On the right, an artificial atom generates sound waves consisting of ripples on the surface of a solid. The sound, known as a surface acoustic wave (SAW) is picked up on the left by a “microphone” composed of interlaced metal fingers. According to theory, the sound consists of a stream of quantum particles, the weakest whisper physically possible. The illustration is not to scale. (Credit: Philip Krantz, Krantz NanoArt)
via chalmers
Close-ups of an experiment conducted by John Bush and his student Daniel Harris, in which a bouncing droplet of fluid was propelled across a fluid bath by waves it generated. (Credit: Dan Harris)
via phys
The Smoluchowsi trapdoor is a simple test for any proposed exorcism of Maxwell’s demon. It is immediately obvious that an information based exorcism is of no use. The are no sensors in this simple device that collect information; and there are memory devices that would need erasure if the demon is to return to its original state. (Credit: Hemmo, M.; Shenker)
via aip
Gravity Probe B (GP-B) has measured spacetime curvature near Earth to test related models in application of Einstein’s general theory of relativity. (Credit: S. Hossenfelder, Wiki Commons)
via backreaction
The research group resolved the challenging issue attributed to solid crystals, namely widely spread emission wavelengths, and succeeded in fabricating many single-photon sources that emit photons with nearly identical emission wavelengths. (Credit: National Institute for Materials Science (NIMS))
via innovations-report
C H Figure 1: Acausality: Penrose diagram of a black hole with signature c hange at high curvature (hashed region). In contrast to traditional non-sing ular models, there is an event horizon (dashed line H , the boundary of the region that is determined by backward evolution from future infinity) and a Chauchy horizon (dash-dotte d line C , the boundary of the region obtained by forward evolution of the high-curvature re gion) (Credit: Martin Bojowald)
via arXiv
Giant alien planets known as “hot Jupiters” can induce wobbles in their parent stars that may lead to the wild, close orbits seen by astronomers. This diagram shows the relationship between wobbling stars and the orbital tilt of hot Jupiter planets. (Credit: Cornell University/N.Storch, K.Anderson, D.Lai)
via space
If a particle and its antiparticle pop into being on the event horizon, one gets sucked in. The other gets away. If the antiparticle gets sucked into the black hole, and the particle breaks free, the particle no longer has a chance to annihilate. It is now real, and not virtual. Its presence and energy count in the universe. And real radiation leaking from a black hole means that the black hole itself is slowly shrinking. (Credit: Chandra Observatory, NASA, Inglis-Arkell)
via io9
The U.S. Defense Department has highlighted China’s increasing space capabilities, however, saying China was pursuing activities aimed at preventing its adversaries from using space-based assets during a crisis.(Credit: Jaime FlorCruz – CNN Beijing Bureau Chief)
via reuters
The new planet would be an uninhabitable gas giant at least three times the size of Jupiter, and the distance from the star would be about the same distance that Saturn is from the Sun. This graphic is an artist’s conception of the young massive star HD100546 and its surrounding disk. (Credit: VP. Marenfeld & NOAO/AURA/NSF)
via astronomy
If our understanding is correct, then the universe as a whole could be in a locally stable configuration, but it could also jump to a lower energy state through a process of quantum tunneling. If that happened, the universe would collapse and we’d all go bye bye. So to our best understanding, it is possible for the universe to collapse. (Credit: )
via phys.org
Quarks have one of three “color charges,” which are analogous to the primary colors red, green and blue. Just as an atom strikes a balance between positive and negative electrical charges, particles made of quarks balance colors to reach a neutral state. In the color analogy, that means combining colors to make white. (Credit: Quanta Magazine)
via wired
There is a giant cloud of alcohol in outer space. It’s in a region known as W3(OH), only about 6500 light years away. Unfortunately it is methyl alcohol (commonly known as wood alcohol, though this stuff is not derived from wood), so it isn’t suitable for drinking. There is some ethyl alcohol (the drinkable kind).(Credit: Hubble)
via phys.org
Two tiny satellites escaping on their own doesn’t sound too bad … except it’s not the first time this has happened. On August 23rd, NASA reports that two other CubeSats set themselves free. OK, 4 out of 100 doesn’t sound too bad either … except only 12 have been launched so far, which means a quarter of the CubeSats un-tethered themselves. (Credit: NASA)
via mysteriousuniverse
Classical black holes have “no hair”, meaning that they are simply described by their mass, charge and rotation. Because of this, you could toss an object (with a great deal of entropy) into a black hole, and the entropy would simply go away. (Credit: NASA/Chandra, B. Koberlein )
via phys.org
