Physics rules out the presence of "Soul", "Ghosts", and "Afterlife"

Brian Cox and Sean Carroll have dissected the concepts of soul, ghosts and afterlife.

Short story: Physics rules out the presence of "soul", "ghosts", and "afterlife".

Reason in brief: If the soul has to be present and driving our body functions, it has to be interacting strongly with matter, which our bodies are made of. We know very well, to a high degree of precision, how the particles of matter behave, which our bodies are made of, at the energies of room temperature. This knowledge rules out the presence of any other 5th force that interacts with matter at these energies.  A similar argument can be extended to ghosts and by extension afterlife is ruled out.

Sean Carroll

"Claims that some form of consciousness persists after our bodies die and decay into their constituent atoms face one huge, insuperable obstacle: the laws of physics underlying everyday life are completely understood, and there’s no way within those laws to allow for the information stored in our brains to persist after we die. If you claim that some form of soul persists beyond death, what particles is that soul made of? What forces are holding it together? How does it interact with ordinary matter?
Everything we know about quantum field theory (QFT) says that there aren’t any sensible answers to these questions. Of course, everything we know about quantum field theory could be wrong. Also, the Moon could be made of green cheese.
Among advocates for life after death, nobody even tries to sit down and do the hard work of explaining how the basic physics of atoms and electrons would have to be altered in order for this to be true. If we tried, the fundamental absurdity of the task would quickly become evident.
Even if you don’t believe that human beings are “simply” collections of atoms evolving and interacting according to rules laid down in the Standard Model of particle physics, most people would grudgingly admit that atoms are part of who we are. If it’s really nothing but atoms and the known forces, there is clearly no way for the soul to survive death. Believing in life after death, to put it mildly, requires physics beyond the Standard Model. Most importantly, we need some way for that “new physics” to interact with the atoms that we do have.
Very roughly speaking, when most people think about an immaterial soul that persists after death, they have in mind some sort of blob of spirit energy that takes up residence near our brain, and drives around our body like a soccer mom driving an SUV. The questions are these: what form does that spirit energy take, and how does it interact with our ordinary atoms? Not only is new physics required, but dramatically new physics. Within QFT, there can’t be a new collection of “spirit particles” and “spirit forces” that interact with our regular atoms, because we would have detected them in existing experiments. Ockham’s razor is not on your side here, since you have to posit a completely new realm of reality obeying very different rules than the ones we know.
But let’s say you do that. How is the spirit energy supposed to interact with us? Here is the equation that tells us how electrons behave in the everyday world:
i\gamma^\mu \partial_\mu \psi_e - m \psi_e = ie\gamma^\mu A_\mu  \psi_e - \gamma^\mu\omega_\mu \psi_e .
Dont’ worry about the details; it’s the fact that the equation exists that matters, not its particular form. It’s the Dirac equation — the two terms on the left are roughly the velocity of the electron and its inertia — coupled to electromagnetism and gravity, the two terms on the right.
As far as every experiment ever done is concerned, this equation is the correct description of how electrons behave at everyday energies. It’s not a complete description; we haven’t included the weak nuclear force, or couplings to hypothetical particles like the Higgs boson. But that’s okay, since those are only important at high energies and/or short distances, very far from the regime of relevance to the human brain.
If you believe in an immaterial soul that interacts with our bodies, you need to believe that this equation is not right, even at everyday energies. There needs to be a new term (at minimum) on the right, representing how the soul interacts with electrons. (If that term doesn’t exist, electrons will just go on their way as if there weren’t any soul at all, and then what’s the point?) So any respectable scientist who took this idea seriously would be asking — what form does that interaction take? Is it local in spacetime? Does the soul respect gauge invariance and Lorentz invariance? Does the soul have a Hamiltonian? Do the interactions preserve unitarity and conservation of information?
Nobody ever asks these questions out loud, possibly because of how silly they sound. Once you start asking them, the choice you are faced with becomes clear: either overthrow everything we think we have learned about modern physics, or distrust the stew of religious accounts/unreliable testimony/wishful thinking that makes people believe in the possibility of life after death. It’s not a difficult decision, as scientific theory-choice goes.
We don’t choose theories in a vacuum. We are allowed — indeed, required — to ask how claims about how the world works fit in with other things we know about how the world works. I’ve been talking here like a particle physicist, but there’s an analogous line of reasoning that would come from evolutionary biology. Presumably amino acids and proteins don’t have souls that persist after death. What about viruses or bacteria? Where upon the chain of evolution from our monocellular ancestors to today did organisms stop being described purely as atoms interacting through gravity and electromagnetism, and develop an immaterial immortal soul?
There’s no reason to be agnostic about ideas that are dramatically incompatible with everything we know about modern science. Once we get over any reluctance to face reality on this issue, we can get down to the much more interesting questions of how human beings and consciousness really work."

Brian Cox

[Following is the transcript of the video. I recommend watching the video for better comprehension]

"So, here is my arm. It is made of electrons and protons and neutrons. If I have a soul in there, something we don't understand - different kind of energy or whatever it is. We don't have physics at the moment. It interacts with the matter because I am moving my hand around. So, whatever it is, it is something that interacts very strongly with matter. But, if you look at the history of particle physics in particular, which is the study of matter, we spent decades making high precision measurements of how masses behaves and interacts. And we look for example, for the fifth force of nature. We know four forces - gravity, two nuclear forces called weak and strong nuclear forces and electromagnetism. And that's what we know exists. we looked for another one with ultra-high precision and we don't see any evidence of it. So, I would claim that we know how matter interacts at these energies at room temperature. We know how matter interacts very precisely.

If we want to suggest that something else that interacts with matter strongly, then I would say that it's ruled out, I would go as far as saying that it is ruled out by experiment. It is extremely subtle and you would have to jump a lot of hoops to come up with a theory of some stuff that we wouldn't have seen when we observed how it interacts it with matter that is present in our bodies. Presumably, we believe in the soul that we wanted to exist outside, when you die, you might believe in ghosts and things like that.

If ghosts are something that carries the imprint of you presumably, it looks like you. So, that means that it interacts strongly with the matter that is you. Because it carries a pattern. If it carries a pattern, it carries information. If it carries information, there has to be an energy source to allow for that information and pattern to persist. Again, you end up with a theory that is postulating something that interacts with light. If you think a ghost is a soul, then it is something that people see sometimes. That means it interacts with light. But we know how light interacts."

Challenges to promote scientific temper in India

Promoting scientific temper in itself is a challenging task. Given that it aims to promote reason, the usual tools to manipulate emotions, that are used by several other movements aiming to promote new ideas, are not at its disposal.

Apart from some of these usual constraints, there are some emerging constraints to promote scientific temper, some of which are specific to India.

1. Using the vocabulary of science to justify superstitions: Earlier, the superstitions were rooted in tradition. Tradition gave legitimacy to superstitions. It is easy to address such superstitions. Now, it has been made complex by using the vocabulary of science to justify the superstitions. In this innovative approach, science (vocabulary) is used against science (scientific thinking)!

For instance, in olden days, people would just say that some things happen on the eclipse day. People are advised to follow some precautions like not eating food, taking care of mentally ill patients etc. This practice was rooted in tradition. Now, people use science vocabulary of gravitation, light etc. to justify these - the gravitation of the moon affects the liquid in the brain increasing the mental illness.

People who want to be seen on the right side, the side of science, but also cannot resist the appeal of the messengers of such pseudoscience are the victims. Such people are educated enough to know that this is the vocabulary of science, but not educated enough to see through the nonsensical claims. Once educated people start believing, even though for wrong reasons, it creates a broader social legitimacy for such superstitions.

It takes much longer than usual to debunk such theories as it involves explaining the nuances and details of the scientific theories. The problem is that people usually do not have such high attention span. It thus creates challenges in promoting scientific temper.

2. Associating superstition with religion: People associate superstition with religion. Once you associate something with religion, it creates several complications - it enters into a space of personal opinion which others ought not to criticize; criticism of superstition becomes an attack on the religion. The effects of the narrative of "attack on our identity" is fulled by an environment of a growing identity crisis in the world.

Astrology, the superstitions around eclipse and Vaastu are classic examples of this phenomenon. The killing of anti-superstition activists like Dabholkar is an example of people conflating the criticism of superstition with an attack on religion.

3. Falling prey to the pseudoscience of godmen preaching life lessons: Human life is difficult. People go through a lot of emotional turmoil. In such states of vulnerability, people turn to godmen for direction. Given that the godmen are good orators, they do provide some soothing. In order to experience this, one has to completely trust everything the godmen say. People enter into an all or none relationship with godmen.

As a consequence, this means that people also have to believe in the pseudoscience spread by these godmen. Linking it to the argument above, godmen have specialized in using science vocabulary to promote pseudoscience and superstition. This deadly combination affects the reasoning ability of people.

Making people separate the life lessons from the pseudoscience is a challenge to promote the scientific temper.

4. Using nationalism to get support for pseudoscience by portraying pseudoscience and superstition as Indian ancient wisdom deliberately discredited by the West: There is a new trend of framing the pseudoscience in the west vs east binary by the pseudo-science propagators. To begin with, they claim that their claim is scientific, then they say that it was already known to ancient Indians which was only recently discovered by the West. Finally, they argue that the West says the same thing as ancient Indian wisdom does but terms ancient Indian wisdom as superstition while calling the western discovery as the science.

This line of argument plays with the general sentiment of Indians of a feeling of being neglected and suppressed by the west. Psychologically, believing such pseudo-scientific claims immediately becomes an act of rebellion, reclaiming India from the clutches of the West. Thus, it also taps into the basal nationalist feelings, which is on rising in recent years. Even the well-educated fall into this trap when pseudoscience is given a nationalist tinge.

Of course, the problems with this are obvious. Their claim is not scientific, to begin with. It's just a clever arrangement of scientific vocabulary. Besides, it suffers a common logical error of - two things sound the same hence they should be the same. For instance, quantum physics sounds weird and consciousness sounds weird and hence consciousness and quantum physics must be one and the same. Similarly, the metaphysical claim and scientific claim sound similar and hence they must be the same.

5. Laws that do not promote free speech especially criticism against religion: Promoting scientific temper clashes with religion (at least what is perceived to be part of religion) at some point. Given the trend of associating every superstition with religion, any criticism of superstition is a criticism of religion. It thus falls under the purview of "hurting religious sentiments" giving scope for zealous administrators and governments to harass the messengers of scientific temper.

6. Reducing scientific fact to an opinion: In the famous TV series F.R.I.E.N.D.S, a character named Phoebe argues regarding evolution: Evolution is your opinion, why can't I have my opinion, that's different from evolution, an opinion of creation.

The sinister thing about such arguments is that it reduces a scientific fact, which has evidence and there's no question of disagreement, to an opinion where it is reasonable to have an "opinion" contradictory to the evidence.

Once you reduce something to an opinion, the debate then becomes your opinion vs. my opinion. It then follows that we must agree to disagree while respecting other's opinion. Thus, the argument ends in a deadlock/stalemate. Phrasing pseudoscience in such manner makes it resistant to any further probing.

This tactic was earlier used limitedly in the case of the question of the existence of God, but it has grown enormously during recent times. Even the flat-earthers and sun sign horoscope believers are using this tactic. Apparently, one must respect the "opinion" of flat-earthers and sun sign horoscope believers.

For one, it is not a subjective thing where one can have an opinion. It is a scientific fact that the earth is flat and sun sign horoscope is absolute nonsense. And, one need not respect these opinions. One should just recognize the freedom to hold such opinions but others are under no obligation to respect these "opinions". They deserve all the ridicule they get.

7. Government support to pseudoscience: The phrasing of pseudoscience and superstitions as matters of religion, a cultural identity that is a matter of national pride makes it ripe ground for politicians to gain support by rallying people along these lines. The free speech-restricting laws become readily available tools for the government to suppress those who criticize the pseudoscience and superstitions. It makes the job of reformists extra difficult.

8. Parents do not perceive science education as a human development process: There is an interesting paradox in case of Indian parents obsessed with engineering and medical education on which they spend an enormous amount of money: Parents want their children to learn science but not use it to question the superstitions and religion. They perceive science only as an instrument of social mobility, not as a human development process. They are happy to hear their children solve the problems on gravitation but not when the child uses the knowledge of gravitation to debunk the pseudoscience of the moon affecting fluid levels in the brain.

If a teacher in school inculcates the questioning skills in children, parents are immediately worried about the attack on their beliefs and superstition. Often, it turns into complaints on the science teacher or at least requests to the teacher to not promote such thinking in the children. Some even go to the extent of changing the school or tuition teacher.

School is the place meant for the inculcation of scientific temper. Lack of parental cooperation at this stage is a significant challenge.

While the seven challenges above were about the nature of the content of superstitions, pseudoscience, and their justifications, the next two challenges are regarding the community of people who are supposed to promote scientific temper.

9. Science communication is pursued more like the spread of knowledge of science and not as developing critical thinking: The science columns of all the major newspapers and websites, and even the digital media initiatives, including the ones by various research institutes are about spread of knowledge of science. You rarely find content that criticizes superstitions, pseudoscience OR for that matter tries to educate people about the scientific method and develop critical thinking.

10. Lack of initiative from scientists and science communicators to take the pseudoscience propagators head-on: One of the reasons for treating science communication as the spread of knowledge but not the spread of scientific method is due to the lack of initiative from the scientists and science communicators to take the pseudoscience and superstition propagators head-on.
It could be due to many reasons. As late Prof. Majul Bhargava said, many scientists in India are themselves are believers of such pseudoscience and superstitions. Part of the reason is because of the phrasing of pseudoscience and superstitions as matters of religion and cultural identity. It's easy for those who grew up in this ecosystem to subscribe to these beliefs.

Some people of this community believe that holding such pseudoscience beliefs like astrology does not cause much harm. The other reason could be that either they are busy or they are not well versed with the new age media. The fact that the government supports such pseudoscience coupled with free restriction laws in India, and the violence against the reformers could also be one of the reasons.

In any case, scientists and science communicators should take these issues and pseudoscience propagating people head-on. If not, it will come to bite them back one day. It is difficult to get support for scientific endeavours from a society that does not value science. It is in their best interests to take initiative and take part in the social reform process too.


It is not to say that these challenges are insurmountable. Messengers of scientific temper are ready to face them on their own without help from the government except for one thing - the laws, and law and order. If the laws are amended to promote free speech, and law & order is improved to give protection to free speech, it boosts the activity of promoting scientific temper.