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Our future, our universe, and other weighty topics


Thursday, August 13, 2015

Electromagnetism is Algorithmic and Exquisitely Balanced (Part 2 of 2)

Two of the main forces that help keep the universe orderly are gravitation and electromagnetism. In Part 1 of this 2-part post, I explained why electromagnetism is algorithmic, in the sense of involving “if/then” logic. Now let me justify the claim that electromagnetism is exquisitely balanced.

There are two major reasons for making such a claim. Let me explain the first such reason, which has to do with the relative strength of electromagnetism. Electromagnetism is one of the four fundamental forces of the universe. If you do a Google image search using the phrase “relative strength of four fundamental forces,” you will find quite a few tables that compare the strength of these fundamental forces. The tables typically give numbers like this:

Fundamental Force Relative Strength
Strong nuclear force 1
Electromagnetism 1 divided by 137
Weak nuclear force 10-6
Strong nuclear force 10-39

We see here that electromagnetism has a very specific strength level that is about a trillion trillion trillion times stronger than the force of gravitation. Referring to the short-lived stars known as blue giants (which don't last long enough to support planets where life evolves), and to the type of stars known as red dwarfs (generally regarded as being stars not as suitable for Earth-like planets as yellow stars like our sun), the physicist Paul Davies says on page 73 of The Accidental Universe: “If gravity were very slightly weaker, or electromagnetism very slightly stronger (or the electron slightly less massive relative to the proton), all stars would be red dwarfs. A correspondingly tiny change the other way, and they would all be blue giants.” So apparently the existence of sun-like stars depends on electromagnetism having a level of strength very close to its actual strength. 

We also know from consideration of the atom that the electromagnetic force is finely tuned. There is an electromagnetic force of repulsion between the protons that make up much of the nucleus of an atom, and the nucleus holds together only because there is a strong nuclear force holding protons together (along with neutrons). That strong nuclear force is only about 100 times stronger than the electromagnetic force.  A fairly small increase in the electromagnetic force would cause atoms with more than 6 protons in their nucleus to become unstable because of the electromagnetic repulsion between protons.  In such a case the calcium in your bones (not to mention the iron in your blood) would be radioactive.  A fairly small decrease in the electromagnetic force would mean that electromagnetism would be insufficient to allow for the complicated molecules on which life depends.

So apparently our universe lucked out with the strength level of electromagnetism that we have. This is one way in which electromagnetism is exquisitely balanced. But there's another way, which pertains to the strength of the charges on the proton and the electron. At the subatomic nature there is great uniformity, in the sense that each electron is exactly like every other electron, and each proton is exactly like every other proton. Each proton has a mass 1836 times greater than the mass of each electron. If one knew only of this fact, and knew nothing about how strong the charges are on these particles, you might guess that the charge of a proton is about 1000 or 2000 times greater than the charge of each electron. But that is not the case. Instead, the charges are exactly the same (although by convention – a not really warranted convention – the charge of an electron is called a negative charge). 

According to scientists, the charge of the proton is 1.60217657 ×1019 coulomb, and the charge of the electron is 1.60217657 ×1019 coulomb. This scientific paper is by a scientist who used a molecular beam deflection method to conclude that the proton charge and the electron charge have a magnitude differing by less than 5 parts in 10,000,000,000,000,000,000. 

The chemistry on which life depends could not exist if the magnitude of the charge on the electron did not match the magnitude of the charge on the proton. It would require only a small difference between the two to make planets unstable (not surprising because electromagnetism is a force about a trillion trillion trillion times greater than the gravity that holds our planet together). 

In his book The Symbiotic Universe, astronomer George Greenstein (a professor emeritus at Amherst College) says this about the equality of the proton and electron charges:  "Relatively small things like stones, people, and the like would fly apart if the two charges differed by as little as one part in 100 billion. Large structures like the Earth and the Sun require for their existence a yet more perfect balance of one part in a billion billion."  

So we have the second reason why electromagnetism is exquisitely balanced. But it would be easy for you not to notice this second reason, because scientists use a little semantic convention that almost seems to have been designed to hide or cover up this exquisite balance.  The semantic convention is one that involves failing to list the proton charge and the electron charges as separate constants, but referring to them as a single constant called the "elementary charge."

We can see how this is kind of a cover-up by considering an analogy. Imagine that your parents were born on exactly the same day and the same hour. If you listed those two times and dates of birth in a table like the one below, it would really catch your attention, and might make you think that perhaps some meaningful synchronicity was involved. You might think to yourself, "This isn't just a coincidence."



Father's birth place San Diego, USA
Mother's birth place Toledo, USA
Father's birth date/time January 22, 1990 10:37 PM EST
Mother's birth date/time January 22, 1990 10:37 PM EST
Parental assets $22,035.00

But imagine you wanted to hide this coincidence. You might instead list this data in the following table, which someone might read without noticing any coincidence.


Father's birth place San Diego, USA
Mother's birth place Toledo, USA
Parental birth date/time January 22, 1990 10:37 PM EST
Parental assets $22,035.00

 Here we have a little trick in which the two separate birth dates and times of the parents are listed under a single row marked "Parental birth date/time."  This kind of hides the coincidence of the exact match (or at least makes it much harder to notice). 

Scientists use a very similar little trick in listing the fundamental constants of nature. A typical table listing the fundamental constants will start out looking something like this (with the charge of the proton and the charge of the electron represented by a single row labeled "elementary charge"):

Gravitational constant 6.67384(80)×10−11 m3·kg−1·s−2
Planck's constant 6.626 069 57(29) × 10−34 J·s
Proton mass 1.672 621 777(74) × 10−27 kg
Electron mass 9.109 382 91(40) × 10−31 kg
Elementary charge 1.602 176 565(35) × 10−19 C

But this is the same kind of trick as the "parental birth date/time" trick mentioned above.  There is no physical basis for assuming that the charge of the proton and the charge of the electron are the same actual thing -- they are instead two separate things that happen to exactly match.  The honest, correct way to list the above constants is as follow.

Gravitational constant 6.67384(80)×10−11 m3·kg−1·s−2
Planck's constant 6.626 069 57(29) × 10−34 J·s
Proton mass 1.672 621 777(74) × 10−27 kg
Electron mass 9.109 382 91(40) × 10−31 kg
Proton charge 1.602 176 565(35) × 10−19 C
Electron charge -1.602 176 565(35) × 10−19 C

 When we see the constants listed as above, we suddenly notice  the coincidence of the proton charge and the electron charge matching exactly.  The actual match is not just to 10 decimal places (as indicated in the table below), but to at least 18 decimal places. 

Electromagnetism (upon which all life depends) is algorithmic, involving "if/then" logic (as I explained in Part 1 of this post).  Electromagnetism is also exquisitely balanced, for the two reasons given in this post.  The exquisite balance of electromagnetism is comparable to what we would have if an obelisk the size of the Washington Monument was balanced on its top. 


Electromagnetism is only one aspect of physics, which is only part of science. But it would seem that electromagnetism by itself has an intrinsic ingenuity and extreme fine-tuning that is sufficient to suggest weighty philosophical implications.