Saturday 15 February 2014

One More Try

My blogging juices have been drying up for some time now, and at this point Résonaances is close to withering. This could be expected. The glorious year 2012 with all the excitement of the Higgs boson discovery was inevitably followed by post-coital depression, only amplified  by the shutdown of the LHC for repairs.

One problem with blogging these days is that, in the short run, things are expected to get worse rather than better. The year 2013 was depressing but at least we could not complain of the lack of action. The LHC was flooding us with new results based on the data collected in the first run. On the Higgs front, the 125 GeV particle discovered the year before was established, beyond reasonable doubt, as a Higgs boson related to electroweak symmetry breaking. The CMB results from the Planck experiment were a sweeping victory for the Lambda-CDM description of  the universe at large scales. The LUX experiment provided the best limits so far on the WIMP-nucleon cross section and slashed the hope that we may be on the verge of detecting dark matter. Plus a cherry on the top: ACME limits on electron's electric dipole moment increased the strain on any extension of the Standard Model with new particles at the TeV scale. Yes, a lot to remember, not much to cherish...

And what about 2014? Are there any results to be released this year that could be at least marginally exciting for particle physicists? I don't see much, and the opinion polls that I have conducted are not optimistic either. Basically, we just expect more of the same: the LHC, Planck, ICECUBE, AMS-02, Fermi... Of course, there is always a non-zero probability that some new results from these experiments will turn out to be a smoking gun for new physics, but the later in the game the dimmer the chances are. The only qualitatively new piece of data among those will be the Planck polarization data, but even that is unlikely to be a game-changer. One may also keep an eye on lightweight contenders: small precision experiments that pursue indirect limits on new physics. Recently there's been new such limits on non-standard interactions between electrons and quarks  from JLab's PVDIS Collaboration who study  low-energy scattering of electrons on nuclei. A similar experiment in JLab called Q-weak promises new results and improved limits this year. If there's anything else like that in the queue I'll be glad if you let me know in the comments section.

So how to live? How to blog? How to make it till 2015 when the sky is supposed to get brighter? I have no idea but I'll try to go on for a little longer. Back soon.

31 comments:

Alex said...

Any hope for neutrinoless double beta decay being observed in 2014?

Bohmian Rhapsody said...

Mama, just killed a blog...

Anonymous said...

When do we expect news from KATRIN?

Jester said...

There are many experiments pursuing 0ν2β decay. Gerda, Exo, Kamland-Zen released new data quite recently, while Cuore, NEXT-100, and SNO+ are under construction. I'm not aware that anything is coming up this year.

cb said...

Post Higgs year and post Valentine day sad physicists?
Why, because low-scale Susy stood LHC8 up?
Well, beauty could be disguised in non standard ways... Why not looking for some Spectral afterlife in a better Space with few natural Scalars instead of many Sparticles?

Luboš Motl said...

Dear Adam, the best way for you to enjoy 2014 is to be saving and collecting those $10,000 that you will perhaps pay me almost as soon as the 2015 LHC run will be launched.

I have prepared and reserved those $100 for you, so you may be looking for those, too. When the bulk of papers with more than 30/fb of LHC data is published with no new physics, you will be this richer. That's a reason to live. ;-)

Jester said...

right, that will certainly make my day, or even week. But that's 2015, the problem is here and now :)

Xezlec said...

What about Muon g-2? It's not 2014, so it doesn't address your immediate concerns, but long-term-wise, doesn't the >3-sigma anomaly in the g-2 measurement seem like cause for hope?

Vladimir Kalitvianski said...

People lived in much harder times, do not forget it.

Joseph Conlon said...

Your CMB section is a bit thin. There are the other polarisation experiments (eg SPTPol) which have data and should be expected to release it this year (and are also at smaller scales way more sensitive than Planck).

Personally I am watching Neff very closely, there are currently 2 independent 2-sigma hints (CMB + H0, and BBN abundances), and the error bars are projected to drop by a factor of ten over the next decade.

Alex said...

I suppose ACME could release something new, but it probably wouldn't be a profound improvement, just "We have vetted this possible source of systematic error and narrowed our error bars a bit." Increasing the confidence in the results is good, but it's nothing that would drastically change the amount of parameter space ruled out (nor would small refinements of the experiment be likely to switch from a null result to a 5-sigma finding of BSM physics).

It will be a few more years, but I'll be curious to see if the axion hunts turn anything up. Axions get less attention than WIMPs, but they're an interesting idea.

Also, not that it matters, but I'm not a particle physicist, just an optical biophysicist who follows particle physics results as a hobby. Some people check sports scores, I check arXiv to see if anything new has been found about the basic constituents of the universe.

Robert L. Oldershaw said...


As a reasonable thing to do while waiting for empirical developments, one might consider the following.

List the major assumptions of fundamental physics and then ask which ones are empirically well-grounded and which ones are taken largely on faith.

Then sincerely explore the potential benefits of changing the poorly tested assumptions.

That paid off handsomely for Einstein, i.e., questioning absolute space, absolute time, absolute simultaneity, the absolutely unshakable Newtonian theory of gravitation, action-at-a-distance, etc.

I might suggest that a good place to start would be with the inadequately tested assumptions of absolute scale and strict reductionism.

Jester said...

Xezlec, true, g-2 may be the smoking gun one day, but it'll take about 5 years to sort it out (the new Fermilab g-2 experiment will start taking data only in 2016)

Jester said...

Thx Joe, I need to study in more detail what will be done regarding the CMB polarization, apart from Planck.

Marc Sher said...

One bit of news in 2014 will be LUX. The data presented last year, which gave much tighter bounds than ever before, was based on less than 3 months of running. By the end of the year, there will be more than 5 times as much data, covering much more of the WIMP parameter-space.

Jester said...

The web page of LUX says the next data release is only in 2015 :(
http://lux.brown.edu/LUX_dark_matter/Experiment.html

Anonymous said...

Well, at least you will have time to listen to Heligoland...

Thanks for the work my friend.

Jester said...

@ comment #3. It seems KATRIN is many years into the future, they will start tritium data taking only in 2015

Anonymous said...

In 2014 a better bound (small improvement to d_n ~ 1 x 10^-26 ecm) or discovery of neutron EDM is expected by the group that published http://arxiv.org/abs/1310.5588 .... Am hoping for the discovery.

Ravi

Anonymous said...

Dont' Die little Jester. Think of all those string theorists who rely on you for some connection to experiment!

VML said...

Hi Adam,

I think your blog is very useful to those that work in Pheno. Have you considered to take some interesting papers from the arXiv and comment them? I mean, apart from commenting experimental results. Probably this will provide a dynamical view of your blog...

Jester said...

You mean comment on Interesting theory papers? That's even more rare than experimental ones ;)

Jester said...

Anon, that's right, the EDM experiments are one thing to keep us alive. Glad to know there'll be an update from ILL.

Alex said...

About dark matter experiments:

I understand that one motivation for the interest in WIMPs as opposed to other dark matter candidates (e.g. axions, sterile neutrinos) is that for plausible WIMP parameters they would naturally be produced with roughly the right abundance in the early universe, i.e. the "WIMP miracle." How close are the experiments to ruling out the regions of parameter space that make the "WIMP miracle" idea compelling?

Anonymous125GeV said...

So here you are once more, in the playground of the broken hearts.
One more experiment, one more entry in a physics blog, self-penned.

Thank you for your blogging. In lack of more interesting alternatives, I wouldn't mind reading semi-boring "Yet another SM confirmation" blog entries every now and then. Except for neutrino-related results, I do not expect nature to give us anything else in the next decade anyway. Congratulations in advance for winning the bet against Luboš.

Barak Kol said...

Thank you for your clear, interesting and intelligent posts.
The world is full of fascination within particle physics and outside of it.

Jester said...

Alex, some particular WIMP scenarios are already excluded. WIMPs interacting with us via Z exchange was excluded back in the 80s by early direct detection experiments. Now we are in the process of excluding WIMPs interacting with us via Higgs exchange. But the WIMP paradigm has enough freedom that experiments will never close the parameter space.
That I don't find the WIMP miracle compelling anymore is another story :)

Tienzen said...

"Basically, we just expect more of the same: the LHC, Planck, ICECUBE, AMS-02, Fermi... "

Why is your eyes which can only see those institution works? There are a lot of works done by individuals.

Anonymous said...

There's loads of really interesting things coming up Jester. Don't lose heart.

Shantanu said...

Jester or anyone else,
would be interested to hear your comments/opinions on Fig 1 of 1401.1146.
That has got to be telling us something beyond canonical Lambda CDM and its not predicted by any simulations?

shantanu

andrew said...

What is the deal with parton distribution functions?

Lots and lots of lots of experimental work is done on them, but I have only the dimmest idea of what they are and nobody ever seems to announce any breakthroughs in that area.