Tal, a conversation with an alien (9 page)

They could know the future.

Yes, now imagine your species in a few million years, designing massive computers the size of planets, calculating the position of all particles and their trajectories. If your computers became powerful enough, they could predict the exact configuration of the universe in the next moment, and if they could do that, since they know the exact configuration of that moment, they could predict the next moment, and from that information the next moment.  In other words, a sufficiently advanced civilization, with a sufficiently advanced computer, could know its exact future. They would know the future not due to divine will, but by their own technological creations.

I could see that being an encroachment on the playground of the Gods, if you believe in them.

Well yes, these last few arguments are philosophical, and your religion of science believes in experiment and logic.

That is correct, and you mentioned a scientific explanation.

Lux Aeterna

Yes
. And that scientific explanation will uncover the hidden dimension that I can observe. To understand the nature of this hidden dimension, you will need to understand one more thing, and that is the nature of light. For thousands of years, the central question concerning light was whether it was a wave or a particle. Did light exist as an unbroken wave of energy, or as little individual packets of energy?

I belie
ve quantum theory states that light is actually both.

During
Einstein's time, lacking the proper tools, scientists believed light to be a wave only. People think of Einstein primarily as the father of relativity, but it was his experiments with light that won him the Nobel Prize. Einstein, building on the research of great scientists such as Max Planck, showed that light was a particle; it could be broken down into single packets of energy, or quanta. Yet experiments up to then proved that light was a wave. It's hard to relate to light, so initially it doesn't seem so strange that it could be both, but this fact leads to some very odd conclusions. Often, before there is scientific proof, great thinkers come up with beautiful ideas. Even back in the 1700's Isaac Newton believed that though they seemed different, matter and energy were interchangeable. And Einstein's well know E equals MC squared implies a relationship between mass and energy. So it is not surprising that since light has a dual nature, matter must also have a dual nature.

This
does seems like a pretty radical idea that I never completely understood. Light can behave like a wave, but I don't see all the objects around me behaving like waves. I do not see myself as behaving as a wave.

Think
of a particle the way you think of a baseball. In the classical sense, you know where the baseball is when you look at it, it is in one place. You can also know how fast it is moving if you measure it. Now think of a wave. A wave is spread out over many coordinates of space. It has a wavelength and an amplitude, but it has no definite position that you could say is its only position. Another interesting point about waves is that you cannot add them as you do particles. If you take 10 baseballs, you can put them together and get something that is the size of 10 baseballs. You cannot do that with waves. Sometimes adding waves together gets you a bigger wave and sometimes they cancel each other out and you get smaller waves, or no waves at all.

I understand the difference, but I don't see
matter as waves. Matter is particles, atoms, molecules, and baseballs.

How do y
ou model the action of a system, like an electron or a bus? You can describe what you see: it is going fast, or slow, accelerating or decelerating, but these are approximations. In order to accurately model the actions of a system, you go beyond your senses, you use mathematics. For instance, Newton's second law states that force equals mass times acceleration. Using this equation, you can know an object's force, mass or acceleration if you know the other parameters. If one of the parameters, such as force exerted on a system changes, you can plug that into the equation, and know how the acceleration of that system will change. Thanks to the use of very advanced mathematics and sensitive measuring equipment, scientists have become very good at predicting what will happen to matter; even at the smallest scales. In quantum mechanics, scientists have developed different mathematical models, equations, and matrices, to predict where particles will be in their next space-time location, but these equations are much more complicated than Newton's equations.

Yes
, I know that mathematicians use functions to predict the actions of systems. You put in some values and get a changing result.

That is right,
and in the mathematics of quantum mechanics, matter can be defined by what is called its wave function. This is a mathematical equation that predicts where a particle will be in space and time. The most famous equation of this type is the Schrödinger wave equation. In 1926, Erwin Schrödinger formulated this equation, which describes the motion of any system, predicting how it will change through time. The main difference between Schrödinger's and Newton's equations is that Newton's equation gives one specific answer, one definite location for an object. While quantum mechanical equations like Schrödinger's do not, they give a range of possible answers.

I have heard of the equation, it is very complic
ated and its derivations even more so.

Yes, basically, you plug in the forces acting on the particle
and you will get a result that can be mapped out as a wave function. The function will take the form of a wave, with peaks and troughs. The equation is indeed very complicated, even finding a wave function for a single molecule in one dimension of space is a challenge to university physics students. Trying to figure out all of the parameters acting on an object becomes nearly impossible for larger objects, yet, since it works for one or a few molecules, it theoretically works for many. Schrödinger's equation doesn't even take into account certain aspects of relativity, or the collision and creation of new particles. There are other, yet more complicated equations for describing those possibilities.

Why don't we see waves in larger
objects then? Are these purely mathematical manipulations?

Well one interpretation is that the wave
that and object makes is not a real wave; it is actually a probability wave. All systems, great and small have a mathematical probability wave function that defines their motion. Matter as a probability wave means that though we cannot know for certain where the particle will be, we can know the probability that the particle will be in one place or another, depending on the values of the wave function. This answer gives no concrete place, only possible places, and the probability that the particle will be in each of those places. This explains the phenomena of quantum tunneling; when an object can seemingly pass through a barrier it should not be able to pierce. A particle will most likely bounce off a barrier, but because all particles behave as a wave, some part of the particles probability wave could reach past the barrier itself, hence the particle has a chance of being on the other side of the barrier. This is the quantum tunneling effect so necessary in many semiconductors. 

Ok
ay, so matter can be described by mathematics as a probability wave, but we really don't understand why it behaves this way, just that it does?

Interpreting
what the math means is important. In the end math needs to make sense to you, otherwise, it is literally just numbers. The basic equations of the past like Newton's laws of motion are pretty easy to grasp. You understand them concretely in your mind because they represent a physical fact you can observe. The Schrödinger wave equation maps the motion of a particle, but it gives multiple results, a wave of positions for one particle; though you actually observe one position for one particle. Therefore, the equation is not what you observe in real life. The big problem with the Schrödinger equation is the fact that there is no second part to the equation; some other mathematical pyrotechnics that will provide one concrete result from the myriad of possibilities. You see one concrete result in the real world, not a wave of results.

So what happens to the other
possibilities that do not occur? Are they simply thrown out? It does seem that perhaps there is something missing in our knowledge, some part of the equation that would give us one concrete answer.

Einstein
and even Schrödinger himself understood that his equation could make accurate predictions, but both believed that behind the equation, there must be some underlying effect, some information that would illuminate the next position of the particle precisely. The Schrödinger equation was just the best they could do at the time. They still believed that God did not roll dice. Yet in the nearly one hundred years since the debate began, no such information has appeared, the universe does seem to behave inherently randomly.

If there is no such
information, what does the probability wave actually mean?

The Double Slit Experiment

I have been presenting these concepts in a sort of abstract mathematical way, so let me explain it to you again in the context of an actual physical situation.

If you think it will help.

I think it will. One thing I like about humans is that you can explain something in one way, and then another. That combination helps their understanding. Like seeing things from two angles gives you a better understanding of space. So you have mathematics describing particles as waves, yet you do not usually see particles as waves. The reason is that particles only behave as waves when you aren't looking. 

What do you mean?

Just like the Invisible Boy in the super hero comedy 'Mystery Men', whose power is that he can become invisible, but only when no one is looking; particles behave as waves, but only when no one is looking. Hence, in order to see the wave, we need to not look at it.

--
This last reference caught me by surprise and broke me out of my intense mode of analysis. It brought me back to the reality that I was speaking to someone who claimed he was from outer space.

I find it curious that an alien would be so
familiar with our pop culture. Charlie Brown, Survivor, Mystery Men? I haven't even seen that movie.

Do you feel that
an alien should only go around quoting Shakespeare? I have the ability to process a lot of information. When studying humans, wouldn't you think that I would be interested in what the majority of a human population find entertaining, even if that thing only had its moment and then passed away with the humans who enjoyed it? Great art may transcend paradigms, but popular art defines them. And only on rare occasion is great art completely accepted or understood in its own time. I have an interest in many types of ideas. The ideas that blaze hot and fade away, and the ideas that linger at a cool burn. Besides, when communicating with humans, it is usually more effective to use references from their current pop culture, plus some of those references are truly entertaining. In this case, the reference is very fitting. It is disappointing that you, as a long-time member of this paradigm are unaware of this very amusing reference. But even if it is of no use to you now, it may aid your understanding some evening when you are flipping through the channels on your television and 'Mystery Men' happens to be on. Perhaps you should get another cup of tea, and I will return to my story?             

A
ll right. 

--
He waited until I poured my tea from the teapot and continued.

There was an experiment done
with light in 1799 that paradoxically allowed you to actually observe the phenomenon of not observing. It was called Young's experiment. It has since been refined, and is now repeated in almost every college physics class in the world with not only photons of light but many types of particles. It is now better known as the Double Slit Experiment.

Yes, I have read about this experiment, and it is included in man
y lay books about quantum theory.

What do you remember about it?

I remember it all: Single photons were fired off one by one into a chamber. The photons could go through one of two slits. One to the left and one to the right. Behind the slits was a board that absorbed the photons. Photon detectors were placed at the entrance to both slits. When experimenters looked at the pattern of the photon strikes behind the slits with detectors on, it made a definite pattern of dots behind one slit, and dots behind the other slit. 

That is the logical result. I
f you have half of the photons go through one whole and half through the other, after a while, you will see a pattern of two clumps of dots on the paper behind each whole. This would be a pattern made by a particle. If you throw baseballs through two slits and against a wall behind them, the baseballs will all hit the wall in a clumped pattern in the area directly behind the slits.

Yes, and h
ere was the strange result of the experiment: when they let the particle shoot out, but turned the detectors at both slits off, it created an interference pattern on the wall behind the slits. A pattern of particles in vertical stripes or lines, not clumps of dots. And some of these lines were not even directly behind the slits. Some photons were striking the back of the wall in places they should not even reach.