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Full Version: The superconductor dispute + The real reason we can’t outpace light speed
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Uh oh. Another nugget from that sinister lackey of mainstream or pop-sci physics disinformation, Don Lincoln. Wink
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Explanations for the cosmic speed limit often conflate mass with inertia.
https://bigthink.com/hard-science/light-...stic-mass/

KEY POINTS: Einstein's theory of relativity sets a cosmic speed limit: nothing can travel faster than the speed of light, posing challenges for space exploration. A widespread but incorrect explanation suggests that objects gain mass as they approach light speed, making further acceleration impossible. In reality, an object's mass remains constant, while its inertia changes with speed, ultimately preventing travel at or beyond the speed of light... (MORE - details)


A potential triumph in physics, dogged by accusation and doubt
https://undark.org/2023/03/27/a-potentia...and-doubt/

EXCERPTS: When University of Rochester physicist Ranga Dias announced this month that his lab had discovered a room-temperature superconductor — a feat that scientists have been chasing for decades — he drew excitement from some of his fellow physicists, but skepticism from others.

[...]  But the physics community has been here with Dias before. In 2020, a similarly bold claim from Dias — of a material that became superconducting at around 15 degrees Celsius (59 Fahrenheit) — unleashed a torrent of critiques and accusations of research misconduct, ultimately leading to the paper’s retraction last fall. Dias’ fiercest critics say that he has committed research misconduct, possibly on more than one occasion, and has yet to be held fully accountable. And they argue that his newest paper does little to address the serious technical questions that have been raised about his work. If anything, they suggest, it might raise new questions.

It “is like winning the lottery to discover a room-temperature superconductor, and they’re claiming to have done it multiple times,” said University of Florida physicist James Hamlin. “It just does not make sense.”

Jorge E. Hirsch, a professor of physics at the University of California, San Diego, who has been a staunch critic of Dias’ work, describes the controversy as having sown deep divisions in a burgeoning physics subfield. “There’s a lot of damage done because some people do believe it,” he said. “Students and postdocs and people don’t know what to believe.”

[...] In 2015, a team led by Mikhail Eremets, of Germany’s Max Planck Institute for Chemistry, showed that materials called hydrides could be superconducting at temperatures of -70 degrees Celsius when compressed in a diamond anvil cell, a molecular vice that squeezes tiny quantities of matter between two diamonds, crushing them to pressures around half that of the Earth’s core.

The discovery set off a rush to find other hydrides with even higher critical temperatures...

[...]  Dias has sent at least one of his critics, van der Marel, a series of cease-and-desist letters, demanding that van der Marel save all correspondence in case of legal action.

Some physicists say the controversy has cast a pall over the entire subfield of superconducting hydrides, seen by some as science’s best hope for achieving the sought-after goal of room-temperature superconductivity. “There’s a little renaissance going on, both in high-pressure experiments and the theoretical approach to materials discovery, superconductivity, superconductor discovery,” Hirschfeld said. “All those little renaissances are going on, but they’re both being held back or oppressed a little bit by the charges around ideas and skepticism in the community.” He added, “It’s definitely rubbed off on efforts to make and discover new materials.”

For Eremets, however, the heightened scrutiny of superconducting hydride experiments could prove to be a boon in the long run. Unlike Hirsch, he believes the evidence that hydrides can be superconducting remains incontrovertible, but he sees the controversy surrounding Dias’ work as a welcome reminder of the importance of independently verifying results... (MORE - missing details)