Posted on 08/17/2020 9:17:34 PM PDT by BenLurkin
Wigner sharpened the paradox by imagining a (human) friend of his shut in a lab, measuring a quantum system. He argued it was absurd to say his friend exists in a superposition of having seen and not seen a decay unless and until Wigner opens the lab door.
[Nora] Tischler and her colleagues have carried out a version of the Wigners friend test. By combining the classic thought experiment with another quantum head-scratcher called entanglementa phenomenon that links particles across vast distancesthey have also derived a new theorem, which they claim puts the strongest constraints yet on the fundamental nature of reality.
Until quantum physics came along in the 1920s, physicists expected their theories to be deterministic, generating predictions for the outcome of experiments with certainty. But quantum theory appears to be inherently probabilistic. The textbook version...says that until a systems properties are measured, they can encompass myriad values. This superposition only collapses into a single state when the system is observed...
Today most physicists concur that inanimate objects can knock quantum systems out of superposition through a process known as decoherence. Certainly, researchers attempting to manipulate complex quantum superpositions in the lab can find their hard work destroyed by speedy air particles colliding with their systems. So they carry out their tests at ultracold temperatures and try to isolate their apparatuses from vibrations.
Several competing quantum interpretations have sprung up over the decades that employ less mystical mechanisms...to explain how superpositions break down without invoking consciousness...The most exotic is the many worlds view, which says that whenever you make a quantum measurement, reality fractures, creating parallel universes to accommodate every possible outcome. Thus, Wigners friend would split into two copies and, with good enough supertechnology, he could indeed measure that person to be in superposition from outside the lab...
(Excerpt) Read more at scientificamerican.com ...
How the hell do you get cats to wear bib overalls?
CC
So this is how the Friends of Wigner began!
I feel that this is so important that it doesn’t matter at all.
Because they don’t like galluses or belts. Cats are eminently practical.
Lots of nip.
Ever learning, but never coming to the truth. Send more money for sure. Otherwise my superposition at the institute will collapse and I will have to wait tables to eat.
Like the shirt and the bearer thereof.
Yes, but will it pay the rent? There is something not quite scientific when physics and metaphysics are mingled.
A physicist knocked off his cat and now he’s going for his only friend?
Maschinenmensch is one of my favorite dancers. She knows how to superposition!
Biocentrism. Is a hot babe really a hot babe before somebody leers at her?
And why does beer have something to do with it?
The imaginary cat is EITHER alive OR dead. Alive and dead are mutually exclusive. A creature cannot be both at the same time. An observer may not know if the creature is alive or dead. That is not the same as the creature being both alive and dead at the same time.
Someday I’ll get around to watching that one.
“I think we have collapsed the superposition of this study - ITS GRANTS!!”
Yeppers.
Soon, grants will flow for Global Cooling studies, too, as we enter a Grand Solar Minimum.
How the hell do you get a cat to wear bib overalls?
It’s a Woodstock throwback. So many think calico is tiresome. It’s akin to Amish rebellion.
Scientific American actually publishing a hard science article!
Who knew?
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.