Quantum Immortality book

The Quantum Immortality section of my book How To Live Forever takes up a lot of space, partly because of the work involved in describing the many different ways that the universe can be infinite in size and shape.

I’m considering cutting it right down to just one or two pages, because I don’t want an unproven (but compelling) idea taking up a lot of space in an otherwise proof-based book.

But, I also don’t want to just throw the work away. So, I’m thinking of expanding it into a book of its own.

There’s certainly a lot of topics around quantum immortality that could do with investigation.

Example topics:

  • What is quantum immortality?
  • How do we know it is real?
  • How can you make money through quantum immortality?
  • What about old age?
  • If you are immortal, how should you behave?
  • Is there any evidence that Quantum Immortality is true?

I’ll explore a few of these here very briefly.

What is quantum immortality?

Quantum physics suggests that there may be infinite worlds, one for every possible solution in a quantum equation. This means that for every chance that you might have died, there is also a chance that you didn’t. You can only be aware of universes where you survived, therefore your awareness is (and therefore, you are) immortal.

How do we know quantum immortality is real?

We don’t. The many worlds interpretation (MWI) of quantum physics is just one of a few plausible interpretations. The one most commonly known is the Copenhagen interpretation (CI) which suggests that when a quantum event happens, the event magically “collapses” to choose one possible result as reality. Occam’s Razor suggests that the simplest answer is usually the most correct. CI requires the universe to somehow choose a reality. MWI does not. MWI is simpler and therefore probably correct.

How can you make money through quantum immortality?

One possibility comes to mind: create a suicide device (do not do this: this is a thought experiment) which will release an overdose of a poisonous gas during your sleep if certain numbers don’t come up in the lottery on a specific night. Buy those exact numbers on a lottery ticket for that night. Go to sleep. If you wake up the next morning, then you are now rich. Quantum Immortality suggests that there are billions of worlds where you will not wake up, but you won’t experience those.

What about old age?

The traditional thought experiment for Quantim Immortality is drastic – you are shot with a gun that is triggered based on essentially the flip of a quantum coin. When you get to an extreme age, every breath could be your last. This is random, which is exactly what Quantum Immortality takes advantage of. So in some universes, your current breath may be your last. In others, you will go on to breath at least one more time. And repeat, forever.

If you are immortal, how should you behave?

Don’t be an ass. Just because you are immortal does not mean you can treat other people as “lesser mortals”. Remember that even if they can’t kill you, you could still spend a lot of time in prison or in hospital. Quantum immortality ensures that you will survive everything that is thrown at you, but it does not ensure that it won’t hurt.

Is there any evidence that quantum immortality is true?

No. There is a lot of circumstantial evidence, but nothing hard. For example, the universe can be infinite in many ways (size, multiverse, mathematical reality, etc), quantum physics is completely consistent with the many worlds interpretation, we are currently living at a time when all diseases (and even old age) are being cured and people are getting older and older around the world. All of these increase the likelihood that you can survive anything, or at least survive long enough that the disease that might eventually kill you will be cured before it gets you.

This is all off the top of my head, written while riding a bus to work. I think I could come up with a further few questions to thrash out into full chapters

If a quantum immortality book sounds interesting and you have any questions you’d like me to explore, please comment below.

Is true immortality possible

Is immortality real? Is the concept of it even realistic? What about quantum immortality – doesn’t that make it real? Is quantum immortality real?

“Immortality” is a tricky word, because it leads to some awkward questions. Let’s imagine it means that “you will live forever”, well then we need to define what “you” means.

“You” are the sum of your histories. Let’s say you get hit in the head and you lose most of your memories, and change from the happy person you are into a grouchy paranoid violent mess. That is still “you”, based on the sum of your histories, but if you were to compare the two people, you would not call them the same.

Unfortunately, quantum immortality does not guarantee that it is the current “you” that will live forever. In fact, it’s also very possible that your current you is simply not suited to live forever anyway.


Anne Rice’s books “Interview With The Vampire” and “The Vampire Lestat” are about two vampires who have different ways of dealing with living forever.

Louis is an 18th century man who does not grow with the times. His way to deal with advancements such as cars, radio, computers, is to retreat away from society into a house where he can surround himself with what he is familiar with.

Lestat, though, moves with the times. He accepts that he cannot change the world, so should change himself instead.

Even within the span of a normal human’s lifetime, you can see Louis’ mindset affecting people. The joke is that only young people can deal with new technologies because they are born into them. Of course, those young people are eventually surrounded by technologies that they were not born into, and the cycle continues.

In order to live even two centuries, you must keep up with modern technologies and society. This changes you. The “you” in a century may be a completely unrecognisable person from the “you” today.

This means that “you” cannot live forever.

However, this is not a bad thing – “you” are not even the “you” that existed just a minute ago. Your thoughts evolve, your memories fade, your personality adapts to changing needs.

The only way to stay exactly the same person is to freeze yourself in time. And if you do that, then you are not living.

For quantum immortality, old age is just a step towards renewal. You will discover something in new technology that fascinates you and gives you a “rebirth”.

This will change who “you” are, but it will be a good change, because the old you was about to die a boring old death stuck in the past.

longevity vs immortality

The difference between longevity and immortality is that “immortal” implies that a person cannot die, while “longevity” implies that a person has a good chance of living a long time.

A person with centuries-long longevity can still die by accident or by an undiscovered disease, etc.

Immortals, though – An immortal being can regenerate from nothing, if need be, or is impossible to kill because every attempt to kill the person fails at some point.

The only way a human can become immortal is if quantum immortality is true. The normal methods of increasing longevity merely make lives longer, but immortality is different – a person with longevity still has a finite life-span. An immortal, though, has infinite lifespan.

With quantum immortality, a person literally cannot die, even if they want to. With quantum immortality, old age is just a temporary thing, for example – a person might live for tens of years as an old person, and suddenly a breakthrough announces a cure for aging (there are many senolytics currently under human trial, by the way – drugs designed to counter aging).

The idea is that in an infinite multiverse, immortality is certain – there is always a universe where you survive, no matter how unlikely. So your life will continue onwards forever.

Is quantum immortality real? There is no way to be sure either way. But it’s one way of explaining a load of coincidences – for example, why are we alive at this exact time when there are so many amazing cures happening?

Read “how to live forever” – book available in paperback and Kindle

is the universe a mathematical structure?

Quantum physics can predict the behaviour of particles and energy to an extraordinary degree. Quantum Electrodynamics, for example, predicts a value for the electromagnetic fine structure constant which is so accurate that we have not been able to find a difference between the predicted value and the real value despite measuring to 14 decimal points (the measurements are difficult!)

The point of this is that the result of the most precise measurements we have ever made can be predicted using some math, without needing to do the actual measurement.

This is because the universe is mathematical in nature. There is nothing in the universe which we don’t have a formula for.

A co-worker retorted “what about the soul?” Treating that like the serious question she intended it to be, even thoughts and so-called “free will” can be predicted using math. Thoughts are determined by processes in the brain involving chemistry and electricity; both of which are well understood and predictable.

We have artificial neural networks which work similar to the brain. While they sometimes do things that we don’t immediately understand and which look like thought, we can examine the weights and synapses of the network and break every thought and decision right down to the 1s and 0s that they’re made of.

Just because we don’t understand how something works, doesn’t mean that it’s magic. The brain is not magic. Each tiny part of the brain works in very precise and predictable ways, and the thoughts and decisions that we call “free will” emerge from the billions of neural firings that happen every second (13 billion per second! There are 86,000,000,000 neurons in the brain, and they all fire on average about .15 times per second).

Everything that happens in the universe is predictable by math.

Even the universe itself, devoid of all matter and energy, is still a mathematical structure. Why are there exactly three space dimensions? An answer can be found in a theory called “Causal Dynamic Triangulation“, which describes how exactly three dimensions of space can arise from a set of mathematical rules involving triangles. The theory is more accepted than the alternative highly-regarded “loop quantum gravity” theory, because it produces exact measurements between points (impossible in LQG), and because it describes space both for Planck-scale measurements (the smallest possible), and for astronomical scales as well.

The fact that everything in the universe is predictable with math, even space itself, allows the possibility that you can create a single equation that predicts absolutely everything that can happen.

And if you run that calculation? You would be able to pick a precise date and time, and tell exactly what the state of the universe is on that time (or at least, you would know the most likely layout – quantum mechanics is very precise but also fuzzy).

This is regardless of so-called “free will”. Everything is predictable, including thoughts, if you have enough starting information.

It gets weird now: if everything, including thoughts, can be predicted using a single (probably very complex) formula or algorithm, then how do you know that you are real?

I mean, if everything you do is simply a result of an algorithm following its steps one by one, as physics shows us, then are you anything more than just a bunch of variables in that algorithm?

And if so, then is there a difference between the algorithm running for real in some super-computer somewhere, as people like Elon Musk suggest, or running in potential simply because every mathematical algorithm that can exist must have results whether the algorithm is run or not?

Personally, I’m in the latter camp for a number of reasons:
1. If the universe is running in a super-computer somewhere, is the super computer real or running inside a simulation of its own?
2. The eternal question “why is there something rather than nothing” is solved forever if there really is nothing and everything we see is simply a shared simulation running in potential but not in “reality”.
3. It also helps explain another related issue – is there exactly one universe? No, there are infinite universes, for each possible result of this universal algorithm, and every single one of them “exists” is a result, even if they are not “real”.
4. What is reality? When he heard the idea that nothing is “real” and that reality is subjective (immaterialism), Samuel Johnson famously kicked a rock hard and shouted “I refute it thus!”. However, that’s not a refutation – in a universe where you and I share a hallucination, everything in that hallucination is real to us, whether the objects are objectively real or not.

A very welcome bonus to the idea that the universe is mathematical in nature, is the possibility that it leads to personal immortality, through the idea of quantum immortality.

quantum immortality and old age

The idea behind quantum immortality is that there are infinite universes, and everything that can happen, happens in at least one of those universes. Thus, if you were to fall from a building, for example, then you would, in at least on of those universes, land in a bush or tree, or get blown onto a canopy, etc.

The scenarios described in quantum immortality usually only cover drastic events, though, where the “decision” between live and die is obvious. A gun fires, a bomb explodes, you fall from a building, etc.

But old age is not quite as obvious as that. It’s a lot more gradual.

Having said, that, though, maybe old age is the same?

When we say that someone died of old age, what comes to mind is that someone gradually declined until either they just stopped breathing, or their heart stopped.

Those are definitive moments that, if we’re talking about old age degeneration, and not something traumatic, has no obvious cause and is random in nature. Will the heart stop now, or in a minute? Will this be the last breath? It’s impossible to predict, making this ideal for quantum immortality.

You see, with quantum immortality, the fact that something is random means that it will happen in some universes, and won’t happen in others.

So, in many universes, the person that’s lying on the bed dies this hour. In some others, in a few hours, and in even rarer universes, the person lasts the day and is still hanging on tomorrow.

Quantum immortality relies on there being a universe for every possibility. Not just most. Every. So, if there is a random chance that the person will survive the day, even if the chance is one in billions, then it will definitely happen.

And because every death has some cause behind it, even if we don’t yet know what the cause is, the person that is dying on the bed just has to last long enough for the cause to be found and its cure applied.

Quantum immortality guarantees that the person will survive long enough, even if it’s tens (or hundreds!) of years. Luckily, though, we are living in very interesting times, and all causes of death are being discovered and cured, with new cures available almost every week.

With quantum immortality, old age is not to be feared – it just means you’ll be sick for a while until the cure for aging (*cough*senolytics*cough*) is found.

If you want to read more, read the chapters on Quantum Immortality in my “how to live forever” book.

Is Quantum Immortality Real?

This is a difficult one to answer. It’s kind of like asking “is God real?” – there is no compelling evidence either way.


Quantum Immortality (QI) is the idea that if the Many Worlds Interpretation (MWI) of Quantum Mechanics is true, then every possible universe exists and is just as real as this one, including every universe where you survive cancer, you fall from a building and land in a passing truck carrying hay, your plane doesn’t crash, cures for aging are discovered before you get old (hmm- sounds like this one, right?).

Because the MWI is just an interpretation of the math of Quantum Mechanics, and gives exactly the same results as all other interpretations (such as the popular Copenhagen Interpretation), there is no way to prove that it is correct or incorrect.

It boils down to faith, in the end – which one are you more comfortable believing?
1. that a quantum mechanical wave calculation is performed every instant of time, and a random result is magically chosen to become reality; the whole thing to be repeated ad infinitum (Copenhagen Interpretation)
2. that the quantum mechanical wave equation represents all versions of reality that exist, and that we are merely one of the results.

In one of these, a magical step is taken which has never been explained, and our universe pops out as the only result. In the other, the wave equation is simply a description of all realities and our universe is no more special than any other.

In a way, the puzzle is like the old physics/philosophy question – “Why is there something rather than nothing?”

Given that “in the beginning there was nothing” (let’s agree), it does not make sense that suddenly there is one single universe, and that is all that there can be. Exactly 1. No more. No less.

Even having 1 as the number of possible universes is not sensible. How did we get from 0 to 1?

Physics shows that it is certainly possible for a universe to appear from nothing. In fact, the Heisenberg Uncertainty Principle demands that a universe exist, because an empty universe is one in which the velocities and positions of all particles (all zero of them) are known, and that is forbidden.

But there is nothing in physics that says “there can be only one reality”. The math always takes place against hypothetical states of the universe, and there really is no difference between a fully calculated hypothetical simulation of a real universe (this one, for example), and the actual “real” thing. Especially from the point of view of a person living within that universe.

My own opinion is this: Quantum Mechanics describes the universe exactly. There are no known differences between QM and “reality”, that I am aware. So the only question is which interpretation is correct. Well, I believe that the simpler of any two explanations is usually the correct one. Because MWI does not require any magical “quantum collapse” step in its equations, I believe it is simpler and therefore probably correct.

The next part of this is to decide whether that means that the immortality part is real. That part is philosophical in nature.

Are you the exact same person that you were yesterday? Did you even exist yesterday?

The only evidence that you existed yesterday is what your memory and your senses tell you. But, your senses can be fooled, and your memory can be fooled as well. How do you know that your memories of yesterday were not planted in you while you slept?

If you were to die today, and an exact clone of you were to be created and given your memories, that clone would think it was you, and so would everyone else that knows you.

When you save your state in a computer game, make a mistake, then reload that state to carry on, to the characters in the game, it’s as if the mistake never happened in the first place.

If you die in this universe, and survive in another, it’s as if you never died in the first place.

In fact, coming back to the beginning of the article, for all you know, in another universe only a few minutes ago, you died of a heart attack. But do you remember that here? Of course not.

The only memories you can possibly have are those of a person that has survived everything thrown at them. The thoughts of a dead you might as well not exist at all.

While there is no way to “prove” that quantum immortality is real, I think it’s much more comforting to assume it is, than to presume it is not.

You gain nothing by disbelieving, other than a sense of finality and doom. At least by believing, you can be a bit happier in your day and nicer to your fellow humans, because you’re going to be around them for a very long time.

Mathematical Universe

For the last few hundred years, we have been able to gradually pin down exactly how everything in the universe works, right down to a very small group of equations.

What that means is that everything in the universe can be predicted using math (either exactly, or statistically).

Philosophically, there is no difference at all between a mathematical description of you observing the universe, and the real you observing the universe. How could you tell which is “real”, when everything that happens in “reality” can be predicted by just doing the math? Is there a difference between a mathematical universe and a “real” universe?

In a way, this means that we are all like NPCs (non-player characters) in a computer game, all of us convinced that we are real and that the world we inhabit is real, when in fact, the entire game and ourselves are being simulated in a universe-encompassing machine.

In reality’s case, what is this universe-encompassing machine? Well, math can be worked out on a computer, on paper, or in your head, and if done correctly, it will always come up with the same answers. Math is objective – it doesn’t rely on a medium. It doesn’t need the paper in order to be correct – it just is.

Consider the sequence (1, 2, 3, 4, …) for example – the next number is 5, no matter whether we compute it or not.

Even incredibly complex equations obey the same objective law – if you consider an equation that predicts the position of every particle in the universe in one second – this equation will have an answer whether it is calculated or not.

All equations exist in potential. This means that the equation “x+y-z” has just as much reality as the sequence “1, 2, 3, 4, …”, and therefore the answers to those equations also all exist in potential.

This means that every possible universe exists as a mathematical potential, and because there is no discernible difference between “reality” and a simulated universe (for people inside those universes), it means that every single universe, that you can describe mathematically, exists.

And by extension, every universe in which you survive the present and the near and far futures, also exists.

black holes and baby universes

Yesterday, I was talking to some of my students at the Coolest Projects seminar in Dublin, and we ended up discussing Nikodem Poplawski’s idea that all black holes contain universes, and how that leads to there being infinite universes, and therefore we are all immortal (due to quantum immortality).

In Newton’s classical mechanics, the more mass there is in a volume, the stronger the gravity is near that volume.

However, if each black hole contains a universe, and then recursively contains its own black holes and therefore further universes and black holes (turtles all the way down!), then that means that each black hole can potentially contain infinite mass, and so Newton’s math suggests that the gravity of black holes is infinite in strength.

But it’s not. We know this because if it was, there would be nothing outside black holes – it would all be sucked in.

So how can a black hole contain potentially infinite mass, and yet not exude infinite gravitational attraction?

The solution lies in the speed of gravity.

If the sun was to suddenly vanish from our solar system, then the Earth would continue to orbit the space where it was for 8 minutes, because gravity waves take time to propagate across space.

If a black hole creates its own space inside itself, due to the huge pressure and friction, then gravity from the absolute center (for example), takes longer to get to the outside because it has more space to traverse.

We know from our own observations that this universe is expanding. If all universes within black holes are created by the expansion of space, then it is possible that the space is created at such a speed that gravity cannot travel from one side of the hole through the center to the other side, because the space expands so fast that it simply never gets there.

We know as well that in our own universe, there is no such thing as empty space. Virtual particles appear and disappear all the time. It makes sense that sometimes these virtual particles will appear, separate, and sometimes not recombine and vanish. Sometimes, matter (and therefore mass) will appear out of nothing.

And so, the inside of a black hole will create its own space, alone with its own new matter, seeding a new universe.

So how does this all tie in with immortality?

The number of possible configurations of energy/mass in a universe depends on the size of that universe. Space is made of nodes and lines connecting the nodes. There is no “distance” between the nodes. “Distance” and “size” are measured by literally counting the nodes and lines.

Because space is quantised, anything that is in space must be located on a specific node. This means that if there are three nodes, for example, then a point particle can only exist in one of three places. This in turn means that if you have four universes, each composed of three nodes (in the same configuration for simplicity) and one point particle, then at least two of those universes must be exactly the same.

The same principle means that if you have larger universes and more particles, there is still a limit to how many universes you can have before two of them must be exactly the same.

For example, if there are 4 nodes (again, configured similarly for simplicity) and 2 point particles, there are only 16 unique configurations (4+4*3). If there are 3 point particles, there are 40 unique configurations (4+4*3+4*3*2).

In the first case, if there are 17 universes, at least two are exactly the same. In the second, if there are 41 universes, at least two are exactly the same.

No matter how large the universe gets, there is still a number that equates to how many possible configurations it can be in. If more than that number of universes exist, then there are duplicates.

If all black holes contain universes, and there are then recursive universes and black holes, then there are infinite universes, and therefore there are infinite duplicates of universes.

This means that there are infinite universes which are exact copies of this universe, including copies of you, which have your exact history, memories, and thoughts.

If there is a chance that you will die tonight, there are some universes where you will die, but you will only be aware of those in which you survive.

And therefore, black holes and baby universes, lead to a kind of multiverse immortality.

the multiverse and immortality

I was reading a bit about Nikodem Poplawski’s theory of black holes and baby universes, and thought I might expand on how that can lead to a kind of multiverse immortality (or quantum immortality, even though this is not a quantum multiverse idea).

The general belief is that black holes are “infinitely” dense, which suggests that anything that goes too close to one is stretched (spaghettified), and then torn apart by tidal forces, leading to an eventual crush once inside the hole proper.

Nikodem’s idea is that it is impossible to make matter infinitely dense, as the torsion forces the matter to expand, even while gravity is forcing it to collapse. Eventually, the pressure becomes so high that the contained matter essentially explodes, even though from the outside, we would see no such thing.

The explosion manifests on the inside of the black hole as a Big Bang, from which is born a new universe. This may seem unintuitive, but I think what he’s suggesting is that the explosion forces the creation of space itself. Imagine a TARDIS’s interior exploding into being, inside a normal police box, for example. From the outside, we see nothing. On the inside, we see a whole universe born and growing.

How this leads towards immortality is that if every black hole can have a universe inside it, as Nikodem suggests, and each universe is can have black holes inside them, then there are a potential infinite number of universes.

If there are infinite universes, then every possible configuration of matter can be found somewhere, and will also be repeated somewhere. Since the universe we are in is definitely a “possible configuration of matter”, then that means that there are infinite copies of this universe contained throughout the universe, either directly inside its black holes, or inside black holes contained in the black holes (etc). In other words, the universe is infinite in this idea, but in a “nested” kind of way.

If there are infinite copies of this universe, then there will also be a universe for ever possible choice we make, or every random event. So, if you were to have a stroke tomorrow and die, there will also be infinite universes where you don’t, and since your identity is ultimately physical in nature, “you” will survive in those and will not even remember that “you” had a stroke.

quantum immortality as a get-rich-quick method

First off, do not do this – there is absolutely no proof that quantum immortality is true. Having said that, let’s look at an idea that could be a very quick way to win a lot of money if it is true.

Steps to winning a whole load of money easily, given the premise that quantum immortality is true:

  1. create a program that can read a lottery website and check its numbers
  2. create a device which can release a load of carbon monoxide into a room when triggered
  3. create another device which can detect when you are fully asleep
  4. buy a lottery ticket
  5. set up the program and two devices, so that on the night of the lottery, after the lottery has run and its numbers have been published to its website, the program will trigger the carbon monoxide to be released into the room after you are asleep, if the numbers checked do not match the numbers you bought.

Now, all you need to do is buy a lottery ticket, and on the night of the lottery, don’t check it for yourself, but just go to sleep.

You will wake up the next morning after winning the lottery the night before.

The alternative (that you did not win) results in you simply not waking up at all. Given that there are an infinite number of universes, and that “you” are the conscious emergent property of your memories and neural functions, and memories are properties of physical neuron layouts (of which there are infinite copies in the infinite universes), then “you” are the person that wakes up the next day, after winning the lottery the night before.

There are ethical problems with this. Let’s say the chance of winning the lottery was 1 in 1,000,000. For every universe in which you win the lottery, there are now 999,999 universes where you are dead. Of course you don’t experience those universes, but those people you left behind did.

Does that matter? They are, by definition, in completely different universes from the one you experience, so does it really matter?

I’ll leave that to “you” to decide.

And, of course, another reminder that if quantum immortality does not exist, then you have just killed yourself. Painlessly, let’s make it clear, and you were not aware of it happening, but you are nonetheless very dead. Keep that in mind, and don’t do the above.

[edit – May 15] – as pointed out on FaceBook, if QI is true, it is much more likely that you will screw this up and just damage your lungs very badly, than that you will successfully create a suicide machine on win the lottery.