Recent content by bhobba

Gleason's Theorem: https://en.wikipedia.org/wiki/Gleason%27s_theorem Thanks Bill

Poincaré had already discovered a significant amount, so shock isn't the word I would use. Its significance, IMHO, was in showing the world the frightening ease Einstein had with the substance behind the equations, like Feynman and Lev Landau had later, but few others. It ushered in a new...

As explained above, it does fit, but only at low energy scales. In fact, it is suspected that all the so-called Standard Model is like that. Thanks Bill

This is an important point that is often not made clear even in professional literature: https://websites.umass.edu/donoghue/research/quantum-gravity-and-effective-field-theory/ Thanks Bill

Feynman wrote widely about the difference between knowing and understanding. For the first course in calculus-based physics, study the set textbook, take notes in class, do the problems and past exam papers. Thats how I got straight honours in a math degree. However, after getting over that...

Without a doubt, it should not be studied until you have completed the suggested reading list, especially Townsend's A Modern Approach to Quantum Mechanics and Boaz. Also strongly recommended to come to grips with Rigged Hilbert Spaces, Gelfand Triples, etc is a good book that introduces...

The basics of calculus, such as those found in my favourite introductory book (can be studied after US Algebra 2 or Australian Year 9 math): https://www.amazon.com.au/Quick-Calculus-Self-teaching-Manual-Self-instruction/dp/0471827223 Then: To go further, you need more math. I recommend Boaz...

The nature of time is a topic many find interesting. A recent thread about the topic was closed (correctly) as personal speculation. However, articles on the topic have appeared in peer-reviewed journals eg https://journals.aps.org/prl/pdf/10.1103/PhysRevLett.131.140202 I am posting it here...

Got it. Thanks Bill.

Wait a minute, if I remember correctly, EPR concerns that if you measure position or momentum, you can immediately predict the position or momentum of the other particle. This would seem to imply they are now separate particles and not entangled. What am I missing? Of course they were...

The general principle is that in QM the outcome is the eigenvector of the observable. Here it is a product state of 2 separate single particles. This is the collapse of the wavefunction (or quantum field) that lies at the heart of QM. The cause is the interaction with whatever is doing the...

Peter beat me to the punch - he often does o:)o:)o:)o:)o:) Thanks Bill

It's better to think in terms of Quantum Field Theory (QFT) for this one. Entangled particles are a single excitation of the field, so thinking in terms of two separate particles makes no sense. If you think of the quantum field, when one particle is detected, the entanglement is broken, and...

I am a math graduate who self-studied physics. My suggestion is a little bit different. I found the following text a cheap, easy read as a first acquaintance with calculus-based physics: https://www.physics2000.com/ Then, and only after Physics 2000, The Feynman Lectures on Physics...

Well, that depends on what you mean by real. If only philosophers would agree on that, it may be answerable, but since they do not, your guess is as good as mine. Thanks Bill