Ether is back! Well, somewhat. Now it's in the form of Higgs field. Unlike ether, Higgs field does not interact with uniformly moving particles, only those that are accelerating. Here's a great book I just recently listened: http://www.amazon.com/The-Black-Hole-War-Mechanics/dp/031601... It's by Leonard Susskind from Stanford. The thoughts experiments in the book are just terrific. Loved it.
An Introduction to Quantum Field Theory
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Re: An Introduction to Quantum Field Theory
#22Earlier quoted context omitted.
The way I've understood it is, particles are localized excitations of fields. You know of the Higgs boson. It is the excitation of the Higgs field, which exists through all space. Similarly, an electron is an excitation of the electron field (not electromagnetic field), which exists through all space. Every single electron is a localized excitation of the same, single field. I don't know how to answer the relativisti…
I understand that, but is it just a neat mathematical model to treat particles as excitations of fields because it makes calculations especially easy or is there really a field out there?
Re: An Introduction to Quantum Field Theory
#23Re: An Introduction to Quantum Field Theory
#24Re: An Introduction to Quantum Field Theory
#25Earlier quoted context omitted.
Compare it with temperature. If you run next to fast atom and you touch it, it doesn't actually feel hot. So temperature is not really a fundamental thing in nature but a higher level abstraction of the different moments of a large collection of particles. Temperature also becomes meaningless and the whole concept breaks down if you have only one or a few particles. It is of course a useful concept nonetheless. So I…
AFAIK the particles vs fields discussion is not the same as temperature vs fields. At the risk of straying into quantum info territory: - given all possible information about a collection of particles, you could compute the temperature. However, knowing the temperature doesn't allow you to determine info about particles uniquely (you can write down a density matrix, and not assign a pure state). - the above doesn't h…
Re: An Introduction to Quantum Field Theory
#26Are quantum fields actual elements of reality or just a convenient mathematical tool to deal with many particle systems? One of the questions I am struggling to find a satisfying answer for for quite some time. Depends on whom you ask? We can't tell because both ways of thinking are completely equivalent? Fields are real! No, they are just a tool! Are there issues with real fields forming a preferred reference frame?…
Re: An Introduction to Quantum Field Theory
#27Are quantum fields actual elements of reality or just a convenient mathematical tool to deal with many particle systems? One of the questions I am struggling to find a satisfying answer for for quite some time. Depends on whom you ask? We can't tell because both ways of thinking are completely equivalent? Fields are real! No, they are just a tool! Are there issues with real fields forming a preferred reference frame?…
Quantum Field Theory is really just ordinary Quantum Mechanics. It is necessary to use fields instead of "wave equations" because the number of particles can vary when the energy of a system exceeds a certain threshhold. (e.g. a single photon having an energy equal to or higher than the E=mc^2 energy of two electrons can transmute into an electron-positron pair. 1 particle transforms into 2. This is very common in hi…
Re: An Introduction to Quantum Field Theory
#28Are quantum fields actual elements of reality or just a convenient mathematical tool to deal with many particle systems? One of the questions I am struggling to find a satisfying answer for for quite some time. Depends on whom you ask? We can't tell because both ways of thinking are completely equivalent? Fields are real! No, they are just a tool! Are there issues with real fields forming a preferred reference frame?…
Can you define what you mean by an 'actual element of reality'?
Re: An Introduction to Quantum Field Theory
#29Ether is back! Well, somewhat. Now it's in the form of Higgs field. Unlike ether, Higgs field does not interact with uniformly moving particles, only those that are accelerating. Here's a great book I just recently listened: http://www.amazon.com/The-Black-Hole-War-Mechanics/dp/031601... It's by Leonard Susskind from Stanford. The thoughts experiments in the book are just terrific. Loved it.
Re: An Introduction to Quantum Field Theory
#30This is a pretty good introduction. I highly recommend Feynman's book "QED: The Strange Theory of Light and Matter" as an excellent in-depth work that does not sacrifice accuracy for the sake of making difficult ideas understandable. It is both very clear to the layperson and accurate to the physics.
I wish I could write like that.