Skip to comments.Researchers look beyond space and time to cope with quantum theory
Posted on 10/28/2012 8:50:13 PM PDT by JerseyanExile
Physicists have proposed an experiment that could force us to make a choice between extremes to describe the behaviour of the Universe.
The proposal comes from an international team of researchers from Switzerland, Belgium, Spain and Singapore, and is published today in Nature Physics. It is based on what the researchers call a 'hidden influence inequality'. This exposes how quantum predictions challenge our best understanding about the nature of space and time, Einstein's theory of relativity. "We are interested in whether we can explain the funky phenomena we observe without sacrificing our sense of things happening smoothly in space and time," says Jean-Daniel Bancal, one of the researchers behind the new result, who carried out the research at the University of Geneva in Switzerland. He is now at the Centre for Quantum Technologies at the National University of Singapore.
Excitingly, there is a real prospect of performing this test. The implications of quantum theory have been troubling physicists since the theory was invented in the early 20th Century. The problem is that quantum theory predicts bizarre behaviour for particles such as two 'entangled' particles behaving as one even when far apart. This seems to violate our sense of cause and effect in space and time. Physicists call such behaviour 'nonlocal'. It was Einstein who first drew attention to the worrying implications of what he termed the "spooky action at a distance" predicted by quantum mechanics. Measure one in a pair of entangled atoms to have its magnetic 'spin' pointing up, for example, and quantum physics says the other can immediately be found pointing in the opposite direction, wherever it is and even when one could not predict beforehand which particle would do what. Common sense tells us that any such coordinated behaviour must result from one of two arrangements. First, it could be arranged in advance. The second option is that it could be synchronised by some signal sent between the particles.
In the 1960s, John Bell came up with the first test to see whether entangled particles followed common sense. Specifically, a test of a 'Bell inequality' checks whether two particles' behaviour could have been based on prior arrangements. If measurements violate the inequality, pairs of particles are doing what quantum theory says: acting without any 'local hidden variables' directing their fate. Starting in the 1980s, experiments have found violations of Bell inequalities time and time again. Quantum theory was the winner, it seemed. However, conventional tests of Bell inequalities can never completely kill hope of a common sense story involving signals that don't flout the principles of relativity. That's why the researchers set out to devise a new inequality that would probe the role of signals directly. Experiments have already shown that if you want to invoke signals to explain things, the signals would have to be travelling faster than light more than 10,000 times the speed of light, in fact. To those who know that Einstein's relativity sets the speed of light as a universal speed limit, the idea of signals travelling 10,000 times as fast as light already sets alarm bells ringing.
However, physicists have a getout: such signals might stay as 'hidden influences' useable for nothing, and thus not violating relativity. Only if the signals can be harnessed for faster-than-light communication do they openly contradict relativity. The new hidden influence inequality shows that the getout won't work when it comes to quantum predictions. To derive their inequality, which sets up a measurement of entanglement between four particles, the researchers considered what behaviours are possible for four particles that are connected by influences that stay hidden and that travel at some arbitrary finite speed.
Mathematically (and mind-bogglingly), these constraints define an 80-dimensional object. The testable hidden influence inequality is the boundary of the shadow this 80-dimensional shape casts in 44 dimensions. The researchers showed that quantum predictions can lie outside this boundary, which means they are going against one of the assumptions. Outside the boundary, either the influences can't stay hidden, or they must have infinite speed. Experimental groups can already entangle four particles, so a test is feasible in the near future (though the precision of experiments will need to improve to make the difference measurable). Such a test will boil down to measuring a single number. In a Universe following the standard relativistic laws we are used to, 7 is the limit. If nature behaves as quantum physics predicts, the result can go up to 7.3. So if the result is greater than 7 in other words, if the quantum nature of the world is confirmed what will it mean? Here, there are two choices. On the one hand, there is the option to defy relativity and 'unhide' the influences, which means accepting faster-than-light communication. Relativity is a successful theory that researchers would not call into question lightly, so for many physicists this is seen as the most extreme possibility.
The remaining option is to accept that influences must be infinitely fast or that there exists some process that has an equivalent effect when viewed in our spacetime. The current test couldn't distinguish. Either way, it would mean that the Universe is fundamentally nonlocal, in the sense that every bit of the Universe can be connected to any other bit anywhere, instantly. That such connections are possible defies our everyday intuition and represents another extreme solution, but arguably preferable to faster-than-light communication. "Our result gives weight to the idea that quantum correlations somehow arise from outside spacetime, in the sense that no story in space and time can describe them," says Nicolas Gisin, Professor at the University of Geneva, Switzerland, and member of the team.
You didn’t give an answer. How could you have? You never addressed the question. The question relates to the deviation of the earths orbit from a circle, as characterized by its eccentricity. You never got anywhere near this.
You provided a formula for the width of a 0.5mm pencil line forming an 8” circle scaled up to the size of earth’s orbit. You considered no information about the shape of this orbit.
“Trust me, I know what I’m doing.”
I was a physics TA! ... back in the day.
Physics TA... is a circle an ellipse?
Cooks know the answer to that question.
But the question is, granting that the earth’s orbit is an ellipse, how close is it to a circle? I’m saying that it is so close that it would, to scale, easily fit within an 8” diameter circle formed by an 0.5mm pencil line. OK?
The shallowness of your atheistic closed mind is stunning - almost numbing - in your inability to think outside the box. Transcendent is the concept you miss. If you reject it, reject away, but your arguments made no sense whatsoever.
I hope God doesn’t lose the password he put on to block others from hex-editing the universe. There would be consequences if, say, some curious chattering chimp got hold of the keys and started fiddling with the Planck Constant or some such. “Hmmm, let me just nudge this part up to 6.63, I’ll make this 10 to the negative 31st and see what happens.”
I find that quotes from the Hitchhiker's Guide to the Galaxy work pretty well anywhere as well.
Just wait until the boffins discover Bistromathematics, and improbability theory.
You could also say that C = mach 904,460 (32°F @ sea level)
To put it simply, show how temporal separation between events can occur without Time to prevent all events from occurring simultaneously. Use all the depths of your “outside box” thinking to provide an answer. Otherwise, you are claiming the equivalent of the existence of square-shaped triangles and when I ask you how, you say I’m not thinking deep enough.
Quantam physics have proven that time is a physical property, in other words, related to the property of space - and that is bends and changes. It is a dimension that is beyond the understanding of mere mortals - and yet mere mortals know there is a “there there” beyond our comprehension.
YOUR problem, my friend, is that you are coming at this from the template of man being the most superior being in the universe, which is atheistic by definition. You will never ever ever get it with that template. Man cannot even ask the proper questions about the limits of time and space, let alone answer them.
And yet you insist on man being the supreme. sorry, don’t fly....
Our atheist is still at it....
I asked you a very simple question: How is the temporal separation of events possible without Time?
The relevance of this question pertains to the claim that God is outside Time.
Just as God cannot be evil, since that would be an absurdity, the lack of temporal separation causes all events in a Timeless realm to collapse into a singularity moment (a logical consequence of the lack of Time). In such a realm, God did something and yet didn’t do it, simultaneously. This is the absurdity which arises from an entity ordering sequential events in a Timeless realm. How do you resolve it?
Which is why God is the Creator of time. In the beginning was nothing, a void, and since there was nothing to change there was no time. (Granted, even a single atomic [classic sense of indivisible] particle there would be no time because there is nothing relative to that particle wherewith to change.)
Any change requires Time to elapse, or else the change becomes an absurdity. If God conjured the moment to create Time, two phases exist, one where Time is yet to be created, and another where Time has already been created. Now both phases cannot exist simultaneously as that would bring about an absurdity, but the only thing that can prevent this simultaneity is Time itself, which is yet to be created during the change in the phases. This brings back the logical necessity of Time to allow any change.
While you are thinking about this, also consider the problem of Infinite Regress - for God to conjure a moment to do something, in a Timeless realm, what could the reference moment be to begin the conjured moment? If the past is infinitely endless, how can the present be arrived at?
You're thinking about this incorrectly. Like the person who says that distance of an arrow shot as a function of time d(t) such that each successive value of t the distance halves means that the arrow will never cover the entire distance. This is absurd [in life] because you can fire a bow and the arrow will cover that distance in some finite (and short) period of time.
You’re a hoot. Obtuse. Stubborn. A prisoner of your own templates while absurdly thinking you are above them - but a hoot nonetheless.
I’ll pray for you. I’m done chatting with you.
Yes, good old Zeno’s paradox. That was not what my question relates to, however.
Without a temporal past, how can any moment be begun?
’ Organized religion is going to have to learn to accept God’s universe(s) as they are. His wisdom, not ours, controls it’. This is so true for me except I believe there is only one ‘overall’ universe as there is only one God. I still enjoy pondering about the extent of his universe as to my take on time and space.