Can you see your entire life from a higher dimension?
Einstein’s Theory of General Relativity
Einstein’s theory of general relativity explained gravitational force or gravity and how it arises from the curvature of space-time from an uneven distribution of mass.
Note: Space-time is combination of 3+1 dimensions (3 space + 1 temporal dimension)
From this theory we understood everything from the motion of galaxies, our workings of our solar system, expansion of space and nature of black holes.
But there was one drawback, general relativity could not explain phenomena which happened at the quantum scale.
Enter the Standard Model
The standard model in particle physics explains three of the four known fundamental forces (excluding gravity) in the universe which includes electromagnetism and weak and strong nuclear forces. It has allowed us to find quarks, higgs boson and neutrinos which is further demystifying the secrets of the quantum world.
The Elusive Theory of Everything
Today, scientists are working to integrate general relativity and the standard model in a unified all encompassing theory know as the “Theory of Everything” or “Unified Field Theory”. This theory will explain physics at a large stage (think galaxies and solar systems) and quantum states seamlessly. An elegant equation describing all the pyhsical forces in the universe.
The Need for Higher Dimensions
Surprisingly in order to incorporate these four fundamental forces together (gravitational, electromagnetic, strong nuclear, and weak nuclear) the equations seem to be only solved once we go higher from the 4th dimension.
In 1993 physicist Gerard ‘t Hooft postulated the “Hologrpahic Principle” stating, “Information about an extra dimension is visible as a curvature in a spacetime with one fewer dimension”. For instance a hologram is a 3D picture placed on a 2D surface which gives illusion of curvature when an observer changes his viewpoint. Similarly, Hooft belives that fabric of space-time is really 5-dimensional.
Mathematician Theodor Kaluza and Swedish physicist Oskar Klein proposed the Kaluza–Klein theory in 1921 which suggested the possibility of a fifth dimension where electromagnetism and gravity could be unified.
Although the Kaluza–Klein theory fell out of favor with physicts in the 20th century it was revived by the emergence of string theory.
Enter Quantum Mechanics
String theory states that the fundmanetal blocks of nature are nothing but vibrating strings of energy. Mathematically for this to work 10 or more dimensions need to exist. In theoretical physics according to string theory (type I, IIA, IIB, HO, HE) there are 10-dimensions.
M-theory which which proposes energetic “branes” mathematically needs 11-dimensions to work.
While Bosonic theory (type closed, open) mathematically requires 26-dimensions.
As of now these are just hypotheses but scientists at the the particle-accelerator Large Hadron Collider (LHC) are conducting experiments to prove if there are indeed higher dimensions.
What Would Higher Dimensions Look Like?
By adding a right-angle to a dimension you create a new dimension. Each new dimension is orthogonal to the previous direction.
Dimension-1: The first dimension is length, a straight-line is a perfect example.
Dimension-2: Simply add a right-angle to your line and now you have height. A good example is a circle, square or triangle.
Dimension-3: Add another right-angle and you will add depth to the square or triangle. Now we have a sphere, cube or pyramid.
Dimension-4: The fourth dimension is a direction in 3-dimensional space. Simply known as Time. A tesseract or hypercube is an example of a 4-dimensional object unfortunately we cannot create or visualize it in our 3D space.
Closest representation of a tesseract
Dimension-5: So what is orthogonal to Time? This where things get interesting. In the 5th dimension we would call time “Imaginary Time”. Stephen Hawking explains this in his essay “The Beginning of Time” with the following quote:
“It seems that Quantum theory, on the other hand, can predict how the universe will begin. Quantum theory introduces a new idea, that of imaginary time. Imaginary time may sound like science fiction, and it has been brought into Doctor Who. But nevertheless, it is a genuine scientific concept. One can picture it in the following way. One can think of ordinary, real, time as a horizontal line. On the left, one has the past, and on the right, the future. But there’s another kind of time in the vertical direction. This is called imaginary time, because it is not the kind of time we normally experience. But in a sense, it is just as real, as what we call real time.”
Hypothetically speaking of course, if you could access the 5th dimension you would be technically able to see the past, present and future of everyone on Earth.
You would no longer be just a prisoner of the present moving from past to present. Just as you can see the starting point of a straight line and the ending point in 2D space. You would be able to see the start and end of time in 5D space.
As a 5-dimensional being you would be able to access food from people stomach just like you can pick up a pen from a desk. Unbeknownsest to humans in the 4th dimension you would literally be a God. Wouldn’t that be cool.
But this is very unlikely. Quantum physicists believe any dimension higher that the fourth dimension are subatomic at scale.
Are Scientist Studying Higher Dimensions?
Scientist now believe that all dimensions above the 4th dimension are very compact in scale. String theorists state that these dimensions could be curled up much smaller than a atom’s nucleus. In super-string theory this is represented by the Calabi–Yau space.
Calabi–Yau space
Today, scientists are studying gravitational waves and light from the collision of two neutrino stars 130 million light year ago (source).
When we look out in space the effect of gravity seems much weaker compared to light.
This has led scientist to believe that light may be constrained to 4-dimensions while gravity is leaking in these extra dimensions.
We also know that dark energy is causing accelerating expansion of our universe and that it might be hiding in these extra dimensions of space (source).
It might not be long before we can prove there really are extra dimensions to our universe.