# Can string theory make predictions for particle physics?

1. Nov 1, 2006

### CarlB

I attended a string theory lecture this afternoon at the Joint Particle Physics 2006 meeting in Hawaii. One of the string theory parallel lectures caught my eye:

Can string theory make predictions for particle physics?
Washington Taylor, MIT
The appearance in string theory of a wide range of solutions corresponding to low-energy field theories with different gauge groups and matter content poses a challenge to string theorists who wish to make predictions for particle physics. This talk presents a summary of the state of our knowledge regarding the space of string vacua, and describes recent work in which the gauge groups and generation numbers of a set of quasi-realistic intersecting brane models are systematically analyzed.
http://www.phys.hawaii.edu/indico/contributionDisplay.py?contribId=96&amp;sessionId=168&amp;confId=3

He made the point that early estimates that the number of vacua were about $$10^{600}$$ are probably very deep underestimates. He proposed a "Moore's Law" for the landscape, implying that the number of vacua were going to keep increasing indefinitely.

Despite this, Dr. Taylor expressed hope that there would eventually be a prediction come out of string theory. His idea was that there would pop up correlations between various parameters of the standard model. However, in his own explorations which counted how many vacua would have SU(3)xSU(2)xU(1) and 3 generations in a tiny corner of the landscape, he had found that there were no correlations. He was asked about this in the question and answer session and said that he still had hopes because he hadn't looked at all the other parameters of the standard model such as the masses of the particles. (Should have attended my lecture, I guess.)

The lecture was well attended with about 150 people, standing room only.

Carl

2. Nov 1, 2006

### Kea

ROTFLOL :rofl: :rofl:

3. Nov 1, 2006

### CarlB

More color from the string theory talk:

After the talk, one of the questioners started out her query with "I noticed that you avoided using the "A" word ..."

Of course my mind leapt to the possibilities. Antimatter? Axion? Anomaly? Asymmetry? Atheism? Astronomy? Angular momentum? Algebra? Accuracy? Adultery? Ab initio? Aardvark?

Apparently the locals knew what was being talked about and the author, dared by the questioner, used the word "anthropic" in his response. I guess that that's a bit of a dirty word among the stringers.

Carl

4. Nov 2, 2006