1900: A physics genius wandering around Europe

Chapter 120 Explanation 1: Everything within the light cone is destiny!

Chapter 120 Explanation : Everything within the light cone is destiny!

Faced with Born's sharp questions, Einstein smiled faintly.

Fortunately, he was well prepared. A few months ago, he followed Li Qiwei's advice and carefully studied the angles from which the theory of relativity might be questioned.

As long as you anticipate the questioner's prediction, everything will be under control.

As it happens, Born's problem fell within the range of prediction.

So he looked around at everyone, with a confident smile on his face, and said, "Thank you very much for your question, Born. It's a very good question."

"The core of this thought experiment is actually the concept of [simultaneity]."

"In the system of Newtonian mechanics, all reference frames share the same time, and time is absolute."

“That is, if event X occurs before event Y in a certain reference frame, then event X occurs before event Y in all reference frames.”

"This is indeed consistent with our life experience and daily phenomena."

"But relativity doesn't think so."

"In the relative view of space and time, the concept of [simultaneity] itself is also relative and based on the reference frame."

"Different reference frames, different situations."

“A second that happens to you is not a second to someone else.”

"In order to explain the encounter of trains AB more vividly, I introduce the concept of [light cone] here."

As he spoke, Einstein began to draw a schematic diagram and explain it simultaneously.

"We can establish a coordinate system based on event 1, with the horizontal axis representing space and the vertical axis representing time."

“Because as time goes by, the space that the train passes through gets longer and longer.”

"So there will be a cone-shaped range map." As he said this, he marked the size of the cone on the coordinate system.

"Then the light cone below event 1 is the past light cone, and the light cone above it is the future light cone."

“The past light cone is defined as past events that have an impact on present events.”

“The future light cone refers to the impact of current events on future events.”

"At this point, draw the space-time position of event 2 in the coordinate system."

"It is clear that Event 2 is located within the future light cone."

“So, event 1 has an impact on event 2.”

"Only events that occur within the past light cone will have an impact on event 1."

"Events outside the past light cone cannot have an impact on event 1 due to the speed of light."

"Similarly, if we draw a coordinate system with event 2 as the center, then event 2 will have an impact on event 1."

"So, for people on the ground, people on train A, and people on train B, the light cone distribution is different for these three different reference frames."

"Therefore, the order of events is different within the light cone perspectives of the three people."

"In other words, everything within the light cone is destiny, and everything outside the light cone is nothingness."

"I hope my answer can solve your problem."

quiet!
silence!

Deathly silence!

There was a sudden silence in the venue.

Countless people were shocked and their mouths were wide open.

Even all kinds of strange symbols appeared on the forehead.

Except for a few people, most people just listen to the nonsense.

In fact, Einstein's schematic diagram is not complicated, and the mathematical derivation is not profound.

However, this conclusion, which goes against intuition and everyday experience, is still hard to believe.

Even physicists only roughly understand the logic.

Especially the concept of light cone made them rack their brains.

This idea is so genius, so bold and so magical!
Physics has always been a description of objective facts, but today they have discovered that the theory of relativity actually involves fate.

It feels like going back to the Middle Ages.

When did physics become metaphysics?

But they can't find a reason to refute it, because if you accept the view that time and space are relative, you will indeed come to this conclusion. Ordinary physicists are better, as long as they abandon Newton's view of time and space, they will have no problem understanding it.

The derivation of relativity is also logical.

Although it is hard to accept, this is the truth.

As for senior physicists, they fully understood Einstein's logic.

They found that, with this explanation, there was indeed no problem with the theory of relativity.

However, the less of a problem there is, the more they cannot accept it in their hearts.

Very contradictory.

At this time, Born stared at Einstein's schematic diagram with hawk-like eyes, his face full of admiration.

He felt that the other party was definitely a super genius, and not just lucky enough to meet Li Qiwei as rumored, so that he could publish the theory of relativity.

With this ultimate understanding, the opponent's physical intuition and strength are unfathomable.

Then, thunderous applause broke out at the scene.

Obviously, Einstein's powerful ability conquered everyone present.

At least on this issue, his theory of relativity is impeccable and completely subverts people's imagination.

Even Li Qiwei couldn't help but applaud vigorously.

The God of Love is indeed the God of Love. No matter how dazzling his achievements are, they cannot cover up his brilliance!
At this time, Lang Zhiwan suddenly asked another question: "Einstein, but if a baby is just born."

"According to your calculation method, as long as the speed is fast enough, in the eyes of others, isn't it possible that he hasn't been born yet?"

Einstein smiled and said, "I know what you mean. You are worried that the theory of relativity violates the law of causality, right?"

Lang Zhiwan nodded, and many people nodded in agreement, as if it did violate the law of causality.

Einstein smiled and said: "First of all, I can definitely conclude that the theory of relativity does not violate the law of causality."

"The law of causality that we know actually needs to be based on the speed of light."

"As far as the light cone theory is concerned, anything outside the light cone is meaningless to the observer."

“Therefore, causality must be understood from a relative perspective of space and time.”

"It involves slightly more complicated math, but it's essentially the use of light cones."

"Later, I will explain this situation in detail in the form of a paper."

"But I think this explanation should be enough to prove the correctness of the theory of relativity."

Now, except for ordinary physicists and above who can understand it without any obstacles, most people are starting to find it a bit difficult.

It’s actually a matter of habit.

If one day you suddenly discover that human eyes are the organs for eating, and the mouth is for seeing.

Then it will be very difficult to understand, and your subconscious mind will always think that the mouth is for eating, so your thinking will not change.

At this point, Einstein added: “I know that this conclusion is very inconsistent with everyone’s daily intuition.”

"But that's the nature of the world."

"In the final analysis, the foundation of the human body is too weak."

"Our eyes can only see a small part of the light spectrum, and our ears can only hear a small part of sound waves."

"We can sense temperatures in a very narrow range, and the sizes we can sense are limited to micrometers."

"We couldn't generate a lot of momentum and get a lot of speed."

"If we humans have organs that are able to detect the effects of high-speed motion, then it would be very natural to understand."

"But unfortunately, we have evolved to be a species adapted to slow movement."

"But fortunately, the human brain is not subject to any restrictions."

"This kind of thought experiment can be verified in our brains."

"I hope that future technological developments will create instruments that can measure high-speed motion, which will certainly prove my theory."

Everyone nodded silently, feeling awe-inspiring.