the whole world in your little TOE

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The whole world in your little TOE

Even in the highest spheres of natural science, humankind exists. When people began to dream of subjecting the entire spectrum of the observable world, from the smallest to the largest, to a universally valid formalism, the term 'Theory of Everything' was coined, along with the diminutive acronym TOE. To this day, this quest has remained unsuccessful.

One approach, 'string theory,' postulates six additional dimensions beyond four-dimensional space-time. This proposal has so far remained purely abstract. No one can imagine what such additional dimensions mean, let alone conduct concrete experiments to prove their existence.

One would only have to consider what all must 'be the case' for us (to quote Wittgenstein's 'Die Welt ist alles was der Fall ist'), to be convinced of a real state of affairs. Location in space and point in time, the 4 basic dimensions, are not enough on their own. Since Heisenberg at the latest, we have known that no facts can be secured without taking into account the observer. Each observation leaves its mark on the observed.

As if that weren't enough, a single observer is in a weak position. Since Immanuel Kant at least, we've known that no observation is absolutely reliable. Every observation requires independent confirmation. In a metaphorical sense, one could imagine observation as a one-dimensional event, and its confirmation as the addition of another dimension.

Now all that's missing is a scientific collective that can bring all the individual observations together and craft something of general validity from them. Without air resistance, the speed of a falling body increases with the square of the distance traveled. All the consistent individual observations are extrapolated into a space of possibilities with the prediction: Whoever, wherever and whenever, investigates this specific relationship (falling speed and distance traveled) will find the same formalism confirmed.

Perhaps these are three of the additional dimensions proposed by string theory. But would that do justice to 'true' reality? Even the most intelligent collective remains fallible. We've known this since Sir Karl Popper at the latest. All 'knowledge,' however certain it may seem to us today, is provisional and not immune to being overturned or at least refined in the distant or near future.

One may be led to suspect that the ten dimensions suggested by string theory are not as ambitious as they seem at first glance. If one wants a 'Theory of Everything,' one must also expect to reach the limits of human imagination.

Where are these limits? The last 100 years or so have taught us that exact science has its limits. The best thing you can say about serious science is that it recognizes the limits of its validity (think of Kurt Gödel's incompleteness theorem). Beyond these limits, chance takes over.

Quantum theory gives this chance its due. However, it also presents us with some oddities that don't quite fit into our traditional worldview. The indeterminacy of chance contrasts with the property of particle pairs, which maintain their relationship to one another with astonishing perseverance over great distances and periods of time ('entanglement').

Isn't it touching how science continually finds expressions for the seemingly inexpressible? Such a paired particle may follow its lonely path until - discomforted by an unintentional encounter - it is forced, for the first time in its more or less long 'life,' to reveal itself as the bearer of a specific property, of which there are only two possible. (If it had the honor of participating in an experiment, the encounter was, of course, not unintentional.)

What sounds like an exotic phenomenon brought about by resourceful researchers could well be commonplace in the universe. We know of natural processes that constantly generate such pairs. One example is the positron-electron collision, which results in a diverging photon pair (Ivashkin et al. 2023). The typical 511 keV signature is found particularly in the galactic center (Prantzos et al. 2010).

It's hard to imagine that after positron-electron collisions in stars, both generated photons would continue their trajectories undisturbed for long. More likely, one would disappear into space and the other into the star's interior. However, positrons are also present in cosmic radiation (Adriani et al. 2009). If such a positron collides with an electron in empty space (e.g., a grain of dust), the two photons could drift apart undisturbed for a long time. Space could be teeming with entangled particles, but no algorithm is conceivable that would allow the identification of the respective partners.

But just because we can't find them doesn't mean they're meaningless. There's more between heaven and earth than we can imagine. Fortunately, the string model still leaves us with three more dimensions...

Adriani O, Berbarino GC, Bazilevskaya GA, Bellotti R, Boezio M et al (2009) An anomalous positron abundance in cosmic rays with energies 1.5-100 GeV. Nature 458, 607-09

Ivashkin A, Abdurashitov D, Baranov A et al (2023) Testing entanglement of annihilation photons. Sci Rep 13:7559

Prantzos N, Boehm C, Bykov AM, Diehl R, Ferrière K, Guessoum N et al (2010) The 511 keV emission from positron annihilation in the galaxy. Rev Modern Physics 83.1001

MB (12/24)

The idea of taking social phenomena into account in the search for a comprehensive, formalized description of reality has occupied me since 1989 (in German only).

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