Physics says NO !

                             There are no spirits. We should all agree that human beings are physical entities made up of atoms. So any arguments of there being non-physical entities interacting with humans are very archaic and frankly garbage proposals. It only takes some basic reasoning to debunk the spirit hypotheses. If the entities were non-physical then how are they interacting with physical systems made up of physical objects? Even if they could interact with the physical, the evidence of instances of some non-physical forces meddling with the physical world are completely absent in the physics lab and exist only in the realm of the human psyche in the form of stories, literature, drama and some very unreliable eyewitness testimonies. The more modern and scientific argument advocating for the presence of spirits is as follows -    ‘ what if the spirits are made up of physical particles , but the particles are just not discovered yet ? We have been discovering new particles and forces ever since the beginning of physics, and what if these particles are just not discovered yet?’ This is great reasoning but ignorant at best.

               All the particles and forces that exist and function at the human levels are discovered and accounted for. There seem to be no gaps in the knowledge, the fabric is spill proof. How did we get here? the answer is - with the amazing technology called particle accelerators . Let me explain what happens inside one.  We have large particle accelerators where protons are smashed into each other near the speed of light. The high energy collision causes the protons to rupture and break down into smaller particles. These smaller particles are then studied for their nature and behavior . These particle accelerators, especially the Large Hadron Collider (LHC) at Switzerland work at energies of Several Tera electon volts (huge amounts). These amounts of energy so huge that some physicists were afraid that turning onn the LHC was going to create a black hole destroying the Earth!  . At those energy levels the protons were broken down so bad that even the Higgs Boson ( the smallest most fundamental representation of the higgs field ) was released and discovered. It was a testament to the accuracy and efficiency of the accelerators, the physicists and the engineers behind them. 

                    Even if there were more undiscovered particles and fields that are still to be discovered by even more powerful accelerators, those particles would be irrelevant to the functioning of the normal world anyways. All the forces and particles that influence and function at normal human level reality have been discovered and studied meticulously (as the power our current particle accelerators are already exceedingly enough). Sorry, but there are no spooky spirit particles reported anywhere. Even if more particles and fields remain to be discovered, their discovery would not change the understanding of the world at the human functioning level as their behaviour would not affect the functioning of human brains at normal ‘levels of reality’. 

               Now that we've clarified that human bodies and brains are simply complex physical systems made up of atoms, we can start to see how the nature of an atom relates to a complete human. Atoms do not have wants. They do not have wishes and choices. They do not make independent choices and decisions and willy nilly act in this universe. They simply behave how the laws of nature tell them to. This argument is easy for most people to understand. On the level of atoms, everything just seems to be small particles dancing whichever way the equations command them to . Now let's consider something a little more complex . take a simple object like a ball. It's a little more complex than a single atom but still when thrown, functions pretty straightforwardly. A ball’s motion, when thrown can very accurately be predicted using common math equations. You do not expect a ball to change direction or course mid-air based on its ‘desires’. Just like any physical object made up of atoms, it follows the discovered laws of physics ( the laws of motion in this case) . We can go from simple and basic to more and more complex objects maintaining the same reasoning. The same rationalization about the nature of the ball can be applied to gases, liquids, trees, bacteria, insects and ultimately humans. 

               If all these biological beings are simply made up of atoms then how do they appear to have so radically different properties like the ability to have wants, desires and will to act upon them? The answer is EMERGENCE. let me elaborate - Simple objects when coalesce together they can build up systems that seem to have very different properties, properties that emerge as a consequence. Let's look at the example of a liquid like, water. Water is a liquid made up of loosely bound collection of molecules which are in turn tightly bound collections of atoms. Liquids behave in very different ways than individual isolated atoms with completely new properties as a result . These properties include waves on the surface, density, fluidity etc. All these are new properties - EMERGENT PROPERTIES .When studying water , It is easier and more practical to simply only study these new emergent properties which seem to have nothing to do with the nature of singular atoms however,  it is necessary to understand that the properties emerged as a consequence of trillions of atoms sticking together , following their rules in the first place . Even if the emerged properties of liquids are very different from those of individual atoms, the properties cannot go on to disobey the basic rules followed by the atoms. They are still embedded in the same system; the same universe. New properties can appear and emerge, but they still have the basic constraints of the individual building blocks.

               Similarly human consciousness which has properties like the subjective experience (qualia), wants , desires and will; is an emergent phenomenon which emerged as a consequence of the coalition of atoms forming the nervous system .

               It is not a result of nonphysical entities meddling with the physical bodies and neither is a result of spooky undiscovered particles dancing in the brain . It is simply a consequence of a lots of atoms sticking together in complex intricate ways forming molecules, compounds, cells, neurons, nerves and the brain. This emerged phenomenon of consciousness has numerous properties which appear to be different from the way single atoms behave but these properties are in essence nonetheless properties of atoms; atoms , when they form these complex biological structures. You cannot go from a bunch of things that can’t make their own choices forming a system with the ability to do so . There simply is no rational explanation of how this would occur. It may act like it does but in reality it can’t. Just like individual atoms cannot make their own completely unpredictable choices, human individuals are devoid of this ability as well.  

               But hold on! If animals and humans are just like any other physical object, and they are essentially robots following a code , does this mean if we crack the code , we can accurately predict what every human being is going to do ? every person’s next thought , feeling , choices and hence every interaction that’s ever going to take place in the future ?

               This gives rise to the idea of determinism. A concept that had support from most philosophers and physicists for the most of the 19th and 20th century including Einstein. The idea is that just like atoms are determined to act in fixed ways, and so are cricket balls, and obviously so are humans; everything must be predetermined based on the initial conditions of the universe after the Big Bang. The motion of every particle, object, planet and their following interactions including every human action, choice, decision, thought; everything is predetermined based on the laws of physics and the initial conditions when the cosmic chain of events started , When the cosmic dominos started to fall . This was the prominent idea in the world of physics for the most time. ‘God doesn’t play dice with the universe’ said Einstein. It only makes sense.

            But If there are any astrology aficionados in the audience ;) , who want to extend the logic of determinism to people being able to make predictions about the future , This ain't your luck day either . There are several issues with the idea that the future of the world or the fate of people’s lives can be predicted as they are simply following naturalistic laws. 

               First of all the process of determining the fate of a human’s life using the understanding of physics and biology would be very very hard project even in a Newtonian deterministic universe . You would need to account for every single atom in the person’s body, Its interactions with the surrounding atoms , and use this information in a framework of complete and absolutely perfect theories of neuroscience . This would be a very hard computational task and such fast computers simply do not exist. To think that ancient people somehow figured out how to calculate this is just wishful thinking.

               Secondly our universe is not completely deterministic in the first place. As it turns out we do not live in a completely Newtonian universe. Newton’s views are great when dealing with normal objects from balls to airplanes, but the rules break down at the levels of atoms and also very large objects like planets. The Newtonian view point is not a complete picture of reality. As it turns out atoms behave probabilistically. According to quantum mechanics ( our best theory of reality so far ) there is always some uncertainty as to the behaviour of an atom. This does not mean the atom is making its own choices, it simply means we cannot perfectly calculate the behaviour of very small particles like electrons and protons. This idea was first proposed brilliantly as the Heisenberg uncertainty principle. 

                The Heisenberg uncertainty principle tells us that the reason we cannot predict the behaviour of an atom to a 100 percent accuracy even if we understand the laws it operates on is as follows - There is a fundamental limit in this universe which stops you from accurately measuring either the mass of a particle or its velocity , the more accurate mass measurement gets , the velocity measurement gets less accurate as a result . The smaller the size of the object being observed, the greater the effect the uncertainty principle has on the measurement. This is why we have no problem quite accurately predicting the path a soccer ball will take but can only probabilistically predict where an electron will land. Because you can never accurately know where a particle exactly sits in space or where it is going, you can only consider probabilities and hence every calculation of its future is a probabilistic one.

           This threw the idea of determinism out the window. As it turns out, god does play dice with the universe. Einstein was wrong!  Calculations about the fate of physical objects are not deterministic but instead are probabilistic in nature. This takes the discussion of the nature of human thought and action from a completely predetermined realm to a slightly probabilistic one.

               A lot of people took the uncertainty principle and ran with it, proclaiming that since everything is not determined or cannot be determined, this uncertainty is the free will. This was also implied by popular scientist Michio Kaku in the following big think video. 

                                  


             

The video is titled - Michio Kaku: Why Physics Ends the Free Will Debate

As you can see, what he says does not seem very well thought out. The facts and the stories are true, but the interpretation is simply not correct. The Heisenberg uncertainty principle doesn't work because of some limits to our inquiry by some divine cosmic law or a deity that protects free will. It’s very simple to understand with the following example- Every time you make a measurement, you interact with the system. If you want to see where the electron is, you have to shine a light onto it, to see. The light rays (photons) in the process of hitting the electron and bouncing back into your eye will move and change the position of the electron a little bit, making the measurement a bit incorrect. There is no way to measure something without interacting with it and interacting with it will always have an effect on the system, moving it or changing it ever so slightly causing uncertainties. Just because you cannot accurately measure a system and make 100 percent accurate predictions, does not mean that the system is now free to make its own choices. Sure, there is a wild card , but you can’t chose what’s on the wild card and when to play it . Replacing determinism with uncertainty doesn't prove free will, it just swaps fate for some amount of luck.

              To summarize - human brains are made up of atoms and atoms are unable to make their own choices. They do not have wants or desires, they work according to the laws and previous configurations of the universe. It would be unreasonable to assume that a certain configuration of atoms (The brain) would somehow give them the power to ‘decide’ or make conscious decisions . Quantum phenomenon like the uncertainty principle might point us towards thoughts and choices being more random or probabilistic rather than completely predetermined but still not consciously chosen anyways. Free will cannot exist because there is nothing in the universe that allows anything remotely like it to emerge. To think that Physical things can make their own choices, is therefore just plain silly!  

               

For those readers, closely following this series of blogs ( hi mom ) . there will be another follow-up discussing the implications of humans figuring out about the absence of free will and what impact this knowledge has on people’s behaviors and attitudes towards life.