First Three X-37b Missions Were Vehicle Characterization, 4th Next Month for Experiments

The U.S. Air Force on Friday made its first public confirmation that the X-37B unmanned space shuttle will be launched next month on the fourth flight of an Orbital Test Vehicle.

“We are excited about our fourth X-37B mission,” said Randy Walden, the director of the Air Force Rapid Capabilities Office. “With the demonstrated success of the first three missions, we’re able to shift our focus from initial checkouts of the vehicle to testing of experimental payloads.”

The Air Force said its Rapid Capabilities Office had collaborated with several partners to test “new experiments on this fourth flight for the X-37B program.”

What’s more, the mission will test the performance of an experimental propulsion system jointly developed by the Air Force Research Laboratory and Space and Missile Systems Center, as well as a NASA advanced materials investigation.

“We’re very pleased with the experiments lined-up for our fourth OTV Mission OTV-4,” Walden said. “We’ll continue to evaluate improvements to the space vehicle’s performance, but we’re honored to host these collaborative experiments that will help advance the state-of-the-art for space technology.”

link.

LLNL's National Ignition Facility Used to Compress Diamond, Simulate Interior of Jupiter

Lawrence Livermore scientists for the first time have experimentally re-created the conditions that exist deep inside giant planets, such as Jupiter, Uranus and many of the planets recently discovered outside our solar system.

Researchers can now re-create and accurately measure material properties that control how these planets evolve over time, information essential for understanding how these massive objects form. This study focused on carbon, the fourth most abundant element in the cosmos (after hydrogen, helium and oxygen), which has an important role in many types of planets within and outside our solar system. The research appears in the June 17 edition of the journal, Nature.

Using the largest laser in the world, the National Ignition Facility at Lawrence Livermore National Laboratory, teams from the Laboratory, University of California, Berkeley and Princeton University squeezed samples to 50 million times Earth's atmospheric pressure, which is comparable to the pressures at the center of Jupiter and Saturn. Of the 192 lasers at NIF, the team used 176 with exquisitely shaped energy versus time to produce a pressure wave that compressed the material for a short period of time. The sample – diamond – is vaporized in less than 10 billionths of a second.

Though diamond is the least compressible material known, the researchers were able to compress it to an unprecedented density greater than lead at ambient conditions.

"The experimental techniques developed here provide a new capability to experimentally reproduce pressure–temperature conditions deep in planetary interiors," said Ray Smith, LLNL physicist and lead author of the paper.

Such pressures have been reached before, but only with shock waves that also create high temperatures – hundreds of thousands of degrees or more – that are not realistic for planetary interiors. The technical challenge was keeping temperatures low enough to be relevant to planets. The problem is similar to moving a plow slowly enough to push sand forward without building it up in height. This was accomplished by carefully tuning the rate at which the laser intensity changes with time.

link.

Testing Scenarios for Archaeological Mussel Collection in South Africa

Stranded rocky shore mussels and their possible procurement during prehistory on the West Coast of South Africa

Author:

Jerardino

Abstract:

A number of competing or complementary approaches are often used to understand patterns in shellfish abundance in the archaeological record. The relative importance of environmental, behavioural or taphonomic factors lends support to these different models. In the context of South African West Coast shell middens, the procurement of washed-up (stranded) fauna (vertebrates and invertebrates) has been proposed as a possible subsistence adaptation since the Late Pleistocene. The collection of washed-up rocky shore mussels (Choromytilus meridionalis), particularly, has been suggested to account for shellfish species composition in West Coast sites. The objective of this paper is to test this scenario by means of field observations from natural assemblages (washed-up mussels and storm beach accumulations) and archaeological observations from ten late Holocene assemblages. Metrical observations of C. meridionalis shells are interpreted in terms of updated knowledge on the biology and ecology of this species and used to bring insight into the procurement of this species. This study shows that less than half of stranded mussels are edible, and that considerable search/handling costs are involved when procuring this source. Because of their low returns and unpredictability, mussels are much more likely to have been collected from exposed rocky reefs than from washed-up material.

First Observation of Dirac Monopoles (some papers ought to come with !!!s on the title)

Observation of Dirac monopoles in a synthetic magnetic field

Authors:

Ray et al

Abstract:

Magnetic monopoles—particles that behave as isolated north or south magnetic poles—have been the subject of speculation since the first detailed observations of magnetism several hundred years ago. Numerous theoretical investigations and hitherto unsuccessful experimental searches have followed Dirac’s 1931 development of a theory of monopoles consistent with both quantum mechanics and the gauge invariance of the electromagnetic field3. The existence of even a single Dirac magnetic monopole would have far-reaching physical consequences, most famously explaining the quantization of electric charge. Although analogues of magnetic monopoles have been found in exotic spin ices and other systems there has been no direct experimental observation of Dirac monopoles within a medium described by a quantum field, such as superfluid helium-3. Here we demonstrate the controlled creation of Dirac monopoles in the synthetic magnetic field produced by a spinor Bose–Einstein condensate. Monopoles are identified, in both experiments and matching numerical simulations, at the termini of vortex lines within the condensate. By directly imaging such a vortex line, the presence of a monopole may be discerned from the experimental data alone. These real-space images provide conclusive and long-awaited experimental evidence of the existence of Dirac monopoles. Our result provides an unprecedented opportunity to observe and manipulate these quantum mechanical entities in a controlled environment.

Proposed Upgrade to HAARP Facility in Alaska for Doing Atmospheric Testing for Space Power Systems

Towards Space Solar Power - Examining Atmospheric Interactions of Power Beams with the HAARP Facility

Authors:

Leitgab and Cowley

Abstract:

In the most common space solar power (SSP) system architectures, solar energy harvested by large satellites in geostationary orbit is transmitted to Earth via microwave radiation. Currently, only limited information about the interactions of microwave beams with energy densities of several tens to hundreds of W/m2 with the different layers of the atmosphere is available. Governmental bodies will likely require detailed investigations of safety and atmospheric effects of microwave power beams before issuing launch licenses for SSP satellite systems. This paper proposes to collect representative and comprehensive data of the interaction of power beams with the atmosphere by extending the infrastructure of the High Frequency Active Auroral Research Program (HAARP) facility in Alaska, USA. Estimates of the transmission infrastructure performance as well as measurement devices and scientific capabilities of possible upgrade scenarios will be discussed. The proposed upgrade of the HAARP facility is expected to deliver a wealth of data and information which could serve as a decision base for governmental launch licensing of SSP satellites, and which can be used in addition to deepen public acceptance of SSP as a large-scale renewable energy source.

Is Time an Artifact of Being the Restricted Observer?

Time is an emergent phenomenon that is a side effect of quantum entanglement, say physicists. And they have the first exprimental results to prove it

When the new ideas of quantum mechanics spread through science like wildfire in the first half of the 20th century, one of the first things physicists did was to apply them to gravity and general relativity. The result were not pretty.

It immediately became clear that these two foundations of modern physics were entirely incompatible. When physicists attempted to meld the approaches, the resulting equations were bedeviled with infinities making it impossible to make sense of the results.

Then in the mid-1960s, there was a breakthrough. The physicists John Wheeler and Bryce DeWitt successfully combined the previously incompatible ideas in a key result that has since become known as the Wheeler-DeWitt equation. This is important because it avoids the troublesome infinites—a huge advance.

But it didn’t take physicists long to realise that while the Wheeler-DeWitt equation solved one significant problem, it introduced another. The new problem was that time played no role in this equation. In effect, it says that nothing ever happens in the universe, a prediction that is clearly at odds with the observational evidence.

This conundrum, which physicists call ‘the problem of time’, has proved to be thorn in flesh of modern physicists, who have tried to ignore it but with little success.

Then in 1983, the theorists Don Page and William Wooters came up with a novel solution based on the quantum phenomenon of entanglement. This is the exotic property in which two quantum particles share the same existence, even though they are physically separated.

Entanglement is a deep and powerful link and Page and Wooters showed how it can be used to measure time. Their idea was that the way a pair of entangled particles evolve is a kind of clock that can be used to measure change.

But the results depend on how the observation is made. One way to do this is to compare the change in the entangled particles with an external clock that is entirely independent of the universe. This is equivalent to god-like observer outside the universe measuring the evolution of the particles using an external clock.

In this case, Page and Wooters showed that the particles would appear entirely unchanging—that time would not exist in this scenario.

But there is another way to do it that gives a different result. This is for an observer inside the universe to compare the evolution of the particles with the rest of the universe. In this case, the internal observer would see a change and this difference in the evolution of entangled particles compared with everything else is an important a measure of time.

This is an elegant and powerful idea. It suggests that time is an emergent phenomenon that comes about because of the nature of entanglement. And it exists only for observers inside the universe. Any god-like observer outside sees a static, unchanging universe, just as the Wheeler-DeWitt equations predict.

link.  paper link.

So, someone who is outside the universe, all observing, doesn't see squat.  um.  theological problem, maybe?

A Little Experimental Paleontology: Tumbling Echinoderms

Experimental tumbling of echinoderms – taphonomic patterns and implications

Authors:

1. Przemysław Gorzelak (a)
2, Mariusz A. Salamon (b)

Affiliations:

a. Department of Biogeology, Institute of Paleobiology, Polish Academy of Sciences, Twarda Str. 51/55, 00–818 Warsaw, Poland

b. University of Silesia, Faculty of Earth Sciences, Department of Palaeontology and Biostratigraphy, Będzińska Str. 60, 41–200 Sosnowiec, Poland

Abstract:

Despite a wide array of published actualistic studies on echinoderm taphonomy the detailed pattern of decay and disarticulation of their skeletons is still not well understood. Here we provide results of tumbling experiments using a rotating barrel filled with artificial seawater and medium-sized quartz sand to mimic physical forces experienced by echinoderms during trasportation in high-energy conditions. In particular, we determined semi-quantitatively transportation-induced rates and patterns of damage and disintegration of freshly killed ophiuroid, asteroid and crinoid skeletons that were not allowed to decay initially. Our experiments showed that echinoderm specimens disintegrated in a characteristic sequence toward an increase of the degree of disarticulation, abrasion and roundness or thinness of echinoderm ossicles. The sequence of disintegration in crinoids began with the partial disintegration of distal arms after 2 hrs (a time equivalent to ~ 1 km of transport). The initial split of ophiuroid and asteroid arms and crinoid cirri occurred after 24 hrs (~ 12 km) and complete destruction of the asteroid mouth and ophiuroid disc area occurred after 72 hrs (~ 36 km). The duration of transport necessary to promote initial fragmentation in asteroid and ophiuroid arms and crinoid cirri into isolated ossicles was 120 hrs (~ 60 km). The complete disarticulation of crinoid, ophiuroid and asteroid arms and crinoid cirri occurred after 312 hrs (~ 156 km) and 408 hrs (~ 204 km), respectively. Although it has been argued that the quality of preservation can be a poor index of post-mortem transport, echinoderms allowed limited initial decay in the presence of rapid and relatively constant physical disturbance, an approximation of the distance of transport can be made.

Our data demonstrate that articulated ossicles can remain for several days, sufficient time for long (even a few hundred km) transporation. This finding illustrates that articulated echinoderm remains do not necessarily imply low energy and highlights the importance of a reliable discrimination of autochthonous and allochthonous components of fossil echinoderm assemblages. Application of isolated fossil echinoderm ossicles in e.g. paleoenvironmental and paleoecological reconstructions may lead to serious misinterpretations and should be supplemented by observations of abrasion traces.

Ancient Stromalites Disappeared Because of the Evolution of Foraminifera

The widespread disappearance of stromatolites, the earliest visible manifestation of life on Earth, may have been driven by single-celled organisms called foraminifera.

The findings, by scientists at Woods Hole Oceanographic Institution (WHOI); Massachusetts Institute of Technology; the University of Connecticut; Harvard Medical School; and Beth Israel Deaconess Medical Center, Boston, were published online the week of May 27 in the Proceedings of the National Academy of Sciences.

Stromatolites ("layered rocks") are structures made of calcium carbonate and shaped by the actions of photosynthetic cyanobacteria and other microbes that trapped and bound grains of coastal sediment into fine layers. They showed up in great abundance along shorelines all over the world about 3.5 billion years ago.

"Stromatolites were one of the earliest examples of the intimate connection between biology—living things—and geology—the structure of the Earth itself," said WHOI geobiologist Joan Bernhard, lead author of the study.

The growing bacterial community secreted sticky compounds that bound the sediment grains around themselves, creating a mineral "microfabric" that accumulated to become massive formations. Stromatolites dominated the scene for more than two billion years, until late in the Proterozoic Eon.

"Then, around 1 billion years ago, their diversity and their fossil abundance begin to take a nosedive," said Bernhard. All over the globe, over a period of millions of years, the layered formations that had been so abundant and diverse began to disappear. To paleontologists, their loss was almost as dramatic as the extinction of the dinosaurs millions of years later, although not as complete: Living stromatolites can still be found today, in limited and widely scattered locales, as if a few velociraptors still roamed in remote valleys.

While the extinction of the dinosaurs has largely been explained by the impact of a large meteorite, the crash of the stromatolites remains unsolved. "It's one of the major questions in Earth history," said WHOI microbial ecologist Virginia Edgcomb, a co-author on the paper.

Just as puzzling is the sudden appearance in the fossil record of different formations called thrombolites ("clotted stones"). Like stromatolites, thrombolites are produced through the action of microbes on sediment and minerals. Unlike stromatolites, they are clumpy, rather than finely layered.

It's not known whether stromatolites became thrombolites, or whether thrombolites arose independently of the decline in strombolites. Hypotheses proposed to explain both include changes in ocean chemistry and the appearance of multicellular life forms that might have preyed on the microbes responsible for their structure.

Bernhard and Edgcomb thought foraminifera might have played a role. Foraminifera (or "forams," for short) are protists, the kingdom that includes amoeba, ciliates, and other groups formerly referred to as "protozoa." They are abundant in modern-day oceanic sediments, where they use numerous slender projections called pseudopods to engulf prey, to move, and to continually explore their immediate environment. Despite their known ability to disturb modern sediments, their possible role in the loss of stromatolites and appearance of thrombolites had never been considered.

The researchers examined modern stromatolites and thrombolites from Highborne Cay in the Bahamas for the presence of foraminifera. Using microscopic and rRNA sequencing techniques, they found forams in both kinds of structures. Thrombolites were home to a greater diversity of foraminifera and were especially rich in forams that secrete an organic sheath around themselves. These "thecate" foraminifera were probably the first kinds of forams to evolve, not long (in geologic terms) before stromatolites began to decline.

"The timing of their appearance corresponds with the decline of layered stromatolites and the appearance of thrombolites in the fossil record," said Edgcomb. "That lends support to the idea that it could have been forams that drove their evolution."

Next, Bernhard, Edgcomb, and postdoctoral investigator Anna McIntyre-Wressnig created an experimental scenario that mimicked what might have happened a billion years ago.

"No one will ever be able to re-create the Proterozoic exactly, because life has evolved since then, but you do the best you can," Edgcomb said.

They started with chunks of modern-day stromatolites collected at Highborne Cay, and seeded them with foraminifera found in modern-day thrombolites. Then they waited to see what effect, if any, the added forams had on the stromatolites.

After about six months, the finely layered arrangement characteristic of stromatolites had changed to a jumbled arrangement more like that of thrombolites. Even their fine structure, as revealed by CAT scans, resembled that of thrombolites collected from the wild. "The forams obliterated the microfabric," said Bernhard.

Spooky Action At a Distance Has a Speed Limit

Chinese Physicists Measure Speed of “Spooky Action At a Distance”

Einstein railed against the possibility of spooky action at a distance because it violates relativity. Now Chinese physicists have clocked it travelling more than four orders of magnitude faster than light

One of the strangest concepts in quantum mechanics is the notion of entanglement. This is the idea that two quantum particles can be so deeply linked that they share the same existence. When that happens, a measurement on one immediately influences the other, regardless of the distance between them.

This “spooky action at a distance”, as Einstein called it, has puzzled and fascinated physicists since it was first discussed in the 1930s. Einstein initially used it as evidence of the failure of quantum mechanics since this instantaneous action clearly seemed to violate relativity.

Later, physicists realised there was no conflict because the “spooky action” cannot be used to send information faster than the speed of light. However, important questions remain about the nature of entanglement and spooky action. “If the spooky action does exist, what is its speed?” ask Juan Yin and pals at the University of Science and Technology of China in Shanghai.

Today, they reveal the answer. They say spooky action travels at least four orders of magnitude faster than light.

Fossil Insect Coloration

The fossil record of insect color illuminated by maturation experiments

Authors:

1. Maria E. McNamara (a,b)
2. Derek E.G. Briggs (a,c)
3. Patrick J. Orr (b)
4. Neal S. Gupta (d)
5. Emma R. Locatelli (a)
6. Lin Qiu (a)
7. Hong Yang (d)
8. Zhengrong Wang (a)
9. Heeso Noh (e)
10. Hui Cao (e)

Affiliations:

a. Department of Geology & Geophysics, Yale University, New Haven, Connecticut 06520, USA

b. UCD School of Geological Sciences, University College Dublin, Belfield, Dublin 4, Ireland

c. Yale Peabody Museum of Natural History, Yale University, New Haven, Connecticut 06520, USA

d. Laboratory for Terrestrial Environments, Department of Science and Technology, Bryant University, Smithfield, Rhode Island 02917, USA

e. Department of Applied Physics, Yale University, New Haven, Connecticut 06520, USA

Abstract:

Structural coloration underpins communication strategies in many extant insects but its evolution is poorly understood. This stems, in part, from limited data on how color alters during fossilization. We resolve this by using elevated pressures and temperatures to simulate the effects of burial on structurally colored cuticles of modern beetles. Our experiments show that the color generated by multilayer reflectors changes due to alteration of the refractive index and periodicity of the cuticle layers. Three-dimensional photonic crystals are equally resistant to degradation and thus their absence in fossil insects is not a function of limited preservation potential but implies that these color-producing nanostructures evolved recently. Structural colors alter directly to black above a threshold temperature in experiments, identifying burial temperature as the primary control on their preservation in fossils. Color-producing nanostructures can, however, survive in experimentally treated and fossil cuticles that now are black. An extensive cryptic record is thus available in fossil insects to illuminate the evolution of structural color.

Something Strange is Happening to Our Protons

The size of the proton

Authors:

1. Randolf Pohl (a)

2. Aldo Antognini (a)

3. François Nez (b)

4. Fernando D. Amaro (c)

5. François Biraben (b)

6. João M. R. Cardoso (c)

7. Daniel S. Covita (c,d)

8. Andreas Dax (e)

9. Satish Dhawan (e)

10. Luis M. P. Fernandes (c)

11. Adolf Giesen (f)

12. Thomas Graf (f)

13. Theodor W. Hänsch (a)

14. Paul Indelicato (b)

15. Lucile Julien (b)

16. Cheng-Yang Kao (g)

17. Paul Knowles (h)

18. Eric-Olivier Le Bigot (b)

19. Yi-Wei Liu (g)

20. José A. M. Lopes (c)

21. Livia Ludhova (h)

22. Cristina M. B. Monteiro (c)

23. Françoise Mulhauser (h)

24. Tobias Nebel (a)

25. Paul Rabinowitz (i)

26. Joaquim M. F. dos Santos (c)

27. Lukas A. Schaller (h)

28. Karsten Schuhmann (j)

29. Catherine Schwob (b)

30. David Taqqu (k)

31. João F. C. A. Veloso (d)

32. Franz Kottmann (l)

Affiliations:

a. Max-Planck-Institut für Quantenoptik, 85748 Garching, Germany

b. Laboratoire Kastler Brossel, École Normale Supérieure, CNRS, and Université P. et M. Curie-Paris 6, 75252 Paris, Cedex 05, France

c. Departamento de Física, Universidade de Coimbra, 3004-516 Coimbra, Portugal

d. I3N, Departamento de Física, Universidade de Aveiro, 3810-193 Aveiro, Portugal

e. Physics Department, Yale University, New Haven, Connecticut 06520-8121, USA

f. Institut für Strahlwerkzeuge, Universität Stuttgart, 70569 Stuttgart, Germany

g. Physics Department, National Tsing Hua University, Hsinchu 300, Taiwan

h. Département de Physique, Université de Fribourg, 1700 Fribourg, Switzerland

i. Department of Chemistry, Princeton University, Princeton, New Jersey 08544-1009, USA

j. Dausinger & Giesen GmbH, Rotebühlstr. 87, 70178 Stuttgart, Germany

k. Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland

l. Institut für Teilchenphysik, ETH Zürich, 8093 Zürich, Switzerland

Abstract:

The proton is the primary building block of the visible Universe, but many of its properties—such as its charge radius and its anomalous magnetic moment—are not well understood. The root-mean-square charge radius, rp, has been determined with an accuracy of 2 per cent (at best) by electron–proton scattering experiments1, 2. The present most accurate value of rp (with an uncertainty of 1 per cent) is given by the CODATA compilation of physical constants3. This value is based mainly on precision spectroscopy of atomic hydrogen4, 5, 6, 7 and calculations of bound-state quantum electrodynamics (QED; refs 8, 9). The accuracy of rp as deduced from electron–proton scattering limits the testing of bound-state QED in atomic hydrogen as well as the determination of the Rydberg constant (currently the most accurately measured fundamental physical constant3). An attractive means to improve the accuracy in the measurement of rp is provided by muonic hydrogen (a proton orbited by a negative muon); its much smaller Bohr radius compared to ordinary atomic hydrogen causes enhancement of effects related to the finite size of the proton. In particular, the Lamb shift10 (the energy difference between the 2S1/2 and 2P1/2 states) is affected by as much as 2 per cent. Here we use pulsed laser spectroscopy to measure a muonic Lamb shift of 49,881.88(76) GHz. On the basis of present calculations11, 12, 13, 14, 15 of fine and hyperfine splittings and QED terms, we find rp = 0.84184(67) fm, which differs by 5.0 standard deviations from the CODATA value3 of 0.8768(69) fm. Our result implies that either the Rydberg constant has to be shifted by −110 kHz/c (4.9 standard deviations), or the calculations of the QED effects in atomic hydrogen or muonic hydrogen atoms are insufficient.

A few bits.

First, its smaller than it ought to be using this experimental method (~4%).

Second, they do not know the source of the oddness.

Third, please keep in mind what happened with OPERA and the FTL neutrinos that it was supposedly producing.  This may also be a side effect of something obvious and stupid.

Fourth, that's a definitely physics paper byline.  ;)

Casimir Effect on a Chip!

One of the strangest effects to arise from the quantum nature of the universe is the Casimir force. This pushes two parallel conducting plates together when they are just a few dozen nanometres apart.

At these kinds of scales, the Casimir force can dominate and engineers are well aware of its unwanted effects. One reason why microelectromechanical machines have never reached their original promise is the stiction that Casimir forces can generate.

On the other hand, many engineers hope to exploit the Casimir force. Various theoretical models predict that the force should be repulsive between objects of certain shapes, a phenomenon that could prevent stiction.

But there is a problem: Casimir force experiments are extremely hard to do. One headache is that nobody has perfected the technology to position different objects accurately with a nanometre scale gap. Another is that microscopic objects tend to warp and bend; any corrugations on a flat surface can dramatically change the amount of Casimir force between them and even its direction. That makes experimental results hard to interpret.

Today, Jie Zou at the University of Florida and a few buddies take a big step towards changing this. These guys have carved a single device out of silicon that is capable of measuring the Casimir force between a pair of parallel silicon beams, the first on-chip device capable of doing this.

The device consists of one fixed beam and another moveable one attached to an electromechanical actuator. The team starts by measuring the separation between them using a scanning electron microscope. They then apply a voltage to the actuator, which pushes the movable beam towards the fixed beam.

The beams oscillate at a natural frequency, which Zou and co can easily measure. However, this frequency depends on the forces on the beams. So as the beams move closer together and the Casimir forces changes, so too does the oscillation frequency. This is how Zou and co measure the force.

Of course, there are other forces at play here too, such as residual electrostatic forces. When Zou and co take these into account, their results more or less exactly match theoretical predictions for the Casimir force that beams of this shape should generate.