David Gross: The Last Five Minutes

[marcus]

David Gross gave a half-hour talk at the Madrid Strings conference of which the last five minutes is a frank expression of personal views.
The video is here, I wish you could drag the time button over until you are at minute 25:00, where he starts saying some things especially on his mind
at close of conference.
http://strings07.blogspot.com/

to get directly to the video of the Gross talk:
http://strings07.blogspot.com/2007/06/demo-distribution-tv-channel-for_3923.html

 

[arivero]

Problem is, probably he reserved some effort for the public conference next day in the center of Madrid. The organization of Saturday event has promised they will email us (the crowd outside) when/if a video become available. The room was crowded already one hour before schedule.

 

[marcus]

I was pretty surprised by how frank and pessimistic Gross was in the last 5 minutes of his talk at the end of Strings '07.

Peter Woit apparently was similarly impressed, and he took the trouble to summarize what Gross says in the online video:

==quote==
After the summary, he gave his own take on the state of string theory, saying that one had to be honest about the lack of falsifiable predictions and that now he had a slide headed “The Failures of String Theory”. He continues to feel that the main failure is because we “don’t know what string theory is”, that something is missing, some principle that would pick out not a “vacuum” but a “cosmology”, one perhaps using new ideas about what space and time are. He said he was not too upset by the landscape, because “we don’t know what the rules are” in string theory, so one can’t argue that string theory implies the landscape. He appeared to feel that he is losing the debate, complaining that this used to also be the opinion of his colleagues, but that they were going over to the other side because of the cosmological constant, saying that if another explanation of the CC was found 90% of the anthropicists would come back to his side. He tried to minimize the size of the CC problem, measuring it with respect to a supposed 1 TeV SSYM breaking scale and working in energy, not energy density units, so it is only too small by a factor 10^16. He compared this to Dirac’s famous large number problem (which Dirac tried to solve not anthropically, but by time-varying constants, leading to a prediction that was falsified), which was finally “explained” by asymptotic freedom. His message to the anthropocists was “just because you don’t know an explanation doesn’t mean it doesn’t exist”.

Finally he mentioned that Strings 08 will be at CERN, Strings 09 in Rome, and no one has yet agreed to host Strings 10. He argued that the series of Strings conferences “must go on”, because they are “like the canary in the coal mine”, and if they stop that would be a very bad sign for string theory.
==endquote==
http://www.math.columbia.edu/~woit/wordpress/?p=572

 

[marcus]

I was wondering how to give some objective, quantitative substance to flesh out what David Gross was saying. Why would he grimly speak of a canary in a coalmine?

One thing is the dropoff in citations. Before 2002 it used to be that each year there would be 12-20 RECENT (last five years) string papers that would be cited as references 100+ times that year in the literature.

But in 2005 and 2006 it was down to 2 or 3 such highly cited recent papers.

This is a dangerous drop in the QUALITY of recent research, as quality is usually measured by tenure committees and anybody who wants quantitative ranks of research value. What it says is the string theorists themselves no longer find the recent work of their colleagues so significant or fruitfull for further work.

We have had several PF threads marking this abrupt decline in citations.
=========

Another indicator is just the decline in raw quantity of published research, which has been far less abrupt.

By doing the same database search, with the same keywords, in successive years one gets an index of the rate of string research publication.
Authors of physics books and journal papers normally provide a short abstract summary containing keywords that indicate what the work is about. Keywords that work well to find String papers are {superstring, M-theory, brane, heterotic, AdS/CFT}. Harvard has a database with the abstracts of research publications in physics and related fields, which we can use to gauge string research publication rates.

The figures for 2002 and 2006 were 1148 and 972. That many published books and articles showing one or more of those keywords in the abstract. We won't know the 2007 figure until the year is over.

2002: http://adsabs.harvard.edu/cgi-bin/n...txt_wgt=YES&ttl_sco=YES&txt_sco=YES&version=1

2006: http://adsabs.harvard.edu/cgi-bin/n...txt_wgt=YES&ttl_sco=YES&txt_sco=YES&version=1

2007: http://adsabs.harvard.edu/cgi-bin/n...txt_wgt=YES&ttl_sco=YES&txt_sco=YES&version=1

=======

Here are data the first six months of each year, same years and keywords. Currently these links give 654, 571, and 435 (stragglers might bring the last figure up to 465 during the month of July, or so, I expect.)

2002: http://adsabs.harvard.edu/cgi-bin/n...txt_wgt=YES&ttl_sco=YES&txt_sco=YES&version=1

2006: http://adsabs.harvard.edu/cgi-bin/n...txt_wgt=YES&ttl_sco=YES&txt_sco=YES&version=1

2007: http://adsabs.harvard.edu/cgi-bin/n...txt_wgt=YES&ttl_sco=YES&txt_sco=YES&version=1

The decline from 2006 to 2007 seems to be more rapid than the annual decline over the years 2002-2006. This could be one of the canaries that David Gross is worried about.

Although I would agree that one can only speculate as to what would have caused him to speak as he did, at the final sum-it-up talk of the conference.

 

[marcus]

In line with the links given in the previous post, here are data for the first seven months of each of three years:

2002: http://adsabs.harvard.edu/cgi-bin/n...txt_wgt=YES&ttl_sco=YES&txt_sco=YES&version=1

2006: http://adsabs.harvard.edu/cgi-bin/n...txt_wgt=YES&ttl_sco=YES&txt_sco=YES&version=1

2007: http://adsabs.harvard.edu/cgi-bin/n...txt_wgt=YES&ttl_sco=YES&txt_sco=YES&version=1

Same keywords (superstring, brane, M-theory, heterotic, AdS/CFT)
Same pattern (stragglers may still bring the 2007 figure up).

2002: 733
2006: 621
2007: 511

To track string citations, going forward, I decided that in each year I would look at the eight recent (published in past five) papers, which garnered the most citations that year, and average up the counts.
Taking 2006 as example this means to look at these two lists:
http://www.slac.stanford.edu/spires/topcites/2006/eprints/to_hep-th_annual.shtml
http://www.slac.stanford.edu/spires/topcites/2006/eprints/to_hep-ph_annual.shtml
and from them pick the top eight string papers published in 2002-2006.
These turn out to AVERAGE 119 cites per paper.
the top eight list for 2006, in case anyone is curious, was
hepth 0301240 226 cites
hepth 0105097 171
hepth 0202021 143
hepth 0106048 109
hepph 0106245 74
hepph 0105249 73
hepph 0106219 72
hepph 0012100 64

according to my notes, lead authors respectively were: Kachru, Giddings, Berenstein, Douglas, Savas, Nima, Giddings, Appelquist
================

If I've done it right, doing this for each of several years gives
year average cites for top eight
2002: 357
2003: 243
2004: 145
2005: 117
2006: 119
This particular index would look like a turnaround, or else a tendency to stabilize at a lower level from the pre-2003 days.

 

[marcus]

the paperback Smolin, orange edition, has replaced the hardcover blue on the physics bestseller list
https://www.amazon.com/dp/061891868X/?tag=pfamazon01-20

as of 7AM Pacific this Sunday morning (26 August) it stood #8 on the physics list with a storewide salesrank of 2156

https://www.amazon.com/dp/061891868X/?tag=pfamazon01-20

For comparison, the five most popular string books had average salesrank 8836
(these being: fabric, elegant, warped, endless universe, and fabric hardcover.)

as of 10AM it stood #4 on physics list with storewide rank of 962
and for comparison the five most popular string books averaged 4568
(these being fabric, warped, elegant, endless, and vilenkin many worlds)

as of 2 PM it stood at #3 in physics bestsellers, with storewide rank of 825

 

[CERDES]

Ultimately, there is an answer or there exist answers. Can we ascertain them at our developmental level to date? I believe we can understand whatever there is to be found but can we determine it without it being handed to us? I remain hopeful.

Best
Frustrated Physicist in Behavioral Sciences