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LHC Restarts High-Energy Quest For Exotic Physics
astroengine writes: It's official: After a long 27 month hiatus for upgrades and a 2 month restart, the world's largest particle accelerator is back in the particle collision business. As of 10:40 a.m. CET (5:40 a.m. ET), the Large Hadron Collider (LHC) was running at record-breaking energies and collecting science data. Physicists now expect the particle collider to run non-stop for the next 3 years. We are in a new era of high-energy particle physics where, for the first time, we don't exactly know what we'll find. "With the LHC back in the collision-production mode, we celebrate the end of two months of beam commissioning," said CERN Director of Accelerators and Technology Frédérick Bordry in a press release. "It is a great accomplishment and a rewarding moment for all of the teams involved in the work performed during the long shutdown of the LHC, in the powering tests and in the beam commissioning process. All these people have dedicated so much of their time to making this happen."
Apparently it will collect 15 petabytes a year.
http://www.lhc-closer.es/1/3/1...
Here is a picture of server room
http://home.web.cern.ch/about/...
love is just extroverted narcissism
https://op-webtools.web.cern.c...
Live on the web -- this is a summary page, with much more available
GR and QFT work very well together in the low energy limit, which goes right to -- and even through -- the event horizons of black holes.
However, the most prominent pairing of GR an QFT -- semiclassical gravity -- cannot deal with arbitrary high numbers of loops. On the other hand, Wilson's EFT work showed very clearly that you do not need to consider arbitrary numbers of loops to have an effective field theory.
The nature of the mathematical device that can probe beyond the UV limit of semiclassical gravity (or how far beyond it can probe) is not yet known, but there is no reason to outright abandon either GR or QFT in practice today, and indeed, there is no clearly better replacement.
Neither GR nor QFT is necessarily *wrong*, but both are incomplete, and the paths to complete one or the other tend to create calculational problems or outright conflicts. It is possible that one may complete to some much higher energy limit (or perhaps to arbitrary energies) while the other does not, which would lead to new problems involving how the metric is generated or how particles with wavelengths comparable to nearby curvature behave, rather than the problems we have currently.
There *is* a desire to have a quantum mechanical description of gravity, simply because every other fundamental field has quantized. However, not every fundamental field nor its internal symmetries nor intereactions has been discovered yet -- that's been a good chunk of the focus at LHC. Moreover, equating QFT with the Standard Model itself is problematical on its own (ignoring gravity), since for example there is no theoretical explanation in the Standard Model itself for the striking similarity (but for a change in sign) in the charge of the electron and that of the proton. It also has even less to say about the Dark Sector, where at least GR has some successful phenomenology and some useful ideas about how to generate metrics sourced by e.g. dark matter. It also has an increasingly large number of finely tuned (but free) parameters with practically no ideas about why they take on the values in our universe. Several successful GR models (including the standard cosmology) have approximately one free parameter and hints about selection mechanisms (although those tend to really put the infinity into an infinitely large universe).
The frustrating thing is that as purely local theories (testable in the scale of devices in laboratories here on earth), both GR and the Standard Model are exquisitely accurate. The LHC, if we're lucky, will show that the SM is clearly incomplete at laboratory device scale, and if we're verrrry lucky will kill off lots of ideas about ways to complete TSM to unification (or even higher) energies, or ways to replace both it and GR in their respective high energy limits (but that's perhaps the least likely outcome, in spite of lots of string/brane theorists' hopes).