Welcome to this edition of Over a Cup of Coffee!

In this newsletter

• Generating energy from Earth’s rotation

• Dyson swarm would raise Earth’s temperature

• Why don’t we remember our childhood?

• Alzheimer's may not be a brain disease

Generating energy from Earth’s rotation

A team of physicists from Princeton University, NASA’s Jet Propulsion Laboratory and Spectral Sensor Solutions have proposed the idea of generating electricity by tapping into the Earth's rotational energy. The researchers have even performed tests to see if a device could produce electricity from the earth's rotation, through interaction with the earth's magnetic field. The paper faced criticism due to prior theories predicting voltage cancellation.

To test if voltage could be captured by preventing cancellation, researchers constructed a device with a manganese-zinc ferrite cylinder, acting as a magnetic shield. By angling the cylinder 57° north-south, they ensured it was perpendicular to the Earth's rotational motion and magnetic field. To measure voltage, electrodes were placed at the cylinder's ends, and to avoid photoelectric effects, the room was darkened. An unexplainable 18 microvolts were detected across the cylinder, leading them to conclude it was generated by the Earth's rotation.

The researchers took into consideration and ruled out temperature differences as a cause of the voltage. Furthermore, they observed no voltage when the cylinder's orientation was altered or when control cylinders were used. For conclusive proof and to exclude any potential sources of error, the experiment must be replicated by other researchers under a variety of conditions. However, the researchers suggest that if their findings are validated, the generated electricity could be scaled up to a practical level. 

The insights were published in the journal Physical Review Research.

Dyson swarm would raise Earth’s temperature

Planets within a Dyson swarm experience increased heat. A new paper calculates a 140K temperature rise for Earth from an outer swarm. A Dyson swarm is a theoretical megastructure, a collection of orbiting objects designed to capture a star's energy. Despite being rooted in science fiction, the idea of a Dyson swarm has motivated actual research, particularly concerning future energy demands for space exploration.

A civilization harnessing a star's energy, like with a Dyson swarm, would be a Type II on the Kardashev scale, a measure of technological energy use. Photovoltaic technology is key for Dyson swarm energy capture, but its efficiency hinges on temperature. Balancing heat from the sun and space across the large structure is a major challenge. The study explores the feasibility of building a Dyson swarm using local resources, while ensuring Earth remains habitable, a critical balance between energy needs and life support.

The study found a full Dyson sphere would impacts Earth's climate severely. Inner spheres are problematic, and outer spheres would cause a 140K temperature rise, making Earth uninhabitable. To balance energy needs and Earth's habitability, a partial Dyson swarm at 2.13 AU could harvest 15.6 yottawatts, causing a minimal 3K warming, though it demands an enormous amount of silicon.

The findings were published in the journal Solar Energy Materials and Solar Cells.

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Why don’t we remember our childhood?

We all struggle to remember infancy. Studies indicate these memories aren't lost, just inaccessible later in life. 26 infants, between 4.2 and 24.9 months old, were studied, with groups of under 12 months and 12-24 months. Infants in the study underwent fMRI scans while viewing images. Researchers monitored hippocampal activity which is linked to memory and emotion. 

After a delay, babies viewed familiar and new images side-by-side. Their eye movements were recorded. The researchers interpreted longer viewing of the familiar image as memory recall, and a lack of preference as an indication of less developed memory. The study found increased hippocampal activity in older infants during memory formation, and orbitofrontal cortex activity during recognition. This is likely due to significant changes in the body.

This urges parents to consider infancy's lasting impact, despite memory retrieval limitations. At this age, babies learn language and world patterns, evident when they respond to familiar songs or books. Though early memories are inaccessible, those experiences shape you, both neutrally and emotionally. 

The insights were published in the journal Science. 

Alzheimer's may not be a brain disease

Scientists have long targeted beta-amyloid clumps in the brain to treat Alzheimer's. After 30 years, researchers believe Alzheimer's is primarily an immune system disorder in the brain, not a brain disease. The immune system repairs and protects the body.

Brain trauma or bacteria trigger beta-amyloid's immune response. Due to molecular similarities, it mistakenly attacks brain cells. Immune system confusion leads to brain cell loss and dementia, suggesting Alzheimer's is an autoimmune disease. The model suggests beta-amyloid aids the immune system but also drives the autoimmune process in Alzheimer's. While typical autoimmune drugs may not work, targeting brain immune pathways could yield new Alzheimer's treatments.

Besides the autoimmune theory, other Alzheimer's theories are emerging, like the mitochondrial dysfunction hypothesis. Mitochondria turn oxygen and glucose into energy for cognitive functions. Other theories link Alzheimer's to brain infections from oral bacteria or abnormal metal processing. 

The insights were published in The Conversation.

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Thanks for reading.
Until next time,
Adya