# gst: vacuum fluctuations (even in complete darkness)

<< physics is increasingly discovering how our universe is shaped by fluctuations of physical fields, which not only lead to tiny shifts of spectral lines of atoms, but moreover may cause the evaporation of black holes, and are ultimately responsible for the large-scale structure of our universe,  >>

AA  << have now made a large leap toward controlling strongly enhanced vacuum fluctuations much faster than typical timescales of virtual photons. To this end, they created a specialized semiconductor structure in which electrons are extremely strongly coupled to the light fields of tiny antennas designed for the so-called terahertz spectral range. As a result, vacuum fluctuations of light and matter fields participate in the interaction, strongly increasing the presence of virtual photons—even in complete darkness. >>

Understanding vacuum fluctuations in space. University of Regensburg. Aug 10, 2020.

https://phys.org/news/2020-08-vacuum-fluctuations-space.html 

<< The abrupt modification of the vacuum ground state causes spectrally broadband polarization oscillations confirmed by (AA) quantum model. In the future, this subcycle shaping of hybrid quantum states may trigger cavity-induced quantum chemistry, vacuum-modified transport or cavity-controlled superconductivity, opening new scenarios >>

M. Halbhuber, J. Mornhinweg, et al. Non-adiabatic stripping of a cavity field from electrons in the deep-strong coupling regime. Nat. Photonics. doi: 10.1038/ s41566-020-0673-2. Aug 10, 2020.

https://www.nature.com/articles/s41566-020-0673-2

# gst: temblors with a 'boomerang' effect

<< The temblor shot eastward across a deep gash in the seafloor, and then zipped back to where it started at incredible speeds. It moved so fast it created the geologic version of a sonic boom. >>

Maya Wei-Haas. Weird ‘boomerang’ earthquake detected under the Atlantic Ocean. Aug 10, 2020.

https://www.nationalgeographic.com/science/2020/08/weird-boomerang-earthquake-detected-under-atlantic-ocean/   

AA << present an analysis of the 2016 Mw 7.1 earthquake on the Romanche fracture zone in the equatorial Atlantic, (..) (They) show that this rupture had two phases: (1) upward and eastward propagation towards a weaker region where the transform fault intersects the mid-ocean ridge, and then (2) an unusual back-propagation westwards at a supershear speed towards the centre of the fault. (..) deep rupture into weak fault segments facilitated greater seismic slip on shallow locked zones. This highlights that even earthquakes along a single distinct fault zone can be highly dynamic. Observations of back-propagating ruptures are sparse, and the possibility of reverse propagation is largely absent in rupture simulations and unaccounted for in hazard assessments. >>

Hicks, S.P., Okuwaki, R., et al. Back-propagating supershear rupture in the 2016 Mw 7.1 Romanche transform fault earthquake. Nat. Geosci. (2020). doi: 10.1038/ s41561-020-0619-9. Aug 10, 2020.

https://www.nature.com/articles/s41561-020-0619-9 

# brain: flies, mice and humans, comparable behaviors for balance and motor control

<< Comparative developmental genetics indicate insect and mammalian forebrains form and function in comparable ways. However, these data are open to opposing interpretations that advocate either a single origin of the brain and its adaptive modification during animal evolution; or multiple, independent origins of the many different brains present in extant Bilateria. Here, (AA) describe conserved regulatory elements that mediate the spatiotemporal expression of developmental control genes directing the formation and function of midbrain circuits in flies, mice, and humans. These circuits develop from corresponding midbrain-hindbrain boundary regions and regulate comparable behaviors for balance and motor control. (They) findings suggest that conserved regulatory mechanisms specify cephalic circuits for sensory integration and coordinated behavior common to all animals that possess a brain. >>

Jessika C. Bridi, Zoe N. Ludlow, et al. Ancestral regulatory mechanisms specify conserved midbrain circuitry in arthropods and vertebrates. PNAS. doi: 10.1073/ pnas.1918797117. Aug 3, 2020.

https://www.pnas.org/content/early/2020/07/31/1918797117  

Humans and flies employ very similar mechanisms for brain development and function. King's College London.  Aug 3, 2020.

https://phys.org/news/2020-08-humans-flies-similar-mechanisms-brain.html

Also

'mosca in bottiglia' in: 2066 - voli a casaccio. Notes. Oct 01, 2006.   (quasi-stochastic poetry)

https://inkpi.blogspot.com/2006/10/2066-voli-casaccio.html

Also

keyword 'flies' in FonT

https://flashontrack.blogspot.com/search?q=flies

# astro: runaway cooling of intracluster gas during a silent black hole

<< supermassive black holes play a fundamental role in regulating the formation of stars throughout cosmic time. This has been clearly demonstrated in the case of galaxy clusters in which powerful feedback from the central black hole is  preventing the hot intracluster gas from cooling catastrophically, thus reducing the expected star formation rates by orders of magnitude. >>

AA << present the first observational evidence for massive, runaway cooling occurring in the absence of supermassive black hole feedback in the high-redshift galaxy cluster SpARCS104922.6+564032.5 (..) The hot intracluster gas appears to be fueling a massive burst of star formation >>

<< Intracluster stars are therefore not only produced by tidal stripping and the disruption of cluster galaxies, but can also be produced by runaway cooling of hot intracluster gas at early times. Overall, these observations show the dramatic impact when supermassive black hole feedback fails to operate in clusters. They indicate that in the highest overdensities such as clusters and proto-clusters, runaway cooling may be a new and important mechanism for fueling massive bursts of star formation in the early universe. >>

J. Hlavacek-Larrondo, C.L. Rhea, et al. Evidence of runaway gas cooling in the absence of supermassive black hole feedback at the epoch of cluster formation. arXiv:2007.15660v1 [astro-ph.GA]. Jul 30, 2020.

https://arxiv.org/abs/2007.15660   

<< It reminds me of the old expression of 'when the cat's away, the mice will play,' (..) Here the cat, or black hole, is quiet and the mice, or stars, are very busy. >> Julie Hlavacek

Black hole fails to do its job. Chandra X-ray Center. Aug 3, 2020. 

https://phys.org/news/2020-08-black-hole-job.html   

# GST: how to harvest energy from impacting droplets

AA << designed an electrical generator that can harvest energy from impacting droplets and other sources of mechanical energy. (..) The electrical generator can be explained as being a permanently charged capacitor, also known as an electret. >>

They << managed to convert 11.8% of the mechanical energy of an impacting droplet into electrical energy, which is a significant improvement compared to the efficiency of similar devices. Furthermore, they demonstrated that the energy harvesting efficiency does not degrade after 100 days, requiring only a single 15 minute charging cycle before long-term application. >>

K.W. Wesselink. Generator developed for harvesting energy from droplets. 

University of Twente. Jul 8, 2020.

https://phys.org/news/2020-07-harvesting-energy-droplets.html

Hao Wu, Niels Mendel, et al. Charge Trapping‐Based Electricity Generator (CTEG): An Ultrarobust and High Efficiency Nanogenerator for Energy Harvesting from Water Droplets. Advanced Materials. doi: 10.1002/ adma.202001699. July 6, 2020.

https://onlinelibrary.wiley.com/doi/full/10.1002/adma.202001699  

Hao Wu, Niels Mendel, et al. Energy harvesting from drops impacting onto charged surfaces. Phys. Rev. Lett. Jun 25, 2020.

https://journals.aps.org/prl/accepted/ec07bYb0D261277cc08a6414c57b4ce4ab3e8da4f

Also

keyword 'drops' in Font:

https://flashontrack.blogspot.com/search?q=drops

# GST: apropos of the search of anomalies

<< I think in many respects, anomalies are a good driver of scientific creativity,  It’s like a paradox; you have to resolve it >> David Ireland

<< Anomalies force experimentalists to find ways of reducing systematic uncertainties, analyzing their data, and conducting more precise searches. Theorists, meanwhile, must grapple with anomalous results by building models that often assume new (..), >>

<< Particle physicists are faced with a growing list of “anomalies” — experimental results that conflict with the standard model but fail to overturn it for lack of sufficient evidence. >>

Dan Garisto. The Era of Anomalies. Physics 13, 79. May 14, 2020.

https://physics.aps.org/articles/v13/79

# gst: controlling particles with sound waves

<< Contactless manipulation of particles and cells using sound radiation forces that can be tuned and adjusted in real time has become important in various applications  (display tech, biomed sensors, imaging devices, diagnostic tools) >>

AA << use phononic crystals to tune sound fields in a microfluidic channel for controllable manipulation of microparticles and cells. An arbitrary stop-and-go motion of particles and cells along a predefined path in the channel is experimentally demonstrated. >>

Fei Li, Feiyan Cai, et al.  Phononic-Crystal-Enabled Dynamic Manipulation of Microparticles and Cells in an Acoustofluidic Channel.  Phys. Rev. Applied 13, 044077. Apr 30, 2020.

https://journals.aps.org/prapplied/abstract/10.1103/PhysRevApplied.13.044077

Controlling Particle Movements with Sound Waves. Physics 13, s58. Apr 30, 2020.

https://physics.aps.org/articles/v13/s58