Trouble with physics

The theory of everything

I think when you’ve absorbed a lot of material, especially the old material, you get a handle on the theory of everything. The Einstein digital papers are important for this. That’s where you learn how gravity works. You learn that light curves because the speed of light is spatially variable. Not because it follows the curvature of spacetime. You learn that a gravitational field is a place where a space is neither homogeneous nor isotropic in a non-linear fashion. Hence when you plot your metrical measurements…

Continue ReadingThe theory of everything

Even physicists don’t understand quantum mechanics

Check out Sean Carroll’s New York Times article Even Physicists Don’t Understand Quantum Mechanics. I thought it was great. And I just loved that subtitle: Worse, they don’t seem to want to understand it. Carroll started by quoting Feynman, who said this: “I think I can safely say that nobody really understands quantum mechanics”. That’s a good start. Feynman was known as the great explainer, but he couldn’t explain how a magnet works. Or how gravity works. Moreover he was a major contributor to quantum electrodynamics,…

Continue ReadingEven physicists don’t understand quantum mechanics

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…

Continue ReadingMisconceptions in particle physics

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…

Continue ReadingYou can lead a horse to water

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…

Continue ReadingQuantum physics is cargo cult science

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…

Continue ReadingEinstein’s unfinished revolution

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.…

Continue ReadingQuantum computing and the quantum quacks

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…

Continue ReadingQuantum gravity is a castle in the air

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…

Continue ReadingThe information paradox

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…

Continue ReadingThe nuclear disaster