Causality: Founded on Bedrock, or in Quicksand? Part One

Every effect has a natural cause which preceded it in time. You live your entire life confident in the reality of that principle. If you do (or don’t do) such-and-such, a further down-the-track such-and-such will (or won’t) happen. If any violation of that principle happened to you, you’d come to doubt your reality, thinking instead you’d entered “The Twilight Zone” or the world of “Alice in Wonderland”! Yet, sometimes scientists will tell you that something happens for no reason at all.

The logical connection between cause and effect (causality) is one of the, if not the, most fundamental principles in the physical sciences*. If A happens, B follows. For every action there is an equal and opposite reaction. If an electron meets a positron – ka-boom! If sodium reacts with chlorine, you get table salt – not some of the time, but all of the time. Stars larger than a certain mass will end their stellar lives in a supernovae explosion. Solar and lunar eclipses, the tides, sunrises and sunsets can be determined with high accuracy mega-centuries in advance. You’d be in shock if you fired a bullet at a piece of tissue paper and it bounced back off and hit you, to say nothing of firing up the kettle for your morning coffee only to find ice inside instead of boiling hot water afterwards. Our entire lives are based around the certainty and predictability of causality. If things happen, they happen for a reason, even unusual or unexpected things. See, you weren’t aware of the steel plate behind the tissue paper, or that your better half played an elaborate joke on you having previously stashed an identical kettle in the fridge and performed some slight-of-hand! Anyway, and easily verifiable, you’ll see that physical science textbooks contain many thousands of examples of everyday, and not so everyday, cause and effect situations.

Causality is to me at least, a 100% certainty relationship. It’s not a 99.99% of the time relationship. That is, if A happens, B follows. If B happens, C follows. If C happens, D follows. Causality is not a case of if A happens, B or C follows. If C happens, D maybe follows. Now it doesn’t matter to me that causality can be reversed – if A happens, B follows. If B happens, A follows. That’s allowable because at the micro level the laws of physics aren’t time dependent. An electron and a positron can annihilate and form energy (in the guise of a gamma photon). A gamma photon can spontaneously form an electron-positron pair.

That 100% causality certainty suggests the following. There must be such a thing as predetermined or predestined outcomes. In the beginning were created trillions upon trillions upon trillions of matter particles (electrons, etc.) and force particles (like photons). They were all set in motion – in specific directions with specific velocities. The relationships between all of the elementary particles are fixed, and we call them the physical constants. The particles are fixed. The velocities and directions are fixed. The relationships are fixed - All else follows. Particle A has fixed properties.  Particle B has fixed properties. The relationship between particles of the A kind and of the B kind are fixed. Particle A meets particle B. If causality is fundamental, the outcome is 100% fixed; 100% certain. Thus, the initial ‘in the beginning’ set of conditions, once set in motion, will produce with 100% certainty, right on down the line, the exact sort of world or Universe we experience today. At the time of ‘in the beginning’, you became an inevitability. At least that’s one philosophy, but one I suggest must be so if causality is a valid concept.  

As a generalization, all of biology is ultimately based on chemistry. Chemistry is ultimately based on physics. Physics, at its fundamental core, is structured around mathematics and equations. Equations tend to equate things – obviously. Say 1 + 1 = 2, which in effect says if you cause two separate objects to come into an association, the effect is two objects in association with each other! Equations are also prediction devices. If you know the values of A, B, and C, you can predict D. If you then measure D, you find prediction (theory) and reality (fact) match – not every now and again, not only on weekends and public holidays, but all of the time. If you solve for D, knowing A, B, and C, you will have 100% confidence that in reality D is what you calculate it to be. That confidence can only arise if cause and effect operate 100% of the time. If cause and effect did not operate 100% of the time, then to use a well known literary example, Winston Smith could indeed believe that 2 + 2 = 5 and wouldn’t have to rely on Big Brother to ram the point home.

So, it’s surprising that there are those who suggest that sometimes things happen for no reason at all, like the origin of the Universe. First there was nothing; then there was something! Another example often given is an unstable radioactive atom, say an atom of uranium. It can remain in a unstable state for eons, then go ‘poof’, and for no [apparent] reason. I insert ‘apparent’ because I refuse to accept that the uranium atom goes ‘poof’ for absolutely no reason at all. But it is puzzling in that you could have two identical uranium atoms, sitting side by side, and one goes ‘poof’ and the other does not.

But then, let’s look at a macro case. Say we have two identical twins standing side-by-side. All of a sudden one keels over dead – the other doesn’t. Would you consider that mysterious? Probably not, as an autopsy might reveal that the one who kicked the bucket had a heart attack.

So, what about those two side-by-side ‘identical’ uranium atoms where one goes ‘poof’ and one doesn’t go ‘poof’. Did it happen for no reason? Unfortunately, it’s way more difficult to perform an autopsy on a ‘poof-ed’ uranium atom, but that doesn’t mean that it didn’t suffer the micro equivalent of a heart attack. I think the alternative to the ‘no reason’ argument is that there was some, ever so subtle and maybe in-deterministic quantum event that triggered the ‘poof’ in one. Perhaps something caused the phenomena called ‘quantum tunnelling’ inside the uranium atom’s nucleus forcing it to spit out an alpha or beta particle or maybe a gamma ray. The escape, the ‘poof’, turned the previously unstable radioactive atom into a stable non-radioactive atom. As a best guess, maybe the uranium atom that went ‘poof’ had its nucleus hit by a passing neutrino or cosmic ray that triggered the quantum tunnelling that caused the ‘poof’. We may never know exactly what that something was, but it was a something, not a nothing.

Akin to the radioactive atom example, there are those who suggest that quantum physics have undermined causality. That’s because in quantum physics one of the central planks is the uncertainty principle, better termed the Principle of Indeterminacy in the professional literature. In effect, the guts are that the very act of measuring something changes the characteristic(s) or nature of what you are trying to measure. A macro example would be you wanting to measure the temperature of your cup of coffee. Alas, sticking a thermometer into the cup in itself changes the temperature from what it was before you stuck the thermometer in.

A micro example – say there’s this electron travelling along minding its own business, and say you want to stick your nose into its business by wanting to know where it is now, how fast it’s travelling, and in what direction its heading. Now to detect this electron, something else has be interact with both the electron (firstly) and hence with you (or more likely as not your recording or measuring instrument). Unfortunately,  that interaction with the electron, say a photon hitting it and then the deflected photon being detected by you (or your instrument), knocks the electron away from the position it was in, changes its velocity and its direction or pathway you were interested in. You now ain’t got a clue where the electron is which is what you were trying to establish in the first place. Ultimately, the position, a combination of its velocity and pathway, become only a probable or possible or indeterminate or uncertain or even, to our perception, a random one. There’s a certain probability the electron is now within a certain range; a higher probability or certainty it’s within a larger range and a even greater probability it’s within an even greater range. Probably the only thing you’re 100% certain about is that it’s somewhere in the Universe! So even though you can’t know exactly where the electron is to the Nth degree, it’s somewhere and it’s in an exact place (has coordinates) and has a pathway, and there’s a reason behind it. That’s a micro example of say a small marble hitting a large marble and deflecting the large marble’s position, velocity and direction. There’s still cause and effect in operation.

What about the duality nature of light? Sometimes light (photons) acts like a wave, sometimes like a particle. [The same applies to other fundamental particles, like electrons.] Even though this is considered strange doings (to us anyway used to nature in the macro realm), there’s still no violation of causality. Identical experiments, regardless who, where or when performed, produce identical results. It’s just that experiment #1, #3 and #5 produce wave-like behaviour 100% of the time, and experiment #2, #4 and #6 produce particle-like behaviour, again, 100% of the time. If a total novice comes along and does experiment #2, you can bet particle-like behaviour will result. Confusing? Yes. Do we have a long road ahead of us before we come to terms with this duality and what nature is trying to tell us? Yes. Is wave/particle duality a violation of causality? No.

To be continued…

*In the biological sciences, even under the most tightly controlled laboratory conditions of temperature and pressure, etc., the experimental organism will do what it damn well pleases! (Nudge, nudge; wink, wink.)