Why I Changed My Mind about the Quantum Multiverse

Recommended Pre-Reading:
Quantum Entanglement
Multiverses (Quantum Many Worlds section)

A truth seeker must always be open to new evidence. The new evidence must be added to the old, and all of it re-evaluated together. Sometimes the evidence in its greater context points in a direction other than what you thought was true, and when this happens, the wise person adjusts their beliefs accordingly. As a case in point, we’ll look at something I have had a strong opinion about on this blog, the quantum multiverse.

By Paul Anglada on Flickr

If you’ve read a lot of my science posts, you know I’ve been pretty hard on the quantum multiverse, also called the Many Worlds Hypothesis. In the multiverses discussion, I said I thought it was the least likely to be true out of the hypothetical multiverse types that come from physical theories. Since then, however, I have learned more about the arguments for its existence, most importantly the story of how the hypothesis came to be, and now I think it is reasonable to believe it exists.

Before we go any further, though, let’s remind ourselves what we are talking about. When quantum physics is mentioned, the layperson might think of the science of consciousness, or of parallel realities where events that were important to individual people or to human history played out differently. These are not quantum physics, they are purely science fiction, playing to our human bias that the universe revolves around us, and where “quantum” is used as a sneaky replacement for “magic.” Quantum physics, the real science, is the study of matter and energy at the scale of molecules and atoms and smaller.

When enough quantum particles interact together (millions, billions, trillions, and more), we get the classical physics that we know in our everyday life. We says that classical physics emerges from quantum physics. But classical physics is not the only thing that can emerge from quantum physics. Any property of quantum physics, when scaled up, can affect the macroscopic realm. Because of this, scientists and inventors have come up with technologies that use the unusual properties of quantum physics in technology, the most well-known example being the laser. Our experience of reality comes from the deeper reality of quantum physics, not the other way around. If quantum physics has implications that are counter-intuitive, we have every reason to take those implications seriously.

We’re going to talk about interpretations of quantum physics, so first things first, what exactly needs to be interpreted? It comes down to why we say quantum physics is weird: a quantum-sized particle can be in two states at once. What does that mean? Well, for example, an electron can be 50% spin up and 50% spin down at the same time. This is called superposition of states. It is like saying a basketball is spinning both clockwise and counterclockwise at the same time. It seems like a contradiction, and for macroscopic objects like basketballs it is, but for subatomic particles, it is normal. If you measure the electron’s spin, you will find it to be 100% either spin up or spin down, and then it will behave differently. But it was not 100% up or down before the measurement; the very act of measurement has changed the particle’s properties. This is called “collapsing the wave function,” and it is what needs interpreting.

For the Copenhagen Interpretation, that is the end of the story. The universe has probability baked into it, and measurements roll the dice. But the Copenhagen Interpretation has a problem: what counts as a measurement? If you try to measure the property of a particle by using another particle, the wave function does not collapse. Instead, the particles become entangled, that is, they are both in a combined superposition of states. For example, if you try to measure an electron’s spin using another electron, then both electrons will end up 50% spin up and 50% spin down. But here is where things get interesting. By using more traditional measuring devices, when we measure the electrons’ spins, we will find that one of them is spin up and the other one is spin down. We can’t know which is which beforehand, because there isn’t an answer beforehand. The only thing that is set in reality before the measurement is the fact that their spins will turn out to be opposite.

But what makes a traditional measuring device different from a particle? All measuring devices are made out of particles themselves, after all. So shouldn’t the machine we use become entangled with the electron as well? The machine only shows us one answer, not a superposition of answers, so that seems not to be the case. Why not? This is the famous measurement problem.

One proposed resolution for the measurement problem is that the collapse of the wave function happens when the experiment is observed by a conscious being. That is, the instrument used to take the measurement registers both spin up and spin down until someone looks at it, whereafter the entangled wave function of the particle and the device measuring it collapses, showing just one result. In other words, perception defines reality. However, this requires substance dualism, the idea that consciousness is fundamentally different from the rest of reality, that mind and matter are completely different things. People have had a dualistic view of mind and matter for all of recorded history. It is intuitive; our DNA comes pre-loaded with a disposition toward believing it. It just feels true. But feeling true has no bearing on whether something actually is true, and the lack of scientific evidence in support of dualism suggests that there is some kind of equivalence between consciousness and matter, which would mean the conscious observation interpretation of quantum physics is impossible.

One day in the late ‘50s, physicist Hugh Everett came onto the scene with a radical suggestion: what if the wave function does not collapse at all? What if any interaction between particles makes them entangled? This would mean that two interacting electrons become entangled; when they are measured, the instrument that measures them becomes entangled; when the scientist interacts with the instrument, the scientist becomes entangled; and when the scientist interacts with the rest of the world, the rest of the world becomes entangled. This would mean that after the measurement, the entire world exists in a superposition state, which is 50% reality where the electron is spin up, and 50% reality where the electron is spin down. Put simply, it can be thought of as if there is one universe where the scientists observe the electron to be spin up, and another universe where they observe the electron to be spin down. This is the essence of the Many Worlds Interpretation.

This sounds weird, and it’s only going to get weirder. As they say, extraordinary claims require extraordinary evidence. So what made me change my mind? What makes the Many Worlds Interpretation more reasonable than any other? It all comes down to consistency. When particles only interact with one another, they get entangled. This is a well-documented scientific phenomenon. The larger the number of entangled particles, the harder it is to control all of them, so the easier it is for something external to the experiment to “mess up” the entanglement. But what would it mean to “mess up” an experiment? It’s just more particles interacting with the entangled system. And we know that when particles interact with other particles, they get entangled. So we could think of it as the external world coming in and messing up the experiment, but if we want to be consistent, we should say the entanglement is escaping to the rest of the world, including the brain of the person doing the experiment.

This is extremely counter-intuitive. I certainly feel like I am in one specific state, not a superposition. But what would being in a superposition feel like in the first place? We might imagine two images playing over our eyes, like a transparent movie playing over another movie. But that would only happen if the information from both states came together in the same brain. Remember, our brain is also in a superposition, not working as a single machine in both states. So a person in quantum superposition would feel completely normal, as if they and the objects they see and interact with are in state A, and not state B. And they would also feel as if they and the objects they interact with are in state B, and not in state A. Both are true, and they would notice nothing weird at all, because the states of their brain are completely cut off from each other. In effect, the universe has split in two, and that is where the “multiverse” idea comes in. More generally, as I argued in the multiverses discussion, it is not the splitting of distinct universes, but an infinite-dimensional smear of universe-ness.

By Maria Morri on Flickr

And now, when I look back at my former self, I see a hypocrite. In the multiverses discussion, I said people are drawn to the Many Worlds Hypothesis because the idea that reality is simply probabilistic at the quantum scale is too weird. But I got it backward. The reason that people like my former self cling to the Copenhagen Interpretation is because the Many Worlds Hypothesis is too weird. But weird as it is, it is the only interpretation that solves all the puzzles of quantum physics and leaves no loose ends behind. It is the natural logical conclusion of entanglement, and it makes the measurement problem go away. Out of all the interpretations of quantum physics, those we discussed and those we did not, I now think Many Worlds is the most likely to be true.

But it’s just an interpretation, isn’t it? If it can’t be tested, then what is the point of debating it? Well first of all, here on A Scientist’s Fiction, we search for truth in whatever way we can, and if that means using pure logic, that is what we use. However, in this case, we don’t have to. We can test the quantum multiverse. After all, it’s not just parallel realities. That’s TV sci-fi. The quantum multiverse is an extension of regular old quantum entanglement, which we see in the lab all the time. It makes a prediction: if we have the right kind of experiment, we should be able to put a human being in quantum superposition. Researchers keep finding quantum properties in larger and larger systems, so it should be theoretically possible.

I don’t know how the exact details of such an experiment would play out, but it might go something like this. Imagine we send a human test subject into a room that is 100% soundproof, vibration-proof, and heat-proof. After we close the door, the subject sees either a red light or a blue light, triggered by the measurement of an electron’s spin within the room. To all outside observers, the subject would be in a superposition state of red + blue. Suppose this person was instructed to lightly touch one of two sensors, which connected to a second electron, telling it to either be spin up or spin down. The experimenters outside the room would then do tests on the two electrons, to see if they are in a superposition of states. If they are, then the human test subject is also in a superposition of states. Then they open the doors, the test subject walks out, and tells the researchers what color of light he or she saw. They then measure the particles, and indeed their spin is oriented in accordance with the prediction. This would mean that the test subject was entangled with the electrons, in a superposition of states, and now there are two universes, one where the subject saw red, and one where the subject saw blue. The quantum multiverse hypothesis would be supported by evidence from a prediction of its own.

Schrödinger's Cat

Changing my mind due to more complete evidence is something I am well-practiced at, so when it came time for the quantum multiverse, it was no big deal for me. However, for those less practiced, it can be frightening. Maybe after reading this you are not convinced that the quantum multiverse exists, and that’s fine. Skepticism is healthy, especially for topics as complicated as quantum physics. But it is also healthy to direct your skepticism toward the beliefs you already hold, and I encourage you as a fellow truth seeker to reexamine your beliefs every now and then. Whether you find them to be valid or in need of replacement, I can guarantee the practice will make you wiser and bring you closer to the truth.

Negative Morality: The Divine Hierarchy

Morality:
Intuitionism
Authoritarianism
Divine Command and Attributes
Ethical Egoism
Utilitarianism
Virtue and the Golden Rule

Negative Morality:
Divine Hierarchy

A year ago, we did a series on morality, where we looked at the philosophy of morality, and the moral systems that are discussed in intellectual conversations. Since then, it occurred to me while thinking about the viewpoints of villains and bad people, as well as some misguided people with good hearts, that there are other moral views we have not talked about. These moral systems are not widely considered by philosophers, because they cause oppression and suffering, rather than reduce it. So I have decided to do a mini-series called Negative Morality, where we take a look at these moral systems, so that we may avoid their pitfalls in our own views.

If I were to start the moral series over, I would put Ethical Egoism and Authoritarianism in the negative morality category. But the original series has a structure to it, and I don’t want to mess that up by reclassifying them.

Our topic for today is what I call the divine hierarchy. The concept is simple: the degree to which you are good or evil, holy or unholy, worthy or unworthy, is not primarily determined by what you do, but by what you are. It usually goes something like this: above all are the gods (or just God), beneath them are holy beings like angels, below them are mortal men, below mortals are the animals, and below the animals are demons and unholy monsters. Within each category, humans especially, the beings may be divided into sub-classes, which may either be stratified into discrete levels or smeared out over a continuous spectrum.

This leads to the divine hierarchy’s biggest and most obvious flaw: it makes it very easy to justify prejudice of all kinds. In the hierarchy, men are usually placed above women, the upper classes above the lower classes, and the people of the nations whose armies conquer above the peoples who are conquered. For example, the West has a historical dark side of seeing the world as full of morally inferior savages, theirs for the conquering. History is much more complicated than that, of course, with many positives and negatives, and it can be argued that the attitude of colonialism has greatly diminished from the modern world, but that is a discussion for another time. The point is that a morality structured around a divine hierarchy makes it easy to justify racism, sexism, and discrimination by all other kinds of immutable characteristics. “Know your place” is a common phrase to hear from someone higher in the hierarchy to someone lower down who tries to exercise more freedom than is considered appropriate for them.

In some versions of divine moral hierarchy, it is possible to move up or down the spectrum by performing good or bad actions. More often than not, it’s easy to move down, but very hard to move back up. There is a set of actions, usually based on notions of cleanliness and obedience, that are identified as “bad,” not because the consequences hurt people, but because the action covers you with an invisible sludge called “sin” and makes you less holy. Once covered in sin, there is one of two ways to have it removed, depending on which hierarchy model one believes in. The first is to do penance, an action prescribed by the religious leaders as a medicine for the soul, which may or may not result in good actually being done. The second is to pray that God (or whichever of the gods views you favorably) will be merciful and “wash your sin away” instead of bringing upon you the punishment which your unholy existence deserves.

It should be noted that divine moral hierarchy is not the only context in which sin and religion can be viewed. Some perspectives are not so harsh. There are also other ways that people justify prejudice. We have talked about some of them in other contexts elsewhere on this blog, and may do so more in the future.

If used in a fantasy story, a divine moral hierarchy doesn’t have to be bad. Middle Earth, the setting for The Lord of the Rings, exists in a Divine Hierarchy, with Illuvatar the creator on top; then the Valar, which included Sauron’s master; then the Maiar, which include Sauron and the wizards; and then the elves, dwarves, hobbits, and men. It is also present in the lesser known Space Trilogy by C.S. Lewis, with Maleldil (basically Jesus) on top, the Eldila (angel-like sci-fi beings) below him, the hnau (sentient creatures) below them, and non-sentient animals implicitly below them. In fiction, we can look at the downsides of a divine hierarchy, or anything really, and say “in this world, the bad consequences just don’t happen.”

If a moral system leads to more suffering than would exist without it, then it is not moral. The idea that people have moral worth based on the genetic lottery of birth clearly does more harm than good, and we should train ourselves to avoid slipping into that way of thinking. If we see others who are consciously or unconsciously influenced by a negative morality, then we should kindly and respectfully ask questions that lead them toward recognizing it.

Beware the Scapegoat Mentality

In the world today, there are a lot of negative feelings going around. People feel uneasy and resentful, and they don’t know why. It is as if there is some unseen hand quietly out to get them from the shadows. So when someone stands up, points a finger, and says, “those people are the reason you feel this way,” they are met with praise and adoration, because now the people have a name and a face to blame for their unhappiness.

The person or people at whom the fingers point is called a scapegoat. Perhaps they or a person from their group have done something awful, but it is more likely that their public actions are looked over with a fine-toothed comb for one little speck of dirt that people can use to justify believing that they are a bad person. Scapegoating is a tragedy, because at best it takes the reputations of innocent people and drags them through the mud, and at worst it results in a witch hunt. It is the easy way out, a simple solution that requires no thought. It does not solve the problem, only gives people a sense of self-righteousness and retribution.

Don’t fall prey to those who would create a scapegoat. And don’t scapegoat those who scapegoat others; that’s still scapegoating.

Immigrants. Atheists. Christians, Muslims, and Jews. The President or other national leader, current or past. Liberals, progressives, and Democrats. Conservatives and Republicans. The media. Drugs. Guns. Capitalism. Socialism. Postmodernism. The Patriarchy. These are all used as scapegoats, and while you may be able to find fault with any of them, none of them are the real problem.

So what do real problems look like? Because they are real, they behave like reality, with a well-defined mechanism in which every part fits logically with every other. To find them, it takes a willingness to put in the work, and a commitment to truth, no matter what it turns out to be. Focusing on who is to blame doesn’t solve anything, so let’s put our anger and discomfort aside, and look for the real problem and real ways to solve it.