Fundamental
physics is described by the so- called Standard Model. It is one of the finest
creations of humanity, allowing detailed predictions of particle physics and
improving our understanding of the universe like never before. Despite all
this, it is limited. We know that it doesn’t include gravity, for example.
So while, on
the one hand, it is one of physics' greatest tools, on the other researchers
are trying to find ways to break it. And one group might have done just that.
In a paper
uploaded on arXiv, Professor Derek Fox from Penn State University and
colleagues described two anomalous observations from the Antarctic Impulsive
Transient Antenna (ANITA) experiment. According to the paper, these signals
could not have been made by any particle within the Standard Model.
ANITA
studies ultra-high energy cosmic neutrinos. Neutrinos are particles with no
electric charge and a tiny mass. They can easily move through a planet
unscathed. If you hold up your thumb, about 100 billion neutrinos will pass
through your thumbnail every second.
Neutrinos
can interact with matter once in a while. The energies of these particular
cosmic ones are so high that they can turn into massive particles. One
particular change was expected for certain tau neutrinos (which is one of their
types or “flavors”). They can turn into tau leptons, which is a heavy version
of the standard electrons. The Standard Model has a very specific prediction
for this change, but the recent observations don’t match. The angles of the
particles detected by ANITA were much steeper than if it was a tau lepton. It
must have been something else.
So... uh, folks? I think @steinly0, some colleagues and I just broke the Standard Model https://t.co/fUJKzHLoby (using observations from ANITA and @uw_icecube)— Derek Fox (@partialobs) September 26, 2018
The team
looked at other possible candidates and nothing we have ever encountered
matched what they saw in the data. In the paper, they suggest this could be an
example of a supersymmetric particle akin to the tau lepton. Supersymmetry is a
yet-to-be-proven theory that assigns to every known particle a companion to
explain some intrinsic differences we see in particle physics but are difficult
to explain using the Big Bang Theory.
So is the
Standard Model truly broken? We can’t be sure just yet. The paper has been
submitted to the journal Physics Review D, and it will be certainly picked
apart in the peer-review process by many other groups around the world.
Even if it
doesn’t pan out, there are many other anomalies currently being investigated
that points at physics beyond the Standard Model. The fundamental theory might
survive this study, but the moment we truly break it is getting closer and
closer every day.
Comments
Post a Comment