Quantum Foam

[Tages]

This phrase has been used several times recently on this forum. I am ignorant of what this means.

The Wikipedia entry does not help me much.

Who wants to educate me?

[Valmore]

I have no clue. Perhapns it's one of those night clubs that employ foam and has a "Quantum Leap" theme or something.

[moebius]

My understanding is:

Space only looks uniform because we aren't able to magnify enough. If we could observe at Planck length, we would see that actually space looks like "foam," a medium perforated by all sorts of bubbles or irregularities. Within these perforations or irregularities, the laws of Einsteinian physics do not apply, allowing for things like wormholes.

I think there's an explanation of it somewhere in Crichton's "Timeline," which uses Quantum Foam to justify time travel. Bad book, but the science might be laymanesque.

[Agent Helix]

You know how when you get a delivery, and you open the box, and then suddenly the packing peanuts seem to exist at all places at all points in time?

That's quantum foam.

[Iangould]

I was in the middle of a lengthy and very erudite explanation when I hit the wrong combo of keys and closed the browser.

The short version - quantum mechanics says you can never measure both the mass and the energy of a particle with absolute certainty. All you can do is say that there's a given probability that either property lies within a certain range and the higher probability you attach to the measure of one of the characteristics, the more uncertain the other becomes.

One way in which this uncertainty can be explained is by the existence of "virtual particles". Virtual particles are actually pairs of particle - one matter and one anti-matter - which appear for vanishingly brief period of time and then annihilate each other. During the nanoseconds they exist, they interact with the particle you're trying to observe altering its mass or energy.

So even "empty" space is full of these ultra-short-lived and weakly interacting virtual particles which make up the so-called quantum foam.

[Dreadstar]

Ok, do you understand the idea behind Schrodinger's cat? That until you actually make the observation, the cat is neither alive nor dead or both? The Heisenberg Uncertainty Principle?

The idea is that there is no such thing as "empty" space. That way down below the Plank constant, something exists. But since, like Schrodinger's Cat, it's unobservable, it exists simultaneously in all states at once (or any of a myraid possible states). And this uncertain quantum state has a miniscule effect on the particles residing within it. aka the "observable" universe.

How about this? Everyone's heard the old philosphic idea that way down below the smallest particales, other universe might exist. That within an atom in your fingernail a universe might exist. And our universe might exist within the atom of some greater "reality". The nature or description of that universe from the perspective of the greater would be quantum foam. In fact, this particular philosophic argument gained a helluva lot of lip service back in the early 60's BECAUSE of the newly coined quantum foam theory.

[Shellhead]

Ok, do you understand the idea behind Schrodinger's cat? That until you actually make the observation, the cat is neither alive nor dead or both? The Heisenberg Uncertainty Principle?

The idea is that there is no such thing as "empty" space. That way down below the Plank constant, something exists. But since, like Schrodinger's Cat, it's unobservable, it exists simultaneously in all states at once (or any of a myraid possible states). And this uncertain quantum state has a miniscule effect on the particles residing within it. aka the "observable" universe.


I have all kinds of problems with the Shrodinger's Cat thought experiment. But today, I choose to focus on one pertinent point. The cat is sentient. If the cat is still alive, it is aware of that fact. It is useless to pretend otherwise, let alone extrapolate some fictitious undead state of being based purely on the researcher's ignorance.

[Dreadstar]

It's the idea that's important, not the cat.

[JeffreyWKramer]

It's the idea that's important, not the cat.

Beat me to it.

Shell, you're a pretty bright guy, but this time around, you are seriously missing the forest for the trees.

[Shellhead]

Beat me to it.

Shell, you're a pretty bright guy, but this time around, you are seriously missing the forest for the trees.

I just think that it's a terrible analogy and should be replaced with a more useful one. Quantum particles may indeed be in flux, but the cat is either or alive, and the ignorance of the researcher is irrelevant to that state of being dead or alive.

There was a philosopher in ancient Greece, Zeno of Elea, who declared that nobody could ever go anywhere, because before you could arrive anywhere, you first had to pass the halfway point. And then you had to pass the halfway point between the new halfway point and your destination. And so forth, leaving the traveller stranded between an infinite series of halfway points.

Of course, any sensible person realizes that is bullcrap, because people reach destinations all the time. The problem with Zeno's Paradox is that movement does not correspond with his arbitrary sequence of fractions. If I have a three foot stride and I am six feet from my destination, I will arrive there in the time that it takes me to make two steps, with that second step completely sailing past all of Zeno's fussy little halfway points.

Personally, I find Schrodinger's Cat to be the modern equivalent of Zeno's Paradox. The idea that he is really trying to convey might be more compelling to me if he used a better model to sell it. I'm not worried about the death of a hypothetical cat, but I find mere ignorance to be a poor basis for all the ideas stacked on top of Schrodinger's Cat, especially alternate realities.

[Dreadstar]

...The idea that he is really trying to convey might be more compelling to me if he used a better model to sell it. I'm not worried about the death of a hypothetical cat, but I find mere ignorance to be a poor basis for all the ideas stacked on top of Schrodinger's Cat, especially alternate realities.

Once more, with feeling:

It's merely an illustrative "model". *IF* you understand the concept, the model is unnecessary.

Get past it, forget the damned cat and move on.

[macul]

You know how when you get a delivery, and you open the box, and then suddenly the packing peanuts seem to exist at all places at all points in time?

That's quantum foam.

I thought it was the material inside bean bag chairs??

[niall mc cann]

Once more, with feeling:

It's merely an illustrative "model". *IF* you understand the concept, the model is unnecessary.

Get past it, forget the damned cat and move on.

NO!!!!!!

DEAR GOD! YOU MIGHT KILL THAT POOR CAT!?!

WTF kinda guy was this schroedinger?

Maniac!!!!!

[Calybos]

It's the idea that's important, not the cat.

Exactly. As an animal lover, I usually substitute "Schrodinger's amoeba," but it doesn't have the same zing.

[Josh S]

I have no clue. Perhapns it's one of those night clubs that employ foam and has a "Quantum Leap" theme or something.


That'd be the best night club ever.

[Lex]

I think there's an explanation of it somewhere in Crichton's "Timeline," which uses Quantum Foam to justify time travel. Bad book, but the science might be laymanesque.
Pfft. That's one of my favorite books.

[moebius]

Pfft. That's one of my favorite books.

Sorry, dude. There were some interesting ideas in there, but I just couldn't get into it. However, I remember they talk about Quantum Foam.

OT: Hope Senator Johnson is doing better. I hear he's out of the hospital.

[Paul McEnery]

Once more, with feeling:

It's merely an illustrative "model". *IF* you understand the concept, the model is unnecessary.

Get past it, forget the damned cat and move on.

But, but...

What if it was a really stupid cat?

:evilsmile

[Dreadstar]

Great, now I got Sammy Davis in my head saying "Man, that cat is stupid..."

[Sanagi]

Once more, with feeling:

It's merely an illustrative "model". *IF* you understand the concept, the model is unnecessary.

Get past it, forget the damned cat and move on.
To quote another somewhat startling metaphor, if you meet the Buddha on the road, kill him.

[Iangould]

NO!!!!!!

DEAR GOD! YOU MIGHT KILL THAT POOR CAT!?!

WTF kinda guy was this schroedinger?

Maniac!!!!!

"Dr. Schroedinger, there's someone from the Humane Society here to see you."

[PatrickG]

I think one important realization is that until the scientist sees the cat, the cat is not ONLY alive or dead. The cat could have also grown wings or a second head or become a dog. And no matter how small the chances of these things are, they're not UNTRUE until the cat is observed.

Also, the universe neither exists not doesn't exist, nor any of the permutations thereof, until the cat observes it. They're all simultaneously true.

I think the operative ideas here are:

- Quantum states/parallel realities

- That this experiment requires a box which has NO contact with the outside universe. You can't X-Ray it. No particles or radiation emits from it. The contents must be LITERALLY and ABSOLUTELY unknowable to the outside world and the outside world must be LITERALLY and ABSOLUTELY unknowable to the cat. No sound. No light. No subatomic particles or chemical reactions. Furthermore, it must be literally unknowable not only by present standards of detection but also by all future standards including those we've not yet become aware of if they exist.

The whole things is a bit like dividing by zero.

And a main point, as I understand it, is that something that is literally unknowable (for NO lack of trying) can be both true and false at the same time.

To coin a theological expression of Schrodinger's Cat:

If God is ambivalent or neglects a few details in His creation, then there is no dishonesty in stating the inevitability that Truth can contain mutually excluse premises simultaneously. And to accept contradictions no longer becomes a matter of hypocrisy or blasphemy but a form of wise and holy and reverent worship, an acknowledgement that God does not play by our rules; when God plays dice with the universe, there is no up or down of note and so all six sides of the dice count at once.