Trouble with physics

Misconceptions in particle physics

Physics is said to be the king of the sciences, and particle physics is said to be the most important branch of physics. As per the Wikipedia particle physics article, it’s the branch of physics that studies the nature of the particles that constitute matter and radiation. The article tells us that elementary particles are excitations of the quantum fields, and says this: “the currently dominant theory explaining these fundamental particles and fields, along with their dynamics, is called the Standard Model”. Glenn Starkman gives a…

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You can lead a horse to water

I thought I ought to say something about some of the conversations I have with some physicists. A recent example concerned gravity, and why light curves. I found myself talking to a guy doing a PhD called Erik Anson. At the end, I thought of the old adage: you can lead a horse to water, but you can't make him drink. I am reminded of some of the conversations I had years ago with Young Earth Creationists. You can show them the strata, the fossils, and…

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Quantum physics is cargo cult science

Ethan Siegel wrote a blog post this week called This Is Why Quantum Field Theory Is More Fundamental Than Quantum Mechanics. I read it and sighed, because so much of it is misleading. This sort of thing has been in the air recently, because Lee Smolin gave a lecture on Einstein's unfinished revolution. Smolin said quantum mechanics was incomplete, then doubled down and said it was wrong. I think he's right, only more than he knows. So I thought I'd use Siegel's post to show just…

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Einstein’s unfinished revolution

Lee Smolin gave a lecture at the Perimeter Institute this week. Here’s the blurb: “On April 17, in a special webcast talk based on his latest book, Einstein’s Unfinished Revolution, Perimeter’s Lee Smolin will argue that the problems that have bedeviled quantum physics since its inception are unsolved and unsolvable for the simple reason that the theory is incomplete. There is more to quantum physics waiting to be discovered”. This sounds interesting. It's definitely my kind of thing. Let’s take a look. 00:49 Greg Dick starts…

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Quantum computing and the quantum quacks

I have a computer science degree. I work in IT, and have done so for many years. In that period "classical" computers have advanced by leaps and bounds. I remember teletypes and paper tape, and punched cards too. I also remember when a top-notch disk drive was the size of a washing machine and the cost of a car. It provided a miserly 10 megabytes of storage. My disk drive today is the size of my wallet and cost £46.99. It provides a terabyte of storage.…

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Quantum gravity is a castle in the air

When you spend some time digging into the history of physics, you find yourself uncovering the foundations of physics, and then you come to appreciate a few things. You come to appreciate how gravity works, and why an electron falls down. It isn’t because gravitons are flying back and forth: Graviton image by Julie Peasley, see http://www.particlezoo.net/ You also come to appreciate that light interacts with light to form electrons and positrons in gamma-gamma pair production. You come to appreciate that the electron is not a…

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The information paradox

The information paradox was first mooted by Stephen Hawking in 1976. For an introduction to the subject, see Brian Koberlein’s black holes tell no tales or do they? Then see Hawking’s paper on the breakdown of predictability in gravitational collapse. Hawking said information is lost down a black hole because the quantum emission is completely random and uncorrelated. He also said “this means there is no S matrix for the process of black-hole formation and evaporation”. The S-matrix is the scattering matrix which is to do…

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The nuclear disaster

The nuclear force is the force that keeps protons and neutrons together in atomic nuclei. It is often said to be due to a pion exchange proposed by Hideki Yukawa in 1935. His Nobel prize lecture Meson theory in its developments gives some background: “As pointed out by Wigner1, specific nuclear forces between two nucleons, each of which can be either in the neutron state or the proton state, must have a very short range of the order of 10-13 cm, in order to account for…

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The proton

If you look around the internet you can find articles like Matt Strassler’s what's a proton anyway? He says the proton isn’t made up of three quarks joined together by three gluons. He says that’s a lie, a white lie, but a big one. Instead he said there’s “zillions of gluons, antiquarks, and quarks in a proton”, and gives a picture of a whole host of quarks and gluons, all mixed up together like beans in a bag. All “rushing around as fast as possible, at nearly…

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The hole in the heart of quantum electrodynamics

Pair production is the creation of a particle and its antiparticle. Some say it was first observed in 1929, but it's usually accredited to Carl Anderson in 1932. He used a cloud chamber and an electromagnet to investigate cosmic rays. He effectively split a gamma photon over an atomic nucleus to create an electron and an antielectron. He called the latter the positive electron, which was soon shortened to positron: Image from schoolphysics However whilst he realised that he’d discovered the positron, he didn’t realise that he’d performed pair…

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