SEARCH · Searcharxiv

Results for “physics.pop-ph”

Search indexed arXiv papers on artificial intelligence, large language models, computer vision and robotics. Read source abstracts and follow links to arXiv.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 199 records · Page 11Linked to original sources

arXiv2013

"Science in Tales": Analysis of the images of scientist in young people's fictional literature

In the research field on the "images of scientists" that appear in fictional literature, we focus on a set of tales produced by students of secondary school. Our aim is to connect some traits of the stereotypical scientist that appear in those texts with the traits underlying other cultural productions, since those productions may constitute the probable source of the stereotype. Many common representations of the scientist emerge from an image of science that is inadequate from the point of view of science teaching. It correlates to a lack of interest towards science courses. This lack of interest would contribute to stagnation in the number of students pursuing science and technology careers in Ibero-America in general and especially in Argentina.

physics.pop-ph↗

arXiv2013

Aurorae in Australian Aboriginal Traditions

Transient celestial phenomena feature prominently in the astronomical knowledge and traditions of Aboriginal Australians. In this paper, I collect accounts of the Aurora Australis from the literature regarding Aboriginal culture. Using previous studies of meteors, eclipses, and comets in Aboriginal traditions, I anticipate that the physical properties of aurora, such as their generally red colour as seen from southern Australia, will be associated with fire, death, blood, and evil spirits. The survey reveals this to be the case and also explores historical auroral events in Aboriginal cultures, aurorae in rock art, and briefly compares Aboriginal auroral traditions with other global indigenous groups, including the Maori of New Zealand.

physics.hist-ph↗

arXiv2013

Problem Complexity Research from Energy Perspective

Computational complexity is a particularly important objective. The idea of Landauer principle was extended through mapping three classic problems (sorting,ordered searching and max of N unordered numbers) into Maxwell demon thought experiment in this paper. The problems'complexity is defined on the entropy basis and the minimum energy required to solve them are rigorous deduced from the perspective of energy (entropy) and the second law of thermodynamics. Then the theoretical energy consumed by real program and basic operators of classical computer are both analyzed, the time complexity lower bounds of three problems'all possible algorithms are derived in this way. The lower bound is also deduced for the two n*n matrix multiplication problem. In the end, the reason why reversible computation is impossible and the possibility of super-linear energy consumption capacity which may be the power behind quantum computation are discussed, a conjecture is proposed which may prove NP!=P. The study will bring fresh and profound understanding of computation complexity.

cs.CC↗

arXiv2013

The genesis of the quantum theory of the chemical bond

An historical overview is given of the relevant steps that allowed the genesis of the quantum theory of the chemical bond, starting from the appearance of the new quantum mechanics and following later developments till approximately 1931. General ideas and some important details are discussed concerning molecular spectroscopy, as well as quantum computations for simple molecular systems performed within perturbative and variational approaches, for which the Born-Oppenheimer method provided a quantitative theory accounting for rotational, vibrational and electronic states. The novel concepts introduced by the Heitler-London theory, complemented by those underlying the method of the molecular orbitals, are critically analyzed along with some of their relevant applications. Further improvements in the understanding of the nature of the chemical bond are also considered, including the ideas of one-electron and three-electron bonds introduced by Pauling, as well as the generalizations of the Heitler-London theory firstly performed by Majorana, which allowed the presence of ionic structures into homopolar compounds and provided the theoretical proof of the stability of the helium molecular ion. The study of intermolecular interactions, as developed by London, is finally examined.

physics.hist-ph↗

arXiv2015

Analemmatic and Horizontal Sundials of the Bronze Age (Northern Black Sea Coast)

The paper presents the results of a study of unique plate with images of Srubna burial of tumuli group Popov Yar-2 (Ukraine) and plate of Srubna burial of tumulus field Tavriya-1 (Russia). A distinctive feature of the images is the orderliness and symmetry of the composition, as well as the location of elliptical cupped depressions. With the help of mathematical and astronomical methods we prove in this paper that the plates with the images are the ancient sundials. At the Popov Yar-2 plate located two sundials, which worked at the same time: the analemmatic sundial and the horizontal sundial with two gnomons and the linear scale. At the Tavriya-1 plate located analemmatic sundial. On the basis of the reconstruction of the linear parameters of the gnomon of both Popov Yar-2 plate sundials and given the scale value of horizontal sundial, in the article that the potential indirect impact protoscientific knowledge of ancient Egypt to the Srubna population in the Northern Black Sea coast. Srubna burial, plate, wells, cupped depressions, analemmatic, horizontal sundial, gnomon, archaeoastronomy, archeology

physics.hist-ph↗

arXiv2013

Establishment of the new Ecuadorian solar physics phenomena division

Crucial physical phenomena occur in the equatorial atmosphere and ionosphere, which are currently understudied and poorly understood. Then, scientific campaigns for monitoring equatorial region are required, which will provide the data for analyzing and creating adequate models. Ecuador is located in strategic geographical position where these studies can be performed, providing data for the scientific community working for understanding the nature of these physical systems. The Quito Astronomical Observatory of National Polytechnic School is working in this direction, promoting research in Space Sciences for studying the equatorial zone. With the participation and valuable collaboration of international initiatives like AWESOME, MAGDAS, SAVNET and CALLISTO, the Quito Observatory is creating a new space physics division on the basis of the International Space Weather Initiative. In this contribution, the aforementioned initiative is presented inviting leaders from others scientific projects to deploy their instruments and to join us giving the necessary support for the creation of this new strategic research center.

astro-ph.IM↗

arXiv2013

Towards Gigayear Storage Using a Silicon-Nitride/Tungsten Based Medium

Current digital data storage systems are able to store huge amounts of data. Even though the data density of digital information storage has increased tremendously over the last few decades, the data longevity is limited to only a few decades. If we want to preserve anything about the human race which can outlast the human race itself, we require a data storage medium designed to last for 1 million to 1 billion years. In this paper a medium is investigated consisting of tungsten encapsulated by siliconnitride which, according to elevated temperature tests, will last for well over the suggested time.

cs.ET↗

arXiv2013

Uncovering MIT wind myths through micro-climatological CFD analysis

Popular campus myths of unusually strong pedestrian level winds are investigated with a Computational Fluid Dynamics (CFD) approach. The numerical simulations confirm the existence of the reported phenomena and provide a qualitative explanation of their physical mechanisms.

physics.ao-ph↗

arXiv2014

A Thousand Problems in Cosmology: Horizons

This is one chapter of the collection of problems in cosmology, in which we assemble the problems, with solutions, that concern one of the most distinctive features of general relativity and cosmology---the horizons. The first part gives an elementary introduction into the concept in the cosmological context, then we move to more formal exposition of the subject and consider first simple, and then composite models, such as $Λ$CDM. The fourth section elevates the rigor one more step and explores the causal structure of different simple cosmological models in terms of conformal diagrams. The section on black holes relates the general scheme of constructing conformal diagrams for stationary black hole spacetimes. The consequent parts focus on more specific topics, such as the various problems regarding the Hubble sphere, inflation and holography. The full collection is available in the form of a wiki-based resource at universeinproblems.com. The cosmological community is welcome to contribute to its development.

physics.ed-ph↗

arXiv2013

A possible Harappan Astronomical Observatory at Dholavira

Astronomy arises very early in a civilization and evolves as the civilization advances. It is therefore reasonable to assume that a vibrant knowledge of astronomy would have been a feature of a civilization the size of the Harappan Civilization. We suggest that structures dedicated to astronomy existed in every major Harappan city. One such city was Dholavira, an important trading port that was located on an island in what is now the Rann of Kutch during the peak of the Harappan Civilization. We have analyzed an unusual structure at Dholavira that includes two circular rooms. Upon assuming strategically-placed holes in their ceilings we examine the internal movement of sunlight within these rooms and suggest that the larger structure of which they formed a part could have functioned as an astronomical observatory.

physics.hist-ph↗

arXiv2013

Habitability in the Solar System and New Planetary Missions

Definition of habitability depends on the organisms under consideration. One way to determine habitability of some environment is to compare its certain parameters to environments where extremophilic micro-organisms thrive on Earth. We can also define more common habitability criteria from the life as we know it. These criteria include basic elements, liquid water and an energy source. We know that some locations in our Solar System provide at least some of these limits and criteria. This article describes the aims and technical specifications of some planetary missions, such as NASAs MSL in 2012, ESAs ExoMars missions in 2016 and 2018, and JUICE in 2033. These missions will explore habitability of Mars, Europa, Ganymede and Callisto. Here we compare defined habitability criteria to instrumentation documentation to determine whether these missions could validate the habitability of Mars and those Jovian moons. These missions have about 13 habitability assessment related instruments for Mars, 3 for Europa, 5 for Ganymede and Callisto. I conclude that these missions will yield important information for habitability assessment of these targets.

physics.pop-ph↗

arXiv2014

A Simple Viscometer for High School and First Years Undergraduate Program Students: Theory and Experiment

A simple viscometer consists of mineral water bottle and trink straw is used to predict vicosity of water. A model is derived from Bernoulli's principle and Poiseulli's law. Value about 0.374 - 0.707 cP is obtained for observation in room temperature. About 10 minutes of observation time is needed to get the data. Keywords: equation of continuity, Bernoulli's equation, viscosity coefficient, Poiseulli flow.

physics.pop-ph↗

arXiv2014

Isaac Newton's sinister heraldry

After Isaac Newton was knighted by Queen Anne in 1705 he adopted an unusual coat of arms: a pair of human tibiae crossed on a black background, like a pirate flag without the skull. After some general reflections on Newton's monumental scientific achievements and on his enigmatic life, we investigate the story of his coat of arms. We also discuss how its simple design illustrates the concept of chirality, which would later play an important role in the philosophical arguments about Newton's conception of space, as well as in the development of modern chemistry and particle physics.

physics.hist-ph↗

arXiv2013

The Blue Box White Paper

This white paper is an explanation of Ben and Dave's TARDIS time machine, written for laypeople who are interested in time travel, but have no technical knowledge of Einstein's Theory of General Relativity. The first part of this paper is an introduction to the pertinent ideas from Einstein's theory of curved spacetime, followed by a review of other popular time machine spacetimes. We begin with an introduction to curvature and lightcones. We then explain the Alcubierre Warp Drive, the Morris-Thorne wormhole, and the Tipler cylinder. We then describe the Traversable Achronal Retrograde Domain in Spacetime (TARDIS), and explain some of its general properties. Our TARDIS is a bubble of spacetime curvature which travels along a closed loop in space and time. A person travelling within the bubble will feel a constant acceleration. A person outside of the TARDIS will see two bubbles: one which is evolving forwards in time, and one which is evolving backwards in time. We then discuss the physical limitations which may prevent us from ever constructing a TARDIS. Finally, we discuss the method through which a TARDIS can be used to travel between arbitrary points in space and time, and the possible dangers involved with exiting a TARDIS from the wrong side. Before we begin, would you like a Jelly Baby?

physics.pop-ph↗

arXiv2013

A Mixture of Ancient and Modern Understanding Concerning the Distance and Motion of the Moon

Ptolemy's model of the Moon's motion implied that its distance varies by nearly a factor of two, implying that its angular size should also vary by nearly a factor of two. We present an analysis of 100 naked eye observations of the Moon's angular size obtained over 1145 days, showing regular variations of at least 3 arc minutes. Thus, ancient astronomers could have shown that a key implication of Ptolemy's model was wrong. In modern times we attribute the variation of distance of the Moon to the combined effect of the ellipticity of the Moon's orbit and the perturbing effect of the Sun on the Earth-Moon system. We show graphically how this affects the ecliptic longitudes and radial distance of the Moon. The longitude and distance "anomalies" are correlated with the Moon's phase. This is illustrated without any complex equations or geometry.

physics.hist-ph↗

arXiv2013

Observations about Leonardo's drawings for Luca Pacioli

Three versions of Luca Pacioli's 'De Dvina Proportione' remain: a manuscript held in Milan, another in Geneva and a printed version edited in Venice. A recent book, 'Antologia della Divina Proporzione', has all three in one volume, allowing an easy comparison of the different versions. The present paper proposes some observations about these drawings, generally said to be of Leonardo da Vinci's hand.

math.HO↗

arXiv2013

A strange bridge by Leonardo

On folio 855 recto of the Codex Atlanticus, Leonardo da Vinci drew three 'easily movable' bridges, but one of them is enigmatic: all 'replicas' in Leonardo museums and exhibitions come as a surprise, to say the least, to any engineer or architect whose attention is drawn to it. This is the case for models in Amboise (France), Chicago and Portland (USA), Florence (Italy) and for the one of the traveling exhibition by the Australian company 'Grande Exhibitions' that already visited 40 major cities in the world. All 'replicas' of the bridge model attributed to Leonardo have pillars standing on the deck of the bridge, while the deck is suspended by cables attached on these pillars. At first sight this problem does not catch the attention of the observer, as the bridge seems to be a mixed form of a beam and a suspension bridge, but it was not overlooked by my colleague architect-engineer Dr. Laurens Luyten (Gent, Belgium). Yet, after a TV-interview in Brussels so much pressure was exerted by some of the museum collaborators, the architect prefers to keep the silence about the engineering by these 'scientific' exhibitions. Yet, it is the author's opinion the ridiculous models do not honor Leonardo, and so the present paper takes up the challenge to report about his observation in his name (with his permission). Something should be done, for sure: millions of people look at the bridge replicas that immediately embarrass any engineer.

math.HO↗

arXiv2013

Benford's Law: Textbook Exercises and Multiple-choice Testbanks

Benford's Law describes the finding that the distribution of leading (or leftmost) digits of innumerable datasets follows a well-defined logarithmic trend, rather than an intuitive uniformity. In practice this means that the most common leading digit is 1, with an expected frequency of 30.1%, and the least common is 9, with an expected frequency of 4.6%. The history and development of Benford's Law is inexorably linked to physics, yet there has been a dearth of physics-related Benford datasets reported in the literature. Currently, the most common application of Benford's Law is in detecting number invention and tampering such as found in accounting-, tax-, and voter-fraud. We demonstrate that answers to end-of-chapter exercises in physics and chemistry textbooks conform to Benford's Law. Subsequently, we investigate whether this fact can be used to gain advantage over random guessing in multiple-choice tests, and find that while testbank answers in introductory physics closely conform to Benford's Law, the testbank is nonetheless secure against such a Benford's attack for banal reasons.

physics.data-an↗