Como a mecânica quântica pode ser ainda mais estranha

quinta-feira, junho 23, 2016

How Quantum Mechanics Could Be Even Weirder

And what it could mean for the future of computing


Why doesn’t the world make sense? At the fundamental level of atoms and subatomic particles, the familiar “classical” physics that accounts for how objects move around gives way to quantum physics, with new rules that defy intuition. Traditionally these are expressed as paradoxes: particles that can be in two places at once, cats that are simultaneously alive and dead, apparently impossible faster-than-light signaling between distant particles. But quantum rules are perfectly logical and consistent—the “paradoxes” are the result of our trying to impose on them the everyday reasoning of classical physics.

What’s more, over the past several decades we’ve come to understand that the classical and quantum worlds don’t exactly operate by “different” rules. Rather, the classical world emerges from the quantum in a comprehensible way: you might say that classical physics is simply what quantum physics looks like at the human scale.

All the same, we’re confronted with the question: why is the quantum world the way it is? Why do fundamental particles dictate this set of rules and not some other? Normally that question carries an implication that quantum particles are being a bit perverse by not behaving like billiard balls, reassuringly solid and definite and thing-like. But that might be the wrong way to think about it. Last December, I spoke with Romanian-British physicist Sandu Popescu of Bristol University in England, who told me that things could have been even stranger than quantum.

In fact, Sandu said, we’re not even completely sure that things aren’t even stranger. Maybe we just haven’t detected this extra strangeness yet.

Scribbling on his whiteboard with infectious enthusiasm, Sandu explained that this hypothetical “super-quantum” world comes into view by thinking about what now seems to be the defining characteristic of quantum theory: nonlocality.

Increasingly, it looks as though we have come at quantum mechanics from the wrong direction. At first it seemed to be about how energy is not continuous but is divided up into discrete chunks (quanta). Then it seemed to be about how quantum objects have to be described by smeared-out, wavelike mathematical entities called wave functions. Then, the question became how all the possible states of an object encapsulated by a wave function get crystallized into just one state when we measure it using classical apparatus. But in 1935, Einstein and two younger colleagues unwittingly stumbled upon what looks like the strangest quantum property of all, by showing that, according to quantum mechanics, two particles can be placed in a state in which making an observation on one of them immediately affects the state of the other—even if they’re allowed to travel light years apart before measuring one of them. Two such particles are said to be entangled, and this apparent instantaneous “action at a distance” is an example of quantum nonlocality.

Erwin Schrödinger, who invented the quantum wave function, discerned at once that what later became known as nonlocality is the central feature of quantum mechanics, the thing that makes it so different from classical physics. Yet it didn’t seem to make sense, which is why it vexed Einstein, who had shown conclusively in the theory of special relativity that no signal can travel faster than light. How, then, were entangled particles apparently able to do it?





All this fits with a growing conviction among many physicists that quantum mechanics is at root a theory not of tiny particles, but of information. It’s about how much we can deduce about the world by looking at it, and how that depends on intimate, invisible connections between here and there.

Qual é mesmo uma teoria científica que tem a INFORMAÇÃO no seu corpus teórico, e INFORMAÇÃO COMPLEXA ESPECIFICADA? Qual mesmo? Qual? A teoria do Design Inteligente!

Fui, nem sei por que, rindo, mas rindo de rachar da cara de alguns amigos cientistas da Nomenklatura científica e da Galera dos meninos e meninas de Darwin, pois a cada dia que a ciência avança em suas descobertas, mais a TDI é corroborada e fortalecida epistemologicamente. E a nova teoria geral da evolução - a SÍNTESE EVOLUTIVA AMPLIADA/ESTENDIDA, anunciada em agosto de 2015, é uma teoria científica natimorta, pois considerou a informação genética en passant...