Tuesday, January 29, 2013

Why Not Both

a hard look…

Toward a Fully Relativistic Theory of Quantum Information
Christoph Adami
Michigan State University, Depts. of Physics and Astronomy/Microbiology and Molecular Genetics.

Entropy and Information are statistical quantities describing an observer’s ability to predict the outcome of the measurement of a physical system. Because an observer’s capability to make predictions is not a characteristic of the object the predictions apply to, it does not have to follow the same physical laws as those befitting the object. Thus, the arrow of time implied by the loss of information under standard time-evolution is even less mysterious than the second law of thermodynamics, which is just a consequence of the former.
[mentioned in reference to the information loss paradox of the black hole]

Entropy…Shannon Entropy
Entropy quantifies the ability of observers to make predictions; in particular how well an observer equipped with a specific measurement apparatus can make predictions about another physical system.
[a measurement of measurements]

For Shannon entropies, or uncertainties, we only need to quantify our uncertainty about the possible outcomes of a measurement [read: quantification] of that system. (No need to consider the impossible outcomes.)

i.e. “An observer’s maximal uncertainty about a system is not a property of the system, but rather a property of the measurement device with which the observer is about to examine the system.”

By subtracting the uncertainty given by a measurement device from the maximum potential uncertainty for the measured system, we get information.

The maximum potential uncertainty is potential information (how much is knowable).

“If my actual entropy vanishes, then all of the potential information is realized.”

Quantum Entanglement Theory
-occurs between the system being measured and the measuring apparatus, which makes them one system, not a composite.

“Selves do not exist anymore after entanglement.”

After entanglement, the system grows to QA (not Q). Thus the detector is asked to describe a system (Q) larger than itself because by its very measuring-of-the-system (A) it makes the system (Q) include itself: (QA).

This non-separability of a quantum system and the device measuring it is at the heart of all quantum mysteries.

A quantum measurement is self-referential, since the detector is asked to describe its own state, which is logically impossible.

a wider view…

I think I can safely say that nobody understands quantum mechanics.
-The Feynman Lectures on Physics, 1964, Ch. 6, “Probability and Uncertainty"

All Things Quantum – duality, The Observer, the Uncertainty Principle, the simultaneous occurrence of all possible worlds, the renunciation of causality – are counter-intuitive. It is a world where certainties have been reduced to probabilities.

Quantum, the word, comes from ‘quantity’, or ‘how much’. Quantum Satis: “The amount which is needed”. It refers to the smallest quantity by which we are able to measure things. It only relates to things which happen to subatomic particles, or at extreme temperatures. The Photon, for example, is a single quantum of light, called the “light quantum”. In neurology, it refers to a fundamental unit, or discrete component, of physiological response.

In general, but still from a scientific view, ‘quantum mechanics’ helps us to categorize certain phenomena that cannot be explained using classical physics, those being both Newtonian and Relativistic, (as the latter is for big things, not small).

The Dual Processing System of Memory and Perception

In brain science, the idea of ‘quantum mind’ has been mostly cleared up and given way to ‘quantum cognition’. The neurons of the brain do not function by way of quantum mechanics; the software, however, seems to. The cognitive system can be seen as using non-probabilistic, or quantum decision-making processes, resulting in emergent properties of concept accumulation/combination, memory, judgment and perception.

the hall of mirrors…

"If all potential ‘things’ stretch out infinitely in all directions, how does one speak of distance between them, or conceive of any separateness?"
-Zohar, p. 17-18

Vector States_kevindooley-flickr

Quantum is neither here nor there. The electron is not here; it’s in this general area. Chances are, if you look in this area, you’ll find it. Quantum is fuzzy. It’s about not-knowing for sure. Quantum is not about measurement, and that is the confusing part. Is it or not? And under what conditions will it be more likely to be, than not?


Too many people are making up their minds about what ‘quantum’ means, in their own ways, in crystal clarity, or tangled knots, all of them. Whatever it is – this word, this thing – it is only what everyone says it is.

The impact of quantum physics, it seems, comes from its measuring not of things dimensional, like sub-atomic particles, but of information. Discrete, or small, is a reference to the amount, not of space or time, but of information: yes or no, on or off. To reduce a system – an information system – to this resolution – two possible answers – allows us to measure it discretely. It’s not even a measurement of things anymore, but things yet-to-be!

This word, then, that which makes it so mysterious and so misinterpreted is its reference to things not of our world.

“Nothing is fixed or fully measurable, everything remains indeterminate, somewhat ghostly, and just beyond our grasp”
-Zohar, p. 11

We aren’t measuring things-that-are anymore, but the potential possibilities of things. Experiments of this nature, in both lab and mind, are conducted in the future; they are a simulation of a future (not the future). It is experimentation with potentialities, not with things.

Here is the fixation – this premise that we not only can predict, but create the future, is suspicious, to say the least. But we do this all the time. If a brick is sailing towards your face, you predict it will hit you, and you move aside. You look at the probable futures, and you choose one. But even analogy is dangerous in this prospect of questioning the quantum world.

“The world doesn’t exist until you say it does, and somehow that means you can make it whatever you want.” How did we get here? From measuring data to flexing superpowers? But there is a tempered middle becoming less ignorable. Creeping into our social behaviors and our everyday technology alike, forcing us to make sense, not of what quantum theory means, but what it means to all the people who don’t know what it means.

Zohar, D. (1990). The quantum self: a revolutionary view of human nature and consciousness rooted in the new physics. London: Bloomsbury.


Quantum Superposition
 ...fundamental principle of quantum mechanics that holds that a physical system—such as an electron—exists partly in all its particular, theoretically possible states (or, configuration of its properties) simultaneously; but, when measured or observed, it gives a result corresponding to only one of the possible configurations (as described in interpretation of quantum mechanics).

Networks are scale-free:
On the extreme separation of scales at which both quantum mechanics and relativistic gravity work.

Quantum teleportation between atomic ensembles demonstrated for first time
Lisa Zyga, November 19, 2012

One of the key components of quantum communication is quantum teleportation, a technique used to transfer quantum states to distant locations without actual transmission of the physical carriers. Quantum teleportation relies on entanglement, and it has so far been demonstrated between single photons, between a photon and matter, and between single ions. Now for the first time, physicists have demonstrated quantum teleportation by entangling two remote macroscopic atomic ensembles, each with a radius of about 1 mm.

Quantum teleportation between remote atomic-ensemble quantum memories
Xiao-Hui Bao, et. al. Edited by Alain Aspect, Institut d'Optique, Orsay, France, and approved October 11, 2012

Will we ever understand quantum theory?
Philip Ball, 25 January 2013, BBC Future

Many outsiders figure that they don’t understand quantum theory because they can’t see how an object can be in two places at once, or how a particle can also be a wave. But these things are hardly disputed among quantum theorists. It’s been rightly said that, as a physicist, you don’t ever come to understand them in any intuitive sense; you just get used to accepting them. After all, there’s no reason at all to expect the quantum world to obey our everyday expectations. Once you accept this alleged weirdness, quantum theory becomes a fantastically useful tool, and many scientists just use it as such, like a computer whose inner workings we take for granted. That’s why most scientists who use quantum theory never fret about its meaning – in the words of physicist David Mermin, they “shut up and calculate”, which is what he felt the Copenhagen interpretation was recommending.

Physicists propose measure of macroscopicity; Schrodinger's cat scores a 57
Apr 26, 2013 by Lisa Zyga

The size of an object can be measured in many ways, such as by its mass, volume, or even the number of atoms it contains. And when it comes to quantum physics, "macroscopic" objects are considered to be larger than "quantum" ones, since the former are usually described by classical laws and the latter by quantum laws. However, physicists have been challenging the boundary between these two realms by performing experiments that show that multiparticle objects can exist in quantum superpositions. But there has been no standard measure of macroscopicity until now, as a team of physicists has proposed that the macroscopicity of an object can be measured in terms of certain parameters of the experiment used to probe its quantum superposition, rather than as a single property of the object itself.

Physicists Stefan Nimmrichter of the University of Vienna, Austria, and Klaus Hornberger of the University of Duisburg-Essen, Germany, have published a paper on the new definition of macroscopicity in a recent issue of Physical Review Letters.
Macroscopicity of Mechanical Quantum Superposition States, linkarxiv

just the intro to a relevant article:
One of the most basic laws of quantum mechanics is that a system can be in more than one state – it can exist in multiple realities – at once. This phenomenon, known as the superposition principle, exists only so long as the system is not observed or measured in any way. As soon as such a system is measured, its superposition collapses into a single state. Thus, we, who are constantly observing and measuring, experience the world around us as existing in a single reality.
Researchers suggest one can affect an atom's spin by adjusting the way it is measured
phys.org, Mar 18, 2013

New scheme for quantum computing
phys.org, Jun 25, 2013

The trick is to design algorithms so that wrong answers cancel out and correct answers accumulate. The nature of those algorithms depends on the medium in which information is stored.

Meyer and Wong considered a computer based on a state of matter called a Bose-Einstein condensate. These are atoms caught in an electromagnetic trap and chilled so cold that they "fall" into a shared lowest quantum state and act as one.

Tom Wong, graduate student in physics and David Meyer, professor of mathematics at the University of California, San Diego

Uncovering quantum secret in photosynthesis
phys.org, 20 Jun 2013

Watch the process of photosynthesis closely enough – at the femto-scale – and it appears there are little packets of energy simultaneously "trying" all of the possible paths to get where they need to go, and then settling on the most efficient.

In an article published in the journal Science, researchers from ICFO- Institute of Photonic Sciences, in collaboration with biochemists from the University of Glasgow, have been able to show for the first time at ambient conditions that the quantum mechanisms of energy transfer make photosynthesis more robust in the face of environmental influences.

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