Thursday, November 10, 2005

Higgs at 105 GeV?

As Jacques Distler reminds us, we normally argue that LEP has imposed a lower bound on the Higgs boson mass: 115 GeV. Slightly below this level, maybe around 105 GeV, there can be a viable candidate that was seen as a weak signal. However, it contradicts the previous sentence about the lower bound and we usually discard the signal.

Are we doing a wise thing?

Dermíšek and Gunion argue that in next-to-minimal supersymmetric standard model (NMSSM) two things happen: first of all, with the lowest possible fine-tuning you can imagine, the Higgs is predicted at 105 GeV. Second of all, the decay channels are a bit different, the classical decay channel weakens, and therefore 115 GeV is no longer a lower bound on the mass.

In other words, it is plausible that LEP has seen a small signal for the most natural value of the Higgs mass in the second simplest supersymmetric extension of the Standard Model you can imagine. Note that the Standard Model itself was also the second simplest theory with an SU(2) gauge group you can imagine. ;-)

If this NMSSM scenario were right, I would prefer not to share Jacques' bitterness about the difficulties with observing Higgs directly at the LHC. There could be more interesting things to observe! ;-) Looks like I am not the only one who told this thing to Jacques.

1 comment:

  1. Lumos,

    The Higgs boson is going to be crucial for determining where physics goes. As Quantoken pointed out on this blog a while back, Einstein's equivalence principle between inertial and gravitational forces suggests that the Higgs mechanism controls both inertial mass and gravitational mass.

    If so, the Higgs field provides a mechanism for not only inertial mass, but gravity too.

    I've calculated that if you treat the big bang as an explosion, the outward force F=ma = 7x10^43 Newtons. This calculation uses the mass of the universe for m and the Hubble parameter to determine acceleration a, which is (recession speed variation)/(time past variation with distance) = (c-0)/(t-0) = c/t = 6 x 10^-10 m/s^2.

    This implies an equal inward pressure from the Higgs field, which can't flood-fills 3-d volume. The volume left void behind quarks in stars moving away from us is filled in by the "perfect fluid" spacetime fabric (Higgs field/gauge bosons) coming inward.

    Another way to calculate this, which gives the same result, is Newton's 3rd law: outward forces have an inward reaction force.

    In ordinary chemical explosions there is such an inward force, which is used in "implosion" type nuclear weapons to compress plutonium in the core to supercriticality (reducing the ratio of surface area to mass and thus increasing the fission probability by reducing neutron escape, by bringing nuclei closer together and of course by reducing the distances and thus neutron travel times which speeds up the chain reaction).

    In the big bang, the inward reaction is the spacetime fabric pressure which causes gravity.

    I don't think this mechanism will be taken seriously until the Higgs boson is detected. People are too prejudiced against any spacetime fabric being real at present. (I blame the string community mostly for this, as they suppressed my papers, so I'm glad you are taking the Higgs field seriously!)

    Notice that since the outward force of the big bang is 7x10^43 N (this includes the e^3 correction for higher densities with increasing distances which I proved) , the inward Higgs field pressure (force/area) is massive at close ranges. I'd imagine it is the huge pressure of the Higgs field pushing in on any place in space that gives rise to the validity of the time-energy version of the uncertainty principle, as particles forever randomly collide at high energy, and the products recombine to form energy. The vacuum of space must be a seething sea of virtual particles, and "foam" is a good term for it.

    I hope the Higgs boson is detected soon, and its properties are experimentally determined. The whole idea of spin-2 gravitons to explain the universal attractive force seems to be crazy. If they are really there, then gravitons will be (by the equivalence principle) involved in inertial accelerations as well as gravity. Surely the Higgs field is all we need for inertia and gravity!

    Best wishes,
    Nigel

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