A few years ago, when my children were infants, I used to amuse myself (and, I hoped, pacify them) by changing the words to nursery rhymes and other children's songs. I made them all about physics and astronomy. "Twinkle twinkle little star" was a gimme; the Muppets' "Rainbow Connection" became a song about Pluto ("Why are there suddenly only eight planets?"). My favorite went to the tune of the Itsy Bitsy Spider: "The Higgsy Higgsy boson was in the LHC..."
As my children (now kindergarteners) can tell you, "LHC" stands for "Large Hadron Collider," the enormous particle accelerator at the CERN laboratory near Geneva. And the Higgsy Higgsy boson? Physicists who are not straining to fit a song's meter know it better as the "Higgs boson," named in honor of British physicist Peter Higgs. (A "boson" is a kind of particle; other familiar bosons include photons, quantum particles of light.)
About fifty years ago, Higgs and several colleagues hypothesized that a new type of elementary particle with specific properties should exist. In fact, they suggested that the new particle should be so ubiquitous that we are all bathed in a sea of them all the time, without even noticing them. The idea behind the Higgs particle was to give other particles their mass--to account for why some elementary particles trudge along as heavyweights or welterweights (on the subatomic scale) rather than zooming around at the speed of light.
You can think of Higgs particles as invisible soccer balls, constantly being kicked back and forth between the particles that we observe. Rather than zipping straight across the field at the speed of light, the particles that are "kicking" or interacting with the Higgs particles follow zigzag paths, and hence take longer to move from one place to another. We interpret their slower rate as a sign that they are lugging a heavy load, that is, that they have some mass.
The Higgs particle has been on my mind for a long time. Back in college my friends used to tease me for my Ahab-like obsession with the funny-sounding particle. (Naturally I assumed that they were jealous that I got to spend my time daydreaming about the origin of mass.) My first scientific article, written almost twenty years ago, focused on the hunt for the Higgs: one more insignificant paper piled on the mountain that had already accumulated on the topic. More recently, I have been working with colleagues to understand what roles Higgs particles might have played in the very early universe, mere moments after the big bang--and whether the quantum jitter of Higgs particles back then might have left observable signals in the skies today.
Indeed, finding the Higgs particle has been at or near the top of particle physicists' wish list for decades. Although there have been tantalizing hints of the Higgs in previous experiments--including as recently as last summer--none of those results panned out.
That's why I sat mesmerized a few weeks ago, watching the live-streaming feed of a press conference at CERN. The video was choppy, cutting out every few seconds. Being an optimist, I chose to interpret the poor signal quality as due to heavy internet traffic: wasn't everybody trying to watch the teleconference at 8am Eastern time?
At the press conference, physicists from two independent groups presented updates on their searches for the Higgs particle at the LHC. They necessarily stopped short of claiming successful detection--that will require considerably more data to rule out the possibility of statistical flukes, background noise from non-Higgs processes that could mimic a genuine Higgs signal. But what they presented was the most compelling evidence to date that the Higgs boson might actually exist, pretty much right where theorists hoped it would be.
There are many reasons to be cautious before jumping to premature conclusions. For my money, you can't do better than physicist Matthew Strassler's blog for a smart, accessible guide to the finer points involved.
For all that, I still get a tingly feeling when I think back to that press conference and the possibilities on display. Searching for the Higgs particle has occupied physicists for half a century. And yet before my kids finish first grade, we very well could know whether the Higgs particle exists, at least in the form we most expect to find. And that would be worth singing about.
Sadly, that's the state of affairs in theory, right now. We have an epicycle description of the vacuum (look at the full standard model Lagrangian, if you want to see it... it's as monstrous as useless), but we lack any idea what's between the low energy vacuum and the Planck scale and nature doesn't seem to want to give that information away easily.
If LHC delivers nothing but the Higgs, it will refine the standard model parameters but we will not have made any essential progress in physics. At the very least we need a few light superpartners or something completely unexpected. That's the news I am waiting for... the unexpected that drives science forward in giant leaps.
Here is the direct link to Matt Strassler'Âs recent blog entry mentioned in this article that discusses the pros and cons of whether the extant LHC results support the existence of the Higgs boson:
http://proÂfmattstrasÂsler.com/aÂrticles-anÂd-posts/thÂe-higgs-paÂrticle/holÂiday-higgsÂ-hints-conÂfidence-inÂspiring-orÂ-not/
While I am not qualified to comment on most of this discussionÂ, my training in the field of financial econometriÂcs motivated me to take special notice of these statements in it:
"There might be no Standard Model-like Higgs particle in nature; there could be one with a non-StandaÂrd Model production rate, or non-StandaÂrd Model decay rates ... Given that we are in the process of testing the Standard Model, we should be careful about assuming it in building an evidentiarÂy case."
Strassler is concerned that preliminarÂy test of the existence the Higgs boson results could be due to non-StandaÂrd Model phenomena even. That is why he is cautioning against prematurely interpreting the extant evidence as sufficient evidence in the Higgs boson motivated specifically by the Standard Model. And why he advocate waiting until more powerful tests using the LHC are conducted before exclaiming joyously that the Standard Model Higgs boson has been observed.
So, here's to an exciting year ahead on that front!
The Tightwire Guy
I have one concern about your choice of wording here:
"Strassler is concerned that..."
Unless you talked to Strassler to confirm what he meant by the text you quoted from his blog entry, perhaps you should have less-presumptuously said:
"My interpretation of these statements is that Strassler is concerned that..."
This would have more clearly signaled to a reader of your post that you are offering your interpretation of the text you quote versus implying that your interpretation carries an authority that is greater than mere interpretation (e.g. that you also discussed this statement with him). It may seem like a minor issue but by doing so you would have also more clearly signalled to a reader that you are open to hearing interpretations from those readers. Which I am assuming you are, right?
And for bending your "ear" on this matter, please accept this link as a token of apology if I offended you in any way:
http://www.quora.com/Particle-Physics-Beyond-the-Standard-Model/What-are-current-alternatives-to-the-standard-model-of-physics
Until next time...
The Tightwire Guy
My comments are not meant to suggest that scientists should do something different. It has, however, become a case of digging deeper and deeper with increasingly smaller shovels. Will that process ever stop?
Consider this alternative to thinking of quanta as "particles that provide" properties to other quanta:
If one thinks of a quanta as the LOCATIONAL CENTERED Â (which identifies its "point" in space at any point in time) STATISTICAL CHARACTERISTICS of the OBSERVABLE RESULTS of the INTERACTIONS (which describes the randomness of its interaction with other quanta) of SPACE FILLING OSCILLATING FIELDS (hence, the wave-like characteristic of quanta), then concepts relevant to the "quantum realm" such probability wave functions, quantum harmonic oscillator, acoustic resonance, the uncertainty principle, and the dual particle-wave nature of quanta seem pretty obvious.Â
Furthermore, this way of visually/describing quanta makes it easier to visualize why lowering the energy of a space-constrained collection of quanta could result observing the Bose-Einstein condensate, one of the most unlikely/strangest phenomenon that one could imagine if one thinks of
quanta as "particles".
With these thoughts in mind, think instead of elementary particles as merely the ACCOUNTING (the local record-keeping) of what can be observed due to the quantum field interactions. It follows that a more accurate way to describe the Higgs boson is that it might ACCOUNT IN A RECORD-KEEPING SENSE for the mass of certain particles due to the interaction of the Higgs FIELD with the other quantum fields. Or more succinctly, the Higgs boson accounts for the mass of other elementary particles even though Higgs bosons do not "provide" them with it.
The Tightwire Guy