# Beyond the Standard Model (where *are* we going?)

## Main Question or Discussion Point

Alright, so I'm just getting through my first semester of QFT and while I'm not quite ready to step into anything really heavy, I'm close to the point where I can read introductory material on a technical level (like, I could probably start Zweibach's Strings for Undergrads). I've been reading some various physics blogs and while many of the posts are quite old (around the time when Woit and Smolin were publishing their popsci books), I still get the sense that there is some hostility towards strings.

Will starting some of this material help me see where this criticism is coming from? My goal, presently, is to find topics in physics that are new areas that require exploration [yes, I'm being optimistic] and I've heard from one side that string theory hasn't made a whole lot of progress in the decades since it started and from the other that string theory has many areas which are still untouched and is too expansive to have made significant progress. Where can I start looking to answer these questions myself? I would like to be able to [at least pretend to] have a grasp on the arguments for and against various models, from a basic technical standpoint. The idea of falsifiable (or not) has arisen on a few occasions, for example, and I'd like to know exactly why some theories are or are not.

So basically (based on my knowledge-base): where do I get started in terms of books and lectures; which theories should I investigate and is there any particular order I should consider them in?
If I should wait until I have significantly more material under me, that's fine too. I'm not in a hurry; I've got time to think about these things before worrying about a PhD or anything.

## Answers and Replies

Related Beyond the Standard Model News on Phys.org
Well, you can consider yourself lucky because you are starting your career at the time of the LHC. If I were you I would plan on working closely with data and try to get a good grasp on collider phenomenology. On the other hand, if you are interested in more formal BSM stuff, I would not start with a book on string theory but instead I'd recommend going through some literature on supersymmetry first, eg. Steve Martin's "Supersymmetry primer" or even watch Jon Bagger's PITP lectures http://video.ias.edu/pitp-2010 . To get some motivation I'd recommend watching Nima Arkani Hamed's lectures on the same page. Also, you may find other PITP lectures from previous years helpful. TASI summer school lectures are also a good source but you probably want to get done with your QFT class first :)

marcus
Gold Member
Dearly Missed
Elwin, you ask "where are the criticisms coming from"? The most cogent I suppose has come from Phil Anderson, Sheldon Glashow, Gerard 't Hooft, Carlo Rovelli, Richard Woodard, Lawrence Krauss. It would be worth reading carefully some of what they have had to say. They have positive comments about string but also make points that tend not to be stressed in the string literature itself, and which might not occur to you independently.

There is also this special issue of the Foundations of Physics journal called "40 years of string theory". It is edited by 't Hooft and associates---and has articles mostly by string theorists. As an outsider, the editors invited Carlo Rovelli to provide a critical outside perspective. Of course he also has nice things to say about string, and also makes critical points as per request.

Atyy mentioned one or two of the articles in this special issue of the Foundations journal. It is kind of a grand overview retrospective and stock-taking mostly by the string people themselves, but containing some critical reflection.

I expect you can find many of the articles online using arxiv search by specifying search terms like "Forty years of String Theory". If you have any trouble ask for help.
EDIT: So far I find only 6 of the articles online which will be included in the forthcoming issue of Foundantions. There will be many more, but it's still early:
http://arxiv.org/find/grp_physics/1...CT+Forty_Years_of_String_Theory/0/1/0/all/0/1

===================

Personally in your shoes I would also be interested in what physics departmental chairmen see as the most promising lines of HEP theory research, going forward. This is a window http://particle.physics.ucdavis.edu/rumor/doku.php?id=archive:2011 into the minds of a dozen or so departmental chairmen and their hiring committees. Simply by clicking on the names of the 2011 faculty hires (US and Canada) you can see what kind of research these young theoretical physicist new faculty have been doing.

No window is perfect. But it can give you ideas about the lines of theory research that people at various universities currently think are promising and where they want to add to their faculty lineup.

Last edited:
Well, you can consider yourself lucky because you are starting your career at the time of the LHC. If I were you I would plan on working closely with data and try to get a good grasp on collider phenomenology. On the other hand, if you are interested in more formal BSM stuff, I would not start with a book on string theory but instead I'd recommend going through some literature on supersymmetry first, eg. Steve Martin's "Supersymmetry primer" or even watch Jon Bagger's PITP lectures http://video.ias.edu/pitp-2010 . To get some motivation I'd recommend watching Nima Arkani Hamed's lectures on the same page. Also, you may find other PITP lectures from previous years helpful. TASI summer school lectures are also a good source but you probably want to get done with your QFT class first :)
I am applying for the CERN summer program through UMichigan as well as REUs at SLAC, Fermilab, JLab, JPL, and Brookhaven (last I checked). I started the Bagger lectures and felt dumb ._. he went a bit fast for me and I had to pause the video a lot. I was familiar with what he was saying, but I was very unfamiliar with the notation (and this was in the portion ABOUT notation x.x). Hamed's lectures seemed nicer from the little I listened to so far, but I haven't really gotten much time for them yet. I can't find a reliable link to the TASI material, is there anyway you could link me to an archive or something? How would you compare the material to say, PIRSA videos?

Finishing up the QFT course this week, so I should have plenty of free time soon.

I am applying for the CERN summer program through UMichigan as well as REUs at SLAC, Fermilab, JLab, JPL, and Brookhaven (last I checked). I started the Bagger lectures and felt dumb ._. he went a bit fast for me and I had to pause the video a lot. I was familiar with what he was saying, but I was very unfamiliar with the notation (and this was in the portion ABOUT notation x.x). Hamed's lectures seemed nicer from the little I listened to so far, but I haven't really gotten much time for them yet. I can't find a reliable link to the TASI material, is there anyway you could link me to an archive or something? How would you compare the material to say, PIRSA videos?

Finishing up the QFT course this week, so I should have plenty of free time soon.
Here is the link to TASI http://www.colorado.edu/physics/Web/tasi10_annc.html where you can browse the previous years on the left side of the page and click on the Audiovisual Content link if you want to watch some lectures.

I'd say TASI, PITP and PIRSA are all good sources but unfortunately it all really depends on the speakers. If you feel like you are getting lost it may be a good idea to go through some online lecture notes. I'd highly recommend Steve Martin's SUSY primer to start with http://arxiv.org/abs/hep-ph/9709356 .

Shirman's TASI lectures are also pretty decent: http://arxiv.org/abs/0907.0039 and you can also watch them on the TASI 2008 archive.

Various aspects of "Beyond anything such as Standard Model" ?

1. Didactic simplicity
Fifteen years ago, I wrote a 115 page mini-book including math basics, history, all possible calculations of Maxwell-Lorentz electrodynamics, special relativity, Lagrangian-Hamiltonian formulations of electrodynamics etc.. A quite "authoritative" university professor told me that its was as good as Weinberg's or Wheeler's (his words). Later on, I realized that such a small didactic book costing about $2 or 3, eventually sold between$ 5 and \$ 6 interests no editor. This was the end of it, and I abandoned the idea to add quantum fundamentals + general relativity, 50 to70 pages- including all math formalisms (complete, step by step, easy to learn by 16-year old with zero math basis) .
Simplicity also means that physics is above all about observed facts, thus way before theories whose beginning must, in all theories, be integrally based on empirical facts (ALWAYS starting with one fundamental, the problem being which one).

2. Simplicity in Nuclear
These forums should include the possibility to introduce simple equations, this is to say Greek symbols, low and upper indices, because one cannot build physics on ideas only.
However, I will roughly detail here the central nuclear force (old Russian terminology). The first element to evidence is the Yukawa range or distance, without which there is no nuclear (empty theory). One thus writes the centripetal force mv[square]/r = kv[square]/r[n] , giving a determined value for r, that is to say the Yukawa distance characterizing the strong nuclear force. This, in the simplest case, referred to as "electric" in analogy with electromagnetism. Weaker "magnetic" components, referred to as "spin forces", again according to Russian terminology, are calculated subsequently.
This is a rough example of what "beyond standard model" should mean in practical observational terms. With respect to SM, or similar, these are only part of the problem since being dualistic theoretical representations for an observer looking at particles in a laboratory, dual viewpoint similar, if not identical, to initial QED. In a subsequent post, I will show why this process cannot lead to a quantitative formulation of forces. nor a generalization of Schrödinger's equation (I use its scalar wave-function), both elements indispensable for assuring-verifying empirical confirmations without which theories are not, and never will be, science. In other words both types of theories, one dual such as SM, plus another purely local, have to be constructed in parallel fashion. The "local" one giving all interactions plus Schrödinger's equation (example without spinors for energy definition).
These elements here have been published in an international physics journal.