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I remember Wilczek said you have to let one thing "float":

According to the original uncertainty principle, to pin down a position accurately we must live with a large uncertainty in momentum. An addendum to Heisenberg’s original uncertainty principle is required by the theory of relativity, which relates space to time and momentum to energy. This additional principle says that to pin down a time accurately we must live with a large uncertainty in energy. Combining the two principles, we discover that to take high-resolution, short-time snapshots, we must let momentum and energy float.

Ironically, the central technique of the Friedman-Kendall- Taylor experiments, as we mentioned, was precisely to concentrate on measuring the energy and momentum. But there’s no contradiction. On the contrary, their technique is a wonderful example of Heisenberg’s uncertainty principle cleverly harnessed to give certainty. The point is that to get a sharply resolved space-time image you can—and must—combine results from many collisions with different amounts of energy and momentum going into the proton. Then, in effect, image processing runs the uncertainty principle backwards. You orchestrate a carefully designed sampling of results at different energies and momenta to extract accurate positions and times.
 

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How is that a "way around the uncertainty principle"? Here's the original article: http://arxiv.org/pdf/1206.2618v3.pdf

What they did was they built up the statistical picture of the system by continuously fitting their results to the Dirac probability distribution to a beam of particles they measure many times. Whereas HUP is talking about a single state. And before you say you can apply what they found for continuous stream of photons to just one, please see this: No-cloning theorem - Wikipedia, the free encyclopedia

They have a good idea of one part of the system while having a bad idea of the other part, falling within the limits of HUP. They characterized their system with probabilities which is what QM has been doing all along. Nowhere do I see them "circumventing" the uncertainty principle or anything like that.

Classic example of headline blowing things out of proportion, as is typical with QM research being hyped. And Heisenberg is still as relevant now as it was in the 1930's.
From your link:

Weakmeasurementsoccurintheoppositeregime,wherethecouplingis muchlessthanthepointerwidthδw.Inthiscase,theeigenstatesofˆAare notresolvedbythepointer,sothewavefunctiondoesnotcollapse.Therefore, asubsequentmeasurementperformedonthequantumstatecanbeusedto extractfurtherinformation.Ifthesubsequentmeasurementisstrong,suchthat theeigenstatesareresolved,wecanchoosetoconsideronlythestatisticsof oneparticularoutcome;thisiscalledpost-selectionandthechosenoutcomeof interestisthepost-selectedstate.
 

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@<span class="highlight"><i><a href="http://personalitycafe.com/member.php?u=16518" target="_blank">FreeBeer</a></i></span>

I. Entanglement

.....1. How does measuring the polarization of something create entanglement?
.....2. How does one break entanglement?

II. Time/Polarization of Entangled Particles
So effectively the polarization of the 1st and 2nd photon entangled produces a measure of time?

III. Experiments / Future Trends

.....1. The first experiment seems to be based around the idea of using entangled particles to create a "small universe" with the "clock" either independent or dependent on this to measure the passage of time

.....2. Looking at what I read, it would appear they wish to create a larger scale experiment, what I'm interested about is what it entails? I'm curious if they're planning on making some kind of gigantic universe simulation? That strikes me as potentially ethically problematic if you end up with a sufficiently complicated system (if you've ever seen the game "Life", even relatively small rules can produce rather complicated results that mimic organic systems...)
The universe we live in is already this such a simulation, no need to create one, just figure out a way to test it clearly.

IV. Other Questions/Notes
I'm curious as to this experiment yielding a result similar to a holographic universe theory, whereby basically a 3D image is the result of one or more 2D images. In this case, the polarization of several entangled particles ends up producing the phenomenon of time.
I don't know. I'm not a physicist.
 

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From your link:

Weakmeasurementsoccurintheoppositeregime,wherethecouplingis muchlessthanthepointerwidthδw.Inthiscase,theeigenstatesofˆAare notresolvedbythepointer,sothewavefunctiondoesnotcollapse.Therefore, asubsequentmeasurementperformedonthequantumstatecanbeusedto extractfurtherinformation.Ifthesubsequentmeasurementisstrong,suchthat theeigenstatesareresolved,wecanchoosetoconsideronlythestatisticsof oneparticularoutcome;thisiscalledpost-selectionandthechosenoutcomeof interestisthepost-selectedstate.
And? Again, this is based on a continuous measurement of a beam of photons rather than the state of one particular photon. The uncertainty principle still stands. If you don't understand why, please look into the uncertainty principle more as well as read the paper closely.
 

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I agree with quantum computing. I know fuck all about it, but it's such a hotly discussed subject that it is surely on its way. The pinnacle will be when computers reach their maximum physically possible speed. This will presumably be done only with quantum mechanics.
As far as I understand, they're relatively quite slow, but they can process ridiculous amounts of information at a time. Theoretically.

Which really doesn't make much sense to me, tbh, considering speed is how much information can be processed in a given amount of time. Just what I was told, maybe someone else knows what he was talking about.
 

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o_O why not? I don't get your obsession with authority on the subject, the fact that the past and the future are mental constructs we use to measure change is self evident. You can not really believe that time as we know it is a physical thing that exists outside of consciousness. The observer is a requirement.
Again, not necessarily true depending on your interpretation of quantum mechanics. Most physicists will disagree with the statement that consciousness is a necessary component (in the QM conference poll I cited, only 6% of 33 experts held that view). The observer doesn't exist outside of reality as something supernatural--it's not the act of conscious measurement, but the act of interfering with quantum systems that causes the wave function collapse.

o.o well similarly I can argue that ethics does not exist outside of the conscious observer(s). What we deem as right and wrong has no value outside of us. So in essence without us ethics does not exist, indeed ethics does not exist out there as a physical thing. It is emergent from consciousness. A rock is a emergent physical thing, ideas are not physical or palpable, neither is consciousness.
Ethics isn't related to science in the slightest because it's not quantifiable. Time, however, is. This is philosophical fantasy.

o.o I only believe what makes sense to me, but that doesn't mean its not true even if I don't believe it. I can think the world is flat, while it actually isn't. Absolute objective reality exists outside of myself, I am aware of this.

You can disagree with me and hold a completely different opinion at any time & Robyn can consider both sides. I may be wrong, but this is what I think is actually true in light of the problems between classical physics and quantum theory.
And you shouldn't because it is wrong, and you shouldn't be spreading false beliefs to people uneducated in theoretical physics.

You'd say time exists because we can measure it (because that is the definition), but that is still within the human context of how we try to make sense of what we see. The universe may actually not work like that at all. We require the concept of time, because all of known macroscopic physics would break down without it.
There's no scientific basis for that claim--it's pure philosophical silliness. Until a). you get your M.D. in quantum physics, or b). a model quantum gravity without space-time is successfully published and accepted, stop making unsupported assertions.

As for Barbour, don't believe everything you read.
EDIT: My mistake, The Secret isn't by Barbour. I was confusing it with The End Of Time. But you should still read that link.
 

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There's no scientific basis for that claim--it's pure philosophical silliness. Until a). you get your M.D. in quantum physics, or b). a model quantum gravity without space-time is successfully published and accepted, stop making unsupported assertions.
M.D. in quantum mechanics? Is that like for a doctor who specializes in the psychiatry of physicists? :tongue:
 

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And? Again, this is based on a continuous measurement of a beam of photons rather than the state of one particular photon. The uncertainty principle still stands. If you don't understand why, please look into the uncertainty principle more as well as read the paper closely.
Normally it would not be possible to get this information about the polarization states through a single measurement which is what the article was referring to. You are using "get around" to signify a different operation than that to which the author was referring.
 

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1. So basically if you duplicate a photon into four, then hit four separate electrons with them, all the photons which are entangled effectively entangle them by causing them to all behave the same?

2. How is the universe a simulation? I've heard the simulation argument, but unless you mean the holographic theory of the universe (which is what I described), I'm not sure if one can verify something like this (or refute it truthfully)

3. You know how you can take several two-dimensional images: (Side, top, front, back) and combine them into a 3D image?
 

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This proposition bugs me:
That strikes me as potentially ethically problematic if you end up with a sufficiently complicated system (if you've ever seen the game "Life", even relatively small rules can produce rather complicated results that mimic organic systems...)
The first thing to note is that the system in which Conway's game of life resides in is very simple. It's a grid of cells with only two possible states (dead or alive). CGL mimics life in the sense that the patterns formed in it are unpredictable and capable of exhibiting great complexity. But even its most elaborate structures created come nowhere near close to the complexity of organic systems--really, the gap is like that of Heaven and Earth.

The manner in which Conway's game of life represents information, intrinsically, is extremely limited. Even simpler systems built in CGL appear relatively complex (for example, a universal Turing machine). Further so, the conditions for the emergence of conscious (or even complex) lifeforms depend on very specific criteria--a fine-tuned universe. Here's a nice graphic on that:



The point being, any simulation of a universe potentially inhabited by conscious lifeforms would have to be both extremely complex and hold massive amounts of information, with the added requirement of being specially designed so that complex and conscious lifeforms are even capable of emerging. Plus, if we hope to study such a system, the computer would need to have insane computing power to handle a sufficient amount of information. To put this in more material terms: we'd need more 10^100 qubits to simulate our own universe. Source

Even supposing that the first signs of life appeared in our universe 2-3 million years after the Big Bang, the extended length of time preceding such an event would necessitate that we set our system clock at, say, 1 day per second, to reach that point within 35 years. That's not realistic by any standard.
 

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I'd agree, suremarc, that the machinery required to simulate something on the order of our universe would be truly massive. You might be interested, though, in a slight adjustment of Conway's rules to a continuous floating-point ruleset:

 

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Normally it would not be possible to get this information about the polarization states through a single measurement which is what the article was referring to. You are using "get around" to signify a different operation than that to which the author was referring.
Sorry but even with that one is still not getting around HUP. Why? Because the measurement they used is a weak measurement - no wavefunction collapse occurs. You actually don't know 100% of the information about the state, but you come pretty darn close. The uncertainty that remains is due to HUP. :) Here's some reading about why weak measurement doesn't contradict, and in fact goes hand in hand with, the HUP. Introduction to Weak Measurements and Weak Values | Tamir | Quanta

Weak measurement of polarization has been done in 1991 and in years after that. Nothing really new about this article except its tabloid headline and possible applications to qubits, etc.

To quote the article:

An important result is that a single weak value completely determines the wavefunction of a qubit (see Supplementary Note 2). For a single photon, the weak measurement has very large uncertainty; thus, the above procedure must be repeated on many photons, or equivalently on a classical light beam, to establish the weak value with a high degree of condence.
Do you see now that the HUP is not violated in any way? A qubit is actually a two-state system (aka the two polarization states) and one couples the polarization value to a measurement device. The single weak value is not really a "single measurement". A single weak value is the result of weak measurement.

Here's a study using the same type of measurement in 2011. Tabloids must have missed their chance to hype up this one, a pity. Science Magazine: Observing the average trajectories of single photons

Note about photon entanglement: I don't think it is fair to discuss it without being familiar with the math and the terminology on this page http://en.wikipedia.org/wiki/Photon_entanglement .
 

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I've been watching a bit on Quantum Physics and I find myself wondering, "what is the absolute pinnacle of possibility for this amazing science?" So, I'd like to hear your ideas on this.
Quantum computers! Essentially using the phenomenon of superposition to carry out certain computations in a different way to classical computation & in a few cases incredibly efficiently. Take Peter Shor's use of a quantum computer to calculate Fast Fourier Transforms very rapidly as an example. FFTS have a symmetry that allows them to be split up and carried out in parallel in a manner ideally suited to a quantum computer. A rapid FFT can be used to solve problems like the discrete logarithim problem and the factorization of large integers. The latter can then be used to break a public-key cryptosystem.
 

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I'd agree, suremarc, that the machinery required to simulate something on the order of our universe would be truly massive. You might be interested, though, in a slight adjustment of Conway's rules to a continuous floating-point ruleset:

That's fascinating! Although the information density is probably much higher (at least 8 bits per float), it would seem that that system has much more flexibility with the added degrees of freedom. It also has the added bonus of looking cool :p

I'm no engineer, but I may try and toy around with the program and see if I can build something interesting..
 

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@Diophantine: I understood it. I was saying you were being overly technical for the purposes of RobynC's query. It is enough to know the uncertainty is reduced significantly. The reason I kept my initial answer so succinct was to avoid these sorts of miscommunications. Thank you for the articles.
 

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@suremarc

Reply: 46

1. Cosnciousness isn't really a necessary component of QM; in fact the "observer" is merely an interactor.

2. I don't know how people ever came to believe Science/Ethics are interconnected

Reply: 52

1. The point was simple rules can give rise to complicated systems. A sufficient level of complexity could possibly cross the line.

2. Firstly: Our universe has 10,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 Q-bits in it?

Secondly: If a simulated universe was created, presumably the "outside" universe would have more Q-Bits available

Thirdly: If a simulated universe existed: It could theoretically be much older than the simulated one.


@Creole Neo

What's a continuous floating point?
 

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@Creole Neo

What's a continuous floating point?
Continuous and floating point are separate adjectives applied to the new ruleset. Floating point as opposed to integer, and continuous meaning a continuous count of stuff within a certain radius of the point being measured as opposed to a discrete grid counting only adjacent cells.
 

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@Creole Neo

1. What's a ruleset?

2. What is the point being measured? Could you provide a hypothetical example

3. Could you explain this in a simple way that could be provided to a person who is not a computer science expert
 
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