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BIOSTIRLING-4SKA : A cost effective and efficient approach for a new generation of solar dish-Stirling plants based on storage and hybridization; An Energy demo project for Large Scale Infrastructures",

The BIOSTIRLING - 4SKA (B4S) is a EU demonstration project dealing with the implementation of a cost-effective and efficient new generation of solar dish-Stirling plants based on hybridization and efficient storage at the industrial scale. The main goal of the B4S demonstration project is the generation of electric power using simultaneously solar power and gas to supply an isolated system and act as a scalable example of potential power supply for many infrastructures, including future sustainable large scientific infrastructures. B4S build an interdisciplinary approach to address reliability, maintainability and costs of this technology. In April 2017, B4S successfully tested in Portugal the first world Stirling hybrid system providing about 4kW of power to a phased array of antennas, overcoming challenges in Stirling and hybridization and smartgrid technologies. B4SKA Consortium, with fourteen companies from six European countries, has performed the engineering, construction, assembly and experimental exploitation, under contract signed with the European to develop on off-grid demonstrator in Contenda (Moura) Portugal.

astro-ph.IM↗

The Sun and its educational spectrum

The aim of this paper is to encourage science educators and outreach groups to look appropriately at the Sun and consider it as an extraordinary pedagogical tool to teach science at all education stages, what we call here as the solar educational spectrum, i.e., from K-12 to higher education, to develop informal educational projects that may lead to reach more complex material and to enlarge the experience at each stage. We review the main aspects of the Sun as an appetizer of the endless source of ideas to perform informal educational projects outside of a structured curriculum. We end up our discussion by sharing our experience across the educational spectrum in Colombia and how we used it as a development instrument.

physics.ed-ph↗

On the quantum "self-teleportation" probability of a human body

The probability of quantum relocation of a human body, at a given distance, is estimated using two different methods, giving comparable results. Not only the obtained values for the probabilities are inconceivably small, but assumptions of a sci-fi nature are also necessary to ensure that they are not identical to zero. The notions of 'non-spatiality' and 'superselection rule' are also briefly discussed.

physics.pop-ph↗

Simulation on various topocentric points of the zodiac constellations

On the sighting of the constellations and their stars, they seem to be near each other at first sight but some of thema are actually quite further from the others. Froma the geocentric point view can the Zodiac Costellations be perceived as referential marks divided into terrestrial ecliptic, which are organized according to their shapes. In this paper are these star groups simulated in order to compare the shapes of these groups and the diverse coordinate system of the astronomy. Within the simulation is the distance measure light-year remplaced with a so-called program's default "unity" that uses a compilation in Python, where such distances are escalated to 1:10

physics.ed-ph↗

The Astrobiology of the Anthropocene

Human influence on the biosphere has been evident at least since the development of widespread agriculture, and some stratigraphers have suggested that the activities of modern civilization indicate a geological epoch transition. The study of the anthropocene as a geological epoch, and its implication for the future of energy-intensive civilizations, is an emerging transdisciplinary field in which astrobiology can play a leading role. Habitability research of Earth, Mars, and exoplanets examines extreme cases relevant for understanding climate change as a planetary process. Energy-intensive civilizations will also face thermodynamic limits to growth, which provides an important constraint for estimating the longevity of human civilization and guiding the search for extraterrestrial intelligence. We recommend that missions concepts such as LUVOIR, HabEx, and OST be pursued in order to make significant progress toward understanding the future evolution of life on our planet and the possible evolution of technological, energy-intensive life elsewhere in the universe.

astro-ph.EP↗

Are Alien Civilizations Technologically Advanced?

As we discover numerous habitable planets around other stars in the Milky Way galaxy, including the nearest star, Proxima Centauri, one cannot help but wonder why have we not detected evidence for an advanced alien civilization as of yet. The surfaces of other planets might show either relics of advanced civilizations that destroyed themselves by self-inflicted catastrophes or living civilizations that are technologically primitive. Such circumstances can only be revealed by visiting those planets and not by remote observations.

physics.pop-ph↗

Is quantum mechanics creationism, and not science?

I revisit the reply of Bohr to Einstein. Bohr's assertion that there are no causes in atomic scale systems is, as a closer analysis reveals, not in line with the Copenhagen interpretation since it would contain a statement about reality. What Bohr should have written is that there are no causes in mathematics, which is universally acknowledged. The law of causality requires physical effects to be due to physical causes. For this reason any theoretical model which replaces physical causes by mathematical objects is creationism, that is, it creates physical objects out of mathematical elements. I show that this is the case for most of quantum mechanics.

physics.hist-ph↗

Ethics, Information, and Our "It-from-Bit" Universe

Using information technology, humans have brought about the Information Revolution, which is changing the world faster and more profoundly than ever before. How is this possible? An answer is suggested by comments of James Moor, regarding Logical Malleability, in his classic paper, What Is Computer Ethics?, 1985. The present essay combines Moor's ideas with the hypothesis that all physical entities, including spacetime and the universe as a whole, are dynamic data structures. To show the usefulness of taking such an approach, in both physics and information ethics, a suggested it from bit model of the universe is briefly sketched, and relevant predictions are offered about the future of computer and information ethics.

physics.pop-ph↗

Nodes: A Proposed Solution to Fermi's Paradox

Within the SETI community, a school of thought holds that ET might prefer to send information physically in so-called "probes," rather than by radio or optical beacon, in effect, a message in a bottle. In this paper, a related solution to Fermi's Paradox (also known as the "Great Silence") is proposed whereby ET civilizations aggregate knowledge into a system of "nodes," interspersed throughout the galaxy. Each node explores and serves the local star systems, detecting through its exploration non-technological life, and enlisting newly emergent technological civilizations, such as ourselves, into its central system. Each node would download information to new member civilizations and upload information from those civilizations, passing it along to its immediately adjacent nodes, such that new information would pass through the entire galaxy at near light speed. The most local node would not be directly detectible by us until it signaled Earth in response to a detection of its artificial electromagnetic (EM) leakage. This is because Earth would not be in the narrow beam of the signal pathways between our local node and its adjacent nodes, nor between the local node and other local civilizations, while the spillover signal strength of far distant nodes would be too weak to be detectable. Thus, the Great Silence of the galaxy is simply the result of the fact that Earth is not currently situated within a communications pathway in an otherwise well interconnected galaxy.

physics.pop-ph↗

Rejuvenating the Contract of Academia With Society

Academia owes the public a fresh look at its education and research mission. First and foremost, researchers must communicate the results of their latest studies in a truthful and meaningful way. Second, the traditional boundaries among disciplines should be blurred since innovation often blossoms along these boundaries. Third, universities should develop courses which are relevant for the skills required in the job market today. Finally, professors should mentor the future leaders of science, technology, arts and humanities and not just replicate themselves.

physics.pop-ph↗

Effects of Sound Suppressors on Muzzle Velocity, Bullet Yaw, and Drag

Little has been published regarding whether and how sound suppressors impact bullet flight, including velocity, bullet yaw, and drag. These parameters were compared for four different bullets fired from a .300 Winchester Magnum under four different muzzle conditions (no device and three different suppressors). While effects were not observed in all cases, results indicate that sound suppressors can have the effect of reducing bullet yaw and drag significantly, and can also have small effects on muzzle velocity. Results further suggest that bullets with a propensity to yaw demonstrate significant reductions in yaw and drag when shot through a two stage symmetric suppressor versus unsuppressed or with a conventional mouse-hole/K-baffle design.

physics.pop-ph↗

Parallel paths across the Pacific: a speculative explanation for the dilep in Marshallese navigation

Traditional techniques used by navigators in the Marshall Islands include the use of wave patterns as influenced by reflection and refraction around islands. The dilep is one such pattern, apparently providing signals to guide a navigator directly between two distant islands; so far there is no agreed causal explanation for such a phenomenon. We propose a mechanism; this generates a number of qualitative and quantitative predictions that may in principle be tested against satellite photo evidence, hydrodynamic simulations, experiments by small boat navigators in the right conditions, and ethnographic reports.

physics.pop-ph↗

Steam balloon concept for lifting rockets to launch altitude

Launching orbital and suborbital rockets from a high altitude is beneficial because of e.g. nozzle optimisation and reduced drag. Aeroplanes and gas balloons have been used for the purpose. Here we present a concept where a balloon is filled with pure water vapour on ground so that it rises to the launch altitude. The system resembles a gas balloon because no onboard energy source is carried and no hard objects fall down. We simulate the ascent behaviour of the balloon. In the baseline simulation, we consider a 10 tonne rocket lifted to an altitude of 18 km. We model the trajectory of the balloon by taking into account steam adiabatic cooling, surface cooling, water condensation and balloon aerodynamic drag. The required steam mass proves to be only 1.4 times the mass of the rocket stage and the ascent time is around 10 minutes. For small payloads, surface cooling increases the relative amount of steam needed, unless insulation is applied to the balloon skin. The ground-filled steam balloon seems to be an attractive and sustainable method of lifting payloads such as rockets into high altitude.

physics.pop-ph↗

Gravitational collapse and structure formation in an expanding universe with dark energy

Observations show that the expansion of the Universe is accelerating. This requires that the dominant constituent of matter in the Universe has some unusual properties like negative pressure. This exotic component has been given the name dark energy. We work with the simplest model of dark energy, the cosmological constant introduced by Einstein. We study the evolution of spherical over-densities in such a model and show that there is a minimum over-density required for collapse: perturbations with a smaller amplitude do not collapse. This threshold is interesting as even perturbations with a positive over-density and negative energy do not collapse in finite time. Further, we show that perturbations with an amplitude larger than, but comparable to the threshold value, take a very long time to collapse. We compare the solutions with the case when dark energy is absent.

physics.pop-ph↗

Kepler's laws without calculus

Kepler's laws are derived from the inverse square law without the use of calculus and are simplified over previous such derivations.

physics.hist-ph↗

Taxonomy and Jargon in SETI as an Interdisciplinary Field of Study

While SETI is often thought of as a part of radio astronomy with optical SETI, artifact SETI, METI, and other approaches to finding intelligent life considered to be allied fields, SETI is better understood as an interdisciplinary field with many subfields, approaches, and components. In particular, Robert Bradbury has argued for a broad view of SETI between two extremes: "orthodox SETI," or radio communication SETI, and a "Dysonian Approach" that searches for the extreme effects of alien life on its environment. Here, I build on these ideas and attempt to organize the terminology and efforts of SETI within a single framework for SETI as an interdisciplinary and multipronged approach.

physics.pop-ph↗

"Thinking Quantum": Lectures on Quantum Theory

We present a conceptually clear introduction to quantum theory, deriving the theory from scratch from the point of view of quantum information, with focus on developing intuition and dispelling misconceptions. Different subsets of these lectures were taught to a wide variety of audiences, including exceptional high-school students in the International Summer School for Young Physicists (ISSYP) at Perimeter Institute, 2nd-year physics undergraduates at the University of Toronto, and 4th-year physics and math undergraduate and graduate students at Brock University. The lectures are completely self-contained, including all the necessary mathematical background: complex numbers, linear algebra, and probability theory. They cover topics such as the axioms of quantum theory, qubits, superposition, entanglement, the uncertainty principle, unitary transformations and evolution, quantum gates, projective measurements, Bell's theorem, interpretations of quantum mechanics, the no-cloning theorem, quantum teleportation, quantum algorithms, density operators, mixed states, von Neumann entropy, the Bloch sphere, quantum decoherence, Hamiltonians, the Schrödinger equation, canonical quantization, quantum harmonic oscillators, wavefunctions, and much more. The lectures also contain 111 proof-based problems and 51 computational exercises.

physics.pop-ph↗