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In this report, a simple experimental system is shown, by which the temperature rise of global warming due to greenhouse gases can be demonstrated quantitatively. The system configuration is similar to that of the earth-atmosphere-space system based on a simple gray atmosphere model. The space (heat sink), the ground surface and the radiation power from the sun were replaced by a liquid nitrogen, and a black coated aluminum plated with an electric heater and an electric power of the heater, respectively. We believe that it can be a unique experimental system, that is useful for the study of the greenhouse effect in a laboratory, as well as for the educational demonstration tool of this phenomenon.

In this paper of "The Epistemology of Contemporary Physics" series we investigate Newton's third law and discuss and analyze its epistemological significance from some aspects with special attention to its relation to the principle of conservation of linear and angular momentum. The main issue in this investigation is the potential violations of this law according to the claims made in the literature of mainstream physics. This issue may cast a shadow on the validity of classical mechanics, and its Newtonian formulation in particular, formally and epistemologically and could have important implications and consequences on contemporary physics in general. However, what is more important about this issue from our perspective is the lack of clarity, comprehensibility and coherence in the investigation and analysis of this issue and its implications marked by the absence of appropriate conceptual and epistemological frameworks to deal with this issue properly and systematically. As a result, what we find in the literature is a collection of contradicting views which are mostly based on personal choices and preferences and selective or biased theoretical analysis with the lack of proper experimental verification and substantiation., Comment: 29 pages

On August 4 this year, Tsung-Dao Lee, a renowned theoretical physicist of Chinese origin, passed away at the age of 97. His most famous discovery dates back to 1956, when -- together with Chen-Ning Yang -- he postulated that parity symmetry might be broken by the weak interaction. They suggested experimental tests of this revolutionary idea, which were conducted within one year. The results confirmed the conjecture by Lee and Yang, thus changing a core paradigm of physics., Comment: 10 pages, LaTex, 5 figures

The Rosanna shuffle, the drum pattern from Toto's 1982 hit "Rosanna", is one of the most recognized drum beats in popular music. Recorded by Jeff Porcaro, this drum beat features a half-time shuffle with rapid triplets on the hi-hat and snare drum. In this analysis, we examine the timing and dynamics of the original drum track, focusing on rhythmic variations such as swing factor, microtiming deviations, tempo drift, and the overall dynamics of the hi-hat pattern. Our findings reveal that "Rosanna" exhibits a surprisingly pronounced swing for its genre, along with notable tempo drift typical of tracks recorded without a metronome. Additionally, we observe clear long-range correlations in the microtiming deviations, consistent with previous studies. Notably, the two-bar phrases of the song feature a distinctive repeating pattern in the timing and dynamics of the hi-hat beats, which enhances the song's phrasing. Overall, the Rosanna shuffle boasts a rich array of rhythmic characteristics that solidify its significant place in music history., Comment: 22 pages, 12 figures

The discovery of the Diary of Merer (papyri Wadi al-Jarf) allows us to see the Egyptian calendar applied in a logbook. The diary is dated to the 26th year of reign of Khufu and describes Merer and his crew transporting the limestone blocks from the Tura quarries to Akhet Khufu, that is, the pyramid of Khufu (Old Kingdom). We find a calendar with 30-day months, 10-day weeks, five epagomenal days (Tallet, 2017) and Merer's job adapted to the seasons of the year. Seasons and epagomenal days have names according to inscriptions on the east wall of the Tehne tomb of Nj-k'-'nh (Nikaiankh), end of Fourth Dynasty or early Fifth Dynasty. The Diary gives us an overall impression of extreme modernity in the logistics of ancient Egypt. And Merer looks like a person with a reputation for good timekeeping at Akhet Khufu., Comment: In this new layout, it is inserted a section about Pierre Tallet's paper regarding the Papyrus H, which is evidencing the epagomenal days. According to Pierre Tallet, 2017, the Wadi el-Jarf papyrus are the first attestation of the epagomenal days and, consequently, of the Egyptian Civil Calendar. A discussion about Ne-User-Re is also given

SETI is not a usual point of departure for environmental humanities. However, this paper argues that theories originating in this field have direct implications for how we think about viable inhabitation of the Earth. To demonstrate SETI's impact on environmental humanities, this paper introduces Fermi paradox as a speculative tool to probe possible trajectories of planetary history, and especially the "Sustainability Solution" proposed by Jacob Haqq-Misra and Seth Baum. This solution suggests that sustainable coupling between extraterrestrial intelligences and their planetary environments is the major factor in the possibility of their successful detection by remote observation. By positing that exponential growth is not a sustainable development pattern, this solution rules out space-faring civilizations colonizing solar systems or galaxies. This paper elaborates on Haqq-Misra's and Baum's arguments, and discusses speculative implications of the Sustainability Solution, thus rethinking three concepts in environmental humanities: technosphere, planetary history, and sustainability. The paper advocates that (1) technosphere is a transitory layer that shall fold back into biosphere; (2) planetary history must be understood in a generic perspective that abstracts from terrestrial particularities; and (3) sustainability is not sufficient vector of viable human inhabitation of the Earth, suggesting instead habitability and genesity as better candidates., Comment: 16 pages, 1 figure, 2 equations

In this paper we share the experience of the U.S. National Science Foundation (NSF) National Solar Observatory (NSO) scientists, educators and public outreach officers organizing an eclipse viewing party at a sports complex stadium on the US/Mexico border in Eagle Pass, TX in collaboration with educators from Eagle Pass and Uvalde areas. We describe reasons we chose Eagle Pass, contacts we established with the local community, preparations for and activities set up during the eclipse viewing party, the eclipse day on April 8 2024 and lessons learned from organizing our event., Comment: 17 pages, 9 figures, submitted to Bulletin of the AAS: Celebrating the Wonder of Science in the Shadow II

The Daisy World model has long served as a foundational framework for understanding the self-regulation of planetary biospheres, providing insights into the feedback mechanisms that may govern inhabited exoplanets. In this study, we extend the classic Daisy World model through the lens of Semantic Information Theory (SIT), aiming to characterize the information flow between the biosphere and planetary environment -- what we term the \emph{information architecture} of Daisy World systems. Our objective is to develop novel methodologies for analyzing the evolution of coupled planetary systems, including biospheres and geospheres, with implications for astrobiological observations and the identification of agnostic biosignatures. To operationalize SIT in this context, we introduce a version of the Daisy World model tailored to reflect potential conditions on M-dwarf exoplanets, formulating a system of stochastic differential equations that describe the co-evolution of the daisies and their planetary environment. Analysis of this Exo-Daisy World model reveals how correlations between the biosphere and environment intensify with rising stellar luminosity, and how these correlations correspond to distinct phases of information exchange between the coupled systems. This \emph{rein control} provides a quantitative description of the informational feedback between the biosphere and its host planet. Finally, we discuss the broader implications of our approach for developing detailed ExoGaia models of inhabited exoplanetary systems, proposing new avenues for interpreting astrobiological data and exploring biosignature candidates., Comment: 14 pages, 4 figures, 1 appendix

Quantifying the global reach of planetarium dome shows presents significant challenges due to the lack of standardized viewership tracking mechanisms across diverse planetarium venues. We present an analysis of the global impact of dome shows, presenting data regarding four documentary films from a single visualization lab. Specifically, we designed and administered a viewership survey of four long-running shows that contained cinematic scientific visualizations. Reported survey data shows that between 1.2 - 2.6 million people have viewed these four films across the 68 responding planetariums (mean: 1.9 million). When we include estimates and extrapolate for the 315 planetariums that licensed these shows, we arrive at an estimate of 16.5 - 24.1 million people having seen these films (mean: 20.3 million).

Earth remains the only known example of a planet with technology, and future projections of Earth's trajectory provide a basis and motivation for approaching the search for extraterrestrial technospheres. Conventional approaches toward projecting Earth's technosphere include applications of the Kardashev scale, which suggest the possibility that energy-intensive civilizations may expand to harness the entire energy output available to their planet, host star, or even the entire galaxy. In this study, we argue that the Kardashev scale is better understood as a "luminosity limit" that describes the maximum capacity for a civilization to harvest luminous stellar energy across a given spatial domain, and we note that thermodynamic efficiency will always keep a luminosity-limited technosphere from actually reaching this theoretical limit. We suggest the possibility that an advanced technosphere might evolve beyond this luminosity limit to draw its energy directly from harvesting stellar mass, and we also discuss possible trajectories that could exist between Earth today and such hypothetical "stellivores." We develop a framework to describe trajectories for long-lived technospheres that optimize their growth strategies between exploration and exploitation, unlike Earth today. We note that analyses of compact accreting stars could provide ways to test the stellivore hypothesis, and we more broadly suggest an expansion of technosignature search strategies beyond those that reside exactly at the luminosity limit., Comment: Submitted to Acta Astronautica

Black holes are extreme outcomes of General Relativity, and can form through a variety of ways, including gravitational collapse of massive stars, or quantum fluctuations in the early universe. Here, we ask the question of whether they can form via focusing of radiation by compact binaries or intense lasers, or via trapping at the light ring of black holes. We provide evidence that gravitational lensing of radiation from a small, finite number of sources is not a viable mechanism to form black holes., Comment: 4 pages, 1 figure

Unidentified Anomalous Phenomena (UAP) have historically been stigmatized and regarded as pseudoscience due to a general lack of robust evidence. Recently, however, the subject has gained interest among astronomers and the military. This review explores how astronomers can enhance our understanding of these enigmatic phenomena by focusing on empirical tests of specific hypotheses (e.g. the hypothesis of extraterrestrial visitations) rather than solely collecting and categorizing data. We compare the investigation of UAP to the process of calibration and interpretations of astronomical discoveries and propose a toy model involving a network of neuro-interface extraterrestrial probes to model exotic UAP. This model aids in predicting probe signatures and behaviour, improving detection methods, and addressing ethical concerns in UAP research., Comment: Submitted. Constructive comments welcome

Claims of the retrieval of crashed craft and vehicles from non-human intelligences (NHI) abound in popular culture and the media. For this article, we utilize the number of such claims to estimate the number of years expected before the occurrence of a Catastrophic Disclosure, a term which was defined at the 2023 Sol Foundation's inaugural conference as the accidental disclosure of conclusive evidence of the existence of NHI, outside of the control of human institutions, such as governments and militaries. Here, we will consider one possible example of this as the crash of a piloted spacecraft (or, an ET probe) in the middle of a busy metropolis. The distribution of humans on Earth's surface, the population as a function of time, and the fraction of individuals owning smartphones, also versus time, are each taken into account as foundations for a rigorous statistical analysis. The author adopts a skeptical approach and doesn't claim NHI or ET are real but uses their analysis as an educational example of critical thinking and application of standard statistical distributions to an issue which captures the imagination of the public like almost no other issue. Making the extraordinary assumptions that sentient species other than humans exist, are capable of constructing vehicles for transportation, and are sufficiently fallible that their technology can malfunction, it is possible to quantify potential answers to the question of how long it will be before smartphone imagery or video proofs appear on the internet and become irrevocable through classification in the modern era. The results of simulations of numerous different potential scenarios, of varying degrees of pessimism/optimism, indicate that, if NHI/ETs is/are real, catastrophic disclosure may actually happen accidentally rather soon, with the mean expected year being 2040+/-20 under the default assumptions., Comment: 8 pages, 3 figures, 4 equations, and 27 references

This paper addresses the problem of determining the optimum shape for a beer glass that minimizes the heat transfer while the liquid is consumed, thereby keeping it cold for as long as possible. The proposed solution avoids the use of insulating materials. The glass is modeled as a body of revolution generated by a smooth curve, constructed from a material with negligible thermal resistance, but insulated at the base. The ordinary differential equation describing the problem is derived from the first law of Thermodynamics applied to a control volume encompassing the liquid. This is an inverse optimization problem, aiming to find the shape of the glass (represented by curve $S$) that minimizes the heat transfer rate. In contrast, the direct problem aims to determine the heat transfer rate for a given geometry. The solution obtained here is analytic, and the resulting function describing the relation between height ans radius of the glass, is in closed form, providing a family of optimal glass shapes that can be manufactured by conventional methods. Special attention is payed to the dimensions and the capacity of the resulting shapes., Comment: 16 pages, 8 figures. arXiv admin note: substantial text overlap with arXiv:2402.18544

In 1927, during the fifth Solvay Conference, Einstein and Bohr described a double-slit interferometer with a "movable slit" that can detect the momentum recoil of one photon. Here, we report a faithful realization of the Einstein-Bohr interferometer using a single atom in an optical tweezer, cooled to the motional ground state in three dimensions. The single atom has an intrinsic momentum uncertainty comparable to a single photon, which serves as a movable slit obeying the minimum Heisenberg uncertainty principle. The atom's momentum wavefunction is dynamically tunable by the tweezer laser power, which enables observation of an interferometric visibility reduction at a shallower trap, demonstrating the quantum nature of this interferometer. We further identify classical noise due to atom heating and precession, illustrating a quantum-to-classical transition., Comment: 18 pages, 4 figures

Ian McGilchrist's works present the thesis that the two hemispheres of the brain have radically different modes of interacting with the world, and that their respective perceptions and functions must be properly integrated for a viable way forward. This proper integration requires restoring the right-brain to its proper place as "Master." I discuss a parallel to this insight in the dichotomous "worlds" of quantum and classical physics. In addition, I discuss the relevance of Whitehead's process philosophy, as well as the Taoist concepts of Yin and Yang, with particular attention to the importance and primacy of Yin underlying the quantum level as "Master.", Comment: Invited talk given at Conference: "Metaphysics and the Matter With Things," February, 2024. Center for Process Studies and CA Institute of Integral Studies

Normally a passive object launched from the Moon at less than the escape velocity orbits the Moon once and then crashes back to the launch site. We show that thanks to lunar gravity anomalies, for specific launch sites and directions, a passive projectile can remain in lunar orbit for up to 9 Earth days. We find that such sites exist at least on the lunar equator for prograde equatorial orbit launches. Three of the sites are located on the lunar nearside. We envision that this can be used to lift material from the Moon at low cost because it gives prolonged opportunities for an active spacecraft to catch the projectile. Passive projectiles can be made entirely from lunar material so that a stream of Earth-imported parts is not needed. To reduce the mass and cost of the launcher, the projectile mass can be scaled down with a corresponding increase in the launch frequency. The projectile launcher itself can be a coilgun, railgun, superconducting quenchgun, sling or any other device that can give a projectile an orbital speed of about 1.7 km/s., Comment: 11 pages, 7 figures

In this paper, we present a QUBO formulation designed to solve a series of generalisations of the LinkedIn queens game, a version of the N-queens problem. We adapt this formulation for several particular cases of the problem by trying to optimise the number of variables and interactions, improving the possibility of applying it on quantum hardware by means of Quantum Annealing or the Quantum Approximated Optimization Algorithm (QAOA). We also present two new types of problems, the Coloured Chess Piece Problem and the Max Chess Pieces Problem, with their corresponding QUBO formulations., Comment: 9 pages, 4 figures

The CMS at DESY outreach Instagram account (@cmsatdesy) serves as a platform for science communication and outreach for a large experimental particle physics group. The initiative aims to promote scientific research, engage young scientists in outreach activities, and showcase their contributions. Instagram was chosen for its strong alignment with the target demographic and its broad user base in Germany and internationally. The account highlights the work of young scientists, providing insights into their scientific journeys and disseminating particle physics outreach content. Multiple contributors collaborate on content creation, offering early career researchers opportunities for training in science communication while maintaining a manageable time commitment. This paper presents the evolution of the project, its initial objectives, target audience, and the experiences gained in content development and public engagement on social media platforms., Comment: 6 pages, 4 figures, 42nd International Conference on High Energy physics - ICHEP2024

The "frozen star" picture of black holes, based on the fact that an outside observer will never see a collapsing sphere shrink sufficiently to form a black hole horizon, was a historical obstacle to the understanding of black holes, and continues to be a stumbling point for students trying to understand horizons. Promoting the discrete steps in Zeno's original story of Achilles and the tortoise to a "Zeno time coordinate" provides a quantitative toy model that allows students to understand why the "frozen star" phenomenon does not mean that objects cannot fall into a black hole. The toy model can be used for teaching about this particular feature of black holes in an introductory setting that does not introduce the Schwarzschild metric and its tortoise coordinates., Comment: Accepted for publication at Eur. J. Phys

This year marks half a century since Stephen Hawking made his greatest scientific discovery by theoretically proving that black holes aint so black, as they behave like hot bodies with an absolute temperature that depends inversely on their mass. This discovery is expressed by a simple and elegant equation known as the Hawking temperature. The best way to commemorate this great scientific event is by bringing it to a wide audience. The simplest and most transparent and intuitive tool to achieve this goal is dimensional analysis. The objective of this work is to use this tool to derive the Hawking equation, reveal its meaning, and explore its main physical consequences., Comment: 12 pages, 7 figures

This article discusses the main aspects related to Bell's inequality, both theoretical and experimental. A new derivation of Bell's inequality is also presented, which stands out for its mathematical simplicity. The exposition is mainly intended for undergraduate physics students, and places special emphasis on clarifying the meaning and scope of Bell's theorem in the context of the Einstein-Podolski-Rosen experiment., Comment: 23 pages, in Portuguese language, 8 figures

The discovery and confirmation that some nuclides were formed soon after the Big Bang is one of the strongest arguments in favour of the Hot Big Bang theory. The process of combining protons and neutrons in a hot, expanding universe is known as Big Bang nucleosynthesis (or, occasionally, primordial nucleosynthesis). The only experiment that is currently constructed to be concurrently sensitive to all four known fundamental forces - gravitational, electromagnetic, strong and weak forces - is big bang nucleosynthesis, which offers our earliest test of cosmology. Combined, our theoretical comprehension of Big Bang nucleosynthesis and the measurement of primordial abundances constitute one of the most robust foundations for the conventional cosmological model. This deliberation provides modern calculations of Big Bang nucleosynthesis, help readers gain an intuitive knowledge of the process and give an overview of the most recent state-of-the-art measurements. Our trust in the current basic picture of cosmology is reinforced by the overall amazing agreement between Big Bang nucleosynthesis and many cosmological probes., Comment: 11 pages including 2 figures and 1 table

This is the first of a series of papers that we intend to publish about the epistemology of fundamental physics in its current state. One of the main objectives of these papers is to improve our understanding of fundamental physics (and modern physics in particular) from an epistemological and interpretative perspective (i.e. versus formal perspective). Another main objective is to investigate and assess the merit of searching for a unified physical theory (the so-called ``theory of everything'') considering the fact that contemporary physics is a collection of theories created and developed by different individuals and groups of scientists in different eras of history reflecting different levels of scientific, philosophical and epistemological development and dealing with largely separate physical phenomena and hence such unification may mean ``stitching together'' an inhomogeneous collection of theoretical structures which may be clumsy (if not impossible) at least from an epistemological viewpoint., Comment: 23 pages

Bicycle Power Meters have become ubiquitous as training aids in recent years. Many power meters purport to measure Left-Right Pedal Balance, which is a measure of the extent to which power generated by the application of torque to the left and right pedal differ. This metric has both practical and clinical significance. Most Bicycle Power Meters measure only the Average Angular Velocity (AAV) of the pedal throughout a given pedal stroke -- only a small number of power meters compute power using Instantaneous Angular Velocity (IAV). The paper highlights that power balance figures reported by devices employing these two methods have different physical meanings, and that AAV-based power balance figures will tend to be inaccurate when phase imbalance exists within a pedal stroke. Simulations were performed on a number of realistic indoor and outdoor riding scenarios. This results of this paper indicate that errors in Power Balance of up to 10% could occur under certain conditions., Comment: 13 pages, 4 figures

We present the Cosmic Piano, an innovative outreach tool designed to detect muons from air showers produced by cosmic rays colliding with the atmosphere. The Cosmic Piano consists of scintillator-based modules with avalanche photodiodes (APD) readout, which produce a musical note and a flash of light whenever a muon passes through one of them and triggers its electronics. The Cosmic Piano has been showcased at various high-profile events, including the Montreux Jazz Festival and the EuroScience Open Forum, seamlessly fusing scientific phenomena with live music. Building on its success, we have developed a new, comprehensive Masterclass session aimed at engaging high school and university students. This session includes analysing both simulated cosmic ray events and real data from the Cosmic Piano. The Masterclass provides participants with a hands-on experience that mirrors the experimental procedures used in major physics experiments, such as those conducted at CERN with the Large Hadron Collider (LHC) collision data. This initiative offers a unique opportunity for students to engage with an active experiment, bridging the gap between outreach and serious scientific research., Comment: 6 pages, 6 figures

Soon after the release of the WISE all-sky catalogue of 500 million mid-infrared (IR) objects, suggestions were made that it could be used to search for extrasolar devices constructed by an advanced civilization to convert a significant fraction of their host star's luminosity into useful work: "technostructures", "megastructures" or "Dyson spheres/structures", hereafter DSMs, whose inevitable waste heat would be seen by WISE at mid-IR wavelengths. However, a trawl of several million potentially-habitable Gaia-detected stars for mid-IR-excess signatures is fraught with danger, due to both noise from such a large sample and, more importantly, confusion with the emission from dusty background galaxies. In light of a recent claim of seven potential DSMs in MNRAS, a brief rebuttal appeared on arXiv. Further to this response, the relevance of WISE-detected galaxies is discussed in more detail, leading to a seemingly tight limit on the number and lifetime of DSMs, and indeed intelligent worlds, in the ~600-pc-radius region patrolled by Gaia. However, the detectability of DSMs is questioned: a DSM might extinguish its star at optical/near-IR wavelengths, and thus either not appear or appear anomalously faint in a stellar catalogue. Moreover, a civilization advanced enough to construct a DSM is likely to be advanced enough to use countermeasures to mask its presence from us., Comment: 6 pages. No figures. Submitted to MNRAS, possibly letters

Several studies have argued that the Milky Way was a representation of the ancient Egyptian sky goddess Nut. Here, I test this assumption by examining Nut's visual depictions on ancient Egyptian coffins. I assemble a catalog of 555 coffin elements, which includes 118 cosmological vignettes from the 21st/22nd Dynasties, and report several observations. First, I find that the cosmological vignette on the outer coffin of Nesitaudjatakhet bears a unique feature: a thick, undulating black curve that bisects Nut's star-studded body and recalls the Great Rift that cleaves the Milky Way in two. Moreover, it resembles similar features identified as the Milky Way on the bodies of Navajo, Hopi, and Zuni spiritual beings. Hence, I argue that the undulating curve on Nut's body is the first visual representation of the Milky Way identified in the Egyptian archaeological record. However, its rarity strengthens the conclusion reached by Graur (2024a): Though Nut and the Milky Way are linked, they are not synonymous. Instead of acting as a representation of Nut, the Milky Way is one more celestial phenomenon that, like the Sun and the stars, is associated with Nut in her role as the sky. Second, Nut's body is decorated with stars in only a quarter of the vignettes. If we associate Nut's naked and star-studded forms with the day and night sky, respectively, we would expect to see stars in half of the vignettes. This null hypothesis is rejected at $>6\sigma$ statistical significance. For whatever reason, it appears that the Egyptians of the 21st/22nd Dynasties preferred the day sky over the night sky. Finally, I discuss the interplay between Nut's cosmological vignette and full-length portraits inside coffins from the New Kingdom to the Roman Period in light of Nut's combined cosmological and eschatological roles as an embodiment of the coffin., Comment: 31 pages, 9 figures, 3 tables. Submitted to JAHH; comments welcome

We present a problem to be assigned or done as an in-class activity in an upper-division undergraduate course on computational physics. The problem involves a home run hit by Mickey Mantle on May 22, 1963, which he famously called ``the hardest ball I ever hit''. Is this home run truly one for the record books, or has it been eclipsed by players in the modern era? Modeling the trajectory of a baseball involves consideration of both wind resistance and the Magnus effect, and is an interesting application of numerical solution of ordinary differential equations. Ultimately, the answer is that Mantle would compare favorably to the most powerful batters currently playing, but to arrive at that conclusion we must reflect on the plausibility of results and sources of uncertainty., Comment: Accepted for publication in American Journal of Physics. 15 pages, 4 figures. Fig 1 licensed from Getty Images

Quantum Candies or Qandies provide us with a lucid way of understanding the concepts of quantum information and quantum science in the language of candies. The critical idea of qandies is intuitively depicting quantum science to the general public, making sense as most of the research in this domain is funded by the taxpayers. The qandies model is already used to explain the essential concepts of quantum science and quantum cryptography. However, teleportation and related concepts are yet to be explained. Motivated by this fact, we investigate and extend the idea of Jacobs and Lin-Mor-Shapira to explain teleportation using qandies. Here, we explicitly design the teleportation protocol and perform a circuit model using qandy gates. The protocol is successful when the correlated qandies are appropriately pre-shared and use of some local operations at both ends. The model we develop can be a valuable tool for science and engineering educators who want to help the general public to gain more insights into quantum science and technology., Comment: Quantum version of candies or qandies are used lucidly explain the concept of teleportation

This study uses methods from futures studies to develop a set of ten self-consistent scenarios for Earth's 1000-year future, which can serve as examples for defining technosignature search strategies. We apply a novel worldbuilding pipeline that evaluates the dimensions of human needs in each scenario as a basis for defining the observable properties of the technosphere. Our scenarios include three with zero-growth stability, two that have collapsed into a stable state, one that oscillates between growth and collapse, and four that continue to grow. Only one scenario includes rapid growth that could lead to interstellar expansion. We examine absorption spectral features for a few scenarios to illustrate that nitrogen dioxide can serve as a technosignature to distinguish between present-day Earth, pre-agricultural Earth, and an industrial 1000-year future Earth. Three of our scenarios are spectrally indistinguishable from pre-agricultural Earth, even though these scenarios include expansive technospheres. Up to nine of these scenarios could represent steady-state examples that could persist for much longer timescales, and it remains possible that short-duration technospheres could be the most abundant. Our scenario set provides the basis for further systematic thinking about technosignature detection as well as for imagining a broad range of possibilities for Earth's future., Comment: Submitted to Technological Forecasting and Social Change

Interview with prof. Tommaso Calarco from the Research Center J\"ulich (Germany) on Quantum Technologies and AI., Comment: 5 pages, 1 photo, Will be published in the Journal K\"unstliche Intelligenz, Vol.4, 2024, Springer

It was recently argued by Kemp et al. that HALEU (high-assay low-enriched uranium, or uranium enriched up to 19.75\%) can conceivably be used to produce a nuclear weapon and on this basis civilian enrichment limits should be lowered to 10% or 12%. We find their argument unconvincing in several respects., Comment: 5 pages, 1 figure

Since Galileo and (more recently) D'Arcy Thompson, it has been understood that physical processes and constraints influence biological structures and their resulting functions. However these cross-discpline connections -- and their importance to growing scientific discplines such as biophysics -- are rarely tought in introductory physics courses. Here we examine how the laws of physics shape Darwinism evolution through the surface area to volume ratio, an important geometric measure of a structure. We develop conceptual cartoon clicker questions to enhance students' understanding of these interdisciplinary concepts. By connecting abstract physical laws with biological (and technological) applications, our approach aims to help students appreciate the deep connections between physical and biological sciences, thereby enriching the learning experience in introductory physics courses., Comment: 31 page, 17 figures

Science Fiction is using astronomy to offer to the public blockbusters at the movies (e.g. Interstellar), series or movies in streaming media (Don't Look Up, The Expanse), many books from classic authors (I. Asimov, A.C. Clarke) or more modern ones (K.S. Robinson), comics (the adventures of Valerian and Laureline), or video games (Mass Effect, No Man's sky) that have a very large cumulated audience. Astronomers can use Science Fiction to illustrate physics or astronomical facts. It might be a good way to talk about our work, our methods, by comparing them to examples with which a large audience is familiar. A few examples are provided in this contribution. In a recent study (Stanwey, 2022), it was shown that 93 percent of British professional astronomers have an interest for Science Fiction, and 69 percent consider that Science Fiction influenced their career or life choice. I am presenting a similar study made for French astronomers, performed during and just after the 2024 French astronomer meeting (Journees de la SF2A)., Comment: Proceedings for the SF2A 2024 meeting - M. Bethermin, K. Bailli , N. Lagarde, J. Malzac, R.-M. Ouazzani, J. Richard, O. Venot, A. Siebert (eds)

One of the most popular movie franchises of late is Legendary's Monsterverse as is evidenced by the gross earnings of the series recently surpassing the two and a half billion dollar mark with the release of $\it{Godzilla X Kong}$. As is typical with many movies of this genre, in order to enjoy them one must suspend their disbelief when it comes to the laws of physics. While there are a plethora of examples of violations of basic principles (the square-cube law being the prime example) the idea of a "gravity inversion" occurring inside of the "Hollow Earth" is among the most debated as well as the most relevant to the storylines of the recent movies. The intent of this paper is to show that, while typical scientific arguments refuting the possibility of such an inversion are definitely completely correct, a slight modification of the conditions assumed to exist inside the planet in these arguments may allow for the inversion to actually occur., Comment: 4 pages, 2 figures

This introductory text on the basics of quantum mechanics is intended to serve as a kind of travel guide through the quantum world. It starts by asking whether quantum physics is important, or weird, or incomprehensible. It explains why particles sometimes behave like waves, and how uncertainty and randomness enter physics, before explaining a number of historically important experiments. Modern topics, like magnetic resonance imaging (MRI) and quantum computing are also covered. Essential concepts, such as the uncertainty principle, are analyzed in depth, employing a slightly increased dose of mathematics. This is the English version of the first part of a manual intended as a companion to the "Treffpunkt Quantenmechanik" (meeting point quantum mechanics), a laboratory at TU Dortmund University, where high-school students can get acquainted with the wonderful world of quantum physics. The second part of the manual contains detailed instructions for the individual experiments available in the lab and is not available on the Internet., Comment: 155 pages, popular text for high-school students

Designing for rotational stability can dramatically affect the geometry of a space station. If improperly designed, the rotating station could end up catastrophically tumbling end-over-end. Active stabilization can address this problem; however, designing the station with passive rotation stability provides a lower-cost solution. This paper presents passive rotational stability guidelines for four space station geometries. Station stability is first analyzed with thin-shell and thick-shell models. Stability is also analyzed with models of the station's major constituent parts, including outer shells, spokes, floors, air, and shuttle bays., Comment: 64 pages, 75 figures, 8 tables

As the space industry matures, large space stations will be built. This paper organizes and documents constraints on the size of these space stations. Human frailty, station design, and construction impose these constraints. Human limitations include gravity, radiation, air pressure, rotational stability, population, and psychology. Station design limitations include gravity, population, material, geometry, mass, air pressure, and rotational stability. Limits on space station construction include construction approaches, very large stations, and historic station examples. This paper documents all these constraints for thoroughness and review; however, only a few constraints significantly limit the station size. This paper considers rotating stations with radii greater than 10 kilometers. Such stations may seem absurd today; however, with robotic automation and artificial intelligence, such sizes may become feasible in the future., Comment: 65 Pages, 61 figures, 15 tables

The water bottle flip experiment is a recreational, non-conventional illustration of the conservation of angular moment. When a bottle partially filled with water is thrown in a rotational motion, water redistributes throughout the bottle, resulting in an increase of moment of inertia and thus to a decrease in angular velocity, which increases the probability of it falling upright on a table as compared with a bottle filled with ice. The investigation of this phenomenom is accessible to undergraduate students and should allow them to gain better understanding of combined translational and rotational motions in classical mechanics. In addition to reporting a series of detailed experiments and analyzing them using standard image analysis, we provide a simple theoretical framework and subsequent numerical implementation based on the decomposition of the water volume into thin slices of a rigid body that are subjected to fictitious forces in the non-inertial frame of the spinning bottle. This model allows us to capture quantitatively the main experimental findings, including the angular velocity slow-down for a given range of water filling fractions. Finally, we discuss additionnal counter-intuitive effects that contribute to bottle stabilization on landing.

The LIGO-Virgo-KAGRA (LVK) Collaboration has made breakthrough discoveries in gravitational-wave astronomy, a new field that provides a different means of observing our Universe. Gravitational-wave discoveries are possible thanks to the work of thousands of people from across the globe working together. In this article, we discuss the range of engagement activities used to communicate LVK gravitational-wave discoveries and the stories of the people behind the science, using the activities surrounding the release of the third Gravitational-Wave Transient Catalog as a case study., Comment: 15 pages, 7 figures, published in JCOM: https://doi.org/10.22323/2.23070803

The Special Theory of Relativity, introduced by Albert Einstein in the early 20th century, marked a radical shift in our understanding of space and time. Nevertheless, the theory's non-intuitive implications continue to pose conceptual challenges for novice physicists. In this thesis, we propose a virtual reality solution based on the development of a Unity package capable of simulating the effects of relativity in a digital environment. The current implementation includes the representation of space contraction, time dilation and relativistic Doppler effect. The primary focus lies in the accurate representation of relativistic laws, as well as in computational efficiency and in the modeling of a user interface specifically crafted to enhance understanding and interactivity. The package significantly reduces developer workload through a streamlined API, enabling maximum freedom in the development of virtual scenarios. Design goals are validated by a testing phase conducted through dedicated probe scenes. To showcase the potential of this work, we also present the deployment of a VR application built on top of the package, that transports users in experiencing relativistic effects in real-life scenarios. The application is scheduled to be used by Master's students in Physical Engineering at Politecnico di Milano. In the meanwhile, other educational areas of expansion are being considered, suggesting a promising future in the direction of this work.

In the course of the energy transition, energy generation from nuclear power - through nuclear fission and perhaps in the future through nuclear fusion - is often proposed as an alternative or supplement to renewable energy sources. There are already good reasons why electricity generation from nuclear energy is significantly more expensive than other forms of generation, while increasing dryness as a result of climate change is generally calling into question the reliability of thermal power plants. Nuclear energy is therefore unlikely to play a role in a future energy supply that relies on low costs and reliability., Comment: 13 pages, 6 figures. Physik in unserer Zeit, available online (2024)

Gravitational waves are oscillations of space-time that are created, for example, in black hole mergers. If these waves travel through another massive astrophysical object, they will undergo an effect called gravitational lensing, that will distort and deflect them. This effect can create multiple images of the gravitational wave signal, and interference between them. In this document, we describe the sonification process of the gravitational lensing effect on gravitational waves. Sonification is the translation of data into sound. The wave nature of sound creates interference between waves in a natural way. This has allowed us to reproduce the interference produced by the superposition of gravitational wave images, characteristic of the gravitational lensing effect. The results can be heard on the following websites: https://zoom3.net/sonificacions/ona-gravitacional.html - gravitational waves from the merger of two black holes https://zoom3.net/sonificacions/ona-gravitacional-lent.html - gravitational waves affected by a gravitational lens, interactive website https://zoom3.net/sonificacions/ona-gravitacional-lent-exemples.html - gravitational waves affected by a gravitational lens, recorded examples., Comment: 23 pages in total. The document is written in both English and Catalan versions (10 pages, 4 figures each)

The speed-accuracy tradeoffs are prevalent in a wide range of physical systems. In this paper, we demonstrate speed-accuracy tradeoffs in the game of cricket, where 'batters' score runs on the balls bowled by the 'bowlers'. It is shown that the run scoring rate by a batter and the probability of dismissal follow a power-law relation. Due to availability of extensive data, game of cricket is an excellent model for the study of the effect of speed-accuracy tradeoff on the overall performance of the system. It is shown that the exponent of the power-law governs the nature of the adaptability of the player in different conditions and can be used for their assessment. Further, it is demonstrated that the players with extreme values of the power-law exponent are better suited for different playing conditions as compared to the ones with moderate values. These findings can be utilized to identify the potential of the cricket players for different game formats and can further help team management in devising strategies for the best outcomes with a given set of players., Comment: 6 pages, 3 figures

Given an appetizer bowl full of $N$ pistachios, what is the optimal size of the container -- neither too small, nor too big -- needed for accommodating the resulting $2N$ non-edible pistachio shells? Performing a simple experiment we find that, provided the shells are densely packed, such container needs only be slightly more than half ($\approx 0.57$) that of the original pistachio bowl. If loosely packed this number increases to $\approx 0.73$. Our results are discussed in light of existing literature on packing ellipsoids and spherical caps., Comment: 3 pages, 4 figures

Peter Higgs was a British theoretical physicist, famous for his work published in 1964, where he proposed a mechanism that can generate masses for elementary particles, while respecting gauge invariance. Half a century later, two experiments at CERN confirmed that this mechanism is realized in nature. On April 8th, we received the sad news of the passing of the great pioneer of elementary particle physics. This article is dedicated to his memory, and to the mechanism and particle that bear his name. -- Peter Higgs fue un f\'isico te\'orico brit\'anico, famoso por su trabajo de 1964 donde propuso un mecanismo que puede generar masas para part\'iculas elementales, conforme a la simetr\'ia de norma. Medio siglo m\'as tarde, dos experimentos del CERN confirmaron que este mecanismo est\'a realizado en la naturaleza. El 8 de abril nos lleg\'o la triste noticia del fallecimiento del gran pionero de la fisica de part\'iculas elementales. Este art\'iculo es dedicado a su memoria, as\'i como al mecanismo y a la part\'icula que llevan su nombre., Comment: 15 pages, LaTex, 13 figures, bilingual: English version to be published in Rev. Cub. F\'is., Spanish version to be published in Bol. Soc. Mex. F\'is

In this article we pay tribute to Herbert Dingle for his early call to re-assess special relativity from philosophical and logical perspectives. However, we disagree with Dingle about a number of issues particularly his failure to distinguish between the scientific essence of special relativity (as represented by the experimentally-supported Lorentz transformations and their formal implications and consequences which we call "the mechanics of Lorentz transformations") and the logically inconsistent interpretation of Einstein (which is largely based on the philosophical and epistemological views of Poincare). We also disagree with him about his manner and attitude which he adopted in his campaign against special relativity although we generally agree with him about the necessity of impartiality of the scientific community and the scientific press towards scientific theories and opinions as well as the necessity of total respect to the ethics of science and the rules of moral conduct in general., Comment: 15 pages

In ecological systems, be it a garden or a galaxy, populations evolve from some initial value (say zero) up to a steady state equilibrium, when the mean number of births and deaths per unit time are equal. This equilibrium point is a function of the birth and death rates, as well as the carrying capacity of the ecological system itself. The growth curve is S-shaped, saturating at the carrying capacity for large birth-to-death rate ratios and tending to zero at the other end. We argue that our astronomical observations appear inconsistent with a cosmos saturated with ETIs, and thus SETI optimists are left presuming that the true population is somewhere along the transitional part of this S-curve. Since the birth and death rates are a-priori unbounded, we argue that this presents a fine-tuning problem. Further, we show that if the birth-to-death rate ratio is assumed to have a log-uniform prior distribution, then the probability distribution of the ecological filling fraction is bi-modal - peaking at zero and unity. Indeed, the resulting distribution is formally the classic Haldane prior, conceived to describe the prior expectation of a Bernoulli experiment, such as a technological intelligence developing (or not) on a given world. Our results formally connect the Drake Equation to the birth-death formalism, the treatment of ecological carrying capacity and their connection to the Haldane perspective., Comment: Submitted to IJA

The momentum of human spaceflight initiatives continues to build toward Mars, and technological advances may eventually enable the potential for permanent space settlement. Aspirations for sustaining human life in space must be predicated on human factors, rather than technological constraints alone, and advances in models of governance and ethics are necessary as human civilization becomes a spacefaring species. This paper presents an idealistic but feasible model for economic freedom on Mars, which is situated within a framework in which Mars has been designated as a sovereign juridical peer to Earth. Under such conditions, Mars could maintain monetary stability through full reserve banking and a restriction on exchange with any fractional reserve Earth currencies, with a volume of circulating currency that changes based on the total population within fixed capacity infrastructure. Mars could maintain long-term political stability by diffusing the ownership of capital on Mars, which would allow all citizens of Mars to draw sufficient wealth from a combination of capital ownership and labor to live a good life. This model could also support limited tourism on Mars, in which real goods are exchanged for services but currency transactions between planets are prohibited. This model demonstrates the potential for a viable and sustainable economy on Mars that could conceivably be implemented, including on a sovereign Mars but also in other scenarios of space settlement. More broadly, this model illustrates that ideas such as diffuse capital ownership and limited government can enable freedom in space, and numerous models beyond a centralized world space agency should be explored to ensure the optimal governance of the emerging space economy., Comment: Accepted by Space Policy