How big is the quantum realm?

[DoomYoshi]

Bigger than you might think:
https://www.sciencenews.org/article/sap ... at-quantum

Scientists put a jiggling piece of sapphire crystal in what’s known as a “cat state,” in which an object exists in two different states simultaneously. It’s a situation reminiscent of physicists’ favorite imaginary feline, Schrödinger’s cat, known for being alive and dead at the same time.

The new sapphire cat is a relatively hefty 16 micrograms, physicists report in the April 21 Science. That’s close to half the mass of an eyelash, and more than 100 trillion times the mass of cat states previously created with molecules. “We’ve reached a new regime where quantum mechanics apparently does work,” says physicist Yiwen Chu of ETH Zurich.

[jimboston]

My head just exploded.

Seriously though… some of this stuff is pretty hard to ‘really’ process.

Lots of people will quote verbatim stuff like Schrödinger’s Cat… but I doubt how many who have heard of it truly grasp the concept.

[DoomYoshi]

I've read it a few times and I am flummoxed by the claim that it would be visible to the naked eye.

[bigtoughralf]

What are the potential applications of this? Will people be able to prank each other with black holes?

[jonesthecurl]

No but they can post cute pics of 'cat states' on social media.

[mookiemcgee]

[jimboston]

I've read it a few times and I am flummoxed by the claim that it would be visible to the naked eye.

half the mass of an eyelash? Depends how good your eyesight is.
I’m over 50 so not so great anymore.

Presumably only viewable 50% of the time?
Like what do they mean by “different quantum states”?
Would it appear to blink into and out-of existence?

Sounds like they are trying to reverse engineer some alien tech.

[bigtoughralf]

Schrödinger's cat confirmed kawaii

[jusplay4fun]

I've read it a few times and I am flummoxed by the claim that it would be visible to the naked eye.

half the mass of an eyelash? Depends how good your eyesight is.
I’m over 50 so not so great anymore.

Presumably only viewable 50% of the time?
Like what do they mean by “different quantum states”?
Would it appear to blink into and out-of existence?

In quantum physics, a quantum state is a mathematical entity that provides a probability distribution for the outcomes of each possible measurement on a system.

Sounds like they are trying to reverse engineer some alien tech.

For electrons, two different quantum states are represented by the spin of the electron in a magnetic field.

S.A. Goudsmit and G.E. Uhlenbeck, in 1925, recommended that an electron has an inherent angular momentum that is a magnetic moment that is recognised as spin. In atomic physics, the inherent angular momentum of a particular particle is parametrized by spin quantum numbers. The spin quantum number is the fourth number.

And the mass of an electron is about 9.1 x10^-28 grams, so the quantity in question, is to me, quite significant.

[jonesthecurl]

I had a very odd dream last night. I wasn't allowed to wake up until I completed the following limerick...

I felt a great sense of elation
When I solved the quadratic equation
Which involved a hyena
and a quantum John Cena.
It really was quite the occasion.

[saxitoxin]

Will people be able to prank each other with black holes?

EXCUSE ME ... it's called BIPOC vagina, racist

[jusplay4fun]

Despite studying Quantum Mechanics in at least 3 courses, I find most of it very perplexing.

Advances in this realm is interesting. To answer one of ralph's questions, one of the most interesting applications of this is Quantum Computing.

What is Quantum computing?
Quantum computing is a multidisciplinary field comprising aspects of computer science, physics, and mathematics that utilizes quantum mechanics to solve complex problems faster than on classical computers. The field of quantum computing includes hardware research and application development. Quantum computers are able to solve certain types of problems faster than classical computers by taking advantage of quantum mechanical effects, such as superposition and quantum interference. Some applications where quantum computers can provide such a speed boost include machine learning (ML), optimization, and simulation of physical systems. Eventual use cases could be portfolio optimization in finance or the simulation of chemical systems, solving problems that are currently impossible for even the most powerful supercomputers on the market.

[jusplay4fun]

Albert Einstein famously said that quantum mechanics should allow two objects to affect each other’s behaviour instantly across vast distances, something he dubbed “spooky action at a distance”. Decades after his death, experiments confirmed this. But, to this day, it remains unclear exactly how much coordination nature allows between distant objects. Now, five researchers say they have solved a theoretical problem that shows that the answer is, in principle, unknowable.

The Physics of Einstein (General Relativity) and Newton govern the behaviour of objects that most of us interact with (cars, balls, hammers, etc.) each day. The world of the microscopic (actually SMALLER that what can be seen with conventional microscopes) is governed or at least explained by quantum mechanics, the very very small, such as electrons (mass = 9.1 x 10^-31 g).

Many physicists, including Einstein and Stephen Hawking failed to combine the two parts in a meaningful way. That attempt is call the Theory of Everything, among other things.

Is string theory, superstring theory, or M-theory, or some other variant on this theme, a step on the road to a "theory of everything", or just a blind alley?

[riskllama]

on average, how many balls do you interact with on a daily basis, jp?

[Maxleod]

Albert Einstein famously said that quantum mechanics should allow two objects to affect each other’s behaviour instantly across vast distances, something he dubbed “spooky action at a distance”. Decades after his death, experiments confirmed this. But, to this day, it remains unclear exactly how much coordination nature allows between distant objects. Now, five researchers say they have solved a theoretical problem that shows that the answer is, in principle, unknowable.

The Physics of Einstein (General Relativity) and Newton govern the behaviour of objects that most of us interact with (cars, balls, hammers, etc.) each day. The world of the microscopic (actually SMALLER that what can be seen with conventional microscopes) is governed or at least explained by quantum mechanics, the very very small, such as electrons (mass = 9.1 x 10^-31 g).

Many physicists, including Einstein and Stephen Hawking failed to combine the two parts in a meaningful way. That attempt is call the Theory of Everything, among other things.

Is string theory, superstring theory, or M-theory, or some other variant on this theme, a step on the road to a "theory of everything", or just a blind alley?

Einstein also famously said "God doesn't play dice" (or something like that). I always thought that meant he completely discarded quantum physics (maybe because it doesn't work with his relativity theory? too proud?).

[DoomYoshi]

[jusplay4fun]

Albert Einstein famously said that quantum mechanics should allow two objects to affect each other’s behaviour instantly across vast distances, something he dubbed “spooky action at a distance”. Decades after his death, experiments confirmed this. But, to this day, it remains unclear exactly how much coordination nature allows between distant objects. Now, five researchers say they have solved a theoretical problem that shows that the answer is, in principle, unknowable.

The Physics of Einstein (General Relativity) and Newton govern the behaviour of objects that most of us interact with (cars, balls, hammers, etc.) each day. The world of the microscopic (actually SMALLER that what can be seen with conventional microscopes) is governed or at least explained by quantum mechanics, the very very small, such as electrons (mass = 9.1 x 10^-31 g).

Many physicists, including Einstein and Stephen Hawking failed to combine the two parts in a meaningful way. That attempt is call the Theory of Everything, among other things.

Is string theory, superstring theory, or M-theory, or some other variant on this theme, a step on the road to a "theory of everything", or just a blind alley?

Einstein also famously said "God doesn't play dice" (or something like that). I always thought that meant he completely discarded quantum physics (maybe because it doesn't work with his relativity theory? too proud?).

The "God does not play dice" quote was made during Einstein's debate(s) with Neils Bohr (of Denmark), one of the Founding Fathers of the Quantum Mechanics and the leader of the "Copenhagen Interpretation." Simply put, Quantum Mechanics was about odds (probability and statistics) and discusses Probability States for electrons. Einstein had a fundamental belief in Causality (A causes B) and disliked this interpretation of nature being based on Probability.

Causality is one of the most fundamental and essential notions of physics.[43] Causal efficacy cannot 'propagate' faster than light. Otherwise, reference coordinate systems could be constructed (using the Lorentz transform of special relativity) in which an observer would see an effect precede its cause (i.e. the postulate of causality would be violated).

Here is an interesting read on this subject:

https://arxiv.org/ftp/arxiv/papers/1301/1301.1656.pdf#:~:text=One%20of%20Albert%20Einstein's%20most,play%20dice%20with%20the%20universe%E2%80%9D.

and let me close with this:

How did Bohr reply to Einstein's famous phrase God does not play dice?
Einstein and Bohr. Einstein liked inventing phrases such as "God does not play dice," "The Lord is subtle but not malicious." On one occasion Bohr answered, "Einstein, stop telling God what to do."

[bigtoughralf]

Very accurate. This is why no one trusts scientists any more.

[jusplay4fun]

Very accurate. This is why no one trusts scientists any more.

Again, ralph show his ignorance.

We do know why there is static charge (electrons are rubbed off one object and create a charge unbalance) and about ice skating (the ice at the contact point with the blade melts and provides a groove for the blade and skater to move along). I do not know about the sand flow; I am sure someone can explain that.

[DoomYoshi]

Hmm... jp, when that comic was made there was no evidence for Michael Faraday's hypothesis. It was only proved to be possible in a computer simulation within the last year. I don't think that fully meets the parameters of what is considered proof in physics.
https://www.pnas.org/doi/10.1073/pnas.2209545119

Sliding on ice is a familiar experience, but we still do not fully understand why is ice slippery. Faraday hypothesized that ice forms spontaneously a thin quasi-liquid layer on its surface, while Reynolds suggested that this layer could act as a lubricant. However, experimentally probing the structure of ice below a slider is extremely challenging.

As for the triboelectric effect... it is still unknown. See this paper from last year:
https://www.researchgate.net/publicatio ... lectricity

Friction-driven static electrification is familiar and fundamental in daily life, industry, and technology, but its basics have long been unknown and have continually perplexed scientists from ancient Greece to the modern high-tech era. Despite its simple manifestation, triboelectric charging is believed to be very complex because of the unresolvable interfacial interaction between two rubbing materials

I'm sorry that I can't meet your exacting standards of Wikipedia quotes. Perhaps you will accept my sources.

[jusplay4fun]

There are many things we do not TRULY understand.

Think about it: what do we truly understand in Physics? Causality in the macroworld is one such, but getting down to the molecular level means quantum effects become more significant.

Proof can be tenuous on some things. What constitutes proof? I doubt we can address all such questions to the level demanded by positivism.

Are you aware of the Heisenberg Uncertainty Principle? There are implications from that.

[DoomYoshi]

I'd take as proof an experiment with a p-value of 0.003, which is pretty standard for physicists.

Or you could even just bring a link which proves your own stated claims above. You said "we do know why there is static charge". Could you back that up?

Uncertainty principle doesn't apply here. If it does, perhaps you can show that.

[jusplay4fun]

I'd take as proof an experiment with a p-value of 0.003, which is pretty standard for physicists.

Or you could even just bring a link which proves your own stated claims above. You said "we do know why there is static charge". Could you back that up?

Uncertainty principle doesn't apply here. If it does, perhaps you can show that.

The Uncertainty Principle applies here in the philosophical sense, not in terms of its strict application.

as far as static electricity:

Have you ever walked across the room to pet your dog, but got a shock instead? Perhaps you took your hat off on a dry winter’s day and had a “hair raising” experience! Or, maybe you have made a balloon stick on the wall after rubbing it against your clothes?

Why do these things happen? Is it magic? No, it’s not magic; it’s static electricity!

Before understanding static electricity, we first need to understand the basics of atoms and magnetism.

https://www.loc.gov/everyday-mysteries/physics/item/how-does-static-electricity-work/

and one more:

What are the Causes of Static Electricity in Manufacturing?
The main causes of static electricity are:

Contact and separation between two materials (including friction, travelling over rollers, etc)
Rapid heat change (e.g. material going through an oven)
High energy radiation, UV, X-ray, intense electric fields (not very common in industry)
Cutting action (e.g. a slitter or sheet cutter)
Induction (standing in the electric field generated by a static charge)

https://fraser-antistatic.com/knowledge-centre/faqs/causes-of-static-electricity-in-manufacturing/#:~:text=The%20main%20causes%20of%20static,not%20very%20common%20in%20industry)

Do those sites and references rise to your criteria of

p-value of 0.003,

??

[Maxleod]

Question:

c (the speed of light in vacuum) is a physical constant, and nothing can go faster.

Now let's say a spaceship travelling in space at a high speed turns its lights on (like a car on the road), wouldn't the speed of the light coming from the spaceship's lights be higher than c?

Please explain JP.

[mookiemcgee]

Question:

c (the speed of light in vacuum) is a physical constant, and nothing can go faster.

Now let's say a spaceship travelling in space at a high speed turns its lights on (like a car on the road), wouldn't the speed of the light coming from the spaceship's lights be higher than c?

Please explain JP.

No, the 'spaceships lights' would just move at the same speed as the ship is already moving.