Today we are going to take a quick look at some of the central absurdities of string theory. Some of you will already know about these, while others might like a quick refresher or not know as much.
We will also briefly refute these absurdities and in doing so show some of the reasons why they are so absurd.
Let us start with something central to string theory:
The number of dimensions that string theory says space-time needs.
In string theory, it is believed that to unify quantum theory and relativity and explain physics, there must be more than the three dimensions of space and one of time. How many further dimensions there is, is a matter of some debate, but it typically starts with about nine or eleven. But it goes as high as 26!
What does it mean for space-time to have dimensions? That somehow dimensions are a physical part of the universe! When as we have discussed before, they are simply mathematical abstractions.
There are two kinds of things that exist.
Abstractions and physical entities. If something exists it must be one of these, there is no third option. Physics studies the physical world, the entities that physical reality consists of. Those which are primary and are not abstractions. And it uses abstractions to do so.
The concept of a “dimension” is just that, a concept, that is an abstraction. It studies the relationships between entities. This is just an abstraction used to study those relationships and they have no physical existence.
Modern physics likes to pretend otherwise, as though the universe is somehow made from dimensions, that is abstractions. And that we observe the three-dimensions of space and one of time. But not the dimensions after the first four.
It claims that the reason we do not observe these “higher” dimensions is that they are “hidden”, somehow “rolled out of the way” so that they cannot be observed. This is alleged to be performed by resorting to mathematical trickery. But of course, all of that is completely unnecessary.
The reason that we do not observe these higher dimensions is that they are not observable as though they were aspects of the universe. We do not observe the three dimensions of space as though they were something we could see. For that matter, we do not observe time as though watching a clock tick is the same thing as observing time.
We do not observe any of the dimensions!
We do not observe these abstractions, at least not in the sense that we observe physical things. Dimensions are abstractions, not physical things that can be observed or even inferred to physically exist.
So, it is pointless to try to use complicated mathematics to rationalize why we cannot see the dimensions. Why should we expect to? They are not physical things, they are abstractions. It would make about as much sense to try to rationalize why we cannot see the concept of justice itself or why we cannot touch the concept of “likeness” qua the concept likeness.
String theory is itself premised on the notion that reality is made from one-dimensional “strings”. This makes no sense whatsoever. What does it mean for something to be “one-dimensional”? Nothing at all. This is mathematical nonsense.
Everything that physically exists (is not an abstraction) is a three-dimensional object. Electrons, quarks or atoms, if they physically exist, have three-dimensions. They have some height, depth and length (or whatever you wish to name each of the three dimensions).
Why? Every physical object has shape and that implies that it must have some extension in each of the three dimensions. Therefore, they are all three-dimensional. Dimension is a concept; it refers to the extension of an entity viewed from different perspectives.
If we take it to be true that physical entities are three-dimensional, then we must wonder how string theory can hope to help by postulating the existence of one-dimensional entities. Or, since physical entities cannot be one-dimensional, how does it help to discuss one-dimensional non-physical entities? How does it help to explain reality in terms of one-dimensional concepts?
Trying to explain our physical reality by reducing reality to a series of mathematical abstractions is of no help whatsoever.
Now let us consider the claim that string theory implies that there must be multiple universes, perhaps a practically endless number of them. As many as 10^500 of them. That is 10 with 500 zeroes at the end! That is an unimaginably large number!
This clearly makes no sense. The universe is simply an abstraction that refers to “everything that exists”. It is not simply a subset of existence or something of which there can be more than one. No, it is simply an abstraction that subsumes everything. We talk more about this in episode three of the podcast.
How can you have multiple of “everything that exists”? You cannot. How does string theory think it can away with saying that you can? It cannot, but that does not stop them from talking about it a whole lot.
Why? Because they cannot figure out that the universe is the way it is. Why is it this way and not some other way? Why don’t we live in a universe with different physical constants or where gravity works differently?
We can certainly find out why some things work the way they do. Chemistry works because atoms work like so. Magnets work because of the magnetic field. And the magnetic field works for this and that reason.
Eventually, we are going to run out of the ability to explain stuff. There is no infinite regress to explanations. We must accept that we have explained everything we can and somethings just are. We might have found the most fundamental existents in nature and how they work. But it would make no sense to ask “why”. Why do they exist? Why don’t we live in a universe where they don’t exist or work differently?
There are no answers to such questions. We just have to accept that some things are and we will never know why.
But the idea of parallel universes is meant to somehow skirt these fundamental limitations by assuming that everything has an alternative. Even the most fundamental aspects of nature.
That is not so. Nor does the idea of postulating arbitrary alternatives to everything help us understand anything. Yes, sometimes considering alternatives can help us gain insight into the way things are, but not always. Many other times this is pointless, especially when those alternatives are impossible and give no insight into how things are.
There is no alternative to existence as such, but that is exactly what the concept of parallel universes alleges! This might be a fun mental exercise but suggesting it as a metaphysical proposition is beyond foolish. It certainly does not explain anything.