Quantum weirdness in 'chicken or egg' paradox

September 3, 2018, University of Queensland
Quantum weirdness in 'chicken or egg' paradox
Credit: University of Queensland

The "chicken or egg" paradox was first proposed by philosophers in Ancient Greece to describe the problem of determining cause-and-effect.  

Now, a team of physicists from The University of Queensland and the NÉEL Institute has shown that, as far as is concerned, the chicken and the egg can both come first. 

Dr Jacqui Romero from the ARC Centre of Excellence for Engineered Quantum Systems said that in quantum physics, cause-and-effect is not always as straightforward as one event causing another. 

 "The weirdness of quantum mechanics means that events can happen without a set order," she said.

"Take the example of your daily trip to work, where you travel partly by bus and partly by train.

"Normally, you would take the bus then the train, or the other way round.

"In our experiment, both of these events can happen first," Dr Romero said.

"This is called `indefinite causal order' and it isn't something that we can observe in our everyday life."

To observe this effect in the lab, the researchers used a setup called a photonic quantum switch. 

UQ's Dr Fabio Costa said that with this device the order of events—transformations on the shape of light—depends on polarisation. 

 "By measuring the polarisation of the photons at the output of the switch, we were able to show the order of transformations on the shape of light was not set."

"This is just a first proof of principle, but on a larger scale indefinite causal order can have real practical applications, like making computers more efficient or improving communication."

The research was published in Physical Reviews Letters by the American Physical Society.

Explore further: Can the causal order between events change in quantum mechanics?

More information: K. Goswami et al. Indefinite Causal Order in a Quantum Switch, Physical Review Letters (2018). DOI: 10.1103/PhysRevLett.121.090503

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betterexists
1 / 5 (6) Sep 03, 2018
It is ESSENTIAL for Scientists to come up ASAP with that INITIAL Diploid Cell (Zygote) from which, with tinkering, ALL Plants and Animals can be made; Too many Useless Industries have hitherto prevented more innovative minds to reach that Top Ph.D Levels in SciTech. First Remove all those stupid, logic defying industries which have hitherto held humanity in their hold. Some may call them belief, entertainment whatever. We cannot leave for Nature to come up with new species taking millions of years, which can be done in labs in decades in the future. The Tools for that are still Missing now and hence this appears as an exaggerated claim !
betterexists
1 / 5 (5) Sep 03, 2018
It is ESSENTIAL for Scientists to come up ASAP with that INITIAL Diploid Cell (Zygote) from which, with tinkering, ALL Plants and Animals can be made; The Tools for that are still Missing now and hence this appears as an exaggerated claim !

First 'Test-tube' Baby Lions Born !
https://kormorant...n-brits/
Ojorf
3.5 / 5 (8) Sep 03, 2018
It is ESSENTIAL for Scientists to come up ASAP with that INITIAL Diploid Cell (Zygote) from which, with tinkering, ALL Plants and Animals can be made


You said it brother!
The fate of the universe literally depends on this, let's hope they get it right before its too late. How long do we have?
stanhin1
5 / 5 (6) Sep 03, 2018
betterexists wrote in part: "have hitherto held humanity in their hold" We have an alliterationist in our midst. ;)
danR
not rated yet Sep 03, 2018
This shouldn't be surprising if quantum events can be regarded as non-local and atemporal. I've had a growing suspicion, increased by further evidence of Penrose et al's CCC, that the fractionation of the four fields/forces and the precipitation of matter did not include quantum parameters, being altogether primordial. None of this is formally falsifiable at present, of course.

But in the conformal junction of universe-aeons, and throughout them, one of the few constants to survive immensurable dimensions of 'space' and 'time' would be the immutable properties of the quantum world.
IwinUlose
not rated yet Sep 03, 2018
"The weirdness of quantum mechanics means that events can happen without a set order," she said.


No insinuations intended: this sounds like a race condition.
HannaB
not rated yet Sep 03, 2018
In quantum mechanics chicken can come before egg, so that chicken and egg can come at the same moment w/out problem for both.
Hyperfuzzy
1 / 5 (3) Sep 03, 2018
My Logic professor insists potentiality before actuality; anything else is nonsense!
betterexists
1 / 5 (1) Sep 03, 2018
It is ESSENTIAL for Scientists to come up ASAP with that INITIAL Diploid Cell (Zygote) from which, with tinkering, ALL Plants and Animals can be made; The Tools for that are still Missing now and hence this appears as an exaggerated claim !

First 'Test-tube' Baby Lions Born !
https://kormorant...n-brits/

http://www.dailym...ubs.html
cgsperling
5 / 5 (1) Sep 03, 2018
@Hyperfuzzy said: "My Logic professor insists potentiality before actuality; anything else is nonsense!"

Sure, in the macro world. A the quantum scale, there is lots of nonsense.
Hyperfuzzy
1 / 5 (1) Sep 03, 2018
@Hyperfuzzy said: "My Logic professor insists potentiality before actuality; anything else is nonsense!"

Sure, in the macro world. A the quantum scale, there is lots of nonsense.

if u say so. don't build me a clock
Surveillance_Egg_Unit
3 / 5 (4) Sep 03, 2018
In quantum mechanics https://www.scien...eriment, so that chicken and egg can come at the same moment w/out problem for both.

says HannaB

In the Quantum Universe, as well as in the SubSet Universe (which is just below the Quantum level), the Realities of which we are most familiar with in our Macro existence do not normally exist at Quantum. The Laws at Quantum level are so extreme and different from what we see here in our own Reality that, if not for our wonderful science instruments that capture and record the effects and the events going on at Quantum, humans would be still lost and wondering as to "who came first".

But it is not Time itself that has reversed at Quantum, and the chicken/egg conundrum is simply a variation on the Schrödinger's Cat thought experiment.
There are far greater things at the Quantum level to peruse and quantify, rather than expressing Time as the culprit and blamed for slow or fast events
Surveillance_Egg_Unit
3.7 / 5 (3) Sep 03, 2018
-CONTINUED-
Time cannot reverse or be stilled. Only the duration of events can hold steady (such as if it were possible to approach the Event Horizon of a Black Hole); or speed up/slow down. eg-The parade passes by ever so slowly when a car's driver is intent on it going faster. It also depends on the mental perception of the viewer, as well as the mental state of that viewer.
The old American adage that "A watched pot never boils" is true. Things/events may seem to take "forever" even though Time itself is carrying on as usual.
There is also "Cosmic Time" that is measured in Light Years (LY) and there is Time that is measured with clocks that are geared toward measuring the duration of sunset - sunrise on various planets with different lengths of rotation.

The real question should be wrt to the first uni-cell before/after it divided into two cells in the waters of Earth - which came first?
Eikka
5 / 5 (3) Sep 03, 2018
The "chicken or egg" paradox was first proposed by philosophers in Ancient Greece to describe the problem of determining cause-and-effect.


And it was solved by philosophers in acient India, by proposing the concept of dependent origination (mutual co-arising), which is kinda like a pre-proto-version of QM.

They applied it mainly to the question of psychology, but the concept expands to physics as well.

"When this is, that is; This arising, that arises; When this is not, that is not; This ceasing, that ceases."

It sounds trivial, but it's basically saying that existence itself creates distinction. When nothing is, something is, when something is, it "splits" into distinctions or one and another etc. It's not causality where one thing -follows- from another, but more a matter of observation. The observer makes the difference, which is effectively saying that "Chicken and eggs are the same, until you ask which came first."

Sounds like QM superposition.
Hyperfuzzy
1 / 5 (1) Sep 03, 2018
My Logic professor insists potentiality before actuality; anything else is nonsense!

Or curious; funny how the lack of Logic gained popularity. Was it at the Death of Hypatia or Akhenaten?
Steelwolf
5 / 5 (4) Sep 03, 2018
The the whole Chicken/Egg question was popularized back then, it has been shown with archaeology that there were egg forming creatures before there were chicken like creatures, as in fish, and even eggs from creatures well before there was anything resembling the chicken. So, in THAT light the egg came first, and later, thru Lots of eggs, we ended up with Chickens, from which we get our nutritious, delicious eggs.

Is it wrong to use an egg batter on your crispy baked/fried chicken by Religious Laws?
Surveillance_Egg_Unit
4 / 5 (4) Sep 04, 2018
The the whole Chicken/Egg question was popularized back then, it has been shown with archaeology that there were egg forming creatures before there were chicken like creatures, as in fish, and even eggs from creatures well before there was anything resembling the chicken. So, in THAT light the egg came first, and later, thru Lots of eggs, we ended up with Chickens, from which we get our nutritious, delicious eggs.

Is it wrong to use an egg batter on your crispy baked/fried chicken by Religious Laws?

says Steelwolf

I gave you a 5 because egg batter on fried chicken sounds yummy.
:)
Religions are all man-made, but some of them do have certain laws that appear to have been good advice - such as the kosher law that advises against eating shellfish (especially in summer) but the USDA here in the States are aware of what is safe to eat and what isn't.
betterexists
1 / 5 (1) Sep 04, 2018
More importantly, How does the hen know that it has to sit over the eggs until they hatch. Also, How so many birds get the urge to build a nest beforehand, then bring in live fish to feed their just hatched babies. Which lives are more important ? No experiments in Neurology over these ? Why not interrupt functions of various brain cells to see their effect ?
PowerMax
5 / 5 (2) Sep 04, 2018
every time I read a comment from hyperfuzzy I immediately feel the urge to put my fingers in my eyes, push as hard as I can until I reach the brain and then start swirling fingers around. EVERY time. I don't know if he/she is trolling or not, but at this point, please, I ask you, dear hyperfuzzy, STOP COMMENTING!
betterexists
1 / 5 (1) Sep 04, 2018
It is ESSENTIAL for Scientists to come up ASAP with that INITIAL Diploid Cell (Zygote) from which, with tinkering, ALL Plants and Animals can be made; The Tools for that are still Missing now and hence this appears as an exaggerated claim !

https://phys.org/...rop.html
Hyperfuzzy
1 / 5 (1) Sep 04, 2018
every time I read a comment from hyperfuzzy I immediately feel the urge to put my fingers in my eyes, push as hard as I can until I reach the brain and then start swirling fingers around. EVERY time. I don't know if he/she is trolling or not, but at this point, please, I ask you, dear hyperfuzzy, STOP COMMENTING!

Logic cause you to get the willies? The lack 'causes me WTF!
Steelwolf
5 / 5 (1) Sep 04, 2018
I just wondered if there was some dietary restriction similar to the Kosher whereby they do not mix dairy and meat products and use different implements set aside for each. As I recall that comes from the 'do not boil the kid in the mother's milk', so I just wondered if it was ok to use egg batter with chicken or to scramble eggs with roasted chicken and onions on top of a bed of fried potatoes?

And in That case, the chicken comes WITH the egg...
Pt_ of Interest
not rated yet Sep 06, 2018
It seems to me that the breakthrough experiment by Aspect et al already was sufficient demonstration by the early 1980s--better actually.

What is described here, while possibly an important step in the march towards practical quantum computing, is really just a selection from two possible realities. So-to-speak, I have the egg-first universe and the chicken-first universe in linear superposition, and then we choose one. At no instant did these universes interact (i.e., display nonlinearity regarding each other). Whether choosing to accept (asymmetry-hypothesis) single actual universe model of Roger-Penrose from multiple potential histories, or the (symmetry-hypothesis) ever-dividing multi-universe of all possibilities proposed by Hugh Everett and held by the majority of the physics community, nonetheless, Roger Penrose provides the only practical point of departure of the linear superposition.
Pt_ of Interest
not rated yet Sep 06, 2018
This being "orchestrated reduction" of the wavefunction by a spread of the implied realities across a space on order of about 22 micrograms--one Planck mass, that is, a difference at a level that generates a single graviton--one quantum of curved spacetime. That is the wavefunction ship hits the "rock" of nonlinearity, or rather, the always separated realities (in linear superposition) flying under the nonlinearity radar screen reached that detection floor of a (the) universe.

On the other hand, the Aspect et al experiments or subsequent ones involving space and/or time separate of detecting systems of entangled particles demonstrated a reference-frame dependent causal chain. That is, in the limit of a perfectly symmetric measurement apparatus in space--if one's motion reference frame was such that the laboratory reference frame was in relative motion one way, then detector A was the cause of the collapse of particle A and B, other way, then B. Hence chicken&egg in 1 world.

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