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Scientists To Hunt For Supersymmetric Particle In LHC
An anonymous reader notes this article about the upcoming restart of the LHC. "A senior researcher at the Large Hadron Collider says a new particle could be detected this year that is even more exciting than the Higgs boson. The accelerator is due to come back online in March after an upgrade that has given it a big boost in energy. This could force the first so-called supersymmetric particle to appear in the machine, with the most likely candidate being the gluino. Its detection would give scientists direct pointers to "dark matter". And that would be a big opening into some of the remaining mysteries of the universe. 'It could be as early as this year. Summer may be a bit hard but late summer maybe, if we're really lucky,' said Prof Beate Heinemann, who is a spokeswoman for the Atlas experiment, one of the big particle detectors at the LHC. 'We hope that we're just now at this threshold that we're finding another world, like antimatter for instance. We found antimatter in the beginning of the last century. Maybe we'll find now supersymmetric matter.'"
If true we would see black holes of planetary mass orbiting stars. But that is not the case, we see the usual rocky or gas giant planets.
Failing to find what the theories predict is still an advancement in knowledge.
Failing to find what a theory predicts largely excludes it (assuming the experiment isn't faulty), and is a good result and useful science. Whether or not science reporters can grok that is a job for the PR department (LHC has a good one - c.f. Particle Fever).
The Supersymmetry folks did not expect to find a Higgs boson at 127GeV. ATLAS did find what looks like a Higgs boson at 127GeV.
If there were a guarantee that this particle is the Higgs, then there wouldn't be a need to continue upwards to test Supersymmetry. But it's not guaranteed - so not finding supersymmetric pairs at the higher energies will firmly rule out the Supersymmetry model (reassigning physicists to other models) and increase the confidence that the discovered particle is the Higgs.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
To make a planet-eating black hole from an accelerator experiment you need to assume that Hawking ratiation doesn't exist (or is extremely feeble), or those black holes would evaporate instantly before they can accrete any matter. So you would end up with planet-mass black holes orbiting stars.
Even if you turned off Hawking radiation, it would still be hard for a black hole from a particle accelerator to actually eat the planet. Let's say you have an accelerator much more powerful than the LHC, with a center-of-mass energy of 1 PeV. If all that were used to produce a black hole, it would have a mass of 1.8e-21 kg. An electron or proton a single hydrogen radius away from it (which we can use as a typical intermolecular distance in the Earth for simplicity) would feel an acceleration of 1e-11 m/s^2, which is absolutely tiny compared to the electrical forces that govern motion on those scales. A small black hole like that behaves much like a neutrino - it hardly interacts with anything. And it needs to do that to grow. I think we could have lots of these inside the Earth and not even notice (dun-dun-DUUN!).
Even if you included Hawking radiation but somehow only turned it on after the black hole had consumed the planet, you still wouldn't get rid of the planet-mass black hole, as a hole of that size evaporates extremely slowly, and would have a life time of more than 5e50 years.
Planet-mass black holes could be detected via gravitational microlensing. Planets are regularly detected this way. But it may be hard to distinguish those black holes from planets. As far as I know we can't exclude a population of these in orbit around a fraction of the stars in the milky way. The accretion events, when the planets are eaten, would probably be quite bright, and might be visible as mini-supernovas.
The centre of mass energy is actually going from 8 to 13 TeV so it is not a doubling of the energy. However we are increasing the luminosity (number of protons in the beam) too so we will probably have at least twice the reach in energy that we did before. While the article makes it sound like something new looking for Supersymmetry (SUSY) is something we have been searching for since the start of the LHC.
SUSY is the leading candidate theory to explain why the higgs is so much lower in energy that the energy scale at which gravity becomes important: the Planck scale. While there are good arguments to suppose that SUSY is within range of the LHC energy I would put about as much store in a prediction of which SUSY particle will be discovered first as I would in a 14 day weather forecast: there is some science that goes into it but there are so many unknowns that the prediction is likely to be junk. Worse, while we can be pretty certain that there will be some sort of weather in 14 days there is no guarantee that there is a lightest SUSY particle: SUSY might not exist in nature although this itself would raise some interesting questions.
The observation that the electron electric dipole moment is less than 10^-29 e cm (as measured by the ACME experiment in 2013) already places strong constraints on supersymmetric partner masses, making it rather unlikely that the upgraded LHC will see anything.
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