Higgs model predicts a universe the size of a football.

[my2cts]

Veltman states that the cosmological constant in the Higgs model takes the form C= m2M2 / 8g2 ,
which is way too large. In fact, the universe should be about the size of a theorists head or a football.
http://igitur-archive.library.uu.nl/...temVeltman.pdf
He states that "since the energy of the Higgs is distributed all over the Universe, it should contribute to the curvature of space; if you do the calculation, the Universe would have to curve to the size of a football. That’s one of the biggest problems in particle physics."
http://moodle.ncku.edu.tw/file.php/54040/References/490S10a.pdf

Is Veltman wrong or is the Higgs mechanism wrong?

 

[dauto]

Veltman's calculation is correct. It is a well known fact that the calculation for the cosmological constant within the standard model is off by about 120 orders of magnitude. The inclusion of supersymmetry improves that to off by "only" 60 orders of magnitude. :-)

That's one of the most important unsolved problems in Cosmology/Particle Physics

 

[dauto]

By the way, this is called the cosmological constant problem sometimes also called the vacuum catastrophe

 

[my2cts]

Before 1960 mass was described by an unassuming Lagrangian term such as m^2 psi^2, reflecting that we do not know the degrees of freedom giving this energy and we can not address these experimentally. It also reflects that mass is just energy in the rest frame of whatever origin. That term was sacrificed in favour of SU2 symmetry and the Higgs mechanism. Now there are two kinds of mass, two kinds of inertia. As an example the mass of a hydrogen atom is hybrid, it consists of "Higgs" contributions m_p and m_e and the non-Higgs contribution of the binding energy, potential and kinetic energy of mainly the electron.
Also the Higgs mechanism needs as many coupling parameters as it explains masses.
Make no mistake, I think the discovery of the new boson is an incredible success. LHC performed nothing short of miracle. Still, does this prove the Higgs mechanism?

 

[Bill_K]

Veltman's calculation is correct. It is a well known fact that the calculation for the cosmological constant within the standard model is off by about 120 orders of magnitude. The inclusion of supersymmetry improves that to off by "only" 60 orders of magnitude. :-)
That's one of the most important unsolved problems in Cosmology/Particle Physics

No, it is not by any means a prediction of the Standard Model. And it is not even by any means a calculation. The vacuum energy density that's famously off by so many orders of magnitude is "one Planck mass per cubic Planck length." Just a wild speculative guess, the kind you make when you have no idea what you're doing.

 

[member 11137]

By the way, this is called the cosmological constant problem sometimes also called the vacuum catastrophe

Yeh. You may have an idea of that in reading the starting point of the inner discussion here:
https://www.physicsforums.com/showthread.php?t=699015

And if you want to know more on that topic, you also may visit the Clay Institute website and look for the following document:
"Strings and geometry"

On the other side, there are alternative proposed explanations for the Higgs mass but they are extremely technical (example given: exotic R4) and I don't understand myself all details.

This was just a modest contribution to the question.

 

[my2cts]

No, it is not by any means a prediction of the Standard Model. And it is not even by any means a calculation. The vacuum energy density that's famously off by so many orders of magnitude is "one Planck mass per cubic Planck length." Just a wild speculative guess, the kind you make when you have no idea what you're doing.

So then according to you, is Veltman wrong?

 

[Bill_K]

Also the Higgs mechanism needs as many coupling parameters as it explains masses. Make no mistake, I think the discovery of the new boson is an incredible success. LHC performed nothing short of miracle. Still, does this prove the Higgs mechanism?

As we've pointed out above, the Higgs mechanism is not about fermion masses, it's about the spontaneous breaking of electroweak symmetry. This has been verified by the LHC, by the discovery of a particle with the decay modes expected of a Higgs boson. An important next step will be to verify that its coupling to fermions is proportional to their masses.

 

[Bill_K]

So then according to you, is Veltman wrong?

He's off by 120 orders of magnitude. Are you suggesting he's right?

 

[dauto]

No, it is not by any means a prediction of the Standard Model. And it is not even by any means a calculation. The vacuum energy density that's famously off by so many orders of magnitude is "one Planck mass per cubic Planck length." Just a wild speculative guess, the kind you make when you have no idea what you're doing.

I don't think anybody in their right mind would defend the calculation as being correct in the sense that it agrees with the experiment. But it is mathematically correct under the assumptions within which the calculation is made. It is more than just an speculative guess though. One plank mass per plank volume is what you get for the zero point energy of a (bosonic) field under the assumption that the standard model is the law of the land up to the Planck scale, and that there are no other contributions added to the vacuum energy. The fact that the calculation is so completely out of whack shows that at least one of the assumptions used for the calculation must be wrong. That's a very useful piece of information, useful enough to make the calculation worthwhile. The real problem is that there is no known way to get a vacuum energy density anywhere close to the observed value for the cosmological constant (CC). There are some speculative models that produce a CC exactly equal to zero, but without any logical way to get something close to zero but not zero. Right now theorist are staring at a brickwall as far as that particular problem is concerned.

 

[my2cts]

He's off by 120 orders of magnitude. Are you suggesting he's right?

I mean off course did Veltman make a mistake in drawing this conclusion from the Higgs model?
Are you suggesting he did?

 

[my2cts]

He's off by 120 orders of magnitude. Are you suggesting he's right?

Don't shoot the messenger. ;-)

 

[Bill_K]

I mean off course did Veltman make a mistake in drawing this conclusion from the Higgs model?
Are you suggesting he did?

The Higgs mechanism is part of the Standard Model, and well established. Quantum gravity, on the other hand, including physics at the Planck scale, is purely speculative. Any attempt to draw conclusions today from quantum gravity, including the value of the vacuum energy/cosmological constant, is just a shot in the dark.

People repeat this story of being 120 orders of magnitude off to get a laugh, not because there's any reason to take it seriously.

 

[my2cts]

The Higgs mechanism is part of the Standard Model, and well established. Quantum gravity, on the other hand, including physics at the Planck scale, is purely speculative. Any attempt to draw conclusions today from quantum gravity, including the value of the vacuum energy/cosmological constant, is just a shot in the dark.

People repeat this story of being 120 orders of magnitude off to get a laugh, not because there's any reason to take it seriously.

If the Higgs mechanism is so well established, why is the question "Are the branching ratios of the Higgs Boson consistent with the standard model" listed as the nr 1 unsolved problem on http://en.wikipedia.org/wiki/List_o...hysics#High_energy_physics.2Fparticle_physics ?

 

[my2cts]

The Higgs mechanism is part of the Standard Model, and well established. Quantum gravity, on the other hand, including physics at the Planck scale, is purely speculative. Any attempt to draw conclusions today from quantum gravity, including the value of the vacuum energy/cosmological constant, is just a shot in the dark.

People repeat this story of being 120 orders of magnitude off to get a laugh, not because there's any reason to take it seriously.

I think Veltman is serious. He's not out for a laugh.

 

[my2cts]

The Higgs mechanism is part of the Standard Model, and well established. Quantum gravity, on the other hand, including physics at the Planck scale, is purely speculative. Any attempt to draw conclusions today from quantum gravity, including the value of the vacuum energy/cosmological constant, is just a shot in the dark.

People repeat this story of being 120 orders of magnitude off to get a laugh, not because there's any reason to take it seriously.

Veltman draws this conclusion from the standard model, not from quantum gravity.

 

[my2cts]

No, it is not by any means a prediction of the Standard Model. And it is not even by any means a calculation. The vacuum energy density that's famously off by so many orders of magnitude is "one Planck mass per cubic Planck length." Just a wild speculative guess, the kind you make when you have no idea what you're doing.

As I stated in my initial post, Veltman interprets a constant in the lagrangian of the Higgs model, C= m2M2 / 8g2, as the cosmological constant on page 18 of linked pdf. He does make the "one Planck mass per cubic Planck length" guess.

 

[Bill_K]

The link you gave originally has disappeared, but I found what I think is the same paper http://www.nikhef.nl/pub/theory/academiclectures/Higgs.pdf. So he gets a (100 GeV)⁴ contribution to the cosmological constant, which is only off by 55 orders of magnitude.

 

[my2cts]

The link you gave originally has disappeared, but I found what I think is the same paper http://www.nikhef.nl/pub/theory/academiclectures/Higgs.pdf. So he gets a (100 GeV)⁴ contribution to the cosmological constant, which is only off by 55 orders of magnitude.

It is still there, after a bounce I retried and retrieved the paper. It is almost the same to the one you link to, but there the conclusion is weakened by adding unknown terms.

 

[mfb]

If the Higgs mechanism is so well established, why is the question "Are the branching ratios of the Higgs Boson consistent with the standard model" listed as the nr 1 unsolved problem on http://en.wikipedia.org/wiki/List_o...hysics#High_energy_physics.2Fparticle_physics ?

The list is not ordered by importance.
Out of all elementary particles, the Higgs is the one with the smallest set of measurements, and the largest uncertainty in those measurements. The branching ratios are a powerful test to see if the Higgs boson acts as expected.

 

[Chronos]

For discussion of the 'vacuum catastrophe' problem, see Quantum vacuum fluctuations, http://arxiv.org/abs/quant-ph/0105053

 

[dauto]

The link you gave originally has disappeared, but I found what I think is the same paper http://www.nikhef.nl/pub/theory/academiclectures/Higgs.pdf. So he gets a (100 GeV)⁴ contribution to the cosmological constant, which is only off by 55 orders of magnitude.

That's the improvement provided by supersymmetry that I quoted from memory as being off by "only" about 60 orders of magnitude. Veltman is not out for a laugh. His point is to show that despite the standard models successes, there are still important questions that should be answerable within the context of particle physics for which the standard model fails miserably. That does not detract from the correctness of the standard model but highlights its limitations. Presumably a correct treatment for that question can only be envisioned within the context of a wider theory.

 

[Bill_K]

That's the improvement provided by supersymmetry that I quoted from memory as being off by "only" about 60 orders of magnitude.

No it isn't. Veltman makes no mention of supersymmetry.

All these discussions are similar, but the radically different answers they get boil down to a choice of scale. The vacuum energy is ρ ~ M⁴. If you use in this the Planck mass, M_Pl = 10¹⁹ GeV, you'll be off by 120 orders of magnitude. Veltman says to use the electroweak scale, M = 100 GeV, which is only off by 55 orders. Supersymmetry so far has not been seen, so its scale keeps going up, but it appears to be 1000 GeV or more, which is off by 60 orders.

By comparison the scale from the observed cosmological constant is M_obs = 0.001 eV, which makes you wonder if they are even looking in the right place.

 

[my2cts]

No it isn't. Veltman makes no mention of supersymmetry.

All these discussions are similar, but the radically different answers they get boil down to a choice of scale. The vacuum energy is ρ ~ M⁴. If you use in this the Planck mass, M_Pl = 10¹⁹ GeV, you'll be off by 120 orders of magnitude. Veltman says to use the electroweak scale, M = 100 GeV, which is only off by 55 orders. Supersymmetry so far has not been seen, so its scale keeps going up, but it appears to be 1000 GeV or more, which is off by 60 orders.

By comparison the scale from the observed cosmological constant is M_obs = 0.001 eV, which makes you wonder if they are even looking in the right place.

Veltman just works out the consequences of the Higgs model Lagrangian, which contains a constant m²M²/8g². He does not pick a scale.

 

[Bill_K]

Veltman just works out the consequences of the Higgs model Lagrangian, which contains a constant m²M²/8g². He does not pick a scale.

The scale of the electroweak Lagrangian is set by the parameters that describe the Higgs potenial, namely μ and λ. These, along with the weak coupling constant g, determine the masses for the Higgs boson and the gauge bosons, all around 100 GeV. This is the electroweak scale, or sometimes called the Fermi scale.

Notice that his result is only one contribution to the vacuum energy. There are other contributions, equally important. With this approach, the puzzle is how the remaining contributions can nearly cancel this one.

 

[my2cts]

The scale of the electroweak Lagrangian is set by the parameters that describe the Higgs potenial, namely μ and λ. These, along with the weak coupling constant g, determine the masses for the Higgs boson and the gauge bosons, all around 100 GeV. This is the electroweak scale, or sometimes called the Fermi scale.

Notice that his result is only one contribution to the vacuum energy. There are other contributions, equally important. With this approach, the puzzle is how the remaining contributions can nearly cancel this one.

Ok, I see why you wrote "picks the scale".
The case of the Higgs model is however special in that a constant appears in the lagrangian. It is not an infinity due to vacuum fluctuations. I would therefore hesitate to lump it up with the vacuum catastrophe.

 

[my2cts]

The scale of the electroweak Lagrangian is set by the parameters that describe the Higgs potenial, namely μ and λ. These, along with the weak coupling constant g, determine the masses for the Higgs boson and the gauge bosons, all around 100 GeV. This is the electroweak scale, or sometimes called the Fermi scale.

Notice that his result is only one contribution to the vacuum energy. There are other contributions, equally important. With this approach, the puzzle is how the remaining contributions can nearly cancel this one.

One of these "other" contributions, th eEM zero point energy is probably a fluke:
http://arxiv.org/pdf/hep-th/0503158v1.pdf