So, what weirdness am I talking about? Wee-ah-ooo—quantum weirdness. For anybody who knows just a little bit about quantum physics they should feel there is some strangeness going on down there in the quantum world. This world is the realm of the atom and below (particles and sub-particles).
[Disclaimer: what I have to say in this blog is my own view of quantum physics, some of what others would agree with, and some of what others would not agree with. Or, I could be wrong, but so could they.]
I think the beginning of all this quantum weirdness is that there is no cause and effect in the quantum realm as there is in all other levels of existence above the atomic. We cannot tell when a quantum event is going to take place, where a particle may be, what a particle’s momentum (a combination of velocity and direction of movement) is, or how much energy a particle has. There are other forms of indeterminism in quantum mechanics as well, but I think you can see what is going on or not going on here.
What makes for the transition from the quantum level to higher levels of the universe (with the possible exception of black holes)? Physicists have yet to figure it out. My take is that it involves macro (above the quantum level) interactions. Once these interactions occur cause and effect is turned on so to speak. One such interaction that gets lots of attention is measurement, which makes for its own weirdness (more below).
Because of the lack of cause and effect in the quantum world the only way we (physicists really) can predict what is going on is in a statistical manner (called quantum mechanics). This is not the same statistical explanation such as what heat is. With heat all the particles are behaving in a normal manner, but we can only describe this behavior statistically. With quantum mechanics it is different. Here nothing is normal as far as cause and effect is concerned.
In our everyday world if you drop a ball it falls to the ground. We now know this is due to the force of gravity. If you let go of a atomic particle you do not know where, how, or why it does anything. Where, because any path it might travel is indeterminate; how, because in quantum mechanics it follows all possible paths; why, because there is no cause and effect.
I will add that the lack of causal relationships in the quantum world shows that the universe itself needs no cause for its existence. This is because when the universe began its expansion it began it from a size at or below the size of the quantum. Because of this there is no need for any type of god, deist or theist, for the universe to begin to exist.¹
I left out pantheism because with this type of god—god is the universe. If this type of god has an eternal existence, than the universe would have no beginning. There is one more possibility here. It is that a pantheist god created itself. How that would work I am not sure. Also, in regards to polytheism it could be utterly confusing who created who, or who created what.²
I mentioned above the phenomenon of measurement. Or, as I have heard it put, the measurement problem. I do not see that there is an actual problem here, though. I mean physicists have no problem making even very accurate measurements (possibly the most accurate) or calculating the statistical spread of possible results. The problem is a conceptual one or an interpretational one, not a pracitible one.
The issue at hand is that there is no way to know the exact value of any quantum state (e.g. position, momentum, energy) before a measurement is made. There is no exact prediction as with macro level measurement. Well, this maybe considered normal for any measurement, except for in the act of measurement experimenters actually affect the state of the quantum system in the experiment. You might ask how this is so or why this situation comes about? As for the how I will attempt to explain in a moment; as for the why that is the major problem as I see it.
The how can best be seen through what is called the two slit experiment. In this experiment there is a screen with two slits in it. On one side there is a particle gun, which shoots one, say an electron, at a time. On the other side is a detection screen which measures where the electron is when it arrives at the screen. Well, lets say you attempt to measure which slit the electron goes through. When this is done the pattern on the screen is a set of clustered marks. However, if there is no measurement of which slit the electron went through, the pattern on the screen is a diffraction pattern as if a wave went through both slits.
You might ask are these electrons particles or waves? The answer depends on if a measurement is made of which slit the electron went through. If a measurement is made to detected the electron going through one of the slits, then it acts as a particle; if no measurement is made, then the electron acts as a wave. So what is the problem here? Remember, only one electron is fired at a time. So, how can there be a wave pattern on the screen if no detection is made? A proposed solution to this conundrum is the electron goes through both slits behaving wavelike.
Now this situation is certainly weird, or would be if we were observing a macro size object, but this is the norm for a quantum size object. Why this weirdness at the atomic level? Again, physicists do not know, and some do not care. They just do their experiments and except the results. But, the physicist outside the lab, or a philosopher, or the person on the street wants to understand why? Remember, there is no apparent cause and effect in the quantum world. This is why we cannot understand why. Because when we ask why, we are asking for the cause. So, sorry you are out of luck if you seek an answer to why this weirdness is happening in these experiments.
So, what is the electron (any particle really) a particle or a wave? The often hard to accept answer is that it is both, and physicists are only able to definitively answer the question when a measurement is made. This whole situation is known as wave/particle duality. I will have more to say about this later on.
Another aspect of the measurement problem is found in what is called the Schodinger’s box experiment. It is really a thought experiment because to my knowledge nobody has attempted to run it. The experimental situation is this. You put an animal in a box with a vial of some poisonous substance that will be broken if a radioactive particle decays, which is a fifty-fifty proposition. So, before you open the box (the measurement) is the animal dead or alive? The answer is neither or both. What, surely an animal is either alive or dead? An exception might possibly be suspended animation, but there is no way of telling if the particle decayed before the opening of the box (the measurement). So, when you open the box (the measurement), you determine whether the animal is alive or died. In this way, to bring in a bit of ethics, it is you that has either saved or killed the animal when you open the box (the measurement). Of course, the whole experiment could be seen as unethical. By the way, in the original experiment it is a cat in the box. I am using the generic animal here as not to upset Baxter, if he were to read this blog.
There are two main philosophical approaches to attempting to solve the measurement problem with its weirdness, one of which is even weirder than the original problem in the first place.
One is called complementarity. It was proposed by Niels Bohr, one of the founders of quantum physics, who played both a theoretical and a mentorship role in the founding of quantum mechanics. Complementarity, as I see it, is the view that both aspects of a particle (its waviness or its particleness) have an equal standing; it all depends on your interest or purpose. I suppose this makes it a pragmatic stance. Pragmatism is the philosophical approach to truth where what is true is to be found in what is useful or in what works. So, as a deep answer, or as an exact solution to the wave/particle duality issue, it is not very satisfying to me. This could be considered a personal weirdness because as far as personal action is concerned I often think that pragmatism is the best approach. But, after all, I am not a quantum object. You could say in deciding what to do pragmatism is in its true element.
The other solution was offered up by Hugh Everett III. It addresses the measurement problem more directly. It is called the many worlds solution, and it maybe crazy enough to be true, but who knows.* This solution maintains that when a measurement is made both or all outcomes occur. The world in effect splits up. In one world the animal is alive, in the other its dead. So, in this solution there is no weirdness going on in either world. But, and this is a big but, in my mind it spreads the weirdness to all worlds combined together.
There is one more thing I would like to say on the measurement problem. There are some, scientists among them, that believe it is human consciousness that determines what has and will occur in the universe because of the attempt to interpret the Schodinger thought experiment. To them, if I understand it right, it is the human act of measurement that actually determines or gives an exact solution to any quantum event, and since there are a great many of these, it ends up that without human consciousness to observe (make measurements) nothing would occur at all, so humans are necessary for the universe to have a determinate existence.
This, in my opinion, is just human hubris. Can we really say we are necessary for the universe’s existence? It seems unlikely in the extreme. I am not aware of any experiment that could possibly tell if this were so. I also think it is unnecessary that consciousness needs to enter the picture at all. This is because the interactions, including a measurement, above the quantum level is what determines the outcome of any quantum event. I could be wrong, but I have not heard anything to the contrary.
Okay, enough of all these measurement issues. Spooks anyone? Albert Einstein, known for special and general relativity theories, was one of the originators of quantum physics, and worried a lot about the spookiness of quantum physics. He could not except that certain quantum systems implied” spooky” action at a distance, thereby bypassing the rule that no signal can travel faster than the speed of light. He purposed, along with two other scientists (Boris Podolsky and Nathan Rosen), what is called, after their initials, the EPR thought experiment. In this experiment two quantum particles are entangled, basically meaning that if one were to spin in one direction, the other one would be spinning in the other direction. The original EPR experiment I believed used polarization, but particle spin works just as well or better for understanding it. Actually, particles do not spin the same way macro objects spin, but that does not matter here. Anyway, after the particles are entangled they go off in different directions, and after the distance between them would not allow for any signal faster than the speed of light, a measurement is made of one of the particles. If the spin is say down, then it is determined at once that the other particle’s spin is up. How could this be done without gaining information of the particle’s spin faster than the speed of light. Einstein and his colleagues said this could not be right, and there had to be something wrong with quantum theory because of it.
In the 1960s a theorist named Eric Bell developed an inequality that showed if the EPR experiment was correct than there had to be that spookiness at a distance. It so happen in the 1980s an experimental physics, Alain Aspect, carried out the experiment and the results confirmed Bell’s inequality. So, Einstein and his gang of three were wrong and quantum theory stands without change to this day.
Einstein just could not bring himself to fully except quantum physics, despite his early contribution. He stated, “God does not place dice with the universe” This was not a declaration of his belief in god, whatever that might have been. One thing is certain he was not a theist—a person who believes in a personal god. He appeared to believed that the act of doing science (probably meaning the theoretic side) was equivalent to an act of spirituality. Anyway, he made this statement because he could not believe that there was indeterminism deep down in reality. However this may be, the equations used in quantum mechanics are deterministic as are all mathematical equations. This includes probabilistic equations. You plug in the numbers and out come a determinate result. The answers are the same every time you plug in the same exact numbers. I say exact (and I mean exact) to avoid computational chaos.
I want to address another issue about the indeterministic aspects of quantum mechanics. Some people argue that this provides a way for free will to be active in human decision making. The major strike against this idea is that indeterminism does not grant a free choice; it grants a random choice, so that free will becomes willy-nilly. Another strike against it is once the macro level is reached it is cause and effect all the way up.
I will very briefly mention that I think there is a role for free will to play, but instead of some kind of strange decider, it is an emotion or feeling. In this role it is the initiator of all our caused actions.³
Is there any more weirdness about in the quantum world? Oh, yeah. There is what is arguably the most famous of all quantum principles. It involves measurement too. It is the uncertainty principle, discovered by Werner Heisenberg, who worked with Niels Bohr. It states that one cannot measure two link quantities at the same time with absolute precision. The most common mentioned example concerns the quantities position and momentum. In this example if you measure the position of a particle with exactness you cannot measure its momentum at all and vice-versa. The reason for this is that when you measure a particle you cannot help but disturb it. By measuring the position you disturb the momentum. When you measure something at the macro level you do indeed disturb it, but it is so minute it does not matter for all practical purposes. A few other link quantities are time and energy, electric field and polarization density, and magnetic potential and electric current. Position and momentum are the most commonly discussed quantities because with them it is easier to comprehend the quantum effects of the uncertainty principle.
Where is it? “I cannot be in two places at the same time” is a common answer to a request. Well if you are a quantum particle you can. This aspect of quantum physics is being used to explore the creation of quantum computers. All normal (non-weird) computers operate serially. They only carry out one operation at a time. However, because a particle can be in multiple positions before a measurement is made, a quantum computer should be able to carry out a great many operations at the same time. This increases the speed of operation massively (reverse pun), so instead of carrying out one operation at a time, a quantum computer would go through all operations at once.
There are a number of problems that we currently are not able to solve. One important problem involves factoring a very large number into two prime numbers. The reason why this is important is that modern computer security that protects information that you want to exclude others from accessing, such as bank accounts and health data, is based on this factoring. When (most researchers do not think it is a question of if) a quantum computer is fully developed to carry out such an operation this type of security will be compromised, and the protection we now enjoy will be gone. Hopefully, by the time this occurs there will be a newer and improved version of security that will not depend on prime factoring of very large numbers.
Is reality continuous or discrete? Well, our world certainly looks smooth—but. At the quantum level the weirdness continues; at this level the world appears discrete. There is a lot of quantum jumpiness going on. Niels Bohr (mention above) found that in a hydrogen atom, the simplest of atoms to work with, electrons are found only at certain energy levels, never at any level in between. They jump between energy levels. Naively, these energy states are called electron orbits, but that is particle talk. Remember, the electron is both particle and wave or neither.
There are a bunch of discrete aspects to the quantum world. These aspects were discovered by the physicist Max Planck, the first to discover anything about quantum physics. These aspects are all connected with Planck’s constant, which is the basic unit of energy that a particle can carry. These energy units only come in discrete measures. You could say that they represent packets of energy, or quanta, which is where quantum physics gets its name. It is because a particle’s energy only comes in these packets that the energy levels of an electron in an atom are found only in particular levels and at no other levels in between.
There are also, based on Planck’s constant, the Planck length and the Planck time. With the Planck length there can be no smaller length than this length. This means that there will always be gaps at the quantum level. We think of length as being continuous, but this only applies at the macro level, not at quantum sizes. As with the Planck length, the same is true of time. The Planck time is the smallest unit of time possible. Again, we think of time as continuous, but this is only apparent above the quantum level.
Are you feeling jittery now that you know things are not as smooth as they appear? Why can we not detect all this discreteness? It is because we are not ourselves quantum size beings. I suspect if we were, we would feel time as jumpy, length as broken up into pieces, and energy only coming in bits. If you were the size of an electron you would probably find nothing weird going on. As Richard Dawkins has expressed it, if we evolved to operate under quantum level conditions, than we would find it is the normal way of things. We would probably think the macro level is where all the weirdness is occurring. So, you could say the weirdness is a matter of viewpoint, literally.
Because of quantum discreteness, I think it is wrong to think of the origin of the universe as the “big bang”. After all, this label was given by Fred Hoyle, an opponent of expansionism in cosmology. He was for a steady state universe. I think it is because of this discreteness that to say the universe started from an infinite point of energy, size, and time is not correct. There had to be a smallest energy state to start with, as well as, a smallest size and no smaller and a shortest period of time and no shorter.
So, the beginning of the universe because of quantum effects at that time is even weirder than if it all started from an infinite point of energy, time, and size. This means that even the beginning, if you can speak of a beginning, is just plain weird. But, this I feel also eliminates the need of some cause outside of the universe. No god need apply—the job has been eliminated.¹ It appears, but is not certain that the universe began in a quantum event of virtual particles interacting in a vacuum.
Should we be concerned about all this quantum weirdness? And as a reminder, I have not covered it all or in much detail. Well, I for one am not. Jim Morrision may have been right: “People Are Strange.” Personifying the universe, it is strange, but it may not be strange enough, so any replacement theory if it ever appears maybe even stranger.* Of course, people are strange enough without all this quantum weirdness going on.
My major reason for not staying up all night in a state of angst actually involves the weirdness of the EPR experiment. This is because once the particles have the interaction that occurs between them (become entangled) their states are fix until there is some further interaction, such as a measurement or an encounter with another particle. So, it is because of quantum entanglement that I can leave all the weirdness where it belongs—at the quantum level—and live my life as if it did not matter.
It is also my feeling that there is plenty of weirdness for the macro world to play with. People are strange. I am strange. Baxter is strange. Okay, Baxter may not be a person, but morally he should be accorded personhood up to a point. Maybe personhood will be the topic of a future blog. Does it come in degrees, so other animals other than the human kind, for instance, have some of the properties of personhood?
I will leave you with a non-quantum weirdness I think about from time to time. Are bodies are made up of individual cells, grouped together into organs. Most of the organs besides the skin (yes the skin is an organ) we are hardly aware of unless there is something wrong (e.g. heart attack, heavy breathing, or tummy ache), but we are never aware of the individual actions of any of our cells. After all, there would be plenty of action to be aware of. Cells are so busy, it puts the average (maybe even are most advanced) factory to shame. For even more weirdness at the cellular level we have more bacterial cells on and in our bodies than actual cells we are composed of. Wee-ah-ooo.
¹ For a bit more on deism see my blog – Why Deism Is Not the Answer?
² For more on polytheism see my blog – What If There Were a Virtual Infinity of Gods?
³ For more on free will as an emotion see my blog – Why Are People Afraid of Their Brain?
* Niels Bohr once supposedly said: “Your theory is crazy, but it’s not crazy enough to be true.”