Multiverses or Multi Universes is a topic which is debated often by scientists. Multiverses are also called parallel or alternative universes. If Quantum Physics is properly understood, it does indicate the existence of multiple universes. Is this even possible? We have hypothesis, but there is little understanding of how and where the multiple universes exist.

It all began with the famous Schrodinger’s cat. This was a thought experiment created by Schrodinger, a Nobel prize winner physicist in 1920/30’s. A cat is enclosed in a box which contains a vial of poison attached to an atomic trigger. The atomic trigger can randomly trigger or not trigger the poison vial. If it triggers, the poison will kill the cat. If does not, the cat will be alive. One is never sure if the cat is dead or alive at any given time. Both possibilities exist. Only upon opening the box, one can confirm if the cat is dead or alive. Observation is a must. Both a dead cat and a live one has the same probability. If you find the cat is alive, some scientists suggest that the other possibility of the cat being dead is equally possible. The Schrodinger wave function indicates this possibility. This means that the scenario of the dead cat will happen in an alternative universe. If the cat is found dead in this universe, then in the parallel universe the cat will be alive. The idea of multiverses became popular with this interpretation of Schrodinger’s cat.

Frankly, it is an incorrect interpretation of the Schrodinger wave function. Even Schrodinger himself was not trying to show this possibility of alternative universes with the thought experiment of the cat. He was trying to show how the Schrodinger wave function superimposes and entangles with each other. To make a proper interpretation, it is important to understand the Schrodinger wave function correctly. We will do this without being technical.

A proper diagnosis of the wave function will show that we do live in a multi universe that too right in front of our eyes.  

Understanding the Schrodinger Wave Function

As Newton’s law of motion is the heart of classical physics, Schrodinger’s wave function is the heart of quantum physics.

A little bit of background on Quantum Physics. Quantum physics took off in the early twentieth century when they found that light had both a wave property and a particle property. Sometimes it behaves like a particle and sometimes like a particle. If this subject of quantum physics is new to you, you must watch the following YouTube video, which shows the famous double slit experiment. It highlights the strangeness of the light being both a wave and particle.  https://www.youtube.com/watch?v=Q1YqgPAtzho.

In this double slit experiment, light behaves like a wave and whenever a measuring device is added, light starts behaving like a particle. Strange but true.

In 1923 de Broglie, a French Ph D student (the only recipient of the Nobel Prize for a doctoral thesis) went further and confirmed that not only light or subatomic particles, but ALL matter had wave and particle properties. You, me, a molecule, a tree, planets, stars, galaxies everything in this universe has a wave property and particle property. The wave and particle are two sides of the same coin. Everything can be a wave or a particle. In 1925, Schrodinger formulated a complex equation to understand the ‘wave’ part of the particle/wave duality. Schrodinger’s wave equation is a generic equation which can represent all the possible wave functions in the universe.

Schrodinger’s wave equation represents a physical system consisting of the following two parts:

1. Observed system
2. Observing system.

Observed System: The Observed System is the wave function of objects which is being observed. In the double slit experiment as shown in the YouTube link, the observed system is the waveform of light which is passing through the two slits. If you think about it, the wave function is much broader and not limited to light. De Broglie confirmed that all objects in the universe have a wave property. That would mean that the double slit plate will also have a wave property, so does the measuring device and photographic plate. Everything in this universe has a wave property.

 Schrodinger in his thought experiment about the cat, was trying to highlight this wider impact of the wave function. In the cat experiment, the box has a wave function, the vial of poison has a wave function, the atomic trigger has a wavefunction and so also the cat. All these wave functions in this thought experiment entangle with each other to form a single wave function representing the full system.

Entangle means they are part of one system, and they interact with each other. This interaction means that the combined wave function has many different possibilities. The technical term for the different possibilities is superpositions. Superposition means that the system wavefunction has many possibilities. The wavefunction could become anyone of these possibilities. However, whenever any observation or measurement is made only one the possibilities will take effect. In the Schrodinger’s cat experiment there are many possibilities. The atomic trigger may activate or may not. The box may collapse, and cat will escape. The cat maybe dead or alive. All these possibilities are inherent in this combined wavefunction. We just gave one example how different individual waveforms entangle to create a system wavefunction. If you look outside your window, the waveforms of all the objects will combine to from a single system wavefunction of that view. If you now look elsewhere, the wave function of those objects combines into one system. The system wave function could be complex, but they will follow the Schrodinger wave equation.  

Observing System: The Observing System is the observer or a measuring device. The observer observes the observed system or the wavefunction. In the double slit experiment, the measuring device or camera is the observing system. In the cat experiment, the person opening the box is the observing system. When the observing system interacts with the system wavefunction, only one of the possibilities will happen. The wave function collapses and a single possibility from all the possibilities will take place. In the cat experiment, either the cat is dead or it is alive.

There is always a confusion as to what is an Observing System. Who is the actual observer? Can a measuring device have the capacity to collapse a wave function? Very unlikely. What is the inherent power within a measuring device to collapse a wave? If you think about it, the measuring device is also a wave function. It is also made up of sub-atomic particles. What is happening is that the wavefunction of the measuring device gets entangled with the system wavefunction of the Observed system. This way they interact with each other. Even the person opening the box in the Schrodinger Cat’s experiment is not the ultimate observer. This person is also a wave function. Okay a person is wave function, what about his brain. Even a brain is made up of cells and is a wavefunction. Where does this cycle end to find the real observer of any event?

The only logical place to find the Observer is within you. This Observer within you is the witness to everything happening around you. This Observer is not a wavefunction, it is the witness to the wavefunction. The system wavefunction has many possibilities. It will collapse in the presence of the Observer to one of the options to become ‘particles’. Still, the unanswered question remains – what and who is this Observer within us. Science has never attempted to answer this critical question. It must be answered because the Observer is a component of the Schrodinger wave function. Since science is unable to answer, it is best to look elsewhere. Fortunately, the teaching of Vedanta has a clear and precise answer to this question. Vedanta teaches us that the nature of the Observer within us is like a bulb of Awareness. This bulb keeps shining Awareness. If you want to read and learn about Awareness, please read my post ‘Analyzing Awareness’. When the system wavefunction comes into the presence of Awareness, the system wavefunction collapses to become particle or object you are aware of. Awareness collapses the wavefunction and witness within you observes it.

Composition of the System Wave Function

The system wave function is much more complicated than what we have discussed. We will see that ultimately there is a single system wave function representing every possible object in this universe. Right from a single atom, to a living being, to stars and to complex galaxies. There is a single system wave function for the universe. We can call this the cosmic wave function. This cosmic wave function represents every object in the universe.

1. The Schrodinger wave function represents the energy profile of an object at any given moment. As time changes, the energy profile will also change. A new energy wavefunction is created with every passing moment. No energy wavefunction is lost. All the past wavefunctions are still available within the object wavefunction. All the past wavefunctions right from the birth of the object to this current moment combine to create a single wavefunction for the object. The object wavefunction is total of all the wavefunctions for the object right from its inception to the present time.

The energy profile of an object is a total of all the profiles since the birth of the object. For example, the sun is over 4.5 billion years old. The energy profile of the sun will include all the profiles for every passing moment. Every moment in time is part of the wavefunction for the sun. All these individual wave functions are combined to create a ‘grand’ wave function for the sun. As time passes, the new wave function is added to the cumulative profile of the sun.  In the sun’s cumulative wave function, the profile for each moment of the sun since inception is available.  

This cumulative sun wave function has the possibility to become any of the suns in the historical timeline. All the possibilities of the sun are available in sun’s wavefunction. How do we understand this? Let us take an example. You are on Earth; your friend is in Mars and your alien friend lives in a planet 5 million light years away. What happens if each one them looks at the sun at this ‘now’ moment? Light takes 8 mins to reach Earth from the sun, it takes 13 mins to reach Mars and 5 million light years to the remote planet. The total sun wave function is available to every observer. This sun wave function has all the possibilities in the historical timeline. Every moment is present in the sun wavefunction. When this wave function collapses in the presence of the observer, you in Earth will see the sun which is (now – 8 min) old. This is because, light takes 8 min to reach you, you will only see an older version of the sun, not the ‘now’ version. You will see the (now minus 8min) version of the sun. This (now minus 8min) version of the wave function is present within the cumulative sun wave function. For your friend in Mars, the wave function which is (now -13 mins) will collapse so that he can see the sun which is (now-13 min) old sun. Your alien friend will see a very ancient sun. He will see (now – 5 million years) old version of the sun. Each one of us is seeing a different version of the sun. All these different versions of the sun are available in the cumulative wave function. Even if millions of people are looking at the sun right ‘now’, each one of them will collapse one of the versions of the sun.    

We just seen the example of the sun with all the historical wavefunctions. This will apply to all the objects in the universe. Every object in the universe is a cumulative wavefunction of every moment in time. Your wavefunction will be a total of all the wave functions since your birth. The trees, cars, planets, galaxies each one them will have a time wise total wavefunction.

2. To add to the complexity to the wavefunctions, each object in the universe with its own cumulative wave function will all combine to create a one big wavefunction for the universe. We can call this the cosmic wavefunction. This cosmic wavefunction includes everything which is contained in the universe. Nothing is left out.

3. A single cosmic function which contains every object in the universe since the start of time, which is the big bang. It is not easy to grasp this. How can a single waveform represent everything? How does each object’s wavefunction keep its own identity within the cosmic wavefunction? It is not an easy question to answer. A good analogy to answer this question is Google Maps.  We use Google maps often and it has the road map of almost the entire world. The central server stores the software content for Google maps. This one single server has the information of all the required content. If you are in New York, you will see the maps of that city, if you are in New Delhi, you will see the maps of that area.

In many ways, this centralized software code is like the cosmic wavefunction. Both are one big bundle of information. The cosmic wavefunction is much more complicated and extensive. It contains the entire universe and keeps the historical information of all the objects.

4. Vedanta teaches us that there are ‘mental waves’ or ‘vrittis’ in the mind. These mental waves represent different objects. It is important to understand that these mental waves or vrittis are made up of Knowledge. Yes, Knowledge or intelligence. This intelligent wavefunction knows what object it represents. Please think and reflect upon this. Knowledge or intelligence is the substance of the wavefunction. This is a great insight because it will help understand the object wavefunctions we have been discussing. Even if all the object wavefunctions combine to form a single cosmic wavefunction, knowledge of each object is maintained. It is not wrong to say that the cosmic wavefunction or mental waves is the total knowledge repository of the universe. Total knowledge or intelligence of the universe is present in the cosmic wavefunction. The knowledge or wavefunction of an object can be found within the cosmic wavefunction. Just as Google Maps has the coding to keep track of all the roads in the world, the cosmic wavefunction has coding to keep knowledge of all the objects in the universe.  

5. Another important conclusion which can be made is that the cosmic wavefunction operates only within the mind. Quantum physics has shown that matter has both wave and particle properties. We see and know that the ‘particle’ is the universe we see out there. But quantum physics rarely discusses the wave part. Where does it reside? The Wave part of the wave/particle duality is largely unknown. If you are a student of Vedanta, you will learn that the only place where the wave part of objects can reside is in the mind. It is the same as the mental waves or ‘vrittis’ as indicated by Vedanta. And these object wavefunctions are made up of knowledge or intelligence. If you have time, you must read my article ‘Vedanta and Quantum Physics’ where I have shown that the wave part of the object and mental wave or ‘vritti’ as taught by Vedanta are the same.

Multiverses

We just seen that the cosmic wavefunction is a one big wavefunction. It is a combination of all the objects in the universe. In this cosmic wavefunction there are a great number of possibilities.

• The possibilities could be a combination of any number of objects. It does not matter if it is a large or small combination of objects. For example, if you look out of your window, you will see one possibility which is combination of many objects. You look away from the window, which is another possibility where you will see a different combination of objects. In this way, the cosmic wavefunction can be ‘sliced’ into many different parts. Each ‘slice’ which you see is a possibility.  
• Within each object, there are many possibilities – the historical wavefunctions for that object since its inception to this moment. Each one of these historical wavefunctions is a possibility. The sun wavefunction has 4.5 billion years of possibilities. For each moment, the sun has a unique wavefunction. We saw earlier how 3 people saw 3 different possibilities of the sun from different locations.

Combine the above two and you will have an unlimited number of possibilities in the cosmic wavefunction. Each of these unlimited possibilities can be sliced out from the cosmic wavefunction. We will show that each of these possibilities within the cosmic wavefunction is a universe by itself. Since there are unlimited possibilities, there could be an unlimited number of universes.

We have seen earlier that in the presence of an observer the wavefunction must collapse to take up only one of the possibilities. Only one possibility can take root from the unlimited possibilities. Before understanding which possibility, do you think there is only one Observer? Is there only one observer in this universe? I am sure you will agree the answer is No. Each one of us is an observer. You are an observer, I am an observer, every human being is an observer. Besides the 8 billion human beings, there is huge population of animals and insects. Many of them also have eyes, so they must be observers. These are the observers on Earth. If you believe there are living beings in other planets, then you will need to add those observers to the total number of observers. The conclusion is:  there is a gigantic number of observers!

We have seen earlier that the cosmic wavefunction operates within the mind only – in fact in the cosmic mind.  The cosmic mind is the total of all the minds. Add up all the minds and you will get the cosmic mind. Within every individual mind there is an observer. From the total cosmic wavefunction, each mind will choose a subsection or part of the cosmic wavefunction. Every mind will choose a different subsection.

1. Let us take an example of a single mind. This mind will choose one possibility, which is a subsection within the cosmic wavefunction. This subsection is a combination of different object wavefunctions. We have seen earlier that these wavefunctions are made up of self-knowledge. The wavefunction knows what objects it represents. In the presence of the observer in the mind, this knowledge in the wavefunction takes root to become the various objects. Quantum physics will call this the collapsing of the wavefunction to a single possibility.

One of the possibilities within the cosmic wavefunction has collapsed to become the universe this mind sees. This universe is created by the observing mind. It will not be wrong to say that this universe belongs to this mind. We will shortly see that this universe is not shared with other minds. Each mind has their own unique universe. As time passes, there is a constant change in the universe. New and different subsections of the wavefunction will keep collapsing in this mind and the mind will witness a changing universe outside. This changing universe is unique to this single mind.

2. In the same way, all the available minds will choose a different possibility from the cosmic wavefunction. Each mind will have a different and unique subsection of the cosmic wavefunction. The objects are never the same in two subsections. Each possibility or subsection within the cosmic wavefunction is unique. A good comparison to understand this – cutting slices of a cake. All the cake slices will be unique and different. The same slice cannot be repeated. In the same way, each subsection of the cosmic wavefunction is unique. If one subsection is being used by one mind, another mind cannot use the same possibility or subsection. This way, each mind has a unique subsection of the cosmic wavefunction.  

The observer in each mind will collapse a unique subsection. When this wavefunction collapses, the mind will witness the objects contained in the wavefunction. Since the subsection is unique and it is not repeated, each mind will create a different and unique universe. From the Schrodinger wavefunction point of view, each mind is collapsing a different possibility. Each mind is creating a different universe. No two universes are the same. There is a gigantic number of minds, each mind is creating their own unique universe. Multiverses are being created by each mind.

3. It is easy to argue that we are looking at the same objects in the universe. How can each mind look at different set of objects? If you and your friend are looking at a bunch of trees, you will both say that we are looking at the same objects, how can they be different? Let us analyze this further to show that you and your friend are looking at different versions of the same objects. The objects may look the same, but you are looking at different versions of these objects.

• Different object distances – If your friend is standing 10 feet ahead of you. Light is going to take less time from the trees to reach him and a bit longer to reach you. Since light is taking a bit longer to reach you, you are seeing an older version of the tree, while your friend is seeing a more current version of the tree. The two versions are not the same. The different is so minute that the human mind cannot see the difference, but they are different. Even if you are few millimeters apart, the version of the objects is different. As we have discussed earlier the object wavefunction keeps a history of all the wavefunctions since inception. Your friend’s subsection wavefunction will have a more current version of the trees. Your subsection wavefunction will have an older version of the tree. This way your wavefunction is different from your friends wavefunction.
• Same object distances: You could argue, you and your friend are standing at the same distance from the trees. The question then is: are you still looking at the same trees? The distance may be the same, but you are at different spots. This would mean the angular view to the trees will be different. You and your friend will see a different view of the trees. The difference maybe small, but still there is a difference. You will see the same view only if you and friend occupy the same spot. This is impossible. You cannot occupy the same spot in space. There must a difference. This not only applies to trees and other objects around us, but also to distant objects like the sun or stars. The angular view of these far away objects will never be the same unless and until you occupy the same space as your friend. This is not possible. So, we see that the subsection wavefunction for each person would be different. 

 So, two minds can never have the same subsection wavefunction. When these subsection wavefunctions collapse in the presence of the observer, each person will see different set of objects or different versions of the same objects. They can never be the same. This way each person creates and sees their own universe.  No two universes will be the same. This does make sense; we can only see what we see. We have no clue what other people perceive or see.

So, multiverses are a reality. This fits in very well with the Schrodinger wavefunction. The Schrodinger wavefunction states that a wavefunction has multiple possibilities and in the presence of the observer or measuring device, it collapses and only one of the possibilities takes root. The other possibilities could also take root, but it must happen in a parallel or alternative universe. This sounds mysterious, but having the read the above, it should make perfect sense!

To sum up, in our discussion we have seen that there are multiple observers – each living being is an observer. There are a gigantic number of observers. Each observer collapses one of the possibilities from the cosmic wavefunction. Each possibility is a subsection of the cosmic wavefunction. Each possibility is unique and different, it cannot be the same. Each possibility, or each observer creates a different universe. All these different or parallel universes are present right here. As long there are multiple observers, there will be multiple universes. It is not that mysterious as it sounds.