In the opening scene of the "Interstellar" movie, Murphy in his childhood once complained about the presence of ghosts in his room, but was ridiculed by Tom, and his father Cooper obviously didn't believe it, but Cooper was still dissuaded by his father-in-law and patiently advised Murphy: If she wants to explain the unknown through science, then she must record more data, and then simulate the model, and then find out the pattern.

It is only in the second half of the story that the audience learns that Cooper is actually the ghost in Murphy's room.

When Cooper is trapped in the time tunnel and loses himself, and finally appears in a five-dimensional time and space, he can see the same scene in different timelines of Murphy's room, he can see the past, present and future, so Cooper tries to have a dialogue with Murphy in childhood through the time tunnel, leaving clues for Murphy, hoping that Murphy can take him home again.

As an adult, Murphy finally deciphered the code that his father had left in the room through the time tunnel, and solved the problem of saving the earth in one fell swoop, becoming a hero to save all mankind, and finally redirecting his father home.

In other words, Cooper's scene in the five-dimensional time and space is crucial to the core message of the entire film, and it is also the most difficult scene in the whole film.

For this scene, Christopher built the entire hypercube!

In general, the world as we know it is a four-dimensional space, that is, three spatial dimensions plus a temporal dimension, while a five-dimensional space-time has four spatial dimensions, which is also known as a hypercube. For most people, this is a very difficult concept to understand, and it is even more difficult to present on the big screen.

The double-negative company was tasked with bringing the hypercube to life with visual effects, and from an artistic point of view, they could represent the whole concept in a more abstract way, but Christopher, a director who constantly pushed the limits of visual effects, decided to do the work exactly as the hypercube looked.

Paul Franklin, VFX supervisor at Double Negative, spent nearly six months studying with astrophysicist Kip Thorne, and even got his hands on Kip Thorne's notebook to ensure that his production team was able to create images that fit the laws of real physics formulas.

The same goes for hypercubes.

At present, human beings still cannot understand the concept of the four spatial dimensions, so Christopher and Kip arranged for Cooper to fall into one of the faces of the hypercube, and then experience the hypercube from Cooper's point of view, so that the audience can feel the power of time and space in an easy-to-understand way

Because the faces of the cube are two-dimensional, the faces of the hypercube are three-dimensional, and Nolan's design of Cooper fell into the "three-dimensional face" of the hypercube, which made Cooper not lose his ashes.

At the same time, Murphy's room is located on another three-dimensional plane of the hypercube, because of the existence of five-dimensional space-time, which makes it seem that there is only one bookshelf between Cooper and Murphy, and the distance between the two people seems to be within reach, but in fact, the entire river of time and space is separated.

According to Albert-Einstein's theory of relativity, it is impossible to go back in time, even when entering a high-dimensional space-time. But the film shows that gravitational waves can travel through time and affect the past, which also means that if Cooper wants to change the past, he must be able to see the entire timeline, from the past to the future.

Time in the five-dimensional space-time is an entity, just like a thread, in which you can see every moment on the entire line from beginning to end, but if you try to change what happened in the past moment, you can only use gravitational waves to make hints and flap your wings like a butterfly effect.

To this end, Paul Franklin led the VFX team to think about what the hypercube should look like, especially how to show the linear time of physical existence, how to further use objects as a medium to show each moment on the timeline, he had to be ordinary to a perfect solution, not to make the picture chaotic, and he had to make sure that the audience could observe the changes in Murphy's room at different times above the timeline through Cooper's perspective.

It was almost an impossible task, but the double-negative company did it.

They shrunk the six images of Murphy's room and made each image emit two vertical lines, these two lines are called the "timeline", and whenever the timelines intersect, a room image is generated, just like a quadrant, and the intersection of the vertical and horizontal axes can form an intersection point.

Therefore, in the entire five-dimensional space-time, you can see countless lines, constantly intersecting to form countless images of the room, these images are placed on different vertical and horizontal axes, according to the quadrant coordinates can accurately read the specific time point, Cooper only needs to float along the timeline to the vertical or horizontal, you can see the past or future of Murphy's room.

Such a picture is something that takes time for any audience to understand and digest, and it is no exception for actors. If the actor doesn't even know what's going on, how can he accurately express his emotions? A green screen can do that, but it can't help an actor feel a real "time travel".

Then, the hypercube in front of me appeared.

The space in the center is the three-dimensional plane, where Cooper is, while the rest of the space is all Murphy's room, on different time coordinates.

There are now only five rooms, but in the later stages, these rooms will be expanded to an infinite number of them, revealing all the coordinates of the entire timeline.

Projectors are also used for actual shooting in the studio. The double negation company will project the images generated by the time change onto the surrounding curtain wall, so that not only the actors, but the entire shooting team can have an intuitive view of the timeline inside the hypercube

For example, the space directly above is when Murphy was five years old, the space on the right was when Murphy was sixty-five, and the space below was when Murphy was thirty years old. Etcetera.

In this way, the entire five-dimensional space-time is presented in front of the public in three dimensions, so that the camera team and the lighting team can understand how to choose all the shooting tracks, images and angles.

Of course, behind the scenes, digital effects had to be added to every frame of the scene, and the amount of work was unimaginable.

Christopher's insistence can be seen from the side: the combination of live action and special effects can not only affect the performance of the actors, but also the impact on the entire shooting team is immeasurable.

When filming Inception, Christopher built the entire corridor and installed it on a giant rotating machine, allowing Joseph Gordon Levitt to shoot the weightless fight in the corridor, and now Christopher has built the entire five-dimensional space-time, allowing Lan Li to complete a "time and space journey" on the movie screen.

Timothy exclaimed, "So...... All the models and props in the center are for that scene?"

It's just for a scene, but it concentrates the wisdom of hundreds of people, and the consumption of manpower and material resources is definitely not trivial.

Before today, Christopher had discussed the concept of five-dimensional space-time with Lan Li, and for this reason, Lan Li also specially learned from Matthew Dunlop, and had a basic understanding of many of the theories, and now he finally saw the entity, and after being shocked and surprised, another question appeared in his mind.

"And what about the lights?"

Lan Li's inquiry made Christopher cast a puzzled gaze For the lighting, Christopher will inevitably make adjustments according to the actual situation, so what else is the problem? Lan Li can only continue to explain.

"I mean weightlessness. When Cooper was in a five-dimensional space-time, he was weightless, right? That's why he was able to float up and down, reading information from different time coordinates. But if you just rely on WIA, how can you behave in a state of weightlessness? Not only will the body not appear light, but it will also look bulky. ”

When the actor is in a WIA state, the limbs are off the ground, and it is difficult to control his body, which also makes the influence of gravity further magnified.

In traditional oriental martial arts movies, the aerial effect of flying eaves and walls needs to rely on manpower to pull Weiya, which is a super difficult technical work, not that the master can't achieve such an effect;

This also means that the actors' movements are bound to become clumsy, and the lighting effects become extremely important.

After filming "Gravity", Lan Li also had a preliminary understanding of the creation of weightlessness effect, and the first thought in his mind now is lighting.

Christopher opened his mouth to answer, he thought he had already made a draft, but when the words came to his mouth, he couldn't help but pause, revealing a thoughtful look.

Christopher just stood there and thought for a moment, then turned and walked away...... Straight away.

Lan Li and the others stayed in place, blinked, couldn't react, and between looking at each other, Timothy cautiously asked, "Was the director angry and left?"

"Poof", all three of them couldn't help laughing.

Christopher, of course, didn't get, but went to find the lighting team and the VFX team, which was a very, very serious problem.

Generally speaking, the Weiya problem is handed over to the martial arts stunt team to be responsible, but "Interstellar" has no martial arts scenes, so naturally there is no martial arts stunt team, and now the Weiya problem is completely ignored. If Lan Li hadn't realized it, they would have had to wait until the filming started to find out the problem and then slowly adjust, which would be even more troublesome.