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Our reading selection for November 2013 is The Particle at the End of the Universe: How the Hunt for the Higgs Boson Leads Us to the Edge of a New World. You may use this thread to post questions, comments, and reviews, at any time.

I already have this book. So I have no excuse not to join November's read!

I just finished reading the book. It's very engaging, as Sean Carroll is an excellent author and a theoretical physicist who knows what he's talking about. The book is very good for the history; I learned a lot about the largest machine ever built--the LHC (Large Hadron Collider) at CERN. The stories about the people who predicted the existence of the Higgs boson, and a few of the people involved with the experiments are very interesting. I found that the theory behind it all to be a bit confusing, and I did not follow some of the logic. Here is my review.

Anybody else reading the book? What do you think?

I'm just about halfway through it. I liked the background chapter on quantum field theory and would like to read more about that sometime. I have also found a couple chapters a bit confusing and I hope I am getting enough of it to appreciate the rest of the book.

David wrote: "I just finished reading the book. It's very engaging, as Sean Carroll is an excellent author and a theoretical physicist who knows what he's talking about. The book is very good for the history; I ..."

Thanks for the excellent review, David! I don't have the book, but I decided not to join this month's group read primarily because of lack of free time. The metaphor with Angelina Jolie reminded me of a similar one in which the Higgs boson is compared to 'a Nobel prize winner' that attracts attention at a party. :)
Well, I'd like to find a clearer explanation why a particle with the energy/mass of the Higgs boson 'attracts attention', unlike bosons with different energy/mass.

Carroll is proficient at explaining complicated information. In spite of my very limited and outdated background in physics, I can understand enough to make the read very worthwhile. It is easy to understand why the Higgs Boson has attracted attention at many parties (as noted by BetseaK)

The most frequent expression in the book seems to be ‘The Nobel Prize��.
Is it a ball game among physicists?:)

I just finished chapter eight. Didn’t understand much.
And all those who already commented admit being confused at least to a degree, too.
Whoohoo! I’m not alone:)
I was thinking, maybe that is the fate of any popular book on theoretical physics without pictures and equations?
Looks like since Newton everybody agrees that the natural language of Nature (pun not intended) is the language of equations (differential equations to boot); well, maybe of mathematics in general. And in most popular books an attempt is made to translate this language into everyday language (the book in discussion I think has only one formula �� E=mc2) �� and make the subject more clear! Seriously? Seems like, simply linguistically, there is some contradiction here.
So what to do? I see only two choices: Grab real deal books on physics and mathematics and study. Does not seem very realistic for most of us for obvious reasons. Or, be satisfied with bits and pieces of distorted knowledge that is somewhat comprehensible. Sad..but seems like true to me.

And I have a question. It seems like a basic fact of physics that I just don’t know. Hopefully, in this group, somebody could help me.

Actually, the question is two-fold. First, Sean Carroll says in chapter eight that the lowest ENERGY STATE of the Higgs field is 246 GeV. Is it the total Higgs field energy in the whole Universe? Apparently not. Is it the energy at any given point of space? Then I don’t understand it. Because then any nonzero volume of space would contain infinite amount of energy of the Higgs field. In other words, as I remember from the time of the First Kingdom, the energy of a field is a function of volume, not point. And GeV IS a dimension of energy, not of energy density (the latter IS a function of point).
Evidently, I don’t understand something here. Or some slang has been used in the book that I am not aware of. Does anybody know what S.C. is talking about?

The other part of the question is even more confusing than the first one. Hope is the confusions are connected and can cancel each other out. This part is due to the writing style in addition to something I don’t know in physics (I think). On the same page S.C says that 246 GeV is actually the value of the Higgs field. Not energy. Because to make the field ZERO, he says, takes extra energy �� much more than 246 GeV. Ah, so the energy and the field value ARE different concepts! Why same number and dimension? I think an author should be more clear when writing for general public..

Particle physics is a new area of reading for me -- I left my formal study of science a half century ago and my graduate work and career were not in science.

It took me an inordinate amount of time to read this book but I enjoyed it. The vocabulary, explanation of the particles and fields, stories of the discoverers including their interpersonal exchanges and disagreements, CERN, the struggle for recognition, and the general politics and quirkiness of the field kept me enthralled. Carroll is on the winning side of that political battle. His discussion seemed careful and respectful.

The GeV was beyond me -- I decided it would not matter if I could not understand it, however, if anyone can explain, it would make my day.

After the message 7. Sean Carroll mentioned that physicists sometimes talk about temperature in terms of eVs (or GeVs), that is �� in terms of energy units. If it is temperature that was implied when he said, ��..the Higgs field sits near 246 GeV rather than near zero..��, then it might make sense, because temperature is defined to have a value at each point in the medium as opposed to energy, the latter being defined for a given volume of space. And I also recall that when they talk about Cosmic Microwave Background Radiation, they talk about its temperature at each point of the Universe.

And that’s my question/problem.

As I recall from the ancient times, I learned and understood the concept of temperature only for the ideal gas. In which case, the temperature is proportional to the concentration of the molecules in the gas and their average kinetic energy. In other words, temperature is how many blows a molecule gets and how hard. If it’s not an ideal gas but some substance made out of molecules, I can understand, it must be something analogous if more complicated. But what is the temperature of a field? Any field. Say �� electric? Say, there is a box of vacuum somewhere (no particles), and within it, there is a uniform electric field E = const. Is there any temperature induced by this field in the box?

I’m sure for somebody in this group such questions are trivial. Can you share an answer?

I enjoy reading the book overall, btw.

Bigollo wrote: "After the message 7. Sean Carroll mentioned that physicists sometimes talk about temperature in terms of eVs (or GeVs), that is �� in terms of energy units. If it is temperature that was implied whe..."

Bigolio, I didn't understand this very well from Carroll's book. However, I found this that does a good job, if you are willing to look at the math.

The equilibrium level of most fields (e.g., electric) is zero, but the equilibrium level of the Higgs field is non-zero (246 GeV). This is not a temperature, but a scalar level that happens to have units of energy.

David wrote: "Bigollo wrote: "After the message 7. Sean Carroll mentioned that physicists sometimes talk about temperature in terms of eVs (or GeVs), that is �� in terms of energy units. If it is temperature that..."

David, thank you so much for taking your time and finding the web. I'll see if I can make time myself and dig into those articles.

David wrote: "Bigollo wrote: "After the message 7. Sean Carroll mentioned that physicists sometimes talk about temperature in terms of eVs (or GeVs), that is �� in terms of energy units. If it is temperature that..."

Thanks for the link to the web site, David! Ehh, I would need someone to explain me those equations�� Nevertheless, it's a bit clearer to me now how the equilibrium energy level of the Higgs field can be non-zero. :)

BetseaK wrote: "Thanks for the link to the web site, David! Ehh, I would need someone to explain me those equations�� Nevertheless, it's a bit clearer to me now how the equilibrium energy level of the Higgs field can be non-zero. :) "

The equations on that web page are for a standard wave equation. I can give you a physical scenario that corresponds to that equation. Suppose you lay a long, frictionless rope on the ground. Move one end of the rope back and forth, so that you create a wave that propagates down the rope to the far end. This creates a wave with a speed "c", which in the case of the Higgs field is the speed of light. If the field is in equilibrium, then raise the whole rope to a certain level, say, 246 GeV (admittedly doesn't make much sense for a macroscale rope).

The left hand side of that equation is, yes, the senior part of the standard wave equation. But the equation as a whole in the article is nonlinear �� the right hand side is a polynomial (in terms of unknown function) of third order. With the analogy that David suggested, the right side of the equation (for a small amplitude oscillating rope) is ZERO (boundary conditions will be a bit funny �� your hand moving back and forth). Life is easy here. The only equilibrium solution of such equation is identical zero.
I would change the analogy slightly. We can consider not transverse waves on the rope, but longitudinal waves along, say, a long spring or elastic string. One end is fixed, and you jerk back and forth the other end along the length of the spring. (Jerks must be gentle). Same wave equation describes the situation. In this case, for the unknown function we can choose the strain in the spring at each point. And the equation again, for ‘normal�� materials and small oscillations will have zero at the right.
Now imagine if for some material, you can stretch the spring to a certain degree (say 246 whatever:), and then still are able to send small oscillations along the spring on top of that strain. The point is that in this case you will have to have a non-zero term at the right hand side of the equation.

In the article, they denote the unknown function of the wave equation - H, and call it the Higgs field. It has energy units. Still confusing. But anyway, to complete our analogy, we may imagine the Higgs field somehow originally strained all over our universe. (Like if our old spring has been strained to a certain degree and held it that way before our other hand pulls and pushes on it). And this constant ‘strain�� of the Higgs is stable. Any oscillations on top of that ‘strain�� ARE Higgs particles.
They say the Higgs field could be zero, but that solution is unstable. (They don’t go to explain why in the article.)

Or it’s all my fantasy. When I don’t understand something I do turn to fantasy:)

To the message 14. Naa. They say any analogy limps. Mine seems to limp on both legs. For that physical interpretation that I suggested, the equation would be still the same �� with zero at the right hand side. If we add some constant strain to the whole spring, the equation does not really change. Maybe the boundary and initial condition will have to be rewritten. I remember a line from some old movie - father admonishes his son, “Think, before you speak!�� That’s how I feel now, using split personality techique:)

Anyways, the wave equation for the Higgs field has this three-fold knot at the right hand side (which is the very beauty of it), with three equilibrium points. And at least one of them �� zero - is unstable.

It would be nice to find a simple down to earth phenomenon that is described by the same equation. That way we would have a model of the Higgs field right on our desk. But that’s for someone who is not very rusty playing with differential equations:).

Bigollo wrote: "To the message 14. Naa. They say any analogy limps. Mine seems to limp on both legs. For that physical interpretation that I suggested, the equation would be still the same �� with zero at the right..."

To the messages 13, 14 & 15. David and Bigollo, many thanks for your time and effort. I'm not a big fan of analogies, either, and it's comforting to see that you both, though much better versed in maths than me, are also confused with the non-zero energy level of the Higgs field.
So,... let me do my bit, for what's it worth, bearing in mind that I'm a language teacher. :)
What I've read on the web site, which David gave the link to, and what Bigollo says in the message 15, reminds me of what I've learned from Records of the Future - Classical Entropy, Memory, and the 'Arrow of Time' about ideal reversible processes. Well, it seems to me that the maths of the Standard Model produces the result according to which the Higgs field overall behaves as an ideal reversible process. So, its overall stable oscillation state is not zero but corresponds to a non-zero energy level. Hmm,... I must admit that this possibility does not seem very likely to me in reality. :(

If you want to understand the subject better, then don't take a peek at this hilarious musical video on Youtube, .

Also, if you like string theory, don't watch this awesome musical video, .

After reading 40% of this book I had to stop. It became too difficult.

The 10% of the book that I felt I was able to understand I loved and found fascinating.

My efforts were thwarted at symmetry.

Thanks for the review/input Daisy! I haven't read it, but have it sort of on my tbr list.

Kenny, I recommend it, even though I struggled a little. It's a great book.

Daisy wrote: "After reading 40% of this book I had to stop. It became too difficult.

The 10% of the book that I felt I was able to understand I loved and found fascinating.

My efforts were thwarted at symmetry."

I'm on that chapter now and it is a tough one! :(

Glynn, Yeah, initially the idea seemed simple and obvious (and good) but it didn't take long before I began to realize that I no longer knew what was going on. lol

Carroll mentions that this insight "that sufficiently powerful symmetries give rise to the forces of nature" is "not an easy one to grasp." And, later goes on to write that "It's not supposed to be simple."

Good luck with the chapter! I hope that it will be easier for you to get through this part.

I'm also currently on Chapter 8 which deals with symmetry and the role of the Higgs. Like others I'm struggling and I've had trouble understanding the concept of symmetry as it applies to particle physics, as distinct to what we understand by symmetry in the world we can see with our eyes. I'm now reading the chapter for a second time having taken time out to read a lecture by the Richard Feynman () which discusses symmetry. Obviously, this is pre-Higgs, and it gets rather mathematical at times, but nevertheless it has helped me to have a better grasp of symmetry so I'm hoping that a second reading of Chapter 8 will prove more fruitful.

Overall, I'm very much enjoying the book and Sean Carroll has a talent for presenting complex ideas in a non-mathematical way. I intend to struggle on to the end.

Incidentally, looking on Sean's website, he has a list of errata for this book which may prove useful to some readers - .

Roger

Roger wrote: time out to read a lecture by the Richard Feynman (...) which discusses symmetry

Thank you for posting this link. I believe I will try the same.

At some point, in many scientific review articles, the author takes the subject matter to a level which is beyond my background. Not always. Yet, I thought chapter 8 was at that point.

I'm looking forward to going back to this book.

I think I'm going to give myself another month to finish reading this book. It's definitely worth it.

Just finished chapter 10. I want to see the documentary "Particle Fever" when it comes to the US:

Whew, that was tough.

“Sometimes, as a professor, the thing to do is to not give up.�� from Sean Carroll, The Particle at the End of the Universe: How the Hunt for the Higgs Boson Leads Us to the Edge of a New World

Sometimes this is true for readers too. I’m glad I kept reading this book even though it was difficult.

Funny, just as I got toward the end of the book I thought I felt some dark matter passing though me. (Kidding.)

At least it passed. :) :) :)

Funny.

Happy New Year!