Pasayten Institute

12/11/2022

The Ω− baryon is the strangest particle we have encountered so far. It may also be the strangest particle known to Science, literally.

With a mass of 1672.4 MeV, the Ω− baryon is heavy. As well it should be. It is comprised of three, strange quarks. The three strange quarks gives the Ω− an electric charge of three times minus one third, or minus one.

Those strange quarks also gives it the unusually long lifetime of about 8% of a nanosecond. While short by our standards - even a bit shorter than some other strange particles - a solid fraction of a nanosecond is an enormous lifetime for a particle with such an enormous mass.

As if on brand, this strangest of the strange particles lives for so long precisely because its made from only [strange quarks](https://pasayten.org/the-field-guide-to-particle-physics/strange-quark) . The strange quarks, you might recall, struggle to decay. They wouldn’t decay - actually - if not for a mild identity crisis.

The strange quarks talk to other particles by photon, gluon and the W-boson. That is, in addition to the electromagnetic force, strange quarks communicate via both the strong and weak nuclear forces. From the strong force’s perspective, strange quarks are distinct. Just like the up and down quarks. Nobody is confused, all that that subnuclear goo respects their identity as strange quarks.

The weak force hedges a bit. The W-boson in particular is a little confused on who is who, and from its perspective down and strange quarks are a little mixed. Just like North and West mean slightly different things to a compass or a cartographer, down and strange quarks appear slightly different to the strong and weak forces. They’re almost aligned, but not quite.

As a result, the strange quark decays by W boson as if it were a down quark. That decay is amplified by the strange quark’s heavy mass, but its still a small effect. The weak nuclear force is… well… weak.
Being made of three strange quarks, the Ω− baryon decays once one of its constituents does.

11/29/2022

Holiday travel is on the rise, and as you climb in altitude so too is your exposure to cosmic radiation! Not that you should worry. It’s a fun opportunity to relish in the ever so slightly increasing presence of muons.

Although if particle showers were visible to us, however innocuous, they would put on quite a show!

If you haven’t yet heard our multipart piece on cosmic rays and muons, a trip from depths of space to the depths of the Greenland ice sheet, check out our bio!

11/26/2022

Prepare for trouble! And make it double! Today we confront the two Cascade or Ξ /ksee/ baryons which each have a /pair/ of strange quarks.

Ξ-minus checks in with a mass of about 1322 MeV, making it the heaviest baryon we’ve encountered so far. This is just as well, as it comprised of two of those heavier, strange quarks. Together with a third, down quark, it also has a total electric charge of minus 1.

Ξ0 is just a little bit lighter with a mass of 1314 MeV. Its two strange quarks are paired with an up quark, which gives it an electric charge of zero.

Like many strange particles, the cascades take quite a while to decay. The
Ξ− takes a solid fraction of a nanosecond, the usual time it takes to convince one of those strange quarks to decay into an up quark. The result? The strange-strange-down bag of quarks converts to up-strange-down bag, otherwise known as the Λ0. As usual, that decay is accompanied by some other junk, and in this case the net result is pi minus.

As we’ve already seen, the Λ0 and the pi minus are both unstable themselves. The former converts to either a proton or a neutron and the latter typically decays to a muon which decays to an electron.

If you tried to sketch that all out, you’d find a /long/ decay chain with /a lot/ of different particles (swipe!). This gives the cascades their name.

Producing just one Ξ-baryon results in a cascading shower of particles all the way down to familiar, stable stuff like protons, neutrons and electrons (and their accompanying neutrini).

11/22/2022

Accounting for Cosmogenic Muons in ! One of our favorite stories of applied !

https://www.linkedin.com/pulse/cosmogenic-muons-paleoclimatology-sean-downes/?trackingId=gusK5o1cQ9u4QlGXwzS4Rw%3D%3D

11/15/2022

Flip a coin 10 times. Would *you* flip if it landed on heads 10 times in a row?

Flip that same coin a million times. Would that 10-headed streak feel so surprising now?

A funny thing happens when our data scales. The statistical fluctuations within in scale too. Without the proper context, this can lead to some significant misinterpretation of that data.

Today we explore how statistics can be counter intuitive, and how it can lead folks to overestimate the significance of “scientific evidence”.

Today we explore the games statistical context can play with your mind.

11/14/2022

In case you missed our podcast series, we converted it into a white paper:

Cosmic Rays are particles from deep in outer space that impinge upon Earth at extreme velocities. They're a somewhat rare sort of radiation.

11/10/2022

Thinking of running a closed beta a GR course in the near term. It would probably be based on this text. Nuts and bolts, chalkboard and talking videos. Nothing fancy. Any interest out there?

11/10/2022

Sakurai's textbook "Modern Quantum Mechanics" starts with angular momentum, rather than X and P. It eases the reader into the mathematics with two-dimensional matrics, rather than all kinds of fancy functional analysis and infinite-dimesnsional vector spaces flattened down into "phyiscs notation".

Quantum Mechanics isn't easy. But as a source of computation technology - and subsequently policy making - it's coming straight for us.

If you're looking to get started, be like J.J. and start with Spin!

There's plenty of time to learn about the infinite-dimensional representations of Heisenberg Algebras after you master the main ideas of Quantum Theory.

Jun John Sakurai (桜井 純, Sakurai Jun, January 31, 1933 – November 1, 1982) was a Japanese-American particle physicist and theorist.

11/08/2022

Weighing in at 1192 MeV, the middle-weight Σ-baryon is also the the electrically neutral one.

While the decay resistant charged baryons - with their unusually long lifetimes - certainly qualify as “strange” particles, the Σ0 feels far less strange. At least at first.

It decays rapidly. Tens of trillions of times faster than its charged siblings.

If you’re into really small numbers, or just to measure time in seconds, that’s a decimal point followed by 19 zeroes before you get 7 and then a four. 0.000000000000000000074 seconds!

That’s too short a time for us to fathom, but its about right for an unstable particle that heavy.

Remember, it is STRANGE that the typical lifetime for strange baryons like
Λ0 or the charged Σ’s can be measured in nanoseconds. An eternity by comparison!

So why does the Σ0 baryon decay so quickly? OR why do we even consider it to be in the “Strange” family?

Well it has a strange quark, which is qualifying enough. Actually, it has one up each: up, down and strange. Just like the Λ0 baryon. It also decays to that famous Λ0 baryon by emitting a photon.

So really, it’s just an “Excited” version of the Λ0. All that extra energy gets pushed out by the photon, which decays to the Λ0, who then stays around for a STRANGELY LONG TIME before decaying itself.

11/08/2022

The Stern-Gerlach experiment gives a natural avenue for the study of . Rather than fumble with function spaces or infinite-dimensional matrices, we can instead work with : a simple, two-dimensional quantum state vector.

Chaining those detectors together gives us a neat way to start thinking about quantum logic too. You gotta start somewhere with

We’ve started a mini-series over at our YouTube channel. Go hit the link in our bio for more.

11/08/2022

Should we credit fundamental, Scientific research with advancements in technology? In medicine?

Particle accelerators have given us medical imaging technology like MRI machines and PET scans. But is it fair to assign all that credit to particle physics directly?

"Directly" is probably too linear. STEM research and development is an ecosystem. The economic idea of "growth" is probably a better framework for understanding these advancements.

Yesterday I shared a piece about how particle physics recoiled from the failed search for Weak Scale Supersymmetry. Here's the companion to that piece. It talks about where we should go from here, and why.

Scientific Progress is and should be measured by what we actually learn, not by the difference between what we expect to find and what we did.