This is Part 1:
Now, it might seem entirely obvious today that you can do geometry in any number of dimensions, but it’s actually a fairly recent development. It wasn’t until eighteen forty-three, that the British mathematician Arthur Cayley wrote about the “Analytical Geometry of (n) Dimensions” where n could be any positive integer. Higher Dimensional Geometry sounds innocent, but it was a big step towards abstract mathematical thinking. It marked the beginning of what is now called “pure mathematics”, that is mathematics pursued for its own sake, and not necessarily because it has an application.
However, abstract mathematical concepts often turn out to be useful for physics. And these higher dimensional geometries came in really handy for physicists because in physics, we usually do not only deal with things that sit in particular places, but with things that also move in particular directions. If you have a particle, for example, then to describe what it does you need both a position and a momentum, where the momentum tells you the direction into which the particle moves. So, actually each particle is described by a vector in a six dimensional space, with three entries for the position and three entries for the momentum. This six-dimensional space is called phase-space.
By dealing with phase-spaces, physicists became quite used to dealing with higher dimensional geometries. And, naturally, they began to wonder if not the *actual space that we live in could have more dimensions. This idea was first pursued by the Finnish physicist Gunnar Nordström, who, in 1914, tried to use a 4th dimension of space to describe gravity. It didn’t work though.
Sabine Hossenfelder, “Does the Universe have higher dimensions? Part 1” at BackRe(Action)
This is Part 2:
As I explained in the previous video, if one adds 7 dimensions of space to our normal three dimensions, then one can describe all of the fundamental forces of nature geometrically. And that sounds like a really promising idea for a unified theory of physics. Indeed, in the early 1980s, the string theorist Edward Witten thought it was intriguing that seven additional dimensions of space is also the maximum for supergravity.
However, that numerical coincidence turned out to not lead anywhere. This geometric construction of fundamental forces which is called Kaluza-Klein theory, suffers from several problems that no one has managed to solved.
One problem is that the radii of these extra dimensions are unstable. So they could grow or shrink away, and that’s not compatible with observation. Another problem is that some of the particles we know come in two different versions, a left handed and a right handed one. And these two version do not behave the same way. This is called chirality. That particles behave this way is an observational fact, but it does not fit with the Kaluza-Klein idea. Witten actually worried about this in his 1981 paper.
Enter string theory. Sabine Hossenfelder, “Does the Universe have higher dimensions? Part 2” at BackRe(Action)
String theory predicted 26 dimensions. Supersymmetry brought it down to ten. You probably get the picture though.
This creates the same problem that people had with Kaluza-Klein theory a century ago: If these dimensions exist, where are they? And string theorists answered the question the same way: We can’t see them, because they are curled up to small radii.
Sabine Hossenfelder, “Does the Universe have higher dimensions? Part 2” at BackRe(Action)
The difference between quantum mechanics and string theory is that quantum mechanics is weird but demonstrable. String theory is weird, period. Gotta be a message in that somewhere.
To understand what a two-dimensional world would be like, try Flatland (1884).
Before we get into higher dimensions, it is first good to note Hossenfelder’s own beliefs in her rejection of a personal God.
She states, in her rejection of a personal God, that “if you believe that evolution does not happen, or that praying cures cancer, and so on. If you want to defend such beliefs, you are in the wrong channel, good bye. I will assume that you are here because, as I, you want to understand what we can learn from nature, so ignoring evidence is not an option.”
Well, as someone who has searched high and low for ANY evidence that unguided material processes, i.e. evolution, can explain the origin, and subsequent diversification, of all life on earth, I certainly take umbrage to her accusation that I, and other ID advocates, have been ignoring the scientific evidence.
In fact, Evolution has many lines of evidence that directly falsify it. Thus Darwinists, contrary to what Hossenfelder believes, are actually the ones who are ‘ignoring evidence’, not ID advocates.
Moreover, as a Christian who has seen a few ‘small’ miracles in my own personal life in answer to prayers, I also certainly take umbrage to her insinuation that prayers are ineffectual.
But anyways, besides all that, I find Sabine Hossenfelder to be very hypocritical in her claim that “ignoring evidence is not an option.”
Sabine Hossenfelder herself was blatantly “ignoring evidence” when see rejected the free will experiment of Zeilinger and company, and instead opted to believe in what is termed ‘superdeterminsim’.
Moreover, (besides Hossenfelder blatantly ignoring scientific evidence when it contradicts her priori philosophical belief in determinism), from. what I can gather, Sabine Hossenfelder also believes, (although she has been a very staunch critic of string theory and supersymmetry), that there still might ultimately be a single overarching mathematical ‘theory of everything’ that will eventually be discovered.
In short, in her very ‘unscientific’ appeal to ‘superdeterminism’, and in her ‘faith’ that there very well might be a single overarching mathematical theory of everything’ that is eventually discovered, (with no need of God to explain its existence), Hossenfelder basically views mathematics as being a rival to God rather than ever being a path to Him.
Hossenfelder’s belief that mathematics is somehow a rival to God rather than being a path to Him is very unfortunate thing for her to believe since the higher dimensional mathematics, that Hossenfelder herself is touching upon in her present videos, unambiguously points us to God.
Specifically, when looking at the higher dimensional mathematics that actually describe this universe, (and ignoring the imaginary higher dimensional mathematics of string theory and supersymmetry which have no experimental support), we find, as Eugene Wigner himself put it that “We now have, in physics, two theories of great power and interest: the theory of quantum phenomena and the theory of relativity.,,, The two theories operate with different mathematical concepts – the four dimensional Riemann space and the infinite dimensional Hilbert space, respectively.”
Specifically, (as to higher dimensional mathematics unambiguously pointing us to God), whereas Atheists have no experimental evidence that their imaginary higher dimensions in string theory and supersymmetry are real, the Christian Theist, on the other hand, can appeal directly to Special Relativity, General Relativity, and Quantum Mechanics, (and the higher dimensional mathematics that undergirds those theories), to support their belief that God upholds this universe in its continual existence, as well as to support their belief in the reality of a heavenly dimension and in a hellish dimension.”
Moreover, if we do not reject the reality of free will, (as Hossenfelder ‘unscientifically’ did in her appeal to superdeterminism), and allow the Agent causality of God ‘back’ into physics, as the Christian founders of modern science originally envisioned,,,, (Isaac Newton, Michael Faraday, James Clerk Maxwell, and Max Planck, to name a few of the Christian founders),,, and as quantum mechanics itself now empirically demands (with the closing of the free will loophole by Anton Zeilinger and company),,,, if we rightly allow the Agent causality of God ‘back’ into physics, then that very reasonable concession provides us with a very plausible resolution for the much sought after ‘theory of everything’ in that Christ’s resurrection from the dead provides an empirically backed reconciliation, (via the Shroud of Turin), between quantum mechanics and general relativity into the much sought after ‘Theory of Everything”. Here are a few posts where I lay out and defend some of the evidence for that claim:
Verse
A word is not a thing. A math formula is not a thing. Multiple dimensions are extremely useful in all sorts of math processes. This doesn’t mean that dimensions are things. All dimensions, not just the ‘extra’ ones, are syntactic forms that we use to help build concepts and products.
The three ‘basic’ dimensions aren’t even neurologically natural. Our internal universe is more like 3d polar coordinates, dominated by angles instead of linear distances. Altitude and azimuth, not length and width and height.