Engineering Made Easy

In this video 4th dimension has been explained in detail. This video answers many questions like- What are dimensions, what we mean by the 4th dimension, how many dimensions are there according to different theories, Why we can not perceive higher dimensions, how we can visualize and represent a fourth dimension geometrically using the example of a four dimensional cube known as the tesseract.
We will also discuss, can time be considered as the fourth dimension? Here I have used different methods of dimensional analogy like cross section, projection and bounding volume to help you in visualizing and understanding the concept of the 4th dimension.
The video also covers how a four dimensional being would see the world and what amazing powers would be possessed by the 4th Dimensional beings.
Friends I have also included some very interesting examples to make this complex topic easy to grasp.

Before understanding the 4th dimension, it's necessary to know, what actually we mean by dimension?
Dimension of a point is defined as the minimum number of coordinates that are needed to specify that point in it.
four dimensional objects need 4 coordinates for their representation. 4th coordinate should be perpendicular to the other three coordinates.
Actually a four dimensional space is a mathematical extension of the concept of three dimensional space.
We can visualize the fourth dimension (4th dimension) by using different methods.
Here I will use various techniques like geometry, projection, cross section and bounding volume to explain you the concept of the 4th dimension.
But before discussing all these techniques of visualization, let's first know, how many dimensions are there according to different theories.
Superstring theory requires 10 spacetime dimensions while according to M theory there are total 11 dimensions. In Bosonic string theory spacetime is 26 dimensional.
But why we are not able to perceive higher dimensions?
Actually according to some studies extra dimensions may be "curled up" at extremely small scales. The scale is too small to be visible to current experiments. Therefore it is really very hard to imagine higher dimensions for our brains.
This 4 dimensional structure is called as the Tesseract. Actually tesseract is the four dimensional analogue of the cube.
The simplest way to represent a tesseract is by drawing two 3D cubes one encompassing the other on a 2D plane.
These two cubes are separated by an unseen distance.
Actually these 8 lines that connect the vertices of both the cubes represent a "single direction" in the 4th dimension, that we can not see.

Now I will Discuss is time a dimension?
In order to accurately describe the position of an object we need not just the spatial dimensions to tell it's location but also time dimension to know how that position changes with time.
Because nothing can move instantaneously in space without moving in time. For moving in space we need to move in time too.
Therefore time is a dimension.

Dimensional analogy is an important tool to understand higher dimensions.
It is used to study how (n - 1) dimensions relate to n dimensions and then inferring how n dimensions would relate to (n + 1) dimensions.

Suppose a 3D object passes through a 2D plane then what would the 2D beings see?
Actually two dimensional beings can not see anything that is above or below their 2D plane.
So when a three dimensional object passes through a 2D plane then the 2D beings would only observe the cross section of the 3D object cut by that plane.

As we live in a 3D world and have 2 dimensional retina. So actually we see only 2 dimensional projection of 3 dimensional objects.
It is our brain that can create a 3D model of the object using 2D input from our eyes.
In the same way 4 dimensional beings would have 3 dimensional retina so they would not be able to see the 4 dimensional object in its entirety.
3 dimensional projection of the 4 dimensional object will be formed on their 3D retina.

We can visualize the fourth dimension also by using bounding volumes.
As we know that two dimensional objects are bounded by one-dimensional boundaries, In the same way three dimensional objects are bounded by two dimensional surfaces.
So We may infer by applying the dimensional analogy that a four dimensional object is bounded by three-dimensional volumes.

Now I will discuss what superpowers a 4 dimensional being would have.
It would be possible for a person living in four dimensions to go back in time and change the decisions made by him in the past and start a new timeline.
it would be able to see inside the solid objects because that being would have 3D retina that can see the whole solid 3D object in its entirety including its internal structure.
It would not be possible for 3D beings like us to bound him. As he would escape from the extra physical dimension- the fourth dimension.

This video explains that reality is an illusion. What we experience with our sensory organs is not reality and everyone has his own reality. So it also means that your reality is different from my reality. The concept of illusion of reality has been explained by giving examples of Virtual reality movie, animals and consciousness. Observer’s paradox has also been explained here.
Have you ever seen a Virtual Reality movie or seen others watching it?
While watching the VR movie although you are aware that you are experiencing a
virtual reality but still your mind and body responds to it accordingly. On changing the movie your reality changes.
We think what we experience with are natural senses is the reality and the experience provided by wearable external sensors is an illusion. But now lets imagine what will happen if i embedded these artificial sensors in you, inside your body permanently. How will you differentiate what you seeing from what others are seeing? Now suppose this experiment is done on a group of people at the time of their birth. In this case there would be no way to tell them what is real or what is not.
Actually the term reality in itself is illusory. Because when we experience something with the external sensors attached we call it illusion but when these sensors are embedded in our body and become the integral part of the body itself then we call it the reality.
Did you get the point?
Ok let me explain it in other way now. We know there are many persons with physical or mental disability who see this world differently because of their impaired sensory organs like color blind persons. Isn't their reality different from our reality.
Nowadays it is possible to change the brain circuitry to make you see blue color as red color. Brain cells can be changed in such a way that you will see night during sunny day.
Actually our sensory organs collect the information from the outer world in the form of electrical signals. These electrical signals are carried to the brain. Now the brain interprets this information and creates our own reality.
This reality may be quite different for different persons as the interpretation of the electrical signals depends on our mental level, past experiences, beliefs, pre assumptions, age, s*x, cultural environment and also on our present situation.
Here I want to mention a quote by the Great physicist Albert Einstein, He said- "Reality is merely an illusion, although a very persistent one."
What we have discussed till now is the reality from the human's perspective. But to what extent the reality can vary if we see it from the eyes of other creatures present on earth. What only humans perceive can not be considered as the reality.
Do you know that we humans can only see in the visible range of the electromagnetic spectrum?
Frequencies which are lower than the visible range of frequencies like infrared, microwave, radio waves and also the frequencies that are above the visible spectrum like ultraviolet,
X-ray, gamma ray are beyond our visual senses i.e. eyes.
But our inability to see these lower and higher frequencies doesn't mean that they do not exist.
All we need to do is just to change our natural visual sensors or take help of more advanced visual sensors to see lower and higher frequencies.
Some creatures like snake can see in the infrared spectrum, as their natural visual senses are capable of doing this. Same thing is true in case of human ears. We can hear frequencies in the range of 20Hz to 20kHz. Frequencies lower and higher than this range can not be perceived by human ears. As this frequency range is for perfectly functioning ears, most of us even can not hear all the frequencies present in this range. As we get older we can not hear higher frequencies.
So here the reality is completely different based on the our natural sensory organs and age.
If we include other animals like bats in this competition then we are nothing in comparison.
Dolphins and bats can hear frequencies up to 100kHz.
All these examples and discussion prove that reality is not objective. It is actually subjective as It is different for everyone.
Not only this, a famous experiment in physics known as Young's double slit experiment shows that the reality depends on the observer. Consciousness of the observer can actually change the reality. This is called as the Observer's paradox.
In the young's double slit experiment it was observed that small particles like electrons, photons or atoms behave like particles when an observer is present to watch their behavior but in the absence of an observer, they show the properties of wave. Why these particles show the dual nature, is still a mystery. This experiment again shows that reality is not objective, it may vary just by observation.
Reality is not something, that is our there, it is created in our brains and with our consciousness.
What YOU think about reality? Do you still believe that reality is same for all.

This video explains Who am I? What is my True identity and where is consciousness located. After watching the video you will get answer to the most important question about yourself that who you are. The concept of consciousness or Soul has been explained here scientifically.
Am I Lalit Vashishtha? or a YouTuber? or a human body? Who am I? To whom this 'I' refers to. Is it my brain that is calling itself 'I'? Or someone sitting in my brain. Where am I present in this human body?
Friends, What can be more important and interesting than knowing about myself and my true identity.
We are always interested in knowing other people and other worldly things that's present outside but rarely look inwards and ask to ourselves, Who we are?
Some of us think that we are just human body made up of different elements; and the life is simply a game of harmones and chemical reactions. And after death these all reactions stop and the game of life is over for ever.
But now the scientists have found that the game continues even after we die. It's our mortal body that dies not the consciousness. It just leaves the body.
Let me tell you that, I am not talking about what's written in religious books. Actually it's been proved using quantum physics by world's renowned scientists. But how, we will see it later in the video.

We all are so habitual of using the word 'I', that we never think deeply about this most important question, who am I?

Friends, Now I will give you an interesting example. Please note, that I am using this example just to explain you the concept.
Suppose a doctor cuts the organs of a person one by one starting from his legs and hands. Then the person would say, you have cut my legs and hands. Now the doctor continues to cut the organs to make his body shorter and shorter. Even then he would say, you have cut most of the organs of my body.
Friends here the point is, where is this 'I' in the body, who is saying that organs of my body have been cut.

When I say it's my hand, its my heart, its my brain or its my body then what does this mean? It means there is someone inside your body, who is the owner of the whole body which is separate from the body. This is the reason we don't say, I am brain or I am body instead, we say it's my brain or its my body.
This statement is exactly similar to, when we say, this is my Shirt or this is my car. While sitting car, we never say I am car. Which clearly indicates I am neither brain nor any other organ of the body. I am someone, who lives in the body and use the body for different purposes.
Initially Scientists used to think, that all the emotions are generated from the brain but later they found, they were wrong.
Actually there is someone who is guiding and controlling our body with the help of our brain and is not the part of the brain.
After researches it has been found that there is a small space between pituitary gland and hypothalamus which is the location where our consciousness is present. It is the location where you are present in your body. And from here you use your brain to control your whole body as a machine.
Stuart Hameroff and Roger Penrose, who are leading researchers in the field of human consciousness now agree that
consciousness is nothing but the information stored at the Quantum level.
According to Roger Penrose and his team, this Quantum information is carried by "Protein based microtubules" which are structural components of the human cells. It is the subatomic level where this Quantum information is stored.
After death of a person, this Quantum information can exit outside the body for ever as a soul.
Researchers from the renowned max-planck-institute for Physics in Munich have also supported this idea of Roger Penrose.
This is the consciousness, what we call as the soul. It is the master of our body.
To make it easier to understand, you can think of the body as the car and consciousness or soul as the driver of the car. There is no problem when you know that you are a driver sitting inside your car and driving it.
But problem arises when because of ignorance the driver thinks that he is car not the driver of the car hence he forgets his true identity.
In the same way, you i.e. the consciousness is the driver of your body and uses it to perform all the body functions.
According to quantum physics our body is mortal but we are immortal. After death of the body the consciousness leaves the body and moves into another parallel universe. So the soul or consciousness is not the part of
our body. it's separate from the body or in other words you can say, it lives in our body.