# What if the Higgs is not found by LHC and Tev, nor anything else

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1. Aug 19, 2010

### ensabah6

Technicolor models offer ways to break EWB that do not involve higgs, but do predict new observations at LHC energies.

Based on precision WW scattering, unitarity would be violated without the Higgs mechanism.

So if the Higgs, or something that plays its role, is not found, unitarity is violated which may mean QM needs to be revised.

If the Higgs, or something like it, is not found at LHC/TEV what would be the most Nobel-prize winning route

1- reformulate QM,
2- QM is wrong, unitarity is not preserved
3- maybe there is no true Electro-weak unification
4- consider other sources of Higgs field like neutrino condensates? perhaps dark energy?
5 perhaps preons or all particles are composites?

Maybe NOT finding the Higgs is a lot like not finding the luminerous aether.

2. Aug 19, 2010

### Kevin_Axion

What if? I hope we don't find any of the mechanisms actually, the field of particle physics and theoretical physics will be of a different nature and there will be a massive stimulus in research making the field much more exciting.

3. Aug 19, 2010

### ensabah6

I know that the Higgs is needed to explain EWB and mass generation and preserve unitarity in WW scattering, but it is unsatisfactory due to hieararchy and quadratic radiative corrections, resulting in postulation of SUSY, and SUSY requires explanation for flavor change, SUSY breaking, etc. Technicolor is offered as one alternative

What about exploring the idea that (a) there is no true electroweak unification or (b) unitarity is violated and QM is only an approximation that becomes invalid

4. Aug 19, 2010

### humanino

5. Aug 19, 2010

### Kevin_Axion

I said I hope, but I will not posit that nothing will be discovered. The Higgs will be found, there is much indirect evidence for it and with SUSY it's an almost pure theory of nature.

6. Aug 19, 2010

### ensabah6

so what are the properties of weak force above unification? Is it infinite range?

7. Aug 19, 2010

### ensabah6

So you are confident that as a pure theory of nature LHC will see SUSY?

8. Aug 19, 2010

### Kevin_Axion

Sorry, let me rephrase that, if the LHC finds SUSY the MSSM will be the best theory or "purest" theory we have. Besides the MSSM, Superstring Theory will become the key area of research, this would be the Third Superstring Revolution, I believe.

9. Aug 19, 2010

### ensabah6

and if the LHC does not find it?

I do agree that LHC may help experimentally determine some of MSSM's parameters which can be used to help determine moduli parameters

10. Aug 19, 2010

### Kevin_Axion

Logically, one must believe that SUSY exists, so much research is dependent on it, when I go onto arXiv (hep-th) the papers being published are either Supersymmetric Yang-Mills Theories or Gauge/Gravity Duality (which arose from M-Theory) Theories. A lot of the ideas have a fundamental derivation from SUSY we almost need it to exist just like we needed Quantum Mechanics and General Relativity too. (correct me if my reasoning is incorrect).

11. Aug 19, 2010

### ensabah6

would you still believe in SUSY "logically" if, say by the year 2020-30, LHC and all searches for SUSY come up null?

12. Aug 19, 2010

### Kevin_Axion

If no other idea is developed as a substitution then most likely, yes.

13. Aug 19, 2010

### ensabah6

fair enough. But in this scenario, a null result for low-energy SUSY at LHC is unlikely to be the explanation for higgs stabilization since low-energy SUSY predicts little Higgs, neutralinos, and charged gluinos in LHC level energies

14. Aug 19, 2010

### humanino

Did you notice the change of slope for CC in the plot ? That is the only meaning I can imagine for "infinite range" at such high scales. Of course the interaction occurs over short ranges, but the point if that we see unification of CC with NC (and NC contains the photon which is "infinite range"). If your question on "infinite range" has another meaning, please explain.
It is not a matter of belief, the "null" is not a logical possibility. Either we see violation of unitarity as you said, and QM is falsified (most dramatic result, nobody expects that), or something unknown is proven to be there. If what is there to restore unitarity has been anticipated (single simple Higgs, SUSY, technicolor, extra-dim, combinations of previous, etc etc) we will most likely recognize it. Otherwise, there is little point into discussing what we have not anticipated, except that indeed it would be quite exciting. In all logical possibilities, something has been found. And it is not a surprise : the LHC has access to a region where the Higgsless SM is self-contradictory.

15. Aug 19, 2010

### strangerep

Could you please summarize the "indirect evidence"?

(I was still under the impression that the Higgs is in the SM only
because without it the QFT involving massive vector bosons
is nonrenormalizable.)

(?)

16. Aug 19, 2010

### ensabah6

em is infinite range, photons massless,
w, z bosons weak is short range, massive bosons.

above ew unification is the weak force infinite range or short range.

is there any reason the mechanism for giving w z gauge bosons mass must be the same as what gives fermions mass?

fermions and w bosons have electric charge. perhaps that is tied to inertial mass.

17. Aug 19, 2010

### humanino

When your scale is above the weak boson mass (like $Q^2\sim10^4\text{GeV}^2$ in the plot), you can tell the difference neither between the infinite range of the photon and the massive weak bosons (since the interaction length or time is inversely proportional to the scale) , nor between the mass of those weak bosons and the massless case (because the masses all becomes negligible anyway). That is what the plot shows, in agreement with precise calculations (rather than hand-waving).
Yes there is. It's chiral symmetry. For instance, the same dynamical chiral symmetry breaking which gives large constituent quark masses to the u and d in the proton also generate the chiral quark condensate (which is a measure of the breaking) in the vacuum $<\bar{q}q>$. This mechanism alone generates masses for the weak bosons as well. Alas, this is too small to account for the entire mass of those weak bosons. Yet this is the observation leading to the concept of technicolor, which is a repetition of a more strongly coupled unbroken sector for which the Higgs would be a pseudo-Goldstone boson (analog to the QCD pion). The technirho would regulate WW scattering for instance.

This is all beautifully described in
Electroweak symmetry breaking: to Higgs or not to Higgs
by Christophe Grojean

Last edited: Aug 19, 2010
18. Aug 19, 2010

### skippy1729

Reasoning? It would be equally logical to say that Keynesian Economic Theory must be true since we have invested so much money in it; or, Christianity must be true since so many believe it.

Skippy

PS Please note that I am not offering any opinion of Supersymmetry, Keynsian economics or Christianity, only the logic involved.

19. Aug 19, 2010

### humanino

One could as well interpret that many papers with SUSY are playgrounds/toy models which are easier to solve than the "real deal".

edit
Note that, this post neither is a judgement as to whether SUSY is realized. I am just saying that (independently of whether it is realized) SUSYs are often easier (while possibly messier).

Last edited: Aug 19, 2010
20. Aug 20, 2010

### Kevin_Axion

Belief in the context of Science is distinct, when one believes SUSY they support it until falsified. I'm saying one should believe in SUSY not due to the laborious work put into developing subject, rather because it expands our horizon of our knowledge. This doesn't just apply to SUSY but to all ideas developed by humanity, we learn and grow from the ideas we have, especially the ones that appear so natural like SUSY, the ones illuminate powerful ideas. It is these ideas that we keep until falsified. Falsification of Religion is a paradox in its own right people will continue to believe it and conclude it's true because unlike SUSY it can't be falsified. Now you see belief in Science is a product of curiosity and empirical/quantitative analysis while belief in religion is driven by faith separate from quantitative analysis, a belief that is unfalsifiable.