Fermilab physicist explains particle physics concepts using water as an example. Credit: YouTube.
“That sounds like a job for a refractory,” I thought to myself when I came across the phys.org headline, “CERN physicists break record for hottest manmade material.”
Not really, it turns out. The temperatures are too high—about 10 trillion °F (5.5 trillion °C)—and I’m guessing timeframes are so short—that it doesn’t matter.
The temperatures were generated by physicists at CERN in Switzerland who were slamming lead particles together in the Large Hadron Collider to, according to a CERN press release, “recreate for a fleeting moment conditions similar to those of the early universe.”
There is an alphabet soup of teams of physicists at CERN—ALICE, ATLAS and CMS—who are, one way or another, interested in the “primordial soup” of our universe’s earliest moments after the Big Bang, which comes down to heavy ion particle physics (if I’m patching this together correctly).
In our materials science world, we often talk about “first principles” and things like electronic band structure, which are pretty crude concepts compared to the world these physicists dwell within.
For example, did you know that protons and neutrons are composites? They are bound up blobs of quarks and gluons, which are considered to be the basic building blocks of matter.
But even then, there are layers of complexity. For example, there are types of quarks with intriguing names like charm, beauty, up or down. At least some of these have a complement, such as the anti-charm quark.
All these quarks and gluons interact with one another, and understanding this interaction has consumed many physicist-hours. A really good, accessible explanation of the fundamental forces at play in our universe is in this CERN online article, “About the Higgs Boson.” In the video (see above), Fermilab physicist, Don Lincoln, explains the unified theory called the “Standard Model” by comparing the Higgs field to water and the Higgs boson to water molecules. (A Higgs-like boson was observed at CERN just a few weeks ago.)
The world’s leading heavy ion physicists just wrapped up their latest conference, Quark Matter 2012, which takes place about every 18 months. According to the conference website, the purpose of the conference revolves around “studying excited matter at the subatomic level to understand how the constituents dynamically arrange themselves to form ordinary matter, and to understand how this organization emerged from the primordial matter created by the Big Bang at the beginning of the universe.”
The physics of quarks, gluons and their various flavors quickly gets complicated, but somehow it continues to be compelling in the geeky slipstream of the mainstream press. It is human nature to be curious about the origins of ourselves and our world. (Perhaps as part of a supernatural urge to know our time here matters and future generations will be curious about us, in turn?) But part of me wonders, beyond scratching an intellectual itch, what is the point? That is, I hope nobody is thinking about replicating the Big Bang!
With all the focus on the search for the Higgs boson and dark matter, it is easy to forget that this vortex has been swirling in a Houston, Texas, community since at least 2005. (There is no truth to the rumor that this is is where the Houston Rockets talent disappeared!)
Credit: Melanie Innis.
For the backstory and more pictures on the wormhole—including where entrants get ejected—see this story at io9.
Is the gravity still turned on? A free falling Slinky appears to defy the laws of physics. Or does it? Credit: You Tube.
This video (about 6 minutes) of a free falling Slinky shot with a high-speed camera makes it look like the Slinky is floating in air before falling. In the first minute of the video, a Slinky is dropped from the top of a building and seems to levitate as we watch its fall in slow motion.
The filming team had the good idea to drop it from a building where the windows create a background grid. It’s amazing to watch the Slinky fall, while the bottom does not move with respect to the “grid.”
University of Sydney (Australia) associate professor Mike Wheatland of explains that that the tension in the Slinky causes the top of the Slinky “to snap down,” giving it the levitating illusion. Wheatland has done some modeling of the Slinky’s motion to explain what’s going on, which he demonstrates in the video. He says it takes only about one third of a second for the Slinky to collapse and continue its fall.
Is there any “real world” reason to understand how Slinkys fall? According to Wheatland there is.
“What you’re doing is changing something at the top, and then there is a finite time for that information about the change to get to the bottom of the Slinky. …That happens even with a rigid bar, like a steel bar, it’s just that the time is very, very short,” he says.
Asked to explain what he means about “information,”—to distinguish it from the ubiquitous use of “information,” for example, on the internet—he says “It’s a signal. Whenever you do something physically to effect a change, …you do something and there’s a cause and an effect, and between the two information has to propagate if they’re not at the same location physically.”
Hat tip to Kent Anderson at The Scholarly Kitchen.
Pendulum waves. Credit: Harvard Natural Sciences Lecture Demonstrations; You Tube.
Pendulums are fun to watch. They are hypnotizing and mesmerizing. This video is both. Apparently, it’s not a new demonstration concept, but it continues to fascinate.
The 15 bobs start together, and as their periods go in and out of phase, they appear to engage in a struggle of order versus chaos.
This demonstration was created by the Harvard Extension School as part of their natural science lecture demonstrations. It is worth reading their write-up about it before watching, but here is their brief description to get you started.
What it shows: Fifteen uncoupled simple pendulums of monotonically increasing lengths dance together to produce visual traveling waves, standing waves, beating, and random motion. One might call this kinetic art and the choreography of the dance of the pendulums is stunning! Aliasing and quantum revival can also be shown.
How it works: The period of one complete cycle of the dance is 60 seconds. The length of the longest pendulum has been adjusted so that it executes 51 oscillations in this 60 second period. The length of each successive shorter pendulum is carefully adjusted so that it executes one additional oscillation in this period. Thus, the 15th pendulum (shortest) undergoes 65 oscillations. When all 15 pendulums are started together, they quickly fall out of sync-their relative phases continuously change because of their different periods of oscillation. However, after 60 seconds they will all have executed an integral number of oscillations and be back in sync again at that instant, ready to repeat the dance.
And, in case you were wondering about the broader implications, the website offers this, “Here at Harvard, Prof Eric Heller has suggested that the demonstration could be used to simulate quantum revival. So here you have quantum revival versus classical periodicity!”