1. Alzheimer’s patients show impaired grammatical and syntactic processing, including difficulty with complex structures such as negation

A 2024 study on grammatical competence in Alzheimer’s disease found that AD patients show measurable deficits in sentence repetition, especially when the sentence contains syntactic complexity such as negation, embedding, or morphological markers.

This supports the idea that negation structures are harder for AD patients to process and reproduce accurately.

2. Speech‑based AD detection research shows that certain linguistic errors — including polarity and function‑word errors — are more common in AD speech

A 2024 arXiv study on speech‑recognition errors in AD detection notes that errors involving key functional words (like negation markers) have disproportionately high diagnostic importance.

This suggests that negation‑related mistakes are indeed characteristic of AD‑related language impairment.

What is a wave? In this series, I will be investigating the true nature, not just a bunch of equations, of electromagnetic waves.

A water wave requires a medium, namely water, to travel/propagate. Does electromagnetic waves require a medium of propagation? Long before people like Einstein claimed that electromagnetic waves EM could travel in “vacuum” (the space of complete emptiness) without any medium, most, if not all, physicists believed that EM waves, like water wave, required a propagation medium. They called it “ETHER” or “AETHER”.

The Ether as a Necessary Medium

Before the late 19th century, physicists treated the ether not as a speculative idea but as a necessary physical medium. Waves required a substance to oscillate in, and light was understood as a wave. The ether was therefore the invisible material that filled all of space, penetrated all matter, and carried electromagnetic disturbances.

But the consensus ended there. Different physicists imagined radically different ethers—elastic, fluid, granular, mechanical, or even quasi‑spiritual.

Newton, Huygens, and the First Divide

Isaac Newton never fully committed to a mechanical ether, but he speculated about a “subtle spirit” filling space, capable of transmitting forces. He imagined it as extremely rarefied, perhaps varying in density, and possibly responsible for gravity. Newton’s ether was not a mechanical lattice; it was a quasi‑material agent that could explain action at a distance.

Christiaan Huygens, by contrast, imagined a mechanical wave medium. For him, light was a pressure wave in an all‑pervading elastic substance. His ether had to be continuous, uniform, and capable of transmitting disturbances at enormous speed. It was the first clear attempt to treat the ether as a real physical continuum.

Faraday and the Field‑Ether

Michael Faraday believed the ether was not just a carrier of light but the substance of electric and magnetic fields themselves. He rejected the idea of charge as a material fluid and instead saw it as a state or tension of the ether. Lines of force were literal structures in this medium. Faraday’s ether was:

• continuous

• elastic

• capable of storing stress

• the seat of all electromagnetic phenomena

This was the conceptual seed that Maxwell later mathematized.

Maxwell’s Mechanical Ether

James Clerk Maxwell inherited Faraday’s intuition but tried to make it mechanical. In his early writings, he explicitly modeled the ether as:

• a mechanical medium filling all space

• supporting shear stresses like an elastic solid

• containing vortices whose rotations represented magnetic fields

• containing idle wheels or “molecular vortices” to transmit torque

Maxwell abandoned the literal gears and wheels later, but he never abandoned the ether. Even in his mature work, he insisted that electromagnetic energy must reside in a real physical medium, not in empty space.

Lord Kelvin and the Vortex Ether

William Thomson (Lord Kelvin) pushed the mechanical picture further. He imagined the ether as a perfect, continuous, incompressible fluid capable of sustaining vortex rings. These vortices were not just analogies—they were proposed as the actual structure of atoms. Kelvin’s ether was:

• frictionless

• continuous

• capable of supporting stable vortex knots

• the universal substrate of both matter and radiation

This was perhaps the most ambitious mechanical ether ever proposed.

Fresnel, Stokes, and the Fluid–Solid Paradox

Augustin‑Jean Fresnel argued that the ether must behave like a rigid solid to support transverse light waves. Yet it also had to allow planets to move through it without drag. His solution was a hybrid: the ether was rigid for optical phenomena but partially dragged by matter. This “partial ether drag” was an attempt to reconcile rigidity with astronomical observations.

George Stokes proposed the opposite: a viscous, fluid‑like ether that was completely dragged along by Earth. His ether flowed like a fluid but behaved elastically at high frequencies. This was another attempt to reconcile incompatible requirements.

Both models were ingenious, and both were unstable under deeper scrutiny.

Hendrik Lorentz and the Mathematical Ether

By the late 19th century, Hendrik Lorentz still believed in a stationary ether, but he stripped it of mechanical properties. For Lorentz, the ether was:

• motionless

• continuous

• the absolute reference frame for electromagnetic phenomena

• the seat of electric and magnetic fields

Matter interacted with the ether through charged particles, but the ether itself no longer had gears, vortices, or elasticity. It was becoming a pure field‑substrate, a conceptual remnant of earlier mechanical models.

Nikola Tesla and the Electrically Alive Ether

Nikola Tesla held one of the most unusual and uncompromising ether theories of the late 19th and early 20th centuries. Unlike Maxwell, Lorentz, or Kelvin, Tesla rejected the idea that empty space could contain abstract fields or that electromagnetic waves could propagate without a material substrate. For him, the ether was not a mechanical lattice or a mathematical convenience — it was a real, tangible, electrically responsive medium.

Tesla’s ether had several defining features:

• It was matter-like, composed of extremely small, highly mobile particles.

• It was incompressible, filling all of space uniformly.

• It interacted directly with electric charge, serving as the true substance behind electrostatic and electromagnetic phenomena.

• It enabled instantaneous electrical action, which Tesla believed was more fundamental than Maxwell’s wave picture.

Tesla rejected Maxwell’s interpretation of electromagnetic waves as self‑propagating fields. Instead, he insisted that what we call “radio waves” were disturbances in the ether, analogous to sound waves in air. He viewed the ether as a fluidic, dynamic medium that could be set into vibration, compression, or rarefaction by electrical apparatus.

In Tesla’s own words, the ether was “a fluid, filling all space,” whose properties made it the true carrier of both light and electricity. He believed that matter itself was a condensation or modification of this universal medium — a view that echoed, in a very different way, Kelvin’s vortex‑atom idea.

A Medium That Could Not Decide What It Was

Across these centuries, the ether was imagined as:

• a subtle spirit (Newton)

• an elastic wave medium (Huygens)

• a stressed field‑substance (Faraday)

• a mechanical lattice or vortex fluid (Maxwell, Kelvin)

• a rigid‑yet‑dragged solid (Fresnel)

• a viscous fluid (Stokes)

• a stationary mathematical backdrop (Lorentz)

The ether was indispensable, yet no one could agree on its nature. It had to be rigid but frictionless, solid but fluid, stationary but undetectable, universal but unobservable. The contradictions were already visible long before any interferometer was built.

Disclaimer: Since I am working on several other big projects, I have no choice but to use Copilot AI to help me write up my thoughts. Copilot is only my research assistant for data collection, math derivation, and literature review. All core ideas and mistakes are my own.