At the same time, in mid-air, a light point zigzagged on the coordinate axis, forming a cone.

“For the moving clock, as it moves away, it will observe that the time of the static clock slows down. At the moment it turns around, the time of the static clock suddenly accelerates. In the process of returning, the time of the static clock continues again. Slow down until the two sides meet. At this time, the time elapsed by the moving clock is still less than the time elapsed by the static clock. In other words, Al, who flies into the sky, will be younger than Beta when they finally meet."

After speaking, Reiner demonstrated the phenomenon represented by his words. He drew two lines on a coordinate axis, one coincident with the vertical axis, and the other is an oblique line. On the coordinate axis, there are Two hyperbolas, the horizontal axis of the coordinate axis represents the space X, and the vertical axis is cT multiplied by the speed of light.

“The root cause of this phenomenon is that the moving clock and the static clock are in different world lines. In this coordinate system, the moving clock represents an oblique line, while the static clock represents a straight line. Clocks in different world lines cannot be equivalent through simple coordinate system transformation."