Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Osiris REx: To learn in return and teach us each.
#34
(12-19-2018, 02:10 PM)Vianova Wrote: ...

On that cone formula -- redesigned at -- 0.3333333~ x Pi x radius x height,
that is correct,
but maybe it could be looked at from the perspective of:

sine 19.47122063  x Pi x radius x height.

If they want to attribute asteroid shapes to bi-cones,
then all this YORP spin-fu that they attribute to shape,
should probably have a fairly standard geometry in the cone apex.

Otherwise, we will see a plethora of dimensional cone shapes corresponding to different "spin" rates?

...

Recall:

Mnemonic devices are techniques a person can use to help them improve their ability to remember something. In other words, it's a memory technique to help your brain better encode and recall important information.

[/url]Memory and Mnemonic Devices - Psych Central


https://psychcentral.com/lib/memory-and-...c-devices/


Thatz the beauty of the variants of all the things three.

sum times the sine of the x's @~19.5 rides shot-gun.
Quote:On that cone formula -- redesigned at -- 0.3333333~
[Image: 45650183944_5b3089d49d_b.jpg]
Just an easy way to teach my grand-kid complex ideas as simple stuff.



So for the moment(um) just nevermind the cone or octahedrons and such.

In that previous article about gravity which is why asteroids aggregate etc.

Gravity is mathematically relatable to dynamics of subatomic particles
December 18, 2018 by Catherine Zandonella, [url=http://www.princeton.edu/main/]Princeton University

[Image: gravityismat.jpg]
Gravity, the force that brings baseballs back to Earth and governs the growth of black holes, is mathematically relatable to the peculiar antics of the subatomic particles that make up all the matter around us. Credit: J.F. Podevin

Gravity as the Fifth Dimension  Holycowsmile
Quote:Why don't they use TIME also as a variable?  Time is NEVER truly 'static', particles may be 'static' in 3 dimensions and in gravity, but can never be static in TIME.  TIME ALWAYS moves ... you had an article once that TIME may move BACKWARD.

Remember: "Why can't can't we remember the future...?" from Paul Kantner's The Light 1st of 5 song "theme" to Common Sense Party?
Quote:Recall:


Mnemonic devices are techniques a person can use to help them improve their ability to remember something. In other words, it's a memory technique to help your brain better encode and recall important information.

You found an article on "TIME CRYSTALS".  You cannot discard measurements of items in ANY 'theory' that you KNOW is there.
[Image: images?q=tbn:ANd9GcSMAIf9EoV6PrDhQ6k6ohl...fVsF8nu89A]


Let's use that tetrahedron instead of a cone.
[Image: hqdefault.jpg]
5-D eh?



Okay the first 3-D's are there in length width height right?
Time is the Base of the Tetrahedron. the 4th-D no matter which facet you choose if you were floating in 3-D space.
What if the Time Cone of the theoretical universe was a Time Tetrahedron instead?
An ever expanding and accelerating tetrahedron whose base was the Now.

The fifth dimension(Gravity would be the center of the base(Time Based)
and the 6th dimension would be the Apex/Origin point(Apex timeless)


Whew!  



[Image: regular-tetrahedron-and-face_0.jpg]

If the Point of Apex was Then and The Center of the Base was Now
you can already see the implicit 1/3 =~.333

Gravity is the fifth dimension of variants of the things three.

The Apex is the 6th
The Universe can be tetrahedrally summed up ???  
In a nutshell That fired some neurons and fried sum cells LilD sells snake-oil y'all.

Beer X's  Beer

I'll make a graph after a toke or two too. Heh.
Along the vines of the Vineyard.
With a forked tongue the snake singsss...
Reply
#35
Compare:
Quote:YORP spin-fufu [Image: whip.gif]


"Experiments like this are helping us better understand and control the quantum vacuum. It's what one might call 'the physics of empty space,' which upon closer examination seems to be not so empty after all," said John Gillaspy, the physics program officer who oversaw NSF funding of the research.

"Classically, the vacuum is really empty—it is, by definition, the absence of anything," said Gillaspy. "But quantum physics predicts that even the most empty space that one can imagine is filled with 'virtual' particles and fields, quantum fluctuations in pure emptiness that lead to subtle, but very real, effects that can be measured and even exploited to do things that would otherwise be impossible. The universe contains many complicated things, yet there are still unanswered questions about some of the simplest, most fundamental phenomena—this research may help us to find some of the answers."


The Casimir torque: Scientists measure previously unexamined tiny force

December 19, 2018, University of Maryland



[Image: 5c1a25ef84672.jpg]
Apparatus measuring the Casimir torque. Credit: Nature (2018). DOI: 10.1038/s41586-018-0777-8
Researchers from the University of Maryland have for the first time measured an effect that was predicted more than 40 years ago, called the Casimir torque.








When placed together in a vacuum less than the diameter of a bacterium (one micron) apart, two pieces of metal attract each other. This is called the Casimir effect. The Casimir torque—a related phenomenon that is caused by the same quantum electromagnetic effects that attract the materials—pushes the materials into a spin.spin-fufu [Image: whip.gif] Because it is such a tiny effect, the Casimir torque has been difficult to study. The research team, which includes members from UMD's departments of electrical and computer engineering and physics and Institute for Research in Electronics and Applied Physics, has built an apparatus to measure the decades-old prediction of this phenomenon and published their results in the December 20th issue of the journal Nature.



"This is an interesting situation where industry is using something because it works, but the mechanism is not well-understood," said Jeremy Munday, the leader of the research. "For LCD displays, for example, we know how to create twisted liquid crystals, but we don't really know why they twist. Our study proves that the Casimir torque is a crucial component of liquid crystal alignment. It is the first to quantify the contribution of the Casimir effect, but is not the first to prove that it contributes."



The device places a liquid crystal just tens of nanometers from a solid crystal. With a polarizing microscope, the researchers then observed how the liquid crystal twists to match the solid's crystalline axis.



The team used liquid crystals because they are very sensitive to external forces and can twist the light that passes through them. Under the microscope, each imaged pixel is either light or dark depending on how twisted the liquid crystal layer is. In the experiment, a faint change in the brightness of a liquid crystal layer allowed the research team to characterize the liquid crystal twist and the torque that caused it.



The Casimir effect could make nanoscale parts move and can be used to invent new nanoscale devices, such as actuators or motors.



"Think of any machine that requires a torque or twist to be transmitted: driveshafts, motors, etc.," said Munday. "The Casimir torque can do this on a nanoscale."







Knowing the amount of Casimir torque in a system can also help researchers understand the motions of nanoscale parts powered by the Casimir effect.



The team tested a few different types of solids to measure their Casimir torques, and found that each material has its own unique signature of Casimir torque.



The measurement devices were built in UMD's Fab Lab, a shared user facility and cleanroom housing tools to make nanoscale devices.



In the past, the researchers also made the first measurements of a repulsive Casimir force and a measurement of the Casimir force between two spheres. They have also made some predictions that could be confirmed if the current measurement technique can be refined; Munday reports they are testing other materials to control and tailor the torque.



Munday is an associate professor of electrical and computer engineering in UMD's A. James Clark School of Engineering, and his lab is housed in UMD's Institute for Research in Electronics and Applied Physics, which enables interdisciplinary research between its natural science and engineering colleges.



"Experiments like this are helping us better understand and control the quantum vacuum. It's what one might call 'the physics of empty space,' which upon closer examination seems to be not so empty after all," said John Gillaspy, the physics program officer who oversaw NSF funding of the research.



"Classically, the vacuum is really empty—it is, by definition, the absence of anything," said Gillaspy. "But quantum physics predicts that even the most empty space that one can imagine is filled with 'virtual' particles and fields, quantum fluctuations in pure emptiness that lead to subtle, but very real, effects that can be measured and even exploited to do things that would otherwise be impossible. The universe contains many complicated things, yet there are still unanswered questions about some of the simplest, most fundamental phenomena—this research may help us to find some of the answers."



 Explore further: Uncovering the interplay between two famous quantum effects



More information: David A. T. Somers et al, Measurement of the Casimir torque, Nature (2018). DOI: 10.1038/s41586-018-0777-8 



Journal reference: Nature 
Provided by: University of Maryland





Read more at: https://phys.org/news/2018-12-casimir-torque-scientists-previously-unexamined.html#jCp







In the new paper, the researchers propose levitating a nanoscale rotor using optical tweezers, which are formed by two counter-propagating polarized laser beams that cause the rotor to tightly align with the field polarization. When the beams are switched off, however, the tightly oriented rotor is predicted to quickly disperse into a superposition of all possible rotation statesspin-fufu [Image: whip.gif] as it falls toward the ground due to gravity.
 
Interestingly, the rotor is predicted to experience "quantum revivals" in which, at regular intervals in time, the collective interference of all of the rotation states leads to the re-emergence of the initial state that it occupied when it was aligned by the laser beams. The orientation can potentially be measured by illuminating the rotor with a weak probe laser, and the trapping laser could be switched back on to catch the rotor in this state before it reaches the ground.



Proposed test of quantum superposition measures 'quantum revivals'
December 19, 2018 by Lisa Zyga, Phys.org feature

[Image: proposedtest.jpg]
A nanoscale rotor (black rod) is levitated by two counter-propagating laser beams. When the beams are switched off, the quantum state of the rotor disperses into a superposition of all possible orientations, except at certain intervals of …more
Physicists have proposed an entirely new way to test the quantum superposition principle—the idea that a quantum object can exist in multiple states at the same time. The new test is based on examining the quantum rotation of a macroscopic object—specifically, a nanoscale rotor, which is considered macroscopic despite its tiny size.




Until now, most tests of quantum superposition have been based on linear, rather than rotational, motion. By examining rotational motion, the new testmay lead to applications such as quantum-enhanced torque sensing, and could provide insight into a variety of open questions, such as what causes the quantum wave function to collapse.

The physicists, led by Klaus Hornberger at the University of Duisburg-Essen, Germany, have published a paper on the proposed test in a recent issue of the New Journal of Physics.

Quantum superposition arises because, at the quantum scale, particles behave like waves. Similar to the way in which multiple waves can overlap each other to form a single new wave, quantum particles can exist in multiple overlapping states at the same time. If quantum superposition occurred in everyday life, we might observe phenomena like Schrödinger's cat, which is dead and alive at the same time until it is measured, forcing it to assume a single state.

In the new paper, the researchers propose levitating a nanoscale rotor using optical tweezers, which are formed by two counter-propagating polarized laser beams that cause the rotor to tightly align with the field polarization. When the beams are switched off, however, the tightly oriented rotor is predicted to quickly disperse into a superposition of all possible rotation states as it falls toward the ground due to gravity.

[Image: proposedtest.gif]
Animation showing how a nanorotor can disperse into a quantum superposition of rotation states, and then, due to quantum interference, undergo a revival, proving that a quantum state has existed. Credit: James Millen, King’s College London
Interestingly, the rotor is predicted to experience "quantum revivals" in which, at regular intervals in time, the collective interference of all of the rotation states leads to the re-emergence of the initial state that it occupied when it was aligned by the laser beams. The orientation can potentially be measured by illuminating the rotor with a weak probe laser, and the trapping laser could be switched back on to catch the rotor in this state before it reaches the ground.



So far, orientational quantum revivals have been observed only in gases of diatomic molecules. As the nanorods consist of at least 10,000 atoms, they are much larger than the diatomic molecules, allowing for quantum mechanics to be tested in an uncharted regime.

The physicists expect that it will be possible to observe quantum revivals of the nanorods using existing technology, such as by using a carbon nanotube as the rotor. If so, the observation would represent a new macroscopic test of quantum superposition.

"By observing the quantum revivals, we hope to confirm quantum mechanics at an unprecedented mass and complexity scale, thereby exploring the quantum-to-classical borderline," Hornberger told Phys.org.

In the future, coauthor James Millen, now at King's College London, plans to perform the proposed experiment to detect macroscopic quantum revivals.

"Testing whether quantum physics breaks down at a high mass is an exciting, yet daunting, challenge," Millen said. "We may have to develop entirely new technologies to isolate nanoscale particles, or even perform experiments in space. However, this experiment which we propose opens up an entirely new route to probing enigmatic quantum effects, in a way which I firmly believe is feasible with today's technology. Furthermore, we will be able to harness this physics to develop useful devices of unprecedented sensitivity."

Explore further: How Einstein's equivalence principle extends to the quantum world

More information: Benjamin A. Stickler et al. "Probing macroscopic quantum superpositions with nanorotors." New Journal of Physics. DOI: 10.1088/1367-2630/aaece4 

Journal reference: New Journal of Physics


Read more at: https://phys.org/news/2018-12-quantum-su...s.html#jCp


EA States:
The Universe is a spinning tetrahedron in a superposition of all states.

spin-fufu [Image: whip.gif]

I put this spin on it...

doubled is as trebled was
[Image: depalma+spinning+ball+exp.JPG]
If a tetrahedron spins on an axis from the apex point to the center of the base the Trace would be a cone but would require time to route out from the fabric of space a cone shape like a tool-bit and there you have tour vortex from the basal 3 vertex.
If spin is measured as a superimposition of all states then a Tetrahedron can indeed be a solid/non-solid cone if an Axis is prefered.

A tetrahedron with no axis that spins around itz core central point superimposes a sphere that itza circumscribed itself.
Along the vines of the Vineyard.
With a forked tongue the snake singsss...
Reply
#36
...

Roman Tcachenko animations 
https://twitter.com/i/status/1072841352017313794
Flying Over Asteroid Bennu 
This 3D visualization is based on my preliminary 3D shape model of Bennu


Bennu 3D rotation
https://www.youtube.com/watch?v=V_DVoetIHEw



...
Reply
#37
[Image: 121418_jl_bennu-shape_feat.jpg]


2-D cross-section of Bennu / Ruyugu 2 too?
[Image: e127_3_medium.png] doubled is as trebled was
Same shape as the twin asteroids

Twin ass-rhoids  Arrow

We'll now call Bennu "Stu"

...and Ryugu's called "Stu2"



Just for improv's sake.

Quote:Posted by rhw007 - Wednesday, December 19th, 2018, 04:46 am
Why don't they use TIME also as a variable?  Time is NEVER truly 'static', particles may be 'static' in 3 dimensions and in gravity, but can never be static in TIME.  TIME ALWAYS moves ... you had an article once that TIME may move BACKWARD.

Remember: "Why can't can't we remember the future...?" from Paul Kantner's The Light 1st of 5 song "theme" to Common Sense Party?

Quote:Asking what happened before the Big Bang is a meaningless question in general relativity, because space-time ends, and there is no before. 

You found an article on "TIME CRYSTALS".  You cannot discard measurements of items in ANY 'theory' that you KNOW is there.

To do that, you are doing no better than Never A Straight Answer/ Just Pricks Lapping.

Also gravity is also a variable, not a constant.  We may think it is a constant 32/feet/ second on Earth, at Sea Level, what is the gravity of Voyagers 1 & 2 by the Sun ?  The same 32/feet/sec?   [Image: naughty.gif] 

When I had an A in Calculus before wife had stroke, doing several equations at once was a breeze.  Not so anymore. But I haven't lost some BASIC 'presumptions' that one must throw away to free up the blank holes in the mind to awaken and light new insight into the brains neurons; otherwise...your RAM never gets updates.

Bob.... 

You asked and the improvisphere thus provides.  Arrow


Beyond the black hole singularity
December 20, 2018 by Sam Sholtis, Pennsylvania State University

[Image: beyondthebla.jpg]
Artist representation of a black hole. The bottom half of the image depicts the black hole which, according to general relativity, traps everything including light. Effects based on loop quantum gravity, a theory that extends Einstein's …more
Our first glimpses into the physics that exist near the center of a black hole are being made possible using "loop quantum gravity"—a theory that uses quantum mechanics to extend gravitational physics beyond Einstein's theory of general relativity. Loop quantum gravity, originated at Penn State and subsequently developed by a large number of scientists worldwide, is opening up a new paradigm in modern physics. The theory has emerged as a leading candidate to analyze extreme cosmological and astrophysical phenomena in parts of the universe, like black holes, where the equations of general relativity cease to be useful.




Previous work in loop quantum gravity that was highly influential in the field analyzed the quantum nature of the Big Bang, and now two new papers by Abhay Ashtekar and Javier Olmedo at Penn State and Parampreet Singh at Louisiana State University extend those results to black hole interiors. The papers appear as "Editors' suggestions" in the journals Physical Review Letters and Physical Review on December 10, 2018 and were also highlighted in a Viewpoint article in the journal Physics.

"The best theory of gravity that we have today is general relativity, but it has limitations," said Ashtekar, Evan Pugh Professor of Physics, holder of the Eberly Family Chair in Physics, and director of the Penn State Institute for Gravitation and the Cosmos. "For example, general relativitypredicts that there are places in the universe where gravity becomes infinite and space-time simply ends. We refer to these places as 'singularities.' But even Einstein agreed that this limitation of general relativity results from the fact that it ignores quantum mechanics."

At the center of a black hole the gravity is so strong that, according to general relativity, space-time becomes so extremely curved that ultimately the curvature becomes infinite. This results in space-time having a jagged edge, beyond which physics no longer exists—the singularity. Another example of a singularity is the Big Bang. Asking what happened before the Big Bang is a meaningless question in general relativity, because space-time ends, and there is no before.  But modifications to Einstein's equations that incorporated quantum mechanics through loop quantum gravity allowed researchers to extend physics beyond the Big Bang and make new predictions. The two recent papers have accomplished the same thing for the black hole singularity.

"The basis of loop quantum gravity is Einstein's discovery that the geometry of space-time is not just a stage on which cosmological events are acted out, but it is itself a physical entity that can be bent," said Ashtekar. "As a physical entity the geometry of space-time is made up of some fundamental units, just as matter is made up of atoms. These units of geometry—called 'quantum excitations'—are orders of magnitude smaller than we can detect with today's technology, but we have precise quantum equations that predict their behavior, and one of the best places to look for their effects is at the center of a black hole." According to general relativity, at the center of a black hole gravity becomes infinite so everything that goes in, including the information needed for physical calculations, is lost. This leads to the celebrated 'information paradox' that theoretical physicists have been grappling with for over 40 years. However, the quantum corrections of loop quantum gravity allow for a repulsive force that can overwhelm even the strongest pull of classical gravity and therefore physics can continue to exist. This opens an avenue to show in detail that there is no loss of information at the center of a blackhole, which the researchers are now pursuing.

Interestingly, even though loop quantum gravity continues to work where general relativity breaks down—black hole singularities, the Big Bang—its predictions match those of general relativity quite precisely under less extreme circumstances away from the singularity. "It is highly non-trivial to achieve both," said Singh, associate professor of physics at Louisiana State. "Indeed, a number of investigators have explored the quantum nature of the black hole singularity over the past decade, but either the singularity prevailed or the mechanisms that resolved it unleashed unnatural effects. Our new work is free of all such limitations."

Explore further: Theorists apply loop quantum gravity theory to black hole

More information: Abhay Ashtekar et al, Quantum Transfiguration of Kruskal Black Holes, Physical Review Letters (2018). DOI: 10.1103/PhysRevLett.121.241301 

Journal reference: Physical Review Letters
Provided by: Pennsylvania State University



Read more at: https://phys.org/news/2018-12-black-hole-singularity.html#jCp







Viewpoint: Black Hole Evolution Traced Out with Loop Quantum Gravity
  • Carlo Rovelli, Center of Theoretical Physics, CNRS, Aix-Marseille University and Toulon University, Marseille, France
December 10, 2018• Physics 11, 127
Loop quantum gravity—a theory that extends general relativity by quantizing spacetime—predicts that black holes evolve into white holes.
[Image: e127_2_medium.png][Image: icon-expand.svg]
F. Vidotto/University of the Basque Country

Figure 1: Artist rendering of the black-to-white-hole transition. Using loop quantum gravity, Ashtekar, Olmedo, and Singh predict that black holes evolve into white holes.

Black holes are remarkable entities. On the one hand, they have now become familiar astrophysical objects that have been observed in large numbers and in many ways: we have evidence of stellar-mass holes dancing around with a companion star, of gigantic holes at the center of galaxies pulling in spiraling disks of matter, and of black hole pairs merging in a spray of gravitational waves. All of this is beautifully accounted for by Einstein’s century-old theory of general relativity. Yet, on the other hand, black holes remain highly mysterious. We see matter falling into them, but we are in the dark about what happens to this matter when it reaches the center of the hole.
Abhay Ashtekar and Javier Olmedo at Pennsylvania State University in University Park and Parampreet Singh at Louisiana State University, Baton Rouge, have taken a step toward answering this question [1]. They have shown that loop quantum gravity—a candidate theory for providing a quantum-mechanical description of gravity—predicts that spacetime continues across the center of the hole into a new region that exists in the future and has the geometry of the interior of a white hole. A white hole is the time-reversed image of a black hole: in it, matter can only move outwards. The passage “across the center” into a future region is counterintuitive; it is possible thanks to the strong distortion of the spacetime geometry inside the hole that is allowed by general relativity. This result supports a hypothesis under investigation by numerous research groups: the future of all black holes may be to convert into a real white hole, from which the matter that has fallen inside can bounce out. However, existing theories have not been able to fully show a way for this bounce to happen. That loop quantum gravity manages to do it is an indication that this theory has ripened enough to tackle real-world situations.
The reason why we are in the dark about aspects of black hole physics is that quantum phenomena dominate at the center and in the future of these objects. Classical general relativity predicts that a black hole lives forever and that its center is a “singularity” where space and time end. These predictions are not realistic because they disregard quantum effects. To tackle these effects we need a quantum theory of gravity. We don’t yet have consensus on such a theory, but we have candidates, some of which are now reaching the point of allowing actual calculations on the quantum behavior of black holes. Loop quantum gravity, which has a clean conceptual structure and a well-defined mathematical formulation based on representing the fabric of space as a spin network that evolves in time, is one such theory.
During the last few years, a number of research groups have applied loop theory to explore the evolution of black holes. These efforts are building a compelling picture based on a black-to-white-hole transition scenario (Fig. 1), which can be summarized as follows [2]. At the center of the black hole, space and time do not end in a singularity, but continue across a short transition region where the Einstein equations are violated by quantum effects. From this region, space and time emerge with the structure of a white hole interior, a possibility suggested in the 1930s by physicist John Lighton Synge [3]. As the hole’s center evolves, its external surface, or “horizon,” slowly shrinks because of the emission of radiation—a phenomenon first described by Stephen Hawking. This shrinkage continues until the horizon reaches the Planck size (the characteristic scale of quantum gravity) or earlier [45], at which point a quantum transition (“quantum tunneling”) happens at the horizon, turning it into the horizon of a white hole (Fig. 2). Thanks to the peculiar distorted relativistic geometry, the white hole interior born at the center joins the white horizon, completing the formation of the white hole.
[Image: e127_3_medium.png][Image: icon-expand.svg]
C. Rovelli/Aix-Marseille University; adapted by APS/Alan Stonebraker

Figure 2: Diagram representing the spacetime evolution of a black hole into a white hole via a quantum transition. The vertical axis represents time; the horizontal axis represents distance from the center.

Loosely speaking, the full phenomenon is analogous to the bouncing of a ball. A ball falls to the ground, bounces, and then moves up. The upward motion after the bounce is the time-reversed version of the falling ball. Similarly, a black hole “bounces” and emerges as its time-reversed version—a white hole. Collapsing matter does not disappear at the center: it bounces up through the white hole. Energy and information that fell into the black hole emerge from the white hole. The configuration where the compression is maximal, which separates the black hole from the white hole, is called a “Planck star.” Because of the huge time distortion allowed by relativity, the time for the process to happen can be short (microseconds) when measured from inside the hole but long (billions of years) when measured from the outside. Black holes might be bouncing stars seen in extreme slow motion.
This is a compelling picture because it removes the singularity at a black hole’s center and resolves the paradox of the apparent disappearance of energy and information into a black hole. Until now, this black-to-white-hole picture was not derived from an actual quantum theory of gravity; it was just conjectured—and implemented with ad hocmodifications to Einstein’s general relativity equations. Ashtekar, Olmedo, and Singh have shown that a crucial ingredient of this scenario, the transition at the center, follows from a genuine quantum gravity theory, namely, loop theory. The result was obtained through an approximation of the full loop-quantum-gravity equations [6]—similar to the one employed in previous work aimed at resolving the big bang singularity [7].
It is important to note that the Ashtekar-Olmedo-Singh model addresses only the transition at the center of the hole. To complete the picture, we also need the calculation of the tunneling at the horizon [5]. Preliminary steps in this direction have been taken, but the problem is open. Its solution would lead to a complete understanding of the quantum physics of black holes.
It is not implausible that empirical observations could support this scenario. Models suggest that several observed astrophysical phenomena could be related to the black-to-white-hole transition [8]. Among these are fast radio bursts (FRBs) and certain high-energy cosmic rays. Both could be produced by matter and photons that were trapped in black holes produced in the early Universe and liberated by the black-to-white-hole transition. For the moment, however, the astrophysical data are insufficient to determine whether the statistical properties of observed FRBs and cosmic rays confirm this hypothesis [8]. Another intriguing possibility is that small holes produced by the black-to-white-hole transition may be stable: in which case, these “remnants” could be a component of dark matter [9].
We are only beginning to understand the quantum physics of black holes, but in this still speculative field, the Ashtekar-Olmedo-Singh result gives us a welcome fixed point: loop gravity predicts that the interior of a black hole continues into a white hole. The importance of any progress in this field goes beyond understanding black holes. The center of a black hole is where our current theory of spacetime, as given by Einstein’s general relativity, fails. Understanding the physics of this region would mean understanding quantum space and quantum time.
This research is published in Physical Review Letters and Physical Review D.
References
  1. A. Ashtekar, J. Olmedo, and P. Singh, “Quantum transfiguration of Kruskal black holes,” Phys. Rev. Lett. 121, 241301 (2018); “Quantum extension of the Kruskal spacetime,” Phys. Rev. D 98, 126003 (2018).

  2. E. Bianchi, M. Christodoulou, F. D’Ambrosio, H. M. Haggard, and C. Rovelli, “White holes as remnants: A surprising scenario for the end of a black hole,” Class. Quant. Grav. 35, 225003 (2018).

  3. J. L. Synge, “The gravitational field of a particle,” Proc. Roy. Irish Acad. A 53, 83 (1950).

  4. C. Rovelli and F. Vidotto, “Planck stars,” Int. J. Mod. Phys. D 23, 1442026 (2014).

  5. H. M. Haggard and C. Rovelli, “Quantum-gravity effects outside the horizon spark black to white hole tunneling,” Phys. Rev. D 92, 104020 (2015).

  6. L. Modesto, “Black hole interior from loop quantum gravity,” Adv. High Energy Phys. 2008, 459290 (2008).

  7. I. Agullo and P. Singh, “Loop quantum cosmology: A brief review,” Loop Quantum Gravity, 100 Years of General Relativity Vol. 4, edited by A. Ashtekar and J. Pullin (World Scientific, Singapore, 2017)[Amazon][WorldCat].

  8. A. Barrau, B. Bolliet, F. Vidotto, and C. Weimer, “Phenomenology of bouncing black holes in quantum gravity: A closer look,” J. Cosmol. Astropart. Phys. 2016, 022 (2016); A. Barrau, K. Martineau, and F. Moulin, “Status report on the phenomenology of black holes in loop quantum gravity: Evaporation, tunneling to white holes, dark matter and gravitational waves,” Universe 4, 102 (2018).

  9. C. Rovelli and F. Vidotto, “Small black/white hole stability and dark matter,” Universe 4, 127 (2018).
Along the vines of the Vineyard.
With a forked tongue the snake singsss...
Reply
#38
Well, as I stated I used to do Calculus before my wife's stroke there is no way to get back up to speed on that.  However, Has a 'WHITE HOLE" ever been seen?

Never heard of one, so my other notion was that each black hole could be an entry to a NEW Universe than the one that the Black hole resides.  Since most of the matter and energy in our Universe is DARK Matter and Dark Energy, which when pushed it actually attracts to what pushed it. From current understanding as I know it.

If wrong please forgive me.  If the Black Hole is a portal to a new Universe with a reverse in Dark Matter and Dark Energy to one of Light Matter and Light Energy, if a spaceship had a 'map' of all KNOWN Black Holes in our Universe we could transport back through a WHITE HOLE back into OUR Universe...if there were White Holes in the bottom of Black Holes.

Or, Dark Holes could simply be more "Big Bangs" starting new Universes.   Who knows what the 'Creator' created and why and when?

We keep getting so many 'timelines' wrong, making so many presumptions, so many new 'theories' that facts aren't as flat as they should be.  We might only know after final death when our souls FINALLY are free from the body.  I had 7 actual trips, close to death, 8 months coming close to that same plane of existence; I won't KNOW until I finally leave for good.  If I could come back in some manner I might try, then again, I may be unable to do much of anything.

It seems that even physics article is also generating 'possibility' after equation after equation, the answer continues to elude us.

Thank you for the response EA Worship

Bob... Ninja Assimilated
"The Light" - Jefferson Starship-Windows of Heaven Album
I'm an Earthling with a Martian Soul wanting to go Home.   
You have to turn your own lightbulb on. ©stevo25 & rhw007
Reply
#39
...
Bennu in a number of still images,
number 8 is my favorite.

https://drive.google.com/file/d/1nx4TPd0...LVk2BfIkms

...
Reply
#40
(12-21-2018, 01:43 AM)rhw007 Wrote: Thank you for the response EA Worship

Bob... Ninja Assimilated

feedback-loops are pluralities and therefore superimposed  and thus superimprovised.
Recall:
Arrow To learn in return and teach us each.


Quote:Posted by EA - Friday, December 21st, 2018, 12:17 am

for improv's sake.


Bob.... 
[size=undefined]

You asked and the improvisphere thus provides.  [Image: arrow.png] [/size]


Same  Sheep   Difference
    feedback                                      loop
[Image: 121418_jl_bennu-shape_feat.jpg]Sss.............................Stu    [Image: images?q=tbn:ANd9GcSpSZT-GvZ-766uUV6s3qu..._v3T_aOnKA]Stu2

Stupor-imposed like they were  exo/in-situ/see too ipso@ http://thehiddenmission.com/forum/index.php
Along the vines of the Vineyard.
With a forked tongue the snake singsss...
Reply
#41
Quote:Stupor-imposed like...



Frontier of planetary science
Ultima Thule is named for a mythical, far-northern island in medieval literature and cartography, according to NASA.
Project scientist Hal Weaver of the Johns Hopkins Applied Physics Laboratory said humans didn't even know the Kuiper Belt—a vast ring of relics from the formation days of the solar system—existed until the 1990s.
"This is the frontier of planetary science," said Weaver.
"We finally have reached the outskirts of the solar system, these things that have been there since the beginning and have hardly changed—we think. We will find out."
Another NASA spacecraft, OSIRIS-REx, also set a new record on Monday by entering orbit around the asteroid Bennu, LilD the smallest cosmic object—about 1,600 feet (500 meters) in diameter—ever circled by a spacecraft.
NASA said the orbit some 70 million miles (110 million kilometers) away marks "a leap for humankind" because no spacecraft has ever "circled so close to such a small space object—one with barely enough gravity to keep a vehicle in a stable orbit."
The twin planetary feats coincided with the 50th anniversary of the first time humans ever explored another world, when US astronauts orbited the Moon aboard Apollo 8 in December, 1968.
"As you celebrate New Year's Day, cast an eye upward and think for a moment about the amazing things our country and our species can do when we set our minds to it," Stern wrote in the New York Times on Monday.


Read more at: https://phys.org/news/2019-01-nasa-year-historic-flyby-faraway.html#jCp
Along the vines of the Vineyard.
With a forked tongue the snake singsss...
Reply
#42
OSIRIS-REx finds rugged terrain on asteroid Bennu
January 31, 2019 Stephen Clark
[img=788x0]https://mk0spaceflightnoa02a.kinstacdn.com/wp-content/uploads/2019/01/NavCamJan17Images.jpg[/img]NASA’s OSIRIS-REx spacecraft’s navigation camera captured this image of asteroid Bennu on Jan. 17 from a distance of approximately 1 mile (1.6 kilometers). The large boulder in partial shadow at the lower right of the frame is about 165 feet (50 meters) across. Credit: NASA/Goddard/University of Arizona/Lockheed Martin
Some time next year, NASA’s OSIRIS-REx spacecraft will descend to the boulder-strewn surface of asteroid Bennu, reach out with a robotic arm, and fetch a sample for return to Earth, but an initial survey of the space rock millions of miles from Earth suggests the robotic mission may have few suitable targets for the touch-and-go maneuver.

OSIRIS-REx is still in the early weeks of its stay at asteroid Bennu, a roughly 1,640-foot-wide (500-meter) object that oscillates inside and outside of Earth’s orbit on each trip around the sun. Bennu’s proximity to Earth, which makes it an impact risk to the planet in the distant future, allowed ground-based radars to scan the asteroid in detail, revealing its size and shape before OSIRIS-REx’s launch in 2016.
The radar observations made by stations at Arecibo, Puerto Rico, and Goldstone, California, did a “phenomenal job of predicting the shape and topography of the asteroid for us,” said Dante Lauretta, principal investigator for the $1 billion Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer mission at the University of Arizona, Tucson.
On its approach to the asteroid last year, OSIRIS-REx showed Bennu is shaped like diamond, or a spinning top, just as the radar observations suggested.
“It’s really good news that we got it so right, and that all our mission design plans are valid as we move forward,” Lauretta said Wednesday at a meeting of NASA’s Small Bodies Assessment Group, a community of scientists with research interests in asteroids, comets and other small objects in the solar system.
“We do have the expected, so-called ‘spinning top’ shape, which seems to be characteristic of a subset of the near-Earth asteroid population,” Lauretta said.
“One of the reasons we think it’s top-shaped is because it’s been accelerated by thermal pressures to sort of spin up,” said Olivier Barnouin, a co-investigator on the OSIRIS-REx mission from the Johns Hopkins University Applied Physics Laboratory. “You can imagine if you take a top and start spinning up, if you have little rocks on it, things might go flying off.”
OSIRIS-REx’s cameras searched for evidence of moons or debris around Bennu late last year.
“We can confirm, to this point, that we have not identified any rocks that are flying around, and that there’s no risk to the spacecraft, which actually I think is kind of remarkable because this place is very dynamic,” Barnouin said in a Dec. 31 presentation of the mission’s preliminary findings at Bennu.
But Bennu did present some surprises to scientists, such as its jagged, craggy terrain covered with a collection of boulders, rock piles, craters and ridges.
“Some of the things that jump out at us right away from the asteroid’s surface are the large boulders,” Lauretta said Wednesday. “We are a looking at a pretty rough and rugged surface, more so than we expected.”
The first detailed images from OSIRIS-REx suggest Bennu exhibits the scars from collisions with other objects in the solar system, perhaps when Bennu orbited in the main asteroid belt between the orbits of Mars and Jupiter. The basins include up to a dozen large impact craters that measure up to 500 feet (150 meters) in diameter, according to Lauretta.
“We’re thinking that the asteroid surface’s cratering age may be older than we expected, and may record its collisional history in the main asteroid belt,” he said.
Scientists believe the asteroid’s visible surface may be between 100 million and 1 billion years old, and Lauretta says Bennu is likely a “rubble pile” asteroid, made by the merging of several distinct objects. With the data already returned by OSIRIS-REx, scientists have calculated Bennu has a bulk density just 20 percent higher than that of water, and a bit less than that of Jupiter.
Officials marked OSIRIS-REx’s arrival at Bennu on Dec. 3, when the spacecraft flew over the asteroid’s north pole. Subsequent passes over both poles and the equator allowed scientists to calculate the asteroid’s mass, a crucial parameter for planning the probe’s future trajectories.
[img=788x0]https://mk0spaceflightnoa02a.kinstacdn.com/wp-content/uploads/2016/09/1472585684039.jpg[/img]An artist’s concept of OSIRIS-REx at Bennu, with its sample collection arm extended. Credit: Lockheed Martin
OSIRIS-REx is currently in the mission’s “Orbital A” phase, following a maneuver Dec. 31 that directed the spacecraft into a slow-speed loop around Bennu that ranges between 1 mile and 1.3 miles (1.6 to 2.1 kilometers) from the asteroid. Due to Bennu’s weak gravity field, thousands of times weaker than that of Earth, OSIRIS-REx travels at a speed of just one-tenth of a mile per hour, or 5 centimeters per second, relative to the asteroid.
The orbital velocity of satellites circling the Earth can be as high as 17,500 mph (7.8 kilometers per second).
OSIRIS-REx has set records, becoming the first mission to orbit an object as small as Bennu, and as the closest any spacecraft has orbited to any planetary body.
The craft’s navigation team on Earth is plotting the location of landmarks and other prominent features on the asteroid’s surface. Beginning next month, OSIRIS-REx will fly on station-to-station trajectories around the asteroid, pulsing its thrusters to cover Bennu globally and periodically move to closer and farther distances.
“The orbit phase is not really a science campaign phase,” Lauretta said. “It’s primarily there for the navigation team to transition from using star fields to landmarks on the asteroid surface. That transition is going very well, and are achieving navigation accuracies that are required for us to depart orbit in about four weeks and begin the detailed survey campaign of the mission.”
When the solar system formed more than 4.5 billion years ago, chunks of rock and ice collided as they circled the sun like the balls on a billiard table, eventually building up planets. The leftovers became asteroids and comets, and scientists believe Bennu still harbors the basic carbon-bearing organic molecules that were present in the early solar solar system, the stuff that may have helped seed life.
The spacecraft carries three cameras — one for long-range viewing, a color camera for mapping, and another imager to take pictures as OSIRIS-REx collects samples from the asteroid’s surface. The rest of OSIRIS-REx’s suite of science instruments includes a thermal emission spectrometer to detect heat coming from the asteroid, a visible infrared spectrometer to locate minerals and organic materials, a laser altimeter provided by the Canadian Space Agency to create topographic maps, and a student-built X-ray spectrometer to identify individual chemical elements present on the asteroid.
Data gathered by thermal emission and visible infrared spectrometer instruments — OTES and OVIRS — indicates clay minerals on the asteroid’s surface contain hydroxyl molecules with oxygen and hydrogen molecules bonded together. This finding suggests Bennu’s surface was once in contact with water, likely when the asteroid was part of a much larger parent body that was smashed to bits in a collision in the chaotic early solar system.
One prominent feature of Bennu’s landscape is a large boulder protruding from the surface near the south pole. While ground-based radar images suggested the boulder to be at least 33 feet, or 10 meters, in height, OSIRIS-REx imagery indicates is closer to 164 feet, or 50 meters, tall with a width of approximately 180 feet, or 55 meters, according to NASA.
On approach to Bennu, ground controllers at Lockheed Martin in Denver — where OSIRIS-REx was built — unlatched the probe’s robotic arm from its launch restraint for the first time. Over several days, the ground team commanded the arm to bend its joints and jettison a launch cover over the sample collection mechanism, which will release compressed air during a touch-and-go maneuver to force gravel and surface material into an on-board chamber for the journey back to Earth.
[img=788x0]https://mk0spaceflightnoa02a.kinstacdn.com/wp-content/uploads/2018/12/bennuasteroid.jpg[/img]This mosaic image of asteroid Bennu is composed of 12 PolyCam images collected on Dec. 2 by the OSIRIS-REx spacecraft from a range of 15 miles (24 km). One of the darkest features on Bennu is visible at lower left. Credits: NASA/Goddard/University of Arizona
One of the darkest features spotted so far on Bennu appears to be rich in magnetite and iron oxide, Lauretta said, based on early spectral measurements from OSIRIS-REx’s instruments. Scientists are intrigued by the darker regions of the asteroid because they are expected to contain more carbon, the scientific pay dirt for the sample return mission.
But officials will evaluate where OSIRIS-REx can safely reach the surface in the coming months, with the tough-and-go descent currently scheduled for July 4, 2020. That can be pushed back a few months, if necessary, before the spacecraft must depart Bennu in March 2021 to reach Earth in September 2023.
“The OSIRIS-REx mission’s sample site selection campaign starts next month, which is when we will start receiving science data at the resolution needed to make informed assessments about the safety of various regions on Bennu,” Lauretta said in a written response Thursday to questions from Spaceflight Now.
“We’re thinking about sampling the surface … and the craters are starting to look as possibly good candidates because they’re fairly smooth in structure, as far as we can tell at this point in the mission,” Barnouin said.


https://spaceflightnow.com/2019/01/31/os...oid-bennu/
Along the vines of the Vineyard.
With a forked tongue the snake singsss...
Reply
#43
...
That was a good catch up on info and data in that article.
this caught my eye:


Quote:While ground-based radar images suggested the boulder to be at least ---> 33 feet, 
or 10 meters, in height, 
OSIRIS-REx imagery indicates is closer to  --->  164 feet, 
or 50 meters tall, 
with a width of approximately 180 feet, or 55 meters, 
according to NASA.


That is an enormous differential at 5 times the height when imaged by the probe!
Tells you a lot about "ground based" science conclusions,
on objects out in space, 
to include all their theories offered on that ground based science of those solar system objects.

...
Reply
#44
Asteroid Bennu, target of NASA's sample return mission, is rotating faster over time
March 12, 2019, American Geophysical Union

[Image: asteroidbenn.jpg]
This mosaic image of asteroid Bennu is composed of 12 PolyCam images collected on Dec. 2 by the OSIRIS-REx spacecraft from a range of 15 miles (24 km). The image was obtained at a 50° phase angle between the spacecraft, asteroid and the …more
In late 2018, the Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer (OSIRIS-REx) spacecraft arrived at Bennu, the asteroid it will be studying and sampling over the next several years.




Now, new research in the AGU journal Geophysical Research Lettersshows Bennu is spinning faster over time—an observation that will help scientists understand the evolution of asteroids, their potential threat to Earth and if they could be mined for resources.

Bennu is 110 million kilometers (70 million miles) away from Earth. As it moves through space at about 101,000 kilometers per hour (63,000 miles per hour), it also spins, completing a full rotation every 4.3 hours.

The new research finds the asteroid's rotation is speeding up by about 1 second per century. In other words, Bennu's rotation period is getting shorter by about 1 second every 100 years.

While the increase in rotation might not seem like much, over a long period of time it can translate into dramatic changes in the space rock. 

Quote:EA States:
The Universe is a spinning tetrahedron in a superposition of all states.

spin-fufu [Image: whip.gif]

I put this spin on it...

doubled is as trebled was

As the asteroid spins faster and faster over millions of years, it could lose pieces of itself or blow itself apart, according to the study's authors.

Detecting the increase in rotation helps scientists understand the types of changes that could have happened on Bennu, like landslides or other long-term changes, that the OSIRIS-REx mission will look for.

"As it speeds up, things ought to change, and so we're going to be looking for those things and detecting this speed up gives us some clues as to the kinds of things we should be looking for," said Mike Nolan, a senior research scientist at the Lunar and Planetary Laboratory at the University of Arizona in Tucson, who is the lead author of the new paper and the head of the OSIRIS-REx mission's science team. "We should be looking for evidence that something was different in the fairly recent past and it's conceivable things may be changing as we go."

The OSIRIS-REx mission is scheduled to bring a sample of Bennu to Earth in 2023. Understanding Bennu's rotational change could help scientists figure out what asteroids can tell us about the origin of the solar system, how likely it is for asteroids to pose a threat to humans and if they could be mined for resources.

"If you want to do any of those things, you need to know what is affecting it," Nolan said.



[Image: asteroidbenn.gif]
This series of MapCam images was taken over the course of about four hours and 19 minutes on Dec. 4, 2018, as OSIRIS-REx made its first pass over Bennu’s north pole. The images were captured as the spacecraft was inbound toward Bennu, shortly before its closest approach of the asteroid’s pole. As the asteroid rotates and grows larger in the field of view, the range to the center of Bennu shrinks from about 7.1 to 5.8 miles (11.4 to 9.3 km). This first pass was one of five flyovers of Bennu’s poles and equator that OSIRIS-REx conducted during its Preliminary Survey of the asteroid. Credit: NASA/Goddard/University of Arizona
Detecting a change

In order to understand Bennu's rotation, scientists studied data of the asteroid taken from Earth in 1999 and 2005, along with data taken by the Hubble Space Telescope in 2012. It was when they looked at the Hubble data that they noticed the rotation speed of the asteroid in 2012 didn't quite match their predictions based on the earlier data.

"You couldn't make all three of them fit quite right," Nolan said. "That was when we came up with this idea that it had to be accelerating."

The idea that the rotation of asteroids could speed up over time was first predicted around 2000 and first detected in 2007, according to Nolan. To date, this acceleration has only been detected in a handful of asteroids, he said.

The change in Bennu's rotation could be due to a change in its shape. Similar to how ice skaters speed up as they pull in their arms, an asteroid could speed up as it loses material.

Nolan and his co-authors suggest the reason for the increase in Bennu's rotation is more likely due to a phenomenon known the YORP effect. Sunlight hitting the asteroid is reflected back into space. The change in the direction of the light coming in and going out pushes on the asteroid and can cause it to spin faster or slower, depending on its shape and rotation.

The OSIRIS-REx mission will determine Bennu's rotation rate independently this year, which will help scientists nail down the reason for the increase in rotation. Since spacecraft will never visit the vast majority of asteroids, the measurements will also help scientists learn how well ground-based measurements are able to understand these far-away objects.

"By testing these predictions in a few cases, we will significantly improve our confidence in predictions made for other objects," the study's authors write.

The measurement of Bennu's acceleration rate combined with the arrival of OSIRIS-REx at the asteroid gives scientists a great opportunity to validate the new study's results and test theories about the YORP effect, said Desiree Cotto-Figueroa, an assistant professor of physics and electronics at the University of Puerto Rico at Humacao, who was not involved in the new study.

"This is a great opportunity, in general, having this measurement and having the spacecraft OSIRIS-REx there observing this asteroid to help us better understand this effect, which is a dominant mechanism in the evolution of asteroids," she said.

[Image: 1x1.gif] Explore further: Video: Planetary scientist talks about her work with NASA studying asteroid Bennu

More information: M. C. Nolan et al, Detection of Rotational Acceleration of Bennu Using HST Light Curve Observations, Geophysical Research Letters (2019). DOI: 10.1029/2018GL080658 

Journal reference: Geophysical Research Letters [Image: img-dot.gif][Image: img-dot.gif]
Provided by: American Geophysical Union



Read more at: https://phys.org/news/2019-03-asteroid-bennu-nasa-sample-mission.html#jCp
Along the vines of the Vineyard.
With a forked tongue the snake singsss...
Reply
#45
Gee ya think this tin can with kilos of equipment now in IT"S OWN orbit around the Sun wouldn't ya think the Probe ITSELF is causing the difference from now on?

Doh

If not, then you better hurry up on that "sample return" while you STILL have a non-rotating curve of its own spacecraft.


Bob... Ninja Assimilated
"The Light" - Jefferson Starship-Windows of Heaven Album
I'm an Earthling with a Martian Soul wanting to go Home.   
You have to turn your own lightbulb on. ©stevo25 & rhw007
Reply
#46
looks like plumes are jetting out and increasing spin rate.

OSIRIS-REx reveals asteroid Bennu has big surprises
March 19, 2019 by Dwayne Brown / Joanna Wendel, NASA

[Image: osirisrexrev.jpg]
This view of asteroid Bennu ejecting particles from its surface on January 19 was created by combining two images taken on board NASA’s OSIRIS-REx spacecraft. Other image processing techniques were also applied, such as cropping and adjusting the brightness and contrast of each image. Credit: NASA/Goddard/University of Arizona/Lockheed Martin
A NASA spacecraft that will return a sample of a near-Earth asteroid named Bennu to Earth in 2023 made the first-ever close-up observations of particle plumes erupting from an asteroid's surface. Bennu also revealed itself to be more rugged than expected, challenging the mission team to alter its flight and sample collection plans, due to the rough terrain. 




Bennu is the target of NASA's Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer (OSIRIS-REx) mission, which began orbiting the asteroid on Dec. 31. Bennu, which is only slightly wider than the height of the Empire State Building, may contain unaltered material from the very beginning of our solar system.

"The discovery of plumes is one of the biggest surprises of my scientific career," said Dante Lauretta, OSIRIS-REx principal investigator at the University of Arizona, Tucson. "And the rugged terrain went against all of our predictions. Bennu is already surprising us, and our exciting journey there is just getting started."

Shortly after the discovery of the particle plumes on Jan. 6, the mission science team increased the frequency of observations, and subsequently detected additional particle plumes during the following two months. Although many of the particles were ejected clear of Bennu, the team tracked some particles that orbited Bennu as satellites before returning to the asteroid's surface.

The OSIRIS-REx team initially spotted the particle plumes in images while the spacecraft was orbiting Bennu at a distance of about one mile (1.61 kilometers). Following a safety assessment, the mission team concluded the particles did not pose a risk to the spacecraft. The team continues to analyze the particle plumes and their possible causes.

"The first three months of OSIRIS-REx's up-close investigation of Bennu have reminded us what discovery is all about—surprises, quick thinking, and flexibility," said Lori Glaze, acting director of the Planetary Science Division at NASA Headquarters in Washington. "We study asteroids like Bennu to learn about the origin of the solar system. OSIRIS-REx's sample will help us answer some of the biggest questions about where we come from."

OSIRIS-REx launched in 2016 to explore Bennu, which is the smallest body ever orbited by spacecraft. Studying Bennu will allow researchers to learn more about the origins of our solar system, the sources of water and organic molecules on Earth, the resources in near-Earth space, as well as improve our understanding of asteroids that could impact Earth.



The OSIRIS-REx team also didn't anticipate the number and size of boulders on Bennu's surface. From Earth-based observations, the team expected a generally smooth surface with a few large boulders. Instead, it discovered Bennu's entire surface is rough and dense with boulders. 

The higher-than-expected density of boulders means that the mission's plans for sample collection, also known as Touch-and-Go (TAG), need to be adjusted. The original mission design was based on a sample site that is hazard-free, with an 82-foot (25-meter) radius. However, because of the unexpectedly rugged terrain, the team hasn't been able to identify a site of that size on Bennu. Instead, it has begun to identify candidate sites that are much smaller in radius.

The smaller sample site footprint and the greater number of boulders will demand more accurate performance from the spacecraft during its descent to the surface than originally planned. The mission team is developing an updated approach, called Bullseye TAG, to accurately target smaller sample sites.

"Throughout OSIRIS-REx's operations near Bennu, our spacecraft and operations team have demonstrated that we can achieve system performance that beats design requirements," said Rich Burns, the project manager of OSIRIS-REx at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "Bennu has issued us a challenge to deal with its rugged terrain, and we are confident that OSIRIS-REx is up to the task." 

The original, low-boulder estimate was derived both from Earth-based observations of Bennu's thermal inertia—or its ability to conduct and store heat—and from radar measurements of its surface roughness. Now that OSIRIS-REx has revealed Bennu's surface up close, those expectations of a smoother surface have been proven wrong. This suggests the computer models used to interpret previous data do not adequately predict the nature of small, rocky, asteroid surfaces. The team is revising these models with the data from Bennu. 

The OSIRIS-REx science team has made many other discoveries about Bennu in the three months since the spacecraft arrived at the asteroid, some of which were presented Tuesday at the 50th Lunar and Planetary Conference in Houston and in a special collection of papers issued by the journal Nature

The team has directly observed a change in the spin rate of Bennu as a result of what is known as the Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) effect. The uneven heating and cooling of Bennu as it rotates in sunlight is causing the asteroid to increase its rotation speed. As a result, Bennu's rotation period is decreasing by about one second every 100 years. Separately, two of the spacecraft's instruments, the MapCam color imager and the OSIRIS-REx Thermal Emission Spectrometer (OTES), have made detections of magnetite on Bennu's surface, which bolsters earlier findings indicating the interaction of rock with liquid water on Bennu's parent body. 

[Image: 1x1.gif] Explore further: NASA's first look: Tiny asteroid is studded with boulders

More information: The unexpected surface of asteroid (101955) Bennu, Nature (2019). DOI: 10.1038/s41586-019-1033-6, www.nature.com/articles/s41586-019-1033-6

Shape of (101955) Bennu indicative of a rubble pile with internal stiffness, DOI: 10.1038/s41561-019-0330-x , www.nature.com/articles/s41561-019-0330-x

Properties of rubble-pile asteroid (101955) Bennu from OSIRIS-REx imaging and thermal analysis, DOI: 10.1038/s41550-019-0731-1 , www.nature.com/articles/s41550-019-0731-1

Evidence for widespread hydrated minerals on asteroid (101955) Bennu, DOI: 10.1038/s41550-019-0722-2 , www.nature.com/articles/s41550-019-0722-2

The operational environment and rotational acceleration of asteroid (101955) Bennu from OSIRIS-REx observations, DOI: 10.1038/s41467-019-09213-x , 
www.nature.com/articles/s41467-019-09213-x


The dynamic geophysical environment of (101955) Bennu based on OSIRIS-REx measurements, DOI: 10.1038/s41550-019-0721-3 , www.nature.com/articles/s41550-019-0721-3

Craters, boulders and regolith of (101955) Bennu indicative of an old and dynamic surface, DOI: 10.1038/s41561-019-0326-6 , www.nature.com/articles/s41561-019-0326-6 

Along the vines of the Vineyard.
With a forked tongue the snake singsss...
Reply
#47
AUGUST 9, 2019
Asteroid's features to be named after mythical birds
by NASA's Goddard Space Flight Center
[Image: asteroidsfea.jpg]This image shows asteroid Bennu’s boulder-covered surface. It was taken by the PolyCam camera on NASA’s OSIRIS-REx spacecraft on April 11, 2019, from a distance of 2.8 miles (4.5 km). The field of view is 211 ft (64.4 m), and the large boulder in the upper right corner of the image is 50 ft (15.4 m) tall. When the image was taken, the spacecraft was over the southern hemisphere, pointing PolyCam far north and to the west. Credit: NASA/Goddard/University of Arizona
Working with NASA's OSIRIS-REx team, the International Astronomical Union's Working Group for Planetary System Nomenclature (WGPSN) approved the theme "birds and bird-like creatures in mythology" for naming surface features on asteroid (101955) Bennu.

OSIRIS-REx is NASA's first mission to bring a sample from an asteroid back to Earth. The OSIRIS-REx spacecraft has been mapping Bennu's surface since its arrival on Dec. 3, 2018, looking for a site from which to take a sample. Bennu is the smallest body in the solar system to be orbited and surveyed by a spacecraft at close range.
The named features on Bennu will include several terrain classification types that the IAU also approved for asteroid (162173) Ryugu's surface features (currently being explored by the Japanese Space Agency's Hayabusa2 spacecraft). These include craters, dorsa (peaks or ridges), fossae (grooves or trenches) and saxa (rocks and boulders). The last of these types—saxum—is a new feature classification that the IAU introduced earlier this year for small, rocky asteroids like Ryugu and Bennu. These surface features on Bennu will be named after mythological birds and bird-like creatures, complementing the mission's existing naming theme, which is rooted in Egyptian mythology.
The name OSIRIS-REx is an acronym for the mission's major concepts and goals, which stands for Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer. The name also finds inspiration in the Egyptian myth of the god Osiris. In ancient Egyptian mythology, Osiris is associated with the afterlife, the underworld and rebirth. He granted all life, including sprouting vegetation and the fertile flooding of the Nile River. Similarly, the OSIRIS-REx mission seeks to understand the origin and process of life on Earth by studying Bennu's carbon-rich regolith.
Bennu was named in 2013 by a 9-year-old boy from North Carolina who won the Name that Asteroid! Competition, a collaboration between the mission, the Planetary Society, and the LINEAR asteroid survey that discovered Bennu. Michael Puzio won the contest by suggesting that the spacecraft's Touch-and-Go Sample Mechanism (TAGSAM) arm and solar panels resemble the neck and wings in illustrations of Bennu, whom ancient Egyptians usually depicted as a gray heron. Bennu is the ancient Egyptian deity linked with the Sun, creation and rebirth—Puzio also noted that Bennu is the living symbol of Osiris. The myth of Bennu suits the asteroid itself, given that it is a primitive object that dates back to the creation of the Solar System. Themes of origins, rebirth and duality are all part of this asteroid's story. Birds and bird-like creatures are also symbolic of rebirth, creation and origins in various ancient myths.
The process of naming of Bennu's surface and features will begin this summer. The OSIRIS-REx team is scheduled to begin detailed reconnaissance on candidate sample sites this fall. Sample collection is scheduled for summer 2020, and the sample will return to Earth in September 2023.


[size=undefined]

Explore further
OSIRIS-REx breaks another orbit record[/size]


[size=undefined]
Provided by NASA's Goddard Space Flight Center[/size]
Along the vines of the Vineyard.
With a forked tongue the snake singsss...
Reply
#48
Quote:Counterintuitive physics property found to be widespread in living organisms

In order to further adapt to Bennu's ruggedness, the OSIRIS-REx team has made other adjustments to its sample site identification process.
The original mission plan envisioned a sample site with a radius of 82 feet (25 m).
Boulder-free sites of that size don't exist on Bennu, so the team has instead identified sites ranging from 16 to 33 feet (5 to 10 m) in radius. In order for the spacecraft to accurately target a smaller site, the team reassessed the spacecraft's operational capabilities to maximize its performance.



AUGUST 13, 2019
NASA mission selects final four site candidates for asteroid sample return
by NASA's Goddard Space Flight Center

[Image: nasamissions.jpg]Pictured are the four candidate sample collection sites on asteroid Bennu selected by NASA’s OSIRIS-REx mission. Site Nightingale (top left) is located in Bennu’s northern hemisphere. Sites Kingfisher (top right) and Osprey (bottom left) are located in Bennu’s equatorial region. Site Sandpiper (bottom right) is located in Bennu’s southern hemisphere. In December, one of these sites will be chosen for the mission’s touchdown event. Credit: NASA/University of Arizona
After months grappling with the rugged reality of asteroid Bennu's surface, the team leading NASA's first asteroid sample return mission has selected four potential sites for the Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer (OSIRIS-REx) spacecraft to "tag" its cosmic dance partner.

Since its arrival in December 2018, the OSIRIS-REx spacecraft has mapped the entire asteroid in order to identify the safest and most accessible spots for the spacecraft to collect a sample. These four sites now will be studied in further detail in order to select the final two sites—a primary and backup—in December.
The team originally had planned to choose the final two sites by this point in the mission. Initial analysis of Earth-based observations suggested the asteroid's surface likely contains large "ponds" of fine-grain material. The spacecraft's earliest images, however, revealed Bennu has an especially rocky terrain. Since then, the asteroid's boulder-filled topography has created a challenge for the team to identify safe areas containing sampleable material, which must be fine enough—less than 1 inch (2.5 cm) diameter—for the spacecraft's sampling mechanism to ingest it.
"We knew that Bennu would surprise us, so we came prepared for whatever we might find," said Dante Lauretta, OSIRIS-REx principal investigator at the University of Arizona, Tucson. "As with any mission of exploration, dealing with the unknown requires flexibility, resources and ingenuity. The OSIRIS-REx team has demonstrated these essential traits for overcoming the unexpected throughout the Bennu encounter."
The original mission schedule intentionally included more than 300 days of extra time during asteroid operations to address such unexpected challenges. In a demonstration of its flexibility and ingenuity in response to Bennu's surprises, the mission team is adapting its site selection process. Instead of down-selecting to the final two sites this summer, the mission will spend an additional four months studying the four candidate sites in detail, with a particular focus on identifying regions of fine-grain, sampleable material from upcoming, high-resolution observations of each site. The boulder maps that citizen science counters helped create through observations earlier this year were used as one of many pieces of data considered when assessing each site's safety. The data collected will be key to selecting the final two sites best suited for sample collection.

In order to further adapt to Bennu's ruggedness, the OSIRIS-REx team has made other adjustments to its sample site identification process. The original mission plan envisioned a sample site with a radius of 82 feet (25 m). Boulder-free sites of that size don't exist on Bennu, so the team has instead identified sites ranging from 16 to 33 feet (5 to 10 m) in radius. In order for the spacecraft to accurately target a smaller site, the team reassessed the spacecraft's operational capabilities to maximize its performance. The mission also has tightened its navigation requirements to guide the spacecraft to the asteroid's surface, and developed a new sampling technique called "Bullseye TAG," which uses images of the asteroid surface to navigate the spacecraft all the way to the actual surface with high accuracy. The mission's performance so far has demonstrated the new standards are within its capabilities.
"Although OSIRIS-REx was designed to collect a sample from an asteroid with a beach-like area, the extraordinary in-flight performance to date demonstrates that we will be able to meet the challenge that the rugged surface of Bennu presents," said Rich Burns, OSIRIS-REx project manager at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "That extraordinary performance encompasses not only the spacecraft and instruments, but also the team who continues to meet every challenge that Bennu throws at us."

Since arriving at near-Earth asteroid Bennu in December 2018, NASA's OSIRIS-REx mission has been studying this small world of boulders, rocks, and loose rubble - and looking for a place to touch down. The goal of OSIRIS-REx is to collect a sample of Bennu in mid-2020, and return it to Earth in late 2023. Credit: NASA
The four candidate sample sites on Bennu are designated Nightingale, Kingfisher, Osprey, and Sandpiper—all birds native to Egypt. The naming theme complements the mission's two other naming conventions—Egyptian deities (the asteroid and spacecraft) and mythological birds (surface features on Bennu).
The four sites are diverse in both geographic location and geological features. While the amount of sampleable material in each site has yet to be determined, all four sites have been evaluated thoroughly to ensure the spacecraft's safety as it descends to, touches and collects a sample from the asteroid's surface.
Nightingale is the northern-most site, situated at 56 degrees north latitude on Bennu. There are multiple possible sampling regions in this site, which is set in a small crater encompassed by a larger crater 459 feet (140 m) in diameter. The site contains mostly fine-grain, dark material and has the lowest albedo, or reflection, and surface temperature of the four sites.
Kingfisher is located in a small crater near Bennu's equator at 11 degrees north latitude. The crater has a diameter of 26 feet (8 m) and is surrounded by boulders, although the site itself is free of large rocks. Among the four sites, Kingfisher has the strongest spectral signature for hydrated minerals.
Osprey is set in a small crater, 66 feet (20 m) in diameter, which is also located in Bennu's equatorial region at 11 degrees north latitude. There are several possible sampling regions within the site. The diversity of rock types in the surrounding area suggests that the regolith within Osprey may also be diverse. Osprey has the strongest spectral signature of carbon-rich material among the four sites.
Sandpiper is located in Bennu's southern hemisphere, at 47 degrees south latitude. The site is in a relatively flat area on the wall of a large crater 207 ft (63 m) in diameter. Hydrated minerals are also present, which indicates that Sandpiper may contain unmodified water-rich material.
This fall, OSIRIS-REx will begin detailed analyses of the four candidate sites during the mission's reconnaissance phase. During the first stage of this phase, the spacecraft will execute high passes over each of the four sites from a distance of 0.8 miles (1.29 km) to confirm they are safe and contain sampleable material. Closeup imaging also will map the features and landmarks required for the spacecraft's autonomous navigation to the asteroid's surface. The team will use the data from these passes to select the final primary and backup sample collection sites in December.
The second and third stages of reconnaissance will begin in early 2020 when the spacecraft will perform passes over the final two sites at lower altitudes and take even higher resolution observations of the surface to identify features, such as groupings of rocks that will be used to navigate to the surface for sample collection. OSIRIS-REx sample collection is scheduled for the latter half of 2020, and the spacecraft will return the asteroid samples to Earth on Sept. 24, 2023.


[size=undefined]

Explore further
OSIRIS-REx breaks another orbit record[/size]


[size=undefined]
More information: Explore the final four candidate sites in detail: www.asteroidmission.org/candidate-sample-sites
Provided by NASA's Goddard Space Flight Center[/size]


[size=undefined]https://phys.org/news/2019-08-nasa-missi...eroid.html[/size]

(09-09-2016, 11:12 PM)EA Wrote: ~7 years from NOW.(nice Top-Hat btw  -kudos: adept @ egypt!)

[Image: bennu_bird_by_ropen7789-da8kqaj.png]
Icy comets serve as storks for life on Earth
July 8, 2015
[Image: 16071174053_28296c0153_o.jpg]
In order to further adapt to Bennu's ruggedness, the OSIRIS-REx team has made other adjustments to its sample site identification process. The original mission plan envisioned a sample site with a radius of 82 feet (25 m). Boulder-free sites of that size don't exist on Bennuso the team has instead identified sites ranging from 16 to 33 feet (5 to 10 m) in radius. In order for the spacecraft to accurately target a smaller site, the team reassessed the spacecraft's operational capabilities to maximize its performance.
[Image: icycometsser.jpg]
This simulation depicts a comet hitting the young Earth, generating the amino acids necessary for life. Image courtesy of Matthew Genge/Imperial College London.
Early Earth was an inhospitable place where the planet was often bombarded by comets and other large astrophysical bodies.



Read more at: http://phys.org/news/2015-07-icy-comets-...h.html#jCp



What does the Asteroid Bennu serve as?


Phoenix Symbolically is as Bennu Symbiotically was?


Philae's comet may host alien 'life': astronomers

July 7, 2015



[Image: 1-animagetaken.jpg]
An image taken by Rosetta's Philae on comet 67P/Churyumov-Gerasimenko shows part of the lander, in a photo released by the European Space Agency (ESA) on November 13, 2014
Astronomers proposed a novel explanation Monday for the strange appearance of the comet carrying Europe's robot probe Philae through outer space: alien microscopic life.





Read more at: http://phys.org/news/2015-07-philae-comet-host-alien-life.html#jCp


Levin will have his day.

  Full Circle Improv! 

Wickramasinghe will have his day.


AUGUST 13, 2019

Meteorite strikes made life on Earth possible

by University of Tübingen

[Image: meteoritestr.jpg]Clean lab facilities of the Isotope Geochemistry Laboratory, University of Tübingen (from left to right): Dr. María Isabel Varas-Reus, Dr. Stephan König and Aierken Yierpan. Credit: University of Tübingen
Meteorites from the far reaches of the solar system delivered large amounts of water, carbon and volatile substances to the Earth. Only then could the Earth host life. Dr. María Isabel Varas-Reus, Dr. Stephan König, Aierken Yierpan and Professor Dr. Ronny Schönberg from Tübingen University's Isotope Geochemistry Group, and Dr. Jean-Pierre Lorand from the Université de Nantes, provide evidence for this scenario in a new study. Using a method recently developed at the University of Tübingen, the researchers measured selenium isotopes in rocks derived from the Earth's mantle. Identical isotope signatures in these rocks and in certain types of meteorites revealed the origin of the selenium as well as large amounts of water and other vital substances. The study has been published in the latest Nature Geoscience.

Strictly speaking, there shouldn't be any selenium in the Earth's mantle. "It is attracted to iron. That is why, in the early history of our planet, it went down into the iron-rich core," Dr. María Isabel Varas-Reus explains. There was no more selenium in the Earth's outer layer. "The previous selenium signatures were completely erased there. The selenium found in the Earth's mantle today must therefore have been added after the formation of the Earth's core. Geologically speaking, "at the last moment of the formation of the Earth, after our moon had also formed," Varas-Reus adds. It's hard to say exactly when—it could have been between 4.5 and 3.9 billion years ago.
Complex measurements
In various places, the research team took samples of mantle rocks, which have been brought to the surface by plate tectonic processes and had remained unchanged with regard to its selenium isotope composition since the formation of the Earth. The researchers determined the isotope signature of the selenium in these rocks. Isotopes are atoms of the same chemical element with different weights. "It has been possible for some time now to measure selenium isotopes in high concentrations—for example in samples from rivers," says Varas-Reus. "However, the selenium concentration in high-temperature rocks is very low. Samples must be dissolved out at high temperatures, and selenium is volatile. This makes the measurements difficult." But recently it became possible to measure selenium isotopes in high-temperature rocks. Dr. Stephan König and his group of researchers developed a complex method as part of his ERC grant, the O2RIGIN project funded by the European Research Council.
It has long been suspected that meteorites added substances to the Earth's mantle. "But we thought they were meteorites from the inner solar system," Varas-Reus says. "So we were very surprised that the selenium isotope signature of the Earth's mantle closely matched a certain type of meteorite from the outer solar system. These are carbonaceous chondrites from the solar system beyond the asteroid belt, from the area of the planets Jupiter, Saturn, Uranus and Neptune. The selenium isotope signatures of various meteorites were collected by the geologist Dr. Jabrane Labidi, a former O2RIGIN collaborator, in a previous study.
The research team was also able to quantify what else—apart from selenium—these meteorites brought with them when they hit the early Earth. "According to our calculations, around 60 percent of the water on Earth today comes from this source. That is the only way oceans could eventually form," says Varas-Reus. Volatile substances from the meteorites contributed to the formation of the earth's protective atmosphere. "This created the conditions for life on Earth to develop in its present form."




[size=undefined]

Explore further
Formation of the moon brought water to Earth[/size]



[size=undefined]
More information: María Isabel Varas-Reus et al. Selenium isotopes as tracers of a late volatile contribution to Earth from the outer Solar System, Nature Geoscience (2019). DOI: 10.1038/s41561-019-0414-7
Journal information: Nature Geoscience [/url]

Provided by [url=https://phys.org/partners/university-of-t--bingen/]University of Tübingen


https://phys.org/news/2019-08-meteorite-life-earth.html

[/size]

Quote:researchers showed that a negative differential response also occurs in autocatalytic reactions—"self-catalyzing" reactions, or reactions that produce products that catalyze the reaction itself. 

Chicken or the Egg?

[Image: 16071174053_28296c0153_o.jpg]No such conundrum. Naughty
https://phys.org/news/2019-08-counterint...pread.html

Full Circle Thread Sews it all up to a point EYE make.

It Writes itself.
It Rights itself.
Itza Rite Itself.

Arrow

AUGUST 13, 2019 FEATURE
Counterintuitive physics property found to be widespread in living organisms
by Lisa Zyga , Phys.org
[Image: 1-counterintui.jpg]A negative differential response occurs in substrate inhibition, a process that occurs in about 20% of all known enzymes. Credit: Khopkins2010, Wikimedia Commons
Ever since the late 19th century, physicists have known about a counterintuitive property of some electric circuits called negative resistance. Typically, increasing the voltage in a circuit causes the electric current to increase as well. But under some conditions, increasing the voltage can cause the current to decrease instead. This basically means that pushing harder on the electric charges actually slows them down.

Due to the relationship between current, voltage, and resistance, in these situations the resistance produces power rather than consuming it, resulting in a "negative resistance." Today, negative resistance devices have a wide variety of applications, such as in fluorescent lights and Gunn diodes, which are used in radar guns and automatic door openers, among other devices.
Most known examples of negative resistance occur in human-engineered devices rather than in nature. However, in a new study published in the New Journal of Physics, Gianmaria Falasco and coauthors from the University of Luxembourg have shown that an analogous property called negative differential response is actually a widespread phenomenon that is found in many biochemical reactions that occur in living organisms. They identify the property in several vital biochemical processes, such as enzyme activity, DNA replication, and ATP production. It seems that nature has used this property to optimize these processes and make living things operate more efficiently at the molecular scale.
"This counterintuitive, yet common phenomenon has been found in a wealth of physical systems after its first discovery in low-temperature semiconductors," the researchers wrote in their paper. "We have shown that a negative differential response is a widespread phenomenon in chemistry with major consequences on the efficacy of biological and artificial processes."
As the researchers explained, a negative differential response can occur in biochemical systems that are in contact with multiple biochemical reservoirs. Each reservoir tries to pull the system to a different equilibrium point (like a balance point), so that the system is constantly exposed to competing thermodynamic forces.
When a system is in equilibrium with its surroundings, any small perturbation, or noise, affecting the reservoirs will typically cause an increase in the production rate of some product, in accordance with positive entropy. The production rate of a product can be thought of as a chemical current. From this perspective, the increase in noise that causes an increase in chemical current is analogous to the "normal" case in electric circuits in which an increase in voltage causes an increase in electric current.

But when a system in contact with multiple reservoirs becomes out of equilibrium, it may respond differently to noise. In an out-of-equilibrium system, additional factors come into play, so that an increase in noise decreases the chemical current. This negative differential response is analogous to the case in which electric circuits exhibit negative resistance.
In their work, the researchers identified several biological processes that have negative differential responses. One example is substrate inhibition, which is a process used by enzymes to regulate their ability to catalyze chemical reactions. When a single substrate molecule binds to an enzyme, the resulting enzyme-substrate complex decays into a product, generating a chemical current. On the other hand, when the substrate concentration is high, two substrate molecules may bind to an enzyme, and this double binding prevents the enzyme from producing more product. As an increase in substrate molecule concentration causes a decrease in the chemical current, this is a negative differential response.
As a second example, the researchers showed that a negative differential response also occurs in autocatalytic reactions—"self-catalyzing" reactions, or reactions that produce products that catalyze the reaction itself. Autocatalytic reactions occur throughout the body, such as in DNA replication and ATP production during glycolysis. The researchers showed that negative differential responses can arise when two autocatalytic reactions occur simultaneously in the presence of two different chemical concentrations (reservoirs) in an out-of-equilibrium system.
The researchers also identified negative differential responses in dissipative self-assembly, a process in which energy is needed for a system to self-assemble, making it far from equilibrium. Dissipative self-assembly occurs, for example, in the ATP-driven self-assembly of actin filaments—the long, thin microstructures in the cytoplasm of cells that give cells their structure.
Nature does everything for a reason, and the presence of negative differential response in living organisms is no exception. The researchers showed that this property imparts advantages for biochemical processes mainly in terms of energy efficiency. In substrate inhibition, for example, it allows a system to reach homeostasis with less energy than would otherwise be required. In dissipative self-assembly, the negative differential response allows the system to realize a nearly optimal signal-to-noise ratio, ultimately increasing the efficiency of the self-assembly process.


[size=undefined]

Explore further
Researchers get around bad gap problem with graphene by using negative differential resistance[/size]


[size=undefined]
More information: Gianmaria Falasco et al. "Negative differential response in chemical reactions." New Journal of PhysicsDOI: 10.1088/1367-2630/ab28be
Journal information: New Journal of Physics
[/size]


[size=undefined]https://phys.org/news/2019-08-counterint...pread.html[/size]
Reply


Forum Jump:


Users browsing this thread: 1 Guest(s)