Matt Strassler's excellent QM series

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But what does it really mean?

The physicist Matt Strassler is currently writing a series of excellent articles about how to think about quantum mechanics, focused on the double-slit experiment as his working example. Richard Feynman said that all the mystery of QM was encompassed in this one simple experiment.

If you are curious as to how to think about the wavefunction, and what it really means and how it couples to 'reality', this is the series for you.

Additionally, if you want a little more maths: the benefit exceeds the cost.

What is an Electron Really?

From ChatGPT

This summary, the result of a little prompt-dialogue between ChatGPT and myself, seems as good an account as any other, and is consistent with Matt Strassler's book, "Waves in an Impossible Sea" .

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In the realm of classical physics, an electron is often conceived as a tiny, negatively charged particle orbiting the nucleus of an atom. However, modern physics, particularly Quantum Field Theory (QFT), offers a radically different perspective.

In QFT, an electron is not a point-like particle but rather a quantum excitation of an underlying entity known as the electron field. This field pervades all of space, and what we perceive as an electron is simply a localized disturbance or excitation within this field. This excitation carries certain properties—such as charge, spin, and mass—that we associate with the electron.

The electron's position is not definite until it is measured. Instead, the electron exists in a superposition of possible states, each corresponding to a different location. This superposition means that the electron doesn’t have a single, well-defined position but rather a range of probabilities (quantum amplitudes really) of being found in various locations.

When we incorporate the Many-Worlds Interpretation (MWI) of quantum mechanics, this notion takes on an even more intriguing aspect. According to the MWI, each possible position of the electron corresponds to a different “world” or branch of reality. 

In one world, the electron might be detected at a particular point, while in another world, it appears somewhere else. These different worlds coexist in a vast multiverse which constitutes reality, and the electron’s delocalization can be understood as it existing in multiple worlds simultaneously, with each world realizing a different outcome of its position. Note that in each specific world, the electron is still an 'excitation of the electron field', a 'wavicle' according to Strassler.

This is a difficult ontology to imagine or believe, but it's the best we can do today.

Notebook: Higgs, Gym, Beta-level Simulation

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Higgs field/boson popular science book

I recently read Matt Strassler's book, "Waves in an Impossible Sea" which aims to explain the Higgs field and Higgs boson to non-physicists. It's probably as good as you can expect for such a book. Strassler is a clear writer and doesn't shy away from difficult questions.

For example, he tackles the question of whether light, which travels through a vacuum, needs a (very strange, 'impossible') medium to carry the electromagnetic field. He makes a clear distinction between a medium and a field which is crucial here.

The explanation of the Higgs field "stiffening" quantum fields for particles with mass isn't perfect, but it's perhaps the best analogy available. It encouraged me to revisit the maths - I have some books which are gentler than this.

Exercise Routine

This morning at the gym I continued my aerobic workout: five minutes on the exercise bike, then the stepper, and finally, the treadmill. My goal is to improve my fitness, especially after a bad case of what was likely COVID last June. The breathlessness lingers, but I believe exercise can help. The idea is to use the gym for 15-20 minutes of high-intensity aerobic exercise, complementing my Tai Chi sword form, Tai Chi form and Heian kata (shotokan karate) practice.

With summer approaching I can move some of the latter exercises outdoors, freeing up gym time for equipment-based aerobic work.

Your very own beta-level simulation

An article in The Times recently discussed the use of large language models to create "Grief-Bots" or "Dead-bots" – terms that could use some marketing work! The concept involves feeding a large language model with information about a deceased person, including appearance, voice recordings, conversation samples, and even their style of communication. The system then essentially "reincarnates" the departed, allowing a simulated interaction with a spouse, parent, or other loved one.

One suggestion was to leave such a "beta-level simulation" (as Alastair Reynolds termed it) for your descendants. This could be an alternative to traditional ‘letters cast into the future’, which naturally lack context and specificity.

However, the question arises: what's the purpose of such a simulation? It wouldn't be an information source, as better systems exist and will continue to develop. It wouldn't be the first choice for advice either.

Perhaps it's for emotional support – someone who responds in a way that resembles a spouse, grandparent, or ancestor, acting more like a friend than a resource. Science fiction often explores this theme, sometimes with a Far-Eastern cultural context: ancestor-worship.

While I understand the concept, I suspect most people wouldn't be interested in frequent interaction with such an "archaic entity" when daily life offers so much.

Practically, leaving an operational large language model to your descendants is impossible. Technology advances rapidly, rendering the software outdated and unusable within a year.

A better solution might be to leave training data – biographies, transcripts, and other relevant information. This way, future generations could train a model using the latest software, essentially "reincarnating" you or anyone else.

Forward-thinking individuals might consider this approach for the future. Or perhaps they’ll wonder why on earth they should bother: one’s sprawling digital estate will have all the data any future AI system could ever require, whether you like it or not.

LinkedIn: greedy, evil or just plain stupid?

Prof. Matt Strassler writes: (my emphasis)

I use LinkedIn sparingly, though I have found it beneficial on occasion. But one of its features is that its software is constantly asking you if you want to make LinkedIn-contact with people whom it thinks you might know. That’s understandable; LinkedIn has to make money, and information and contacts are money for them.

But there’s one LinkedIn request that you have to be careful with, in which they ask for permission to import your contacts lists and send LinkedIn invitations to make contact with every single person on that list. 

I don’t have to explain to you why this would typically be undesirable… it’s obvious. Just think of one person you’d rather not talk to, or who’d rather not hear from you, who might be down in a forgotten corner of your list of contacts.

In the old days, if you were to plan something so drastic as contacting hundreds of unrelated people on a single day about joining your professional network, you’d be discussing it on the phone or at a desk with a company representative, having a conversation. And you’d probably have to sign a piece of paper. Moreover, you’d have at least a few minutes, if not days, to consider what you’d done and change your mind.

In the modern age ... clicking is enough. But everyone knows that it is easy to misread something and click on it, or do something through accidental clicking of a touch-pad, a slip of a mouse, or a bump of a touchscreen. I don’t know which of these happened to me yesterday. In any case, in order to take an action as outlandish and irrevocable as sending blanket faux-personalized email invitations to everyone I have ever known, it is essential for a company to have a warning pop-up: “This action will send email invitations to 452 individuals. Are you sure you want to do this?” The default should be “No“, and you have to click on “Yes” for the action to go ahead.

But for LinkedIn, as I discovered yesterday, a single click is apparently all it takes, with no warning screen.  In my opinion, this is somewhere between unethical, negligent, and sneaky.

Actually let’s just call it evil.

I guess like most people on LinkedIn, I've also almost been a victim of this scam. My email-contacts list has more than a thousand entries, based on years of working in high-tech companies and as a technology consultant. I read about Prof. Strassler's disaster and thought, 'There but for the grace of God' ...

Now that I'm out of that, I think LinkedIn is just too high-risk. Goodbye, guys - you brought it on yourselves.