using repurposed muon detectors to see inside Mayan archaeological ruins. also: “Foreign physicists building iron rooms beneath the pyramids! To search for secret chambers based on the evidence of cosmic particles.”
Tag: physics
LHC
The Large Hadron Collider (LHC), a 27 kilometer long particle accelerator straddling the border of Switzerland and France, is nearly set to begin its first particle beam tests. CERN is preparing for its first small tests in early August, leading to a planned full-track test in September – and the first planned particle collisions before the end of the year. The final step before starting is the chilling of the entire collider to -271.25 C. Here is a collection of photographs from CERN, showing various stages of completion of the LHC and several of its larger experiments (some over 7 stories tall), over the past several years.
big machine porn
stephen hawking in legos
Materials Genome Project
We want to do for Materials Science what The Human Genome Project did for Biotechnology
Asymmetric Inflation
Colossal structures larger than the visible universe – forged during the period of cosmic inflation nearly 14B years ago – may be responsible for a strange pattern seen in the big bang’s afterglow
Leggett inequality
A team of physicists in Vienna has devised experiments that may answer one of the enduring riddles of science: Do we create the world just by looking at it? Leggett’s theory was more powerful than Bell’s because it required that light’s polarization be measured not just like the second hand on a clock face, but over an entire sphere. In essence, there were an infinite number of clock faces on which the second hand could point. For the experimenters this meant that they had to account for an infinite number of possible measurement settings. So Zeilinger’s group rederived Leggett’s theory for a finite number of measurements. There were certain directions the polarization would more likely face in quantum mechanics. This test was more stringent. In mid-2007 Fedrizzi found that the new realism model was violated by 80 orders of magnitude; the group was even more assured that quantum mechanics was correct.
Satan Stargate
who knew! “the LHC will bring satan to earth”
X-ray paleontology
X-rays now make it possible for paleontologists to study opaque amber, previously inaccessible using classical microscopy techniques.
Superconductivity
293 Kelvin, but at > 200 gigapascal, so not deployable. this is the kind of pressure that breaks diamond anvils. Earlier milestones: 200 Kelvin, 185 Kelvin – the field has improved by ~100 kelvin since i started paying attention in the early 90s.
Graphene superconductors exist, as of 2019:
his lab at MIT had found superconductivity in twisted bilayer graphene — a 1-atom-thick sheet of carbon crystal dropped on another one, and then rotated to leave the 2 layers slightly askew. The discovery has been the biggest surprise to hit the solid-state physics field since the 2004 Nobel Prize–winning discovery that an intact sheet of carbon atoms — graphene — could be lifted off a block of graphite with a piece of Scotch tape. And it has ignited a frenzied race among condensed-matter physicists to explore, explain and extend the MIT results, which have since been duplicated in several labs. The observation of superconductivity has created an unexpected playground for physicists. The practical goals are obvious: to illuminate a path to higher-temperature superconductivity, to inspire new types of devices that might revolutionize electronics, or perhaps even to hasten the arrival of quantum computers. But more subtly, and perhaps more important, the discovery has given scientists a relatively simple platform for exploring exotic quantum effects. “There’s an almost frustrating abundance of riches for studying novel physics in the magic-angle platform”
Also as of 2019, new states of superconductivity are being found:
Superconductivity has been shown in monolayer crystals of, for example, molybdenum disulphide or tungsten disulfide that have a thickness of just 3 atoms. ‘In both monolayers, there is a special type of superconductivity in which an internal magnetic field protects the superconducting state from external magnetic fields’. Normal superconductivity disappears when a large external magnetic field is applied, but this Ising superconductivity is strongly protected. Even in the strongest static magnetic field in Europe, which has a strength of 37 Tesla, the superconductivity in tungsten disulfide does not show any change. However, although it is great to have such strong protection, the next challenge is to find a way to control this protective effect, by applying an electric field.
Superinsulators
When they tried to pass a current through the material, the researchers noticed that its resistance suddenly increased by a factor of 100K once the temperature dropped below a certain threshold. The same sudden change also occurred when the researchers decreased the external magnetic field. Like superconductors, which have applications in many different areas of physics, from accelerators to magnetic-levitation (maglev) trains to MRI machines, superinsulators could eventually find their way into a number of products, including circuits, sensors and battery shields.
Gregor J. Rothfuss 