This document discusses the different types of motion: straight motion occurs when something moves in a straight line, circular motion is when something moves in a circle, and back and forth motion involves moving back and forth along the same path.
This document discusses the concept of inertia. It defines inertia as an object's tendency to remain at rest or in motion unless acted upon by an external force. It explains that inertia is influenced by mass, with more massive objects having greater inertia. Examples are given of how inertia causes objects and passengers in moving vehicles to continue moving when motion stops suddenly without external forces like seatbelts intervening. Safety measures in vehicles are described that counteract the negative effects of inertia during sudden stops.
My science project is about recycling and how it helps the environment. I will research how recycling reduces waste sent to landfills and conserves natural resources. I plan to collect recycling from my school and neighborhood for a week and analyze what materials are most commonly recycled to show how it makes a difference.
The document discusses different aspects of motion including that motion refers to something that is moving, objects can move at different speeds, and things may move in straight, curved, circular or zigzag paths. It also reviews key ideas like how to determine if one object is moving faster than another and different ways that speed and motion are defined.
This document discusses different types of motion. It defines motion as a change in an object's position over time and notes that motion is always observed relative to a reference point. It then outlines the main types of motion as translatory, circular, random, oscillatory, vibratory, and periodic motion. Translatory motion is described as uniform motion in a straight line and can be rectilinear or curvilinear. Circular motion involves moving around a fixed axis, with examples given of revolution and rotatory motion. Several everyday objects and actions demonstrating multiple types of motion are provided.
This document provides an overview of key concepts related to force and motion, including definitions and formulas. It defines a force as a push or pull and notes they have both size and direction. It explains net forces result from combining multiple forces and discusses balanced and unbalanced forces. Key terms like motion, speed, velocity, acceleration, inertia, and Newton's Three Laws of Motion are defined. Formulas for speed, acceleration, weight, and examples of applications of the three laws are also presented.
This document discusses the concept of inertia. It defines inertia as an object's tendency to remain at rest or in motion unless acted upon by an external force. It explains that inertia is influenced by mass, with more massive objects having greater inertia. Examples are given of how inertia causes objects and passengers in moving vehicles to continue moving when motion stops suddenly without external forces like seatbelts intervening. Safety measures in vehicles are described that counteract the negative effects of inertia during sudden stops.
My science project is about recycling and how it helps the environment. I will research how recycling reduces waste sent to landfills and conserves natural resources. I plan to collect recycling from my school and neighborhood for a week and analyze what materials are most commonly recycled to show how it makes a difference.
The document discusses different aspects of motion including that motion refers to something that is moving, objects can move at different speeds, and things may move in straight, curved, circular or zigzag paths. It also reviews key ideas like how to determine if one object is moving faster than another and different ways that speed and motion are defined.
This document discusses different types of motion. It defines motion as a change in an object's position over time and notes that motion is always observed relative to a reference point. It then outlines the main types of motion as translatory, circular, random, oscillatory, vibratory, and periodic motion. Translatory motion is described as uniform motion in a straight line and can be rectilinear or curvilinear. Circular motion involves moving around a fixed axis, with examples given of revolution and rotatory motion. Several everyday objects and actions demonstrating multiple types of motion are provided.
This document provides an overview of key concepts related to force and motion, including definitions and formulas. It defines a force as a push or pull and notes they have both size and direction. It explains net forces result from combining multiple forces and discusses balanced and unbalanced forces. Key terms like motion, speed, velocity, acceleration, inertia, and Newton's Three Laws of Motion are defined. Formulas for speed, acceleration, weight, and examples of applications of the three laws are also presented.
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive function. Exercise causes chemical changes in the brain that may help protect against developing mental illness and improve symptoms for those who already suffer from conditions like anxiety and depression.
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive functioning. Exercise causes chemical changes in the brain that may help boost feelings of calmness, happiness and focus.
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive function. Exercise causes chemical changes in the brain that may help protect against mental illness and improve symptoms.
Poles are the points on Earth where the axis of rotation meets the surface. The north pole is located in the Arctic and the south pole is located in Antarctica. Magnets have poles that attract or repel other magnets and objects, and a compass needle points north because of Earth's magnetic field and poles.
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive function. Exercise causes chemical changes in the brain that may help protect against mental illness and improve symptoms for those who already suffer from conditions like anxiety and depression.
The flowering plant life cycle begins with a seed that germinates when it receives water and heat, sprouting into a seedling. The seedling grows into an adult plant with roots, stem, leaves, and flowers. Pollen moves between flowers via bees, water, wind, and other animals, fertilizing the flowers and causing them to develop into fruits containing new seeds, completing the cycle to begin anew.
The butterfly goes through distinct life cycle stages of egg, caterpillar, pupa, and adult butterfly. The egg hatches into a caterpillar that eats leaves to grow large, then forms a hard shell called a pupa where it transforms into an adult butterfly, which emerges from the pupa fully formed to complete the cycle.
White-tailed deer have a life cycle where fawns are born and drink milk from their mothers to grow. The fawns then become yearlings after one year, still resembling the mother. Finally, the yearlings mature into adult deer after further growth.
The earth changes slowly through natural processes like moving water, wind, and ice. Moving water and wind can break down and carry away rocks and soil. Ice forms in cracks in rocks when water freezes, and the expansion of freezing water pushes rocks further apart, breaking them down over time.
The document discusses four ways the earth changes quickly: volcanoes erupt very hot liquid from openings at the top of mountains; earthquakes occur when the earth's layers shake; floods result when heavy rain falls and water covers the ground; and landslides happen when land and rocks fall from high to low places.
The document discusses different adaptations that animals use to stay safe and prepare for seasonal changes. It explains that tuna fish stay in groups for protection, and in fall animals adapt to the cooling weather and get ready for winter through behaviors like hibernation where they sleep through winter, and migration where some animals like birds and fish live in warmer places during fall and winter before returning in spring.
Fall is characterized by cool weather and wind, prompting people to wear long sleeves and pants. People also enjoy playing in piles of fallen leaves during this season. In summary, fall brings changing weather and opportunities to enjoy the outdoors while bundling up.
Anti-Universe And Emergent Gravity and the Dark UniverseSérgio Sacani
Recent theoretical progress indicates that spacetime and gravity emerge together from the entanglement structure of an underlying microscopic theory. These ideas are best understood in Anti-de Sitter space, where they rely on the area law for entanglement entropy. The extension to de Sitter space requires taking into account the entropy and temperature associated with the cosmological horizon. Using insights from string theory, black hole physics and quantum information theory we argue that the positive dark energy leads to a thermal volume law contribution to the entropy that overtakes the area law precisely at the cosmological horizon. Due to the competition between area and volume law entanglement the microscopic de Sitter states do not thermalise at sub-Hubble scales: they exhibit memory effects in the form of an entropy displacement caused by matter. The emergent laws of gravity contain an additional ‘dark’ gravitational force describing the ‘elastic’ response due to the entropy displacement. We derive an estimate of the strength of this extra force in terms of the baryonic mass, Newton’s constant and the Hubble acceleration scale a0 = cH0, and provide evidence for the fact that this additional ‘dark gravity force’ explains the observed phenomena in galaxies and clusters currently attributed to dark matter.
Embracing Deep Variability For Reproducibility and Replicability
Abstract: Reproducibility (aka determinism in some cases) constitutes a fundamental aspect in various fields of computer science, such as floating-point computations in numerical analysis and simulation, concurrency models in parallelism, reproducible builds for third parties integration and packaging, and containerization for execution environments. These concepts, while pervasive across diverse concerns, often exhibit intricate inter-dependencies, making it challenging to achieve a comprehensive understanding. In this short and vision paper we delve into the application of software engineering techniques, specifically variability management, to systematically identify and explicit points of variability that may give rise to reproducibility issues (eg language, libraries, compiler, virtual machine, OS, environment variables, etc). The primary objectives are: i) gaining insights into the variability layers and their possible interactions, ii) capturing and documenting configurations for the sake of reproducibility, and iii) exploring diverse configurations to replicate, and hence validate and ensure the robustness of results. By adopting these methodologies, we aim to address the complexities associated with reproducibility and replicability in modern software systems and environments, facilitating a more comprehensive and nuanced perspective on these critical aspects.
https://hal.science/hal-04582287
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive function. Exercise causes chemical changes in the brain that may help protect against developing mental illness and improve symptoms for those who already suffer from conditions like anxiety and depression.
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive functioning. Exercise causes chemical changes in the brain that may help boost feelings of calmness, happiness and focus.
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive function. Exercise causes chemical changes in the brain that may help protect against mental illness and improve symptoms.
Poles are the points on Earth where the axis of rotation meets the surface. The north pole is located in the Arctic and the south pole is located in Antarctica. Magnets have poles that attract or repel other magnets and objects, and a compass needle points north because of Earth's magnetic field and poles.
The document discusses the benefits of exercise for mental health. Regular physical activity can help reduce anxiety and depression and improve mood and cognitive function. Exercise causes chemical changes in the brain that may help protect against mental illness and improve symptoms for those who already suffer from conditions like anxiety and depression.
The flowering plant life cycle begins with a seed that germinates when it receives water and heat, sprouting into a seedling. The seedling grows into an adult plant with roots, stem, leaves, and flowers. Pollen moves between flowers via bees, water, wind, and other animals, fertilizing the flowers and causing them to develop into fruits containing new seeds, completing the cycle to begin anew.
The butterfly goes through distinct life cycle stages of egg, caterpillar, pupa, and adult butterfly. The egg hatches into a caterpillar that eats leaves to grow large, then forms a hard shell called a pupa where it transforms into an adult butterfly, which emerges from the pupa fully formed to complete the cycle.
White-tailed deer have a life cycle where fawns are born and drink milk from their mothers to grow. The fawns then become yearlings after one year, still resembling the mother. Finally, the yearlings mature into adult deer after further growth.
The earth changes slowly through natural processes like moving water, wind, and ice. Moving water and wind can break down and carry away rocks and soil. Ice forms in cracks in rocks when water freezes, and the expansion of freezing water pushes rocks further apart, breaking them down over time.
The document discusses four ways the earth changes quickly: volcanoes erupt very hot liquid from openings at the top of mountains; earthquakes occur when the earth's layers shake; floods result when heavy rain falls and water covers the ground; and landslides happen when land and rocks fall from high to low places.
The document discusses different adaptations that animals use to stay safe and prepare for seasonal changes. It explains that tuna fish stay in groups for protection, and in fall animals adapt to the cooling weather and get ready for winter through behaviors like hibernation where they sleep through winter, and migration where some animals like birds and fish live in warmer places during fall and winter before returning in spring.
Fall is characterized by cool weather and wind, prompting people to wear long sleeves and pants. People also enjoy playing in piles of fallen leaves during this season. In summary, fall brings changing weather and opportunities to enjoy the outdoors while bundling up.
Anti-Universe And Emergent Gravity and the Dark UniverseSérgio Sacani
Recent theoretical progress indicates that spacetime and gravity emerge together from the entanglement structure of an underlying microscopic theory. These ideas are best understood in Anti-de Sitter space, where they rely on the area law for entanglement entropy. The extension to de Sitter space requires taking into account the entropy and temperature associated with the cosmological horizon. Using insights from string theory, black hole physics and quantum information theory we argue that the positive dark energy leads to a thermal volume law contribution to the entropy that overtakes the area law precisely at the cosmological horizon. Due to the competition between area and volume law entanglement the microscopic de Sitter states do not thermalise at sub-Hubble scales: they exhibit memory effects in the form of an entropy displacement caused by matter. The emergent laws of gravity contain an additional ‘dark’ gravitational force describing the ‘elastic’ response due to the entropy displacement. We derive an estimate of the strength of this extra force in terms of the baryonic mass, Newton’s constant and the Hubble acceleration scale a0 = cH0, and provide evidence for the fact that this additional ‘dark gravity force’ explains the observed phenomena in galaxies and clusters currently attributed to dark matter.
Embracing Deep Variability For Reproducibility and Replicability
Abstract: Reproducibility (aka determinism in some cases) constitutes a fundamental aspect in various fields of computer science, such as floating-point computations in numerical analysis and simulation, concurrency models in parallelism, reproducible builds for third parties integration and packaging, and containerization for execution environments. These concepts, while pervasive across diverse concerns, often exhibit intricate inter-dependencies, making it challenging to achieve a comprehensive understanding. In this short and vision paper we delve into the application of software engineering techniques, specifically variability management, to systematically identify and explicit points of variability that may give rise to reproducibility issues (eg language, libraries, compiler, virtual machine, OS, environment variables, etc). The primary objectives are: i) gaining insights into the variability layers and their possible interactions, ii) capturing and documenting configurations for the sake of reproducibility, and iii) exploring diverse configurations to replicate, and hence validate and ensure the robustness of results. By adopting these methodologies, we aim to address the complexities associated with reproducibility and replicability in modern software systems and environments, facilitating a more comprehensive and nuanced perspective on these critical aspects.
https://hal.science/hal-04582287
SDSS1335+0728: The awakening of a ∼ 106M⊙ black hole⋆Sérgio Sacani
Context. The early-type galaxy SDSS J133519.91+072807.4 (hereafter SDSS1335+0728), which had exhibited no prior optical variations during the preceding two decades, began showing significant nuclear variability in the Zwicky Transient Facility (ZTF) alert stream from December 2019 (as ZTF19acnskyy). This variability behaviour, coupled with the host-galaxy properties, suggests that SDSS1335+0728 hosts a ∼ 106M⊙ black hole (BH) that is currently in the process of ‘turning on’. Aims. We present a multi-wavelength photometric analysis and spectroscopic follow-up performed with the aim of better understanding the origin of the nuclear variations detected in SDSS1335+0728. Methods. We used archival photometry (from WISE, 2MASS, SDSS, GALEX, eROSITA) and spectroscopic data (from SDSS and LAMOST) to study the state of SDSS1335+0728 prior to December 2019, and new observations from Swift, SOAR/Goodman, VLT/X-shooter, and Keck/LRIS taken after its turn-on to characterise its current state. We analysed the variability of SDSS1335+0728 in the X-ray/UV/optical/mid-infrared range, modelled its spectral energy distribution prior to and after December 2019, and studied the evolution of its UV/optical spectra. Results. From our multi-wavelength photometric analysis, we find that: (a) since 2021, the UV flux (from Swift/UVOT observations) is four times brighter than the flux reported by GALEX in 2004; (b) since June 2022, the mid-infrared flux has risen more than two times, and the W1−W2 WISE colour has become redder; and (c) since February 2024, the source has begun showing X-ray emission. From our spectroscopic follow-up, we see that (i) the narrow emission line ratios are now consistent with a more energetic ionising continuum; (ii) broad emission lines are not detected; and (iii) the [OIII] line increased its flux ∼ 3.6 years after the first ZTF alert, which implies a relatively compact narrow-line-emitting region. Conclusions. We conclude that the variations observed in SDSS1335+0728 could be either explained by a ∼ 106M⊙ AGN that is just turning on or by an exotic tidal disruption event (TDE). If the former is true, SDSS1335+0728 is one of the strongest cases of an AGNobserved in the process of activating. If the latter were found to be the case, it would correspond to the longest and faintest TDE ever observed (or another class of still unknown nuclear transient). Future observations of SDSS1335+0728 are crucial to further understand its behaviour. Key words. galaxies: active– accretion, accretion discs– galaxies: individual: SDSS J133519.91+072807.4
Dr. Firoozeh Kashani-Sabet is an innovator in Middle Eastern Studies and approaches her work, particularly focused on Iran, with a depth and commitment that has resulted in multiple book publications. She is notable for her work with the University of Pennsylvania, where she serves as the Walter H. Annenberg Professor of History.
Mechanics:- Simple and Compound PendulumPravinHudge1
a compound pendulum is a physical system with a more complex structure than a simple pendulum, incorporating its mass distribution and dimensions into its oscillatory motion around a fixed axis. Understanding its dynamics involves principles of rotational mechanics and the interplay between gravitational potential energy and kinetic energy. Compound pendulums are used in various scientific and engineering applications, such as seismology for measuring earthquakes, in clocks to maintain accurate timekeeping, and in mechanical systems to study oscillatory motion dynamics.
JAMES WEBB STUDY THE MASSIVE BLACK HOLE SEEDSSérgio Sacani
The pathway(s) to seeding the massive black holes (MBHs) that exist at the heart of galaxies in the present and distant Universe remains an unsolved problem. Here we categorise, describe and quantitatively discuss the formation pathways of both light and heavy seeds. We emphasise that the most recent computational models suggest that rather than a bimodal-like mass spectrum between light and heavy seeds with light at one end and heavy at the other that instead a continuum exists. Light seeds being more ubiquitous and the heavier seeds becoming less and less abundant due the rarer environmental conditions required for their formation. We therefore examine the different mechanisms that give rise to different seed mass spectrums. We show how and why the mechanisms that produce the heaviest seeds are also among the rarest events in the Universe and are hence extremely unlikely to be the seeds for the vast majority of the MBH population. We quantify, within the limits of the current large uncertainties in the seeding processes, the expected number densities of the seed mass spectrum. We argue that light seeds must be at least 103 to 105 times more numerous than heavy seeds to explain the MBH population as a whole. Based on our current understanding of the seed population this makes heavy seeds (Mseed > 103 M⊙) a significantly more likely pathway given that heavy seeds have an abundance pattern than is close to and likely in excess of 10−4 compared to light seeds. Finally, we examine the current state-of-the-art in numerical calculations and recent observations and plot a path forward for near-future advances in both domains.
Candidate young stellar objects in the S-cluster: Kinematic analysis of a sub...Sérgio Sacani
Context. The observation of several L-band emission sources in the S cluster has led to a rich discussion of their nature. However, a definitive answer to the classification of the dusty objects requires an explanation for the detection of compact Doppler-shifted Brγ emission. The ionized hydrogen in combination with the observation of mid-infrared L-band continuum emission suggests that most of these sources are embedded in a dusty envelope. These embedded sources are part of the S-cluster, and their relationship to the S-stars is still under debate. To date, the question of the origin of these two populations has been vague, although all explanations favor migration processes for the individual cluster members. Aims. This work revisits the S-cluster and its dusty members orbiting the supermassive black hole SgrA* on bound Keplerian orbits from a kinematic perspective. The aim is to explore the Keplerian parameters for patterns that might imply a nonrandom distribution of the sample. Additionally, various analytical aspects are considered to address the nature of the dusty sources. Methods. Based on the photometric analysis, we estimated the individual H−K and K−L colors for the source sample and compared the results to known cluster members. The classification revealed a noticeable contrast between the S-stars and the dusty sources. To fit the flux-density distribution, we utilized the radiative transfer code HYPERION and implemented a young stellar object Class I model. We obtained the position angle from the Keplerian fit results; additionally, we analyzed the distribution of the inclinations and the longitudes of the ascending node. Results. The colors of the dusty sources suggest a stellar nature consistent with the spectral energy distribution in the near and midinfrared domains. Furthermore, the evaporation timescales of dusty and gaseous clumps in the vicinity of SgrA* are much shorter ( 2yr) than the epochs covered by the observations (≈15yr). In addition to the strong evidence for the stellar classification of the D-sources, we also find a clear disk-like pattern following the arrangements of S-stars proposed in the literature. Furthermore, we find a global intrinsic inclination for all dusty sources of 60 ± 20◦, implying a common formation process. Conclusions. The pattern of the dusty sources manifested in the distribution of the position angles, inclinations, and longitudes of the ascending node strongly suggests two different scenarios: the main-sequence stars and the dusty stellar S-cluster sources share a common formation history or migrated with a similar formation channel in the vicinity of SgrA*. Alternatively, the gravitational influence of SgrA* in combination with a massive perturber, such as a putative intermediate mass black hole in the IRS 13 cluster, forces the dusty objects and S-stars to follow a particular orbital arrangement. Key words. stars: black holes– stars: formation– Galaxy: center– galaxies: star formation
Evidence of Jet Activity from the Secondary Black Hole in the OJ 287 Binary S...Sérgio Sacani
Wereport the study of a huge optical intraday flare on 2021 November 12 at 2 a.m. UT in the blazar OJ287. In the binary black hole model, it is associated with an impact of the secondary black hole on the accretion disk of the primary. Our multifrequency observing campaign was set up to search for such a signature of the impact based on a prediction made 8 yr earlier. The first I-band results of the flare have already been reported by Kishore et al. (2024). Here we combine these data with our monitoring in the R-band. There is a big change in the R–I spectral index by 1.0 ±0.1 between the normal background and the flare, suggesting a new component of radiation. The polarization variation during the rise of the flare suggests the same. The limits on the source size place it most reasonably in the jet of the secondary BH. We then ask why we have not seen this phenomenon before. We show that OJ287 was never before observed with sufficient sensitivity on the night when the flare should have happened according to the binary model. We also study the probability that this flare is just an oversized example of intraday variability using the Krakow data set of intense monitoring between 2015 and 2023. We find that the occurrence of a flare of this size and rapidity is unlikely. In machine-readable Tables 1 and 2, we give the full orbit-linked historical light curve of OJ287 as well as the dense monitoring sample of Krakow.