Stories with Tag Earth's Rotation

• Can Earth's rotation generate power? Physicists divided over controversial claim

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  Posted: 2025-03-30 18:41:46

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  A recent paper claims Earth's rotation could be harnessed for power using a "gravity engine," theoretically generating terawatts of energy by raising and lowering massive weights as the Earth rotates. This concept, building on decades-old physics, hinges on the Coriolis effect. However, many physicists are skeptical, arguing that the proposed mechanism violates fundamental laws of physics, particularly conservation of angular momentum. They contend that any energy gained would be offset by a minuscule slowing of Earth's rotation, effectively transferring rotational energy rather than creating it. The debate highlights the complex interplay between gravity, rotation, and energy, with the practicality and feasibility of such a gravity engine remaining highly contested.

  A recent scientific discourse has ignited a debate within the physics community regarding the potential to harness energy from the Earth's rotation. The central argument revolves around a proposed device, conceived by researchers at the U.S. Army Engineer Research and Development Center, which seeks to exploit the Coriolis force, an inertial effect observed in rotating reference frames like our planet. This force, responsible for the deflection of moving objects (like air currents and projectiles) to the right in the Northern Hemisphere and to the left in the Southern Hemisphere, is typically considered a "fictitious force" in classical mechanics, meaning it arises from the frame of reference itself rather than a direct physical interaction.

  The proposed mechanism, as detailed in the researchers' published work, envisions a large, rotating platform analogous to a carousel. Theoretically, by carefully controlling the angular velocity of this platform relative to the Earth’s rotation, one could potentially generate usable energy from the interaction with the Coriolis force. This concept, while seemingly intriguing, has drawn considerable skepticism from other physicists who argue that the Coriolis force is not a true source of energy but rather a consequence of the Earth’s rotational inertia. They contend that any apparent energy extracted from the Coriolis effect would, in reality, be derived from the energy required to maintain the rotation of the platform itself, ultimately resulting in a zero-sum or even negative energy gain when accounting for system losses.

  The core of the disagreement stems from differing interpretations of the Coriolis force and its role in energy transfer. Proponents of the energy-harvesting concept posit that the Earth’s rotation represents a vast reservoir of kinetic energy, a portion of which could be tapped into via a cleverly engineered device. Their calculations suggest that under specific conditions, the Coriolis force could induce a net torque on the rotating platform, thereby generating mechanical energy. However, critics argue that this interpretation misrepresents the fundamental nature of the Coriolis force. They maintain that while the Coriolis force can influence the motion of objects within a rotating frame, it cannot perform work in the same way as a true force like gravity or electromagnetism. Therefore, they argue, any attempt to extract energy from the Coriolis effect would be analogous to attempting to extract energy from inertia itself, a fundamentally flawed proposition.

  The ongoing debate highlights the complexities of understanding and applying fundamental physical principles, particularly in rotating reference frames. While the possibility of harnessing the Earth’s rotation for energy generation remains a tantalizing prospect, the current consensus within the physics community leans towards skepticism. Further research and rigorous experimental validation are necessary to definitively settle the controversy and determine the true potential, if any, of this novel approach to energy harvesting.

  • Earth's Rotation
  • Energy Generation
  • physics
  • Geophysics
  • Controversial Claim
  • scientific debate
  • renewable energy
  • Rotational Energy
  • Nature (Journal)
  • scientific research
  • earth science

  Summary of Comments ( 130 )
  https://news.ycombinator.com/item?id=43526443

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  Hacker News users discuss a Nature article about a controversial claim that Earth's rotation could be harnessed for power. Several commenters express skepticism, pointing to the immense scale and impracticality of such a project, even if theoretically possible. Some highlight the conservation of angular momentum, arguing that extracting energy from Earth's rotation would necessarily slow it down, albeit imperceptibly. Others debate the interpretation of the original research, with some suggesting it's more about subtle gravitational effects than a large-scale power source. A few commenters mention existing technologies that indirectly utilize Earth's rotation, such as tidal power. The overall sentiment seems to be one of cautious curiosity mixed with doubt about the feasibility and significance of the proposed concept. A few users engage in more playful speculation, imagining the distant future where such technology might be relevant.

  The Hacker News post "Can Earth's rotation generate power? Physicists divided over controversial claim" sparked a discussion with several interesting comments. Many commenters engaged with the core concept of extracting energy from Earth's rotation, exploring its theoretical feasibility and practical implications.

  Several commenters pointed out the existing methods of harnessing energy derived from Earth's rotation, primarily through tidal power. Tides are a direct consequence of the gravitational interaction between Earth, the Moon, and the Sun, and their cyclical nature allows for predictable energy generation. This led to discussions about the distinction between directly tapping into rotational energy versus utilizing its indirect effects.

  Some users questioned the novelty of the proposed mechanism in the linked Nature article, arguing that any method of extracting energy from Earth's rotation would necessarily involve interaction with another celestial body, thereby slowing Earth's rotation. They emphasized the fundamental principle of conservation of angular momentum, implying that extracting usable energy would require transferring some angular momentum away from the Earth.

  A significant point of contention revolved around the scale of energy that could realistically be extracted and its impact on Earth's rotation. Some commenters expressed skepticism about the practicality of generating substantial power without causing significant, albeit extremely gradual, changes to the length of a day.

  A few commenters delved into more technical aspects, referencing concepts like Lenz's law and the inherent inefficiencies involved in energy conversion processes. They also discussed the potential environmental impact of any large-scale attempt to harness rotational energy.

  Finally, some users expressed a general sense of caution regarding sensationalized scientific claims, emphasizing the importance of peer review and rigorous validation before drawing definitive conclusions. They also highlighted the difference between theoretical possibilities and practical, economically viable implementations.

• Earth's inner core may have changed shape, say scientists

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  Posted: 2025-02-10 16:31:59

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  Scientists studying seismic waves traveling through the Earth's core have found evidence suggesting the inner core's growth isn't uniform. Analysis indicates the eastern hemisphere of the inner core under Indonesia's Banda Sea is growing faster than the western hemisphere under Brazil. This asymmetrical growth may be influencing the Earth's magnetic field, as the inner core's crystallization releases heat that drives the churning motion of the outer core, responsible for generating the field. While the exact mechanisms and implications remain uncertain, this research offers new insights into the complex dynamics deep within our planet.

  In a recent development within the realm of geophysics, a study published in the esteemed journal Nature Geoscience suggests a potentially significant alteration in the behavior of Earth's inner core. Researchers, employing the meticulous analysis of seismic wave data spanning several decades, have postulated that the innermost sphere of our planet, a solid iron-nickel alloy subjected to immense pressure and temperature, may be experiencing a shift in its rotational characteristics relative to the Earth's mantle and crust.

  Traditionally, it has been understood that the Earth's inner core rotates at a slightly faster rate than the rest of the planet, a phenomenon known as super-rotation. This differential rotation is attributed to the complex interplay of electromagnetic forces and gravitational torques within the Earth's deep interior. However, the new research indicates that this super-rotation may have recently paused, or even potentially reversed, around the year 2009. This observation is based on subtle variations in the travel times of seismic waves that traverse the planet's core, offering a glimpse into the hidden dynamics at play thousands of kilometers beneath our feet.

  The ramifications of this potential shift in inner core rotation are still under intense scrutiny by the scientific community. While the changes are subtle and do not pose an immediate threat to life on Earth, they could have implications for our understanding of the planet's deep interior processes, including the generation of the Earth's magnetic field. This magnetic field, a vital shield against harmful solar radiation, is intricately linked to the dynamics of the core, and any alterations in its behavior could have subtle, long-term effects. The researchers propose a cyclical model, suggesting that this pause or reversal in rotation is part of a multi-decadal oscillation, with similar phenomena potentially occurring in the early 1970s. Further research and continued monitoring of seismic activity are crucial to confirm this hypothesis and to gain a more comprehensive understanding of the complex interplay of forces shaping the heart of our planet. The findings underscore the dynamic nature of Earth's internal workings and highlight the ongoing quest to unravel the mysteries hidden deep within.

  • earth
  • Inner Core
  • geology
  • Geophysics
  • Science
  • Seismology
  • Earth's Rotation
  • Planetary Science
  • scientific research
  • Seismic Waves

  Summary of Comments ( 33 )
  https://news.ycombinator.com/item?id=43002130

  Verbose tl;dr

  HN commenters discuss the study's methodology and implications. Several express skepticism about the ability to accurately measure such deep Earth phenomena, questioning the certainty of the "paused" or reversed rotation claims. Some suggest alternative explanations for the observed data, like changes in the mantle's electromagnetic field influencing measurements. Others find the research fascinating, speculating about potential effects on Earth's magnetic field and the length of a day, albeit minor ones. A few highlight the limitations of current understanding of the Earth's interior and the need for further research. The overall tone is one of cautious interest mixed with scientific scrutiny.

  The Hacker News post titled "Earth's inner core may have changed shape, say scientists" linking to a BBC article, has generated a moderate number of comments discussing various aspects of the research and its implications.

  Several commenters focus on the speculative nature of the research and the limitations of our current understanding of Earth's interior. One commenter points out the difficulty in truly "knowing" what's happening at such depths, highlighting that the models used are inherently based on interpretations of indirect observations. This sentiment is echoed by another commenter who emphasizes the word "may" in the title, stressing the uncertainty inherent in these findings. Another adds to this by pointing out the ever-evolving nature of scientific understanding, citing previous theories about the inner core's rotation that have since been refined or superseded.

  Some comments delve into the technical details of the research, discussing the methodologies used and their potential limitations. One commenter questions the reliability of using seismic wave data to infer changes in the inner core's shape, suggesting that other factors could potentially influence the observed variations. Another discusses the concept of anisotropy and its role in affecting wave propagation, adding a layer of complexity to the interpretation of the data.

  A few comments offer more speculative interpretations of the research. One commenter wonders about the potential implications of these changes for the Earth's magnetic field, though acknowledging the lack of a clear link established in the research. Another ponders the possibility of other undiscovered layers or structures within the Earth's core, highlighting the vast unknown within our planet.

  A thread of conversation arises regarding the timescale of these changes, with one commenter asking about the rate at which the inner core might be changing shape. Another responds by highlighting the geological timescale involved, suggesting that these changes occur over very long periods.

  Finally, several commenters express general fascination with the research and the mysteries of Earth's interior. They appreciate learning about these complex processes and acknowledge the ongoing effort to understand our planet better.

  While no single comment stands out as overwhelmingly compelling, the collective discussion provides a nuanced perspective on the research, highlighting both its potential significance and the inherent limitations of our current understanding. The comments range from skepticism about the definitive nature of the findings to genuine curiosity about the implications for Earth's dynamics. The thread demonstrates the ongoing scientific process of questioning, interpreting, and refining our understanding of complex phenomena.