Comments on: Dark Matter Searches at Colliders – part II

By: Events with photons, b-jets, and missing Et « A Quantum Diaries Survivor

Events with photons, b-jets, and missing Et « A Quantum Diaries Survivor — Thu, 19 Jun 2008 00:03:22 +0000

[...] in a lot of detail in two posts on the searches for dark matter at colliders (see here for part 1, here for part 2, and here for part 3). Add b-quark jets to boot, and you are looking at a very rare signature [...]

By: Dark Matter Searches at Colliders - part III « A Quantum Diaries Survivor

Dark Matter Searches at Colliders - part III « A Quantum Diaries Survivor — Tue, 06 May 2008 17:54:02 +0000

[...] One intriguing solution to the problem lies in hypothesizing that a massive particle called neutralino wanders around in huge amounts, slow and unbothered by its close encounters with ordinary matter. Neutralinos would be electrically neutral, they would not interact strongly with matter, and they would be perfectly stable, lest they violate a very convenient quantum-mechanical conservation law. For more details on these hypotheses, see part II of this post. [...]

By: World of Science News : Blog Archive : links for 2008-04-29 [Uncertain Principles]

Tue, 29 Apr 2008 10:54:48 +0000

[...] Dark Matter Searches at Colliders – part II « A Quantum Diaries Survivor The saga continues (tags: physics astronomy science experiment blogs) [...]

By: dorigo

dorigo — Tue, 29 Apr 2008 06:59:07 +0000

Hello Cormac,

1) well, no, SUSY does not incorporate gravity. Some particular models which include general relativity, like SUGRA, do – but I admit I have never studied these.

2) Sure, the parallel of anti-matter is a close one to the prediction of SUSY particles. Good point… The fact is, that anti-matter did not require any hypothesis to explain why it had not been found before. SUSY requires you to buy that it is a broken symmetry (otherwise we’d have seen those particles), and it requires that a very particular combination of spin, baryon number, and lepton number is conserved to 10^-40 -otherwise protons would decay and dark matter would not be there.

3) I do not really feel the urge to have a symmetry between fermions and bosons…

Cheers,
T.

By: cormac

cormac — Mon, 28 Apr 2008 18:37:55 +0000

Excellent post, highly interesting. A couple of minor queries

1. Re ‘it allows the running coupling constants which determine the strength of the three basic interactions -strong, electromagnetic, and weak- to become one and the same at a very high energy scale…in the standard model, one sees the three couplings meet at different values of energy, whilst supersymmetry allows them to have the same value at a common energy scale’….
Doesn’t SUSY make this prediction for all four interactions, even better? I thought that was a major point, that gravity gets automatically incorporated….

2. Re SUSY breaking, I notice people like Lee Smolin make the point ‘that’s very convenient isn’t it?’ It’s strange no-one points out that the situation may be analogous to the hypothesis of anti-matter – after all, we were lucky the positron turned up so easily…

3. Re unification, it always strikes me that if all four intearctions are to be unified, something like SUSY must be right…otherwise there is no ultimate symmetry to connect the world of fermions to bosons..is this too simple a view?
Cormac O’ Raifeartaigh