links

In a series of four blog posts I explained my philosophy of "as if": #1, #2, #3, #4

Donald Hoffman asks if we see reality as it is (spoiler: No)

Veritasium about electricity and relativity.

Numberphile about and with Terence Tao and Jim Simons.

free will #4

We use the idea of 'free will' in our daily lives, politics, the justice system, economics, religion etc. and also the Copenhagen interpretation of quantum theory assumes an observer with 'free will'.
However, it is not difficult to see that it is a flawed concept (left as an exercise to the reader).
Perhaps Schopenhauer said it best: I can do whatever I want, but I cannot want what I want.
But on second thought (!) it becomes clear that the terms "will", "want" and "I" are not even well defined.

We do not have a theory that would explain our conscious (or unconscious) experiences, but we assume a direct connection between the activity of our brain(s) and our state of mind(s). However, this assumption also suffers from an obvious flaw: If our brains consist of molecules, electric fields etc. then physics should describe all of its properties. Obviously, physics does not contain anything that would describe our feelings or what has been called 'qualia'. Even if we would have a complete description of a dog's brain, we would not know what it feels like to be a dog ... this is of course known as the 'hard problem of consciousness'

------

Immanuel Kant, concluded that we have to live "as if" we have free will.
We all live "as if" life has meaning ... and I write "as if" somebody is reading this.

physics #3

The best theory physics has to offer is known as 'the standard model'; it consists of quantum field theories on a classical space-time geometry and describes the physics of our world from elementary particles to galaxies.
It is obviously very useful, but is also known to be seriously flawed:
i) The quantum field theories become inconsistent at very high energies.
ii) The combination of quantum theories with general relativity is only an approximation, which breaks down in several cases, e.g. when the interaction between quantum fields and space-time cannot be neglected.
iii) The evolution of quantum fields leads to the superposition of macroscopic objects (Schroedinger's cat) and therefore the superposition of different space-time geometries. There is no agreement how to handle this and how to make sense of it, which is known as 'interpretation problem' or 'measurement problem'.

There is some hope that one day we can find a better theory and there are hints that a theory based on superstrings could solve the problems of 'the standard model'.
However, we are far from being able to perform experiments that would help us figure this out ...

The history of physics is a series of increasingly useful, but flawed theories.
It began with the epicycles of Ptolemy, followed by the classical physics of Newton et al., and finally relativity and quantum theory, culminating in 'the standard model'.
It is quite amazing how much our descriptions of the world changed over time; I think our attempts to resolve the flaws and inconsistencies of each era is mostly a struggle with our own biases ...

reality #2

I assume most people have a 'concept of reality' similar to mine: I live in a large universe, which contains galaxies, the solar system and our planet Earth. My body contains a human brain, which creates my conscious experiences based on sensory input from my eyes, ears etc.
Of course, the universe evolves and physics describes the movements of the various parts of the universe, from atoms to the galaxies.

This 'concept of reality' is very useful and therefore we acquire most of it already during childhood, but it is not difficult to see that it is deeply flawed.

An important part of the concept is the idea of evolution and change, which means that we (have to) divide reality into the past, which no longer exists, the future, which does not exist yet and the present, an infinitesimal sliver of existence.
I think Aristoteles was one of the first to articulate the paradox of time and the fact that only an infinitesimal part of reality actually exists.
Augustinus wrote: "What then is time? If no one asks me, I know what it is. If I wish to explain it to him who asks, I do not know."
His statement is of course equivalent to saying that 'time' and our 'concept of reality' is very useful, but actually flawed.

However, we need to go a step further and consider an important insight from the theory of relativity, which provides us with this causal diagram:



The theory tells us that the infinitesimal sliver of the present shrinks to a single point, the 'here and now' (somewhere at the center of the red ring), surrounded by past, future and space-like events. It is quite obvious that 'my brain' and not even a single atom would fit into this point.

There is a big problem with our 'concept of reality' if none of it actually exists ...

However, sometimes the assumption is made that all of space-time somehow exists and the diagram just displays the causal relationship of events, which are all real; I think that e.g. Hermann Minkowski believed that.
Unfortunately, this point of view would be in conflict with quantum theory (more about that in a another blog post), but worse, it does not really solve the problem.
In fact it is just a play with words: Of course I can imagine that future events already exist somehow, but this does not change the obvious fact that I have no direct experience of them. The same is true of events from the past and I cannot have direct experience of space-like events.
So the 'here and now' is the only part of reality I can directly experience - but it is a single point only.
And it is the point at which I realize that my 'concept of reality' is just as flawed as the 'concept of a refrigerator' my dog used.

flaws #1

I believe that all our ideas, explanations and theories about the world are flawed, but some are quite useful.
This blog post shall be the first in a series to provide examples and explain my views.
Perhaps long term readers (if there are any) will notice that this is mostly a repeat of previous writings, but I thought it might be interesting to explain them under one theme ...

Many statisticians are familiar with the statement "all models are flawed, some are useful",
and the point of this series is to extend this insight to all our theories, even very basic ideas.

The philosopher Vaihinger, generalizing the philosophy of Immanuel Kant, was one of the first to embrace the insight that our explanations are often inconsistent, but that they are nevertheless useful in many cases and we can treat them "as if" they are correct.
I believe that it is necessary to extend this philosophy of "as if" to all our theories, explanations and ideas.
Perhaps some view this as a pessimistic view of the world and our role in it, but I think it can be liberating too ...

-----

While I am writing this, I am thinking about my dog.
Does a dog have 'theories' or 'explanations' for his experiences? What 'ideas' does a dog have about the family he lives with or the refrigerator with all this great food inside?
Whatever his 'theories' are, I am sure that they are deeply flawed, even if they are quite useful most of the time.
And perhaps there is even a 'basic idea' similar to 'I bark, therefore I am'.
But my dog would be wrong, because I no longer have a dog ...


Blog Archive