- #1
bluecap
- 396
- 13
I just finished Gordon Kane superb book "String Theory and the Real World" in one sitting. It answered most of my current questions about the field. I need some hard data. He mentioned:
"More generally, where did the predictions for superpartner masses come from? Until recently there were no theories predicting the values of superpartner masses. The arguments based on 'naturalness' are basically like saying he whether tomorrow should be the same as today. The opposite of naturalness is having a theory.
"For example, the compactified M-theory example we will examine below predicts that gluinois will have masses of about 1.5 TeV, and decay patterns implying about 500 gluino production events will have to be produced for each detector before a signal from them can be seen above the backgrounds that can resemble singal events..."... "The compactified M-theory predicts that three kinds of superpartners will be observable if sufficient numbers of collider events are producted at the LHC with its current energy and intensity (gluinos and charged and neutral winos), but that all other superpartners require higher enregy or intensity colliders. More importantly, the prediction is that none of these should have been seen in the LHC data until the run beginning in 2017. Claim they should have been seen would be valid given so called naturalness arguments, but are wrong in actual theories. Many of us think that is a misuse of the idea of naturalness, but it is the fashionable use.
<skipping many chapters>
"In the compacified M-theory all moduli are stabilized. Their generic vacuum values are calculated, as is the lightest modulus mass, which turns out to have to be approximately equal to the gravitino mass. The supersymmetry breaking scale where F-terms are non zero (about 10^14 GeV) and the gravitino mass (about 40 TeV) are calculated. The full soft-breaking Lagrangian is calculated at high and low scales. Squark, selpton and high-scale Higgs sector masses are of the order of the gravitino mass. Running to the low scale brings M(hu) down to about 1 TeV, which is important for electroweak symmetry breaking. An exciting and unexpected discovery was that the masses of the visible sector gauginos (gluinos and winos and binos) have no contribution from the large chiral fermnion F-terms for general reasons, and these have masses near a tera-electronvolt (gluinos about 1.5 TeV, winos and binos about 0.5 TeV). Thus these states are predicted to be observable at LHC during the run beginning in 2016 if it reaches design energy and intensity. The hierarchy problem is generically solved"
My inquiries:
Ok. How is the constrains for the 0.5 TeV winos and binos? Have we not yet reached 0.5 TeV?
Second. Aren't computations that can solve the Hierarchy Problem by proposing superpartners part of
Naturalness?
"More generally, where did the predictions for superpartner masses come from? Until recently there were no theories predicting the values of superpartner masses. The arguments based on 'naturalness' are basically like saying he whether tomorrow should be the same as today. The opposite of naturalness is having a theory.
"For example, the compactified M-theory example we will examine below predicts that gluinois will have masses of about 1.5 TeV, and decay patterns implying about 500 gluino production events will have to be produced for each detector before a signal from them can be seen above the backgrounds that can resemble singal events..."... "The compactified M-theory predicts that three kinds of superpartners will be observable if sufficient numbers of collider events are producted at the LHC with its current energy and intensity (gluinos and charged and neutral winos), but that all other superpartners require higher enregy or intensity colliders. More importantly, the prediction is that none of these should have been seen in the LHC data until the run beginning in 2017. Claim they should have been seen would be valid given so called naturalness arguments, but are wrong in actual theories. Many of us think that is a misuse of the idea of naturalness, but it is the fashionable use.
<skipping many chapters>
"In the compacified M-theory all moduli are stabilized. Their generic vacuum values are calculated, as is the lightest modulus mass, which turns out to have to be approximately equal to the gravitino mass. The supersymmetry breaking scale where F-terms are non zero (about 10^14 GeV) and the gravitino mass (about 40 TeV) are calculated. The full soft-breaking Lagrangian is calculated at high and low scales. Squark, selpton and high-scale Higgs sector masses are of the order of the gravitino mass. Running to the low scale brings M(hu) down to about 1 TeV, which is important for electroweak symmetry breaking. An exciting and unexpected discovery was that the masses of the visible sector gauginos (gluinos and winos and binos) have no contribution from the large chiral fermnion F-terms for general reasons, and these have masses near a tera-electronvolt (gluinos about 1.5 TeV, winos and binos about 0.5 TeV). Thus these states are predicted to be observable at LHC during the run beginning in 2016 if it reaches design energy and intensity. The hierarchy problem is generically solved"
My inquiries:
Ok. How is the constrains for the 0.5 TeV winos and binos? Have we not yet reached 0.5 TeV?
Second. Aren't computations that can solve the Hierarchy Problem by proposing superpartners part of
Naturalness?
