When the Higgs Boson discovery was announced by physicists from CERN, it stirred the world. A 50 year hunt was finally over and we had evidence that this particle, lying at the heart of the standard model of the universe, actually existed.
Surely then, when further observations were made and results from the Tevatron were analysed and the Higgs Boson was found to behave exactly as expected, physicists would be celebrating. But not this time…
So far, the Higgs boson had been observed to decay into photons and W and Z bosons, giving confirmation that it gives mass to these force carrying particles. Since it had not been seen to decay into quarks, or other particles which make up matter, it left open the possibility that these particles get their mass from elsewhere…
A discovery like this would revolutionise the Standard Model. It is already known that the SM doesn’t have any explanation for Dark Matter or gravity, so the deviation from expectation might tell us more about the SM and how it could include these properties.
Mildly disappointing results from the Tevatron however, although lying at the 3-sigma level of probability, might show the Higgs Boson decaying into a pair of bottom quarks. Although it is good news for the Higgs -it follows expectation from the standard model- it means we’ll have to look elsewhere for a theoretical explanation of gravity and dark matter.
Tag Higgs
Higgs Boson Found?
During the seminar this morning, it was announced that “A new boson has been found, possibly the Higgs”.
This is the news that physicists around the world have been waiting for: The first tantalising glimpse of the now famous elusive boson.
If it seems like the celebrating doesn’t quite satisfy the years of experimenting in attempts to find this particle, that’s simply because noone wants to jump to conclusions just yet…
The find was at a significance level of 5 when two datasets were combined, but 4.9 when all of the data was put together. The higher the significance level- the more likely the discovery. (and the more leeway we have to start the street parties).
Hopefully when we have more results and more hindsight, the significance level will increase and the discovery will be confirmed.
What does it mean? Why is it so useful that the particle has been found? Modem science starts with theories. The theories become confirmed when experimental evidence backs them up. It’s a long way since the old days when it was the other way round- perform an experiment then theorise how it works.
The Higgs boson lies at the heart of the Standard Model- Our most up to date theory of the universe. Physically finding the particle was therefore imperative to ensure the theory was consistent with reality!
Also, further analysing the data and progressing with the experiments at the LHC will provide a deeper understanding on the behaviour of the particle- and our universe with it.
According to the Standard Model, The Higgs boson, (or Scalar boson technically, as it follows no particular direction in a magnetic field) makes up the “Higgs Field” which permeates the universe. Particles moving through this field interact with the bosons, giving them the properly of mass. This is like trying to walk in a swimming pool, pushing against the water molecules slows you down. As molecules move faster, they become heavier as they interact with more bosons. Ergo- they get heavier. This prevents massive particles from ever reaching the speed of light. Their mass will tend to infinity as they reach the speed of light- such that it requires an infinite amount of energy to accelerate them to that speed.
The reason photons can reach that speed is that they pass through the Higgs field without interacting.
Fantastic news then, if the particle really has been observed for the first time in human history!
Professor Higgs was delighted, announcing his surprise at the discovery being made during his lifetime.
Professor Steven Hawking lost a bet.
If confirmed, it will be by far the most exciting news in the scientific community of the past few years.
Where is the Higgs, Anyway? New Announcements Coming Wednesday
You can almost taste the anticipation as Humans inch ever onwards on our most famous endeavour to date- The search for the Higgs Boson.
Taking the limelight in the science media for a couple of years now, what is it about “The Search” that makes it so popular with the public? Is it the expensive technology at CERN? The exotic underground particle collider? Or the mystery behind the particle which, although unobserved, underpins our most current theories of the universe?
Another explosion of interest has taken hold as CERN have announced a seminar this Wednesday to deliver the most recent news about the Higgs search. During this seminar, the preliminary results of the 2012 data analysis will be released by ATLAS and CMS. What exactly will these results reveal? That is exactly the question which has sparked this fresh excitement. With the results from 2011 looking promising, but still unreliable, this set will hopefully give us a better idea of whether we’re looking “in the right place”. Will we find the Higgs for definite? Probably not just yet, but the results so far are increasingly promising, perhaps we really will find the Higgs in 2012…
The search isn’t just being carried out at CERN. There are other colliders such as the Tevatron in the US which are engaging in the same data-collection runs as the LHC. The LHC just takes the spotlight as it’s the most powerful collider in the world. The results from CERN which hit the news around Christmas past were reinforced by the Tevatron but still not quite within experimental significance. (Real physics is never [yes/no], but [probably/probably not)]. Are we at the final hurdle? The results so far suggest we are likely to be close, but hopefully this Wednesday, the world will know whether the Higgs is as close as we hope.
If the particle is found, it will be extremely important evidence for the Standard Model, which underpins our most current understanding of the Universe. The equation for the Standard Model doesn’t just suggest the existence of the Higgs though, it requires it. Without a Higgs Boson, the Standard Model does not work. If we find no evidence for the particle then, we enter a new voyage of discovery as a new theory must be constructed to understand and predict the Universe and its inner workings. Either way, it will be one of the most important discoveries of modern physics.
Look out for the seminar on Wednesday, and check back to Musings for more news and analysis of the announcement.
Musings of a Scientist 