Physicists introduce another quantum animal: The Quantum Pigeon

Aug 05, 2014
At the present moment another measurement is performed which is influenced both by what happened earlier and what happened later. Credit: Jeff Tollaksen

Recently physicists at Chapman University's Institute for Quantum Studies introduced the Quantum Cheshire Cat. Now they have introduced another quantum animal: the Quantum Pigeon.

In the 20th century, two revolutions in physics shook the world. One of them was relativity, discovered by Einstein. It revealed that spacetime is not what we experience in everyday life. For example, if you travel close to the speed of light, then you will age more slowly than somebody who stays on Earth.

The second revolution was , the microscopic theory of particles, such as electrons, atoms, or photons. Quantum theory showed that nature is not deterministic—as Einstein put it, "God plays with dice." After a century of careful testing, most physicists believe that the "chanciness" or "capriciousness" of the microscopic world is fundamental.

One of the most exotic aspects of nature is quantum non-locality which was first discovered more than four decades ago. It is referred to as "the most profound discovery of science."

There are different types of non-locality which quantum mechanics showed could not exist in classical physics. In for a particle to experience a force, it must be at the same location where the force is. In quantum mechanics you can have a force in one place while the particle moves outside. Nevertheless, the particle will still feel this force. This is called the Aharonov-Bohm effect.

There is another kind of non-locality that has to do with the relation between two particles that used to be next to each other in the past and then subsequently were separated to a large distance. Even after they were separated far apart, they appeared to maintain a strange kind of connection—what Einstein called "spooky action at a distance." However, these surprising kinds of connections had many limitations. For example, the particles had to originally be next to each other and only a relatively small number of particles in the universe could be connected with each other at a .

While the above was remarkable enough, now it appears this was only part of the story as demonstrated in a recent paper by a team from the Institute for Quantum Studies at Chapman University co-authored by Yakir Aharonov, Fabrizio Colombo, Sandu Popescu, Irene Sabadini, Daniele Struppa, and Jeff Tollaksen. They introduced a new kind of quantum connectivity between particles which transcends these limitations. This connectivity is happening all the time on a much bigger, cosmic scale.

"With the new kind of quantum linkages which we have introduced, the particles don't have to interact in the past. In fact, they have no idea that the other particle even existed," said Jeff Tollaksen, Director of the Institute for Quantum Studies at Chapman University.

"This is a surprising breakthrough," said physicist Paul Davies at Arizona State University in Tempe. "It's remarkable that it's still possible to discover something fundamentally new about quantum mechanics, which has been around for nearly 100 years. Here we see a richer, more complex set of long-range correlations that nobody knew existed before."

This breakthrough could only be seen by using another breakthrough also introduced by Aharonov concerning the nature of time. Our human experience of time is that it has a certain direction: we are born and then we grow older, not the other way around. But even with this experience, we are already making assumptions about the nature of time on a microscopic scale: the past that is not here, a present that is now here and the future that will be here later.

Aharonov turned Einstein's question around and asked, "Why does God play dice?" He found that Nature gains something very beautiful and exciting with this indeterminism: the present is not only affected by the past but it is also affected by the future. That is, the future (also known as post-selection) can come back to the present (like in the movie "Back to the Future"). So quantum mechanics does not pick out an arrow of time, it works just as well from past to future as from future to past. The quantum world links the future with the past in subtle and significant ways; and in dramatic contrast to everything previously known about time.

At first blush, you might think that we could build time machines with this new physics. If we could have such time machines, then when they take us back in time, a paradox will ensue: if one goes back in time in a time machine and kills one's grandfather, then that individual would never be born. If that individual will never be born how can they come back and kill their grandfather? This is the paradox that happens when we say that you are allowed to come back from the future and effect the past or the present.

In contrast, Aharonov (et. al.'s) theories don't allow for such paradoxes. It does this by using the explanation for why God plays dice: quantum mechanics has just the right kind of uncertainties so that when one does experiments in the present, there is always some possible noise in the result of this experiment, some possible mistakes due to the noise in the quantum uncertainties of the measuring device. Everybody knows that if your only tool is a hammer, then you tend to treat everything as if it were a nail. And the "hammer-type" measurements that are made in the present moment are not helpful in ascertaining the relevance of the future on the present. But a whole new world opens up when gentle measurements are made. For example, in some sense, particles everywhere are now more connected than previously thought.

"It seems to be impossible," says Tollaksen. "But it is a direct consequence of quantum mechanics" and, he adds, "It really has immense implications."

To backup such extraordinary claims, the Chapman University team has been introducing a series of new paradoxes which are consequences of this new kind of connectivity but which also can be verified experimentally. They have called the first the "quantum pigeonhole paradox." The classical pigeonhole principle states: "If you put three pigeons in two pigeonholes at least two of the pigeons end up in the same hole." This is an obvious yet fundamental principle of nature as it captures the very essence of counting. Yet the Chapman team showed that it was false in : "You can put an infinite number of pigeons in two boxes, and no two pigeons will be in the same box," says Tollaksen (see arxiv.org/abs/1407.3194).

"The new results seem fascinating," said Leonard Susskind of Stanford University. "I would guess that the new effect is a serious step in understanding quantum correlations."

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kochevnik
5 / 5 (3) Aug 05, 2014
The partitioning of the our minds defines the past. The past is no more certain or real than the future. Both are projections of our perception. This result forever debunks the notion of a single, static past that exists independent of consciousness. The obvious question to historians would be if the past existed, where exactly is it? It is in our minds and some ephemeral quantum entanglements, together which bind the universe like a tapestry. Unwind a single individual's tread and the entire tapestry unravels
arom
1 / 5 (5) Aug 05, 2014
In the 20th century, two revolutions in physics shook the world. One of them was relativity, discovered by Einstein. It revealed that spacetime is not what we experience in everyday life. For example, if you travel close to the speed of light, then you will age more slowly than somebody who stays on Earth.

This is the familiar interpretation of Einstein's relativity, but the only remain problem which seems have no explanation is that how the moving person get younger! Maybe this new interpretation could answer the problem …
http://www.vacuum...23〈=en
Whydening Gyre
5 / 5 (3) Aug 05, 2014
Quantum theory showed that nature is not deterministic—as Einstein put it, "God plays with dice."
Einstein said exactly the opposite.
Whydening Gyre
not rated yet Aug 05, 2014
... For example, if you travel close to the speed of light, then you will age more slowly than somebody who stays on Earth.

This is the familiar interpretation of Einstein's relativity, but the only remain problem which seems have no explanation is that how the moving person get younger!

They don't. Who told you they did?
Your assumption is that if they move FASTER than light, symmetry would logically dictate that time will reverse direction. And vacuum mechanics has nothing to do with it.
bluehigh
5 / 5 (4) Aug 05, 2014
Einstein dismissed Quantum mechanics and the inclusion of probability into scientific explanations of fundamental physics - God does *not* play dice with the universe. Could someone please explain how the facts got twisted to support this article? Is this a test? A joke? April 1 ?

Whydening Gyre
5 / 5 (2) Aug 05, 2014
Isn't this possibly saying that all electrons in the Universe are really an infinite number of states of the same electron? Would resolve the "entanglement" questions....
Quantum Magician
3 / 5 (2) Aug 05, 2014
Oh yes yes..

Quantum non-locality, Quantum non-determinism, Quantum Cheshire Cats, Quantum Pigeons, Quantum Bulls...

The only thing that's left introducing now is the Quantum Asylum, where all the Quantum Harry Potters can meet to tackle the pure essence and infinite reaches of Quantum Insanity.

Just imagine the possibilities..
..........

Can't figure something out? Declare it fundamentally irrational. /sarcasm off
Mimath224
not rated yet Aug 05, 2014
@Whydening Gyre could we say the same for other particles? the article uses 'god' such as in '...It does this by using the explanation for why God plays dice:...'. Do you think they are being serious here and are invoking an almighty or is it just 'plug' at Einstein?
Tachyon8491
not rated yet Aug 06, 2014
I propose the Quantum Gorilla - it depends on the focus of the observer which particular particle is beating its chest...
George_Rajna
Aug 06, 2014
This comment has been removed by a moderator.
antialias_physorg
not rated yet Aug 06, 2014
: quantum mechanics has just the right kind of uncertainties so that when one does experiments in the present, there is always some possible noise in the result of this experiment, some possible mistakes due to the noise in the quantum uncertainties of the measuring device.

The fundamental limitation seems to be that you can't increase the information at any one time (e.g. by bringing back information from the future to the past/now).
However this opens up all kinds of interesting 'squeezing' experiments between past and future where you trade of increased uncertainty in one area against more certainty in others (weak measurements).

Fascinating stuff.
thingumbobesquire
not rated yet Aug 06, 2014
The doctrine of random acausality is like modern art: a mental disorder.
Pexeso
not rated yet Aug 06, 2014
This article does rather poor service in explanation of what the "quantum pigeonhole" paradox actually is about (and the comments of posters are corresponding). I'd recommend to visit the NS article, which explains it much better IMO (you may consider this scheme in this extent).

The "quantum pigeonhole" paradox is nothing which couldn't be derived from solution of classical Schrodinger equation, in this extent is just a new denomination for already well known effect, which follows from well known Pauli exclusion principle: "no two fermions can coexist at the same place". Mr. Aharonov just explained it from perspective of well known nonlocality of so-called weak measurement: you need at least three consecutive measurements for to get the distribution of three particles at two places
betterexists
1 / 5 (1) Aug 09, 2014
All of this is way above me!
In 1951, the first video tape recorder captured live images from television cameras by converting the camera's electrical impulses and saving the information onto magnetic video tape. Video recorders were sold for $50,000 in 1956, and videotapes cost $300 per one-hour reel.
I am wondering whether it is possible to get Videoclips of 1000 years ago? Was it saved anywhere. This idea captivates me!
Is it possible at least in the next century to get such Videoclips of Earlier Millennia?
At least any theories on it? Anyone thought of that?
A koi fish (carp) named Hanako lived for 226 years and Tortoises too live longer than humans. Do their Brains have those Videos?
jimbo92107
5 / 5 (2) Aug 10, 2014
It's a pretty big booboo to get one of Einstein's most important quotes 180 degrees wrong.

"Einstein himself used variants of this quote at other times. For example, in a 1943 conversation with William Hermanns recorded in Hermanns' book Einstein and the Poet, Einstein said: "As I have said so many times, God doesn't play dice with the world.""

Source: http://en.wikiquo...Einstein
Whydening Gyre
not rated yet Aug 10, 2014
It's a pretty big booboo to get one of Einstein's most important quotes 180 degrees wrong.

"Einstein himself used variants of this quote at other times. For example, in a 1943 conversation with William Hermanns recorded in Hermanns' book Einstein and the Poet, Einstein said: "As I have said so many times, God doesn't play dice with the world.""

Source: http://en.wikiquo...Einstein

He is, however, flipping a lot of coins...
Bob Osaka
not rated yet Aug 12, 2014
I don't get it. The math doesn't work. Three pigeons, two holes all pigeons enter one hole or the other, no two pigeons will be in the same hole at the same time. Simple algebra will tell you that's not true. Then bafflingly an infinite number of pigeons is introduced and the holes, they become superpositions of wave functions but no not really, each pigeon hole actually has an energy Eigenstate in the shape of two Schrodinger's cats which have infinitely voracious appetites consuming one pigeon at a time ensuring no two pigeons will be in the same hole.
This is touted as a breakthrough. The only breakthrough that may or may not occur is the thin ice upon which they're dancing.
If Aharonov et al are attempting to show the uniqueness of every particle with mass this is the wrong way.