sábado, 31 de dezembro de 2011

The Higgs boson: another theory.


The link above shows almost all the big headlines of December 13 when scientists claim to have had a glimpse on the famous particle.

But what is the Higgs Boson?

"The Higgs boson is a hypothetical massive elementary particle that is predicted to exist by the Standard Model (SM) of particle physics. Its existence is predicted by the Standard Model to explain how spontaneous breaking of electroweak symmetry (the Higgs mechanism) takes place in nature, which in turn explains why other elementary particles have mass.Its discovery would further validate the Standard Model as essentially correct, as it is the only elementary particle predicted by the Standard Model that has not yet been observed in particle physics experiments.If shown to exist, it is expected to be a scalar boson. (Bosons are particles with integer spin, and scalar bosons have spin 0.) Alternative sources of the Higgs mechanism that do not need the Higgs boson are also possible and would be considered if the existence of the Higgs boson were ruled out. They are known as Higgsless models.

...The Higgs boson is often referred to as "the God particle" by the media,after the title of Leon Lederman's popular science book on particle physics, The God Particle: If the Universe Is the Answer, What Is the Question? While use of this term may have contributed to increased media interest,many scientists dislike it, since it overstates the particle's importance, not least since its discovery would still leave unanswered questions about the unification of QCD, the electroweak interaction and gravity, and the ultimate origin of the universe.

Lederman said he gave it the nickname "The God Particle" because the particle is "so central to the state of physics today, so crucial to our understanding of the structure of matter, yet so elusive," but jokingly added that a second reason was because "the publisher wouldn't let us call it the Goddamn Particle, though that might be a more appropriate title, given its villainous nature and the expense it is causing."

A renaming competition conducted by the science correspondent for the British Guardian newspaper chose the name "the champagne bottle boson" as the best from among their submissions: "The bottom of a champagne bottle is in the shape of the Higgs potential and is often used as an illustration in physics lectures. So it's not an embarrassingly grandiose name, it is memorable, and [it] has some physics connection too..."

Once again it is hypothetical...

The machine is massive and was a cause for some anxiety when the CERN scientists announced that they were going to switch the ON button to recreate the Big Bang. These weere the headlines:
http://www.dailymail.co.uk/sciencetech/article-1052354/Are-going-die-Wednesday.html : Are we all going to die next Wednesday?

But: not only we didn't die but nothing extraordinary really happened. If a Big Bang was to come out of the experiment it failed enourmously, and these were the headlines: http://www.nowpublic.com/world/live-webcast-bigbang-machine-lhc-collider-failed-cern-switzerland-sept-10-first-beam-roundtrip:
"Live Webcast BigBang machine LHC collider failed, CERN Switzerland Sept-10, first beam roundtrip"

Do you know any new form of life,even a simple one,the simplest one,that has emerged from this experience? neither do I...and yet, despite the best theory, despite the fact that I'm not a specialist, it doesn't take a genius to conclude that to mimic the Big Bang has the great creator of life, even if slowly, a new form of creating energy should have emerged! and I don't care how complicated all theories might be, how much mathematics and physics and all it may take, something that is supposed to mimic an event must at least look like it or have, even in a small scale, similar effects... "...Physicists use the LHC to recreate the conditions just after the Big Bang...". According to the dictionary, RECREATE means: ...to make something exist or happen again...http://dictionary.cambridge.org/dictionary/british/recreate...": So...did it happen again? I don't think so...what happen was, to me,a big waste of money...and, again, a theory.

Only two days latter after the announced glimpse of the Higgs Boson this was an headline from a very respected newspaper: http://www.dailymail.co.uk/sciencetech/article-2037722/God-particle-goes-missing-Higgs-boson-exist-say-Hadron-Collider-scientists.html: "'God particle' goes missing: Higgs boson 'may not exist' afterall say Hadron Collider scientists" it was on 15th December.

“…Anyone trying to figure out what happened during the first moments of the universe is faced with a huge problem: conditions were so different back then that the laws of physics we know today didn't always apply. And since we can't go back to the beginning of time to measure those conditions, theoreticians have to model them with mathematical formulae, the so-called Standard Model.
The model worked pretty well, but there are missing pieces. So in the 1960s, physicist Peter Higgs and several colleagues made up a hypothetical particle and used it to fill in a gap in the model, which not everyone was comfortable with…Of course, the list of mysteries is still long. Are there other types of Bosons? What is dark matter made of? Where did all the antimatter go?
Scientists admit they don't have the answers to these and many other questions, which is exciting, because you never know what they will discover along the way to solving them…” with so many misteries to solve how can they be so sure they've got the whole picture?

Some scientists have a more Earthly perspective on this matter: that it is all a big spoof, waste of money and nothing but too many confuse theories, so many difficult to prove anyway...this may also seem a pretty extreme theory but it makes some sense, read and find out:

There are other opinions such as this, or skeptical at least, as you can see here: http://www.smartplanet.com/blog/savvy-scientist/particle-of-doubt-the-higgs-boson-and-scientific-uncertainty/193

"...At the risk of making a prediction that may therefore be laughably wrong by the time you read it, I will go out onto a short, sturdy limb and guess that the scientists’ observations will be intriguingly suggestive of the Higgs… but fall well short of proof that it exists. The announcement will be rife with uncertainty, caveats, and disclaimers. I’ll further argue, however, that the physicists’ uncertainty is a hallmark of good science, not a failure of it — a point too often lost on unscientific critics.

To be sure, a certain amount of scientific grandstanding might be going on. Sometimes scientists do report results so weak and preliminary that outsiders wonder why they bothered — and the answer is often that the scientists felt a need to keep themselves or their work visible, perhaps to protect their funding. Maybe that will be the case with these Higgs announcements; maybe not. In a sense it doesn’t matter to the scientific process, though, because uncertain, preliminary results are a natural step along the road to better, firmer ones..."

But this website states yet more, and more incisive opinion: "...Informed speculation circulating in the week leading up to the announcement suggests that the research groups using two of the LHC’s instruments, the CMS and the ATLAS detectors, have seen indications that might indicate a Higgs particle with a mass around 125 GeV. One such reading could be a fluke; two starts to look like independent corroboration… but major doubts remain.And that is why my prediction that this Higgs news will be cautiously tentative is a safe bet. For starters, to rein in expectations, CERN spokespeople have already started telling some journalists that the announcement will not be definitive. (I do love a sure thing.) So the official position of CERN will be that nothing was decisively found.

During installation of the ATLAS detector. (Credit: ATLAS experiments © 2011 CERN)

It also helps that neither the CMS nor the ATLAS detector can observe the Higgs directly. Nothing can. Instead, physicists have to look for evidence of the Higgs’s spontaneous decay into a shower of other particles. From those decay byproducts, they can infer the presence of the Higgs. The catch is that the physicists can’t absolutely rule out the possibility that collisions between other particles didn’t create those byproducts and confound the results.

But the most important reason physicists will be reluctant to celebrate too enthusiastically is that their statistical confidence in the results is probably too weak. Statisticians characterize the amount of random variation in sets of data with the measure called a standard deviation (or sigma). The normal threshold for a scientific discovery is a result that shows at least 5 sigma difference from the control or baseline, which means they can be 95 percent confident it is real. (The sigma value doesn’t reflect the odds that a result is correct, only that the result is not simply a statistical fluke, like a flipped coin randomly coming up heads five times in row.)

[Correction: 95 percent is the confidence level used for most types of scientific papers. In physics, however, the standard for credibility is typically more like a one-in-a-million chance that the result is a fluke. Thanks, hawleyj@ in comments, for pointing this out.]

Those informed rumors suggest that the confidence levels of the two LHC experiments may only be 2.5 or 3.5 sigma. If so, the reports are interesting but untrustworthy observations that might turn out to be completely misleading in the long run. Lots more data will be needed to raise confidence in these observations and to rule out competing explanations, and the LHC scientists will no doubt be gathering it over the next year to dispel the uncertainty..."

So is the Higgs Boson unanimous? no, far from it...there are other opinions as you can see here:

"...The weirdness here is that the Higgs boson is famous for - or was deduced from, or invented to explain, according to taste - mass. Fundamental particles get mass by interacting with it. By the same token then, the Higgs will generally decay to heavy things. The more massive they are, the more likely the Higgs will decay to them, because it interacts most strongly with them. Conversely, things with no mass don't interact with the Higgs.

Is it all that simple to ever call it "God's particle" (name adopted by the world media)?

"...But this is not really what the Higgs is for. More specifically, before I credit a boson with being responsible for mass, I want to see it interact with mass directly, not via a quantum loop...":

Too many mysteries yet to solve so the puzzle is very, very incomplete. Statements from the scientific community show it: "...So this may see the beginning of the end of one mystery, but other mysteries remain. Much of the excitement in physics at the moment concerns unknowns. This year’s Nobel Prize, for example, went to three scientists who, in 1998, discovered that the cosmos is expanding at an ever-increasing rate, an expansion driven by a mysterious force called dark energy. Even though this research won the Nobel, no one knows what dark energy actually is.

One suggestion is that dark energy is simply another force, which, for some reason, is growing stronger over time. Another that it is a leftover from whatever came before the Big Bang; the truth is that we don’t have a clue": http://www.telegraph.co.uk/science/large-hadron-collider/8952757/The-Higgs-boson-and-the-LHC-at-last-a-clue-to-the-universe.html
Dark matter remained a mystery and yet is growing everyday and none of these brilliant theories is able to explain it? and yet the Higgs boson is supposed to explain the beginning of life which is only half of the story:where do dark matters fits in, specially when quantum physics is sometimes called the theory of everything "...Some physicists have gone so far as to describe the Higgs boson as a "God particle" that might lead to a unified "theory of everything"...": http://www.nndb.com/people/305/000169795/?

But, back to the Higgs Boson, like I asked before, is it unanimous? I mean: are all scientists, all the famous or brilliant ones, "in favour"? not at all...
One of them is actually pretty famous: "...Among the skeptics, however, is Stephen Hawking, who placed wagers with other physicists betting that the Higgs boson would not be discovered during a long and expensive effort using the large electron positron particle accelerator at the CERN laboratories in Geneva. Hawking won that gamble in 2001, when the CERN effort ended without success...": http://www.nndb.com/people/305/000169795/

Some interesting questions (and answers) about the Higgs Boson:

What does the Higgs Boson looks like and how do we know we found it?
the truth is: maybe we don't...it's what you can learn from here:

But were you expecting that the LHC would have discovered supersymmetry by now? shouldn't it have been already?
I was not expecting gluinos and squarks [the superpartners of gluons and quarks] to be lighter than a TeV [one trillion electronvolts, or about 1,000 as massive as a hydrogen atom], which is more or less what the energy limits are now. That was just because of my prejudice that we already knew indirectly that some of supersymmetry was at least was a little bit heavy. Although people are disappointed, I don’t think it’s inconsistent with what everybody was saying before the LHC turned on..."

Too many uncertainties...

"...What do you think are the prospects for the LHC finding supersymmetry?
The most likely thing with supersymmetry is we will see something either this coming year or the first year of energy upgrade. It just depends on how heavy things are and how difficult it is to see them. If that doesn’t happen then I think you should start to rethink what you’re doing. The trouble with supersymmetry is—sort of like string theory—that there’s a thousand different ways to dice it and slice it. And maybe we’re just not wrapping our minds around the problem correctly...but if WIMPS exist at 200 GeV or so, wouldn’t they already show up as missing mass in the existing data?
Yes–it’s just a question of pulling them out of the background. We would have already made some dark matter particles. Just like if the Higgs is at 125 GeV, that means that the Tevatron [Fermilab's particle accelerator, which was shut down this fall] already made quite a few of them, it’s just that we were not able to pull them definitively out of the Tevatron data. We could be in the same situation now with dark matter, that there’s already some dark matter particles but we’re not able to distinguish them yet. For example, [collisions inside the CMS detector] produce a lot of neutrinos: neutrinos are invisible as well. How do you tell the difference between a neutrino that’s invisible and a dark matter particle that’s invisible? That’s a tricky issue".

(And how conveniently elastic and flexible are all these scientific theories...)

"...But if a theory can make all sorts of different assumptions and all sorts of different predictions, then no matter what the experiments find, people can always claim that the theory was right.
Yes, so this is how you get to the multiverse. You can say, yes, I can predict our universe but I can also predict 10^500 variations of our universe–and some of those differ from our universe only in the value of the Higgs mass, let’s say. Therefore in that sense you’re never going to predict a Higgs mass. If there really is a multiverse then there is no solution to that problem. You have to figure out which of those universes you live in. It’s not that you’re going to predict which of those universes you live in...": http://blogs.scientificamerican.com/degrees-of-freedom/2011/12/08/lhc-physicist-joe-lykken-on-higgs/

Besides Stephen Hawking many others remain very skeptical:

"...Daily Mail reports that some physicists remain skeptical of the progress CERN physicists are claiming. Nobel Prize winner Martinus Veltman of the Universities of Michigan and Utrecht, said "there is no Higgs." Also Stephen Hawking
In September 2010 the popular magazine Scientific American reported on a conference in Banff inspired by Lisi's work. In December 2010 Scientific American published a feature article on E8 Theory, "A Geometric Theory of Everything." In May 2011 Lisi wrote a follow-up letter for Scientific American, describing criticism of E8 Theory and how it has progressed, noting that the theory is still incomplete, with the three generation issue remaining as a significant problem.
In December 2011, in his paper, "String and M-theory: answering the critics," for a Special Issue of Foundations of Physics: "Forty Years Of String Theory: Reflecting On the Foundations," Michael Duff argues against Lisi's theory and the attention it has received in the popular press. Duff states that Lisi's paper was incorrect, citing Distler and Garibaldi's proof, and criticizes the press for giving too much positive attention to an "outsider" scientist and theory...": http://en.wikipedia.org/wiki/An_Exceptionally_Simple_Theory_of_Everything

Funny article from mcGrath to the Daily Mail:


"Ultimately if you do not believe an intelligent creator caused all other things to come into being then presumably you accept the following:

1. One day pigs will fly (on a long enough timescale)
2. A million pound could suddenly appear on the table in front of you without cause
3. A house could be built to british standards (or similar) without intelligent design&build over a long enough time period by other forces like the wind etc. This is regardless of whether the materials exist on site or not.
4. One day humans will be able to bring back the dead

Evolutionary theory and an athiest position demand that these things can and will happen. That is one reason why i believe in a creator - because a creator seems a better explanation. "

And there are many, many skeptics of Higgs boson among nobel prize winners aswell:

"... Shelly Glashow, Boston University. Nobel prize in physics, 1979
“They said when the collider goes on
Soon they’d see that elusive boson
Very soon we shall hear
Whether Cern finds it this year
But it’s something I won’t bet very much on.”

Frank Wilczek, MIT. Nobel prize in physics, 2004
“The Higgs mechanism for generating masses is extremely attractive and has no real competition. Beyond that there’s little certainty. A near-minimal implementation of supersymmetry, perhaps augmented with ultra-weakly interacting particles, is the prettiest possibility. So I’d like several Higgs particles, Higgisinos, some ghostly stuff, and a pony.”
[Note: A Higgsino is a supersymmetric partner of a Higgs boson].

Martinus Veltman, Universities of Michigan and Utrecht. Nobel prize in physics, 1999
“You are mistaken about the Higgs search at Cern. The machine runs at half energy so far, and no one expects relevant (for the Higgs particle) results. After the shutdown [in 2013] the machine will gradually go up in energy, and if all goes well (this is non-trivial) then in about half a year the machine energy might reach design value and there might be Higgs-relevant results. So if you are thinking next week then you are mistaken. Of course, we never know what surprises nature has in store for us … It is my opinion that there is no Higgs.”

Philip Anderson, Princeton University. Nobel prize in physics, 1977
“I doubt if the opinions of one who thinks about these problems perhaps every 30 years or so will carry much weight. I’ve been busy. But the last time I thought, I realised a) that the Higgs (-A) mechanism fits the facts too beautifully not to be true, but b) it must be incomplete, because there’s no proper accounting of the vacuum energy.”
[Note: Anderson essentially described the Higgs mechanism in 1962, two years before Higgs and five other physicists published the theory.]

There are more answers in Sample’s posting.

While it’s fascinating to see how widely divergent opinions are about Higgs, I have to confess my understanding of all this is rudimentary. Perhaps the dancers and performers (my Nov. 28, 2011 posting about a dance/performance residency at CERN) will help clarify the matter for me..." more at: http://www.frogheart.ca/?p=5304

This particular article explains why the Higgs boson is so "fuzzy", a word that is used a lot at the article: http://blogs.discovermagazine.com/badastronomy/2011/12/13/mass-effect-maybe-higgs-maybe-not/ :"...Scientists at CERN cannot claim with enough confidence they have found the Higgs particle, but neither can they rule it out. There’s a good chance they have have found something, and it very well may be real, but they cannot say with complete confidence that it’s the Higgs..." meaning: they don't even know what it looks like, they don't even know for sure if it is the Higgs boson, they make it fit into their theories somehow nevertheless...confused? me too...

We may have the recipe of a cake, how it is done, the process, the ingredients, but WHY or HOW is up to the pastrycook, the chef. But of this we, God willing, will talk about later.

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