Crisis

Is quantum physics weird?

 

quantum physics wierd

quantum

Why quantum physics is believed to be so weird? Can we understand it without reading tons of scientific formalism? The answer depends on the incentive behind the question;

What people mean by saying that quantum physics is weird? Let’s see some possible reasons;

Formalism

Is it because you cannot understand the formalism? The formalism itself is not weird; maybe it is hard besause you are not so familiar with the mathematics behind it.

Insight

Is it because you cannot get the physical insight behind it? Then welcome to physics; the hardest part in any physics discipline is not to use the mathematics, but to develop an intuitive understanding by grasping the insight of the theory. This ability is very hard to be taught.

Uncertainty

Is it because you cannot accept the philosophical implications of quantum physics? Then we have you have to clarify a little more; What do you mean by philosophical implications? Is it that you are worried that the famous cat cannot be both dead and alive in the same time¹? Which means that you don’t like the innate uncertainty that quantum physics is introducing? In this case you assume that classical physics does not lead to any cats that they are dead and alive in the same time. But is this really true?

Classical physics

Classical physics is a study of how things, like stellar objects and planets, can move relative to one another in a regular fashion. In the language of classical physics, in order that we can have a theory about a certain subject matter we must presuppose that we already have two things in place;

a) We must have a kinematical framework in which we can define how the things to be studied might be distributed in space and time

b) We must have a dynamical understanding of the powers and properties that might successively occupy specific places in space.

The first framework is provided by the Cartesian analytic geometry. The second framework is provided by Newtonian laws, which they describe the evolution of things in space and time.

quantum physics wierdClassical physics offers a very important promise; if we know the initial state parameters of a system, theoretically, we can solve the equations that describe the dynamics of the system and  know the full behavior of the system in the past and the future. In simple worlds it means that if your cat is missing then if you put all the parameters of the system in a super computer that solves the dynamics of the world that you live in, you can find out with 100% certainty if your cat is dead or alive. The cat cannot be both dead and alive in the same time.

But there are some objections there;

1. Chaos: Even if a system is deterministic it cannot be 100% predictable, and that is because you can not measure the initial state parameters with infinite accuracy.

2. Complexity: Let’s assume that we don’t care about chaos, because we  have found a way to measure with infinite accuracy. Then we face some problems that they derive form computer science; How long will it take for this super computer to decide if the cat is dead or alive? If it takes more that a cat’s life time then we don’t need to perform the calculation because the cat is 100% dead. The problems is now transformed from pure physics to pure computational complexity.

3. Let’s assume now that we are lucky and the complexity of the calculations is not a problem (we have a super computer, and the equations of the dynamics of the world is an easy problem). Even in the situation that we can we really solve the equations for the whole universe and find out the position and speed of every single elementary particle of the world at any given time, can we really sort this kind of information? Imagine that we are talking about all the elementary particles of the world, even for a single snapshot you have a problem of storage; since the unit of storage cannot be smaller than one elementary particle! You cannot even describe a single snapshot of the universe , which means that there are points in the universe that you are uncertain of their properties. Maybe you can calculate if the cat is alive but then you cannot know what is the situation of all the cats in the universe!

So uncertainty can’t be the reason that quantum physics is considered weird.

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Posts and news on science

Interesting posts

Beyond God and atheism: Why I am a ‘possibilian’

But good science is always open-minded, and the history of science is one of surprises and overturnings. Science is nothing but careful thinking, and careful thinking encourages an appreciation of the complexity of the world. The complexity encourages us to maintain several possibilities at once. In a single lifetime, we may have no way to remove the ambiguities from these possibilities.

News

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Scientists isolate, hold, photograph individual Rubidium 85 atom

(PhysOrg.com) — In a major physics breakthrough, University of Otago scientists have developed a technique to consistently isolate and capture a fast-moving neutral atom – and have also seen and photographed this atom for the first time.

Random numbers created out of nothing

Now Christian Gabriel’s team at the Max Planck Institute for the Science of Light in Erlangen, Germany, has built a prototype that draws on a vacuum’s random quantum fluctuations. These impart random noise to laser beams in the device, which converts it into numbers.

Sound can leap across a vacuum after all

Now a theoretical analysis by Mika Prunnila and Johanna Meltaus, both of the VTT Technical Research Centre of Finland in Espoo, suggests that sound may be able to leap across a vacuum separating two objects made of piezoelectric crystals. These crystals generate an electric field when squeezed or stretched by sound waves or other forces, and deform in an electric field.

Biology

Study shows real partners are no match for ideal mate

Our ideal image of the perfect partner differs greatly from our real-life partner, according to new research from the University of Sheffield and the University of Montpellier in France. The research found that our actual partners are of a different height, weight and body mass index than those we would ideally choose.

Unlocking the secret of beauty: Scientists discover the complexities of attractive female bodies

Scientists in Australia and Hong Kong have conducted a comprehensive study to discover how different body measurements correspond with ratings of female attractiveness. The study, published in the Journal of Evolutionary Biology, found that across cultural divides young, tall and long armed women were considered the most attractive.

Do we really understand Science?

do we really understand science?Science is not isolated from society; scientific discoveries can be an important reason for social changes. For example the discovery that earth is not flat influenced not only the scientific society but the whole world-view of the educated members of the society and helped in the separation from the Church . Philosophy was always inspired by technological innovations and scientific discoveries. Actually, someone can say, that Philosophy itself  is a by-product of the technological achievements in sea commerce; in ancient Greece trading provided people with massive new experiences that lead them to independent thought.

Philosophy and science should go hand in hand; Philosophers should decode the “true” meaning behind scientific discoveries and lead society to world-view change.  But this, of course, in not always the case or at least it doesn’t happen for the last couple of centuries. According to the humanists there is a big failure of philosophy in the latest years;

Dewey concluded that most of the problems of society during the nineteenth and twentieth centuries stemmed from the colossal failure of philosophy. He claimed that philosophers had forsaken their responsibility to explain the findings of science as they came to light, and to provide leadership in the continuous forging of a world view compatible with those findings–that they had, instead, lost themselves in the “quest for certainty.” The result was that much of the intellectual progress of the Enlightenment era stagnated and even regressed with the reemergence of a belief system that, once again, divided the world in two.

The reason for this failure is what they call “dualism”; Philosophers tried hard to reconcile science and religion by separating matter from “soul” which actually means to prevent science of studying humans as a part of nature.  If we describe thinking as another expression of Nature then there is no absolute truth and certainty any more.

Altogether, Kant provided a world view within which science was itself a quest for certainty –but a quest appropriate only for “the inherently rational and immutable domain of material substance.” As for that realm of change for which the methods of science are not applicable, humans were advised to rely on faith in metaphysical explanations, with their promise of escape from uncertainty through the soul’s ultimate connection to a realm of perfect being.

Dualism is the reason that Darwin’s theory was under attack for so long; This scientific theory treats humans and their “soul” as a part of Nature, and “dualists” cannot allow that.

For well over a century we have witnessed a battle, virtually to the death, to fence off psychological, anthropological, and sociological studies from that remarkable ordering paradigm now providing the very foundation for our understanding of all living things. This war has been fought not only by theologians but by many established academics in the humanities and so-called hard sciences. If it could be shown that evolution has no implications whatsoever for the spiritual and practical realms–that is, for human emotions, values, ideals, and actions–then the long-established reconciliation of religion and science in our culture need not be endangered.

The growing distance between dominant philosophy and the the philosophical suggestions that derive from scientific discoveries, creates a barrier to science itself;

No wonder we are producing so many mystics who throw all criteria for truth claims to the winds, while crying blithely, “All, all is mystery. We must learn to live with contradiction–to intuitively `know’ the unknowable!”. We tend to be satisfied only if a particular truth claim or value makes sense in terms of what we already believe–that is, if it fits into our current “meaning frame.”

What “dualists” refuse to abolish is certainty and  the idea of “absolute truth” behind scientific discoveries. Humanists, and evolutionary science in general, accept that we are bound to our nature and that our quest for knowledge is a gift that evolution gave to us. We are developing scientific methods because we evolved this way, yet we cannot handle the world views that Science suggests!

A very good demonstration of the problem can be the example of Relativity; Special theory of relativity is based in the assumption that there is no special system of reference in this world, there is no aether. But still people want to think that they hold a unique position in the Universe; that they are the only “intelligent” life form, even if the theory of Relativity suggests that time is bound to space which means that there are limitations on what we can learn about the universe (light cone), and that there can be parts of the vast universe that we cannot experience.

Another example is the one described in the post below; (In physics we can have two theories that describe the same world and they can be both correct)

http://www.science20.com/alpha_meme/duality_%E2%80%93_world_has_no_dimensionality_all

So let us put it yet again in another, more pointed way: There is a surface of N dimensions without general relativity, the stuff of which obeys some rules that allow for evolution and all that, only to end up with conscious systems that argue in all earnest that the world fundamentally must have N+1 dimensions and that anybody who does not pledge full allegiance to general relativity as the fundamental last answer is a total quack and has no place in science or philosophy.
This is basically the state of the world today, and the especially sad part is: we already know this for quite a number of years by now, but at least my entire generation has to first bite the grass before it is widely accepted. As always, progress goes on funeral by funeral, established philosophers are mostly windbags, and pop-science sells via time-travel and worm-holes, but fails to communicate insights.

So the question is; do we really understand science or we like to believe that Earth is still flat?

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Related questions/discussions

The Importance of Understanding Science

Why don’t Americans understand science better? Start with the scientists.

Why We Need To Understand Science

Related Books

Can we understand science?

References

http://findarticles.com/p/articles/mi_m1374/is_4_61/ai_76800134/?tag=content;col1

http://www.wikipedia.org/

http://www.science20.com

Maxwell’s demon at work: information-heat engine

The second law of thermodynamics is considered to be one of the “strongest” laws of Nature.

The second law of thermodynamics ensures (through statistical probability) that two bodies of different temperature, when brought into contact with each other and isolated from the rest of the Universe, will evolve to a thermodynamic equilibrium in which both bodies have approximately the same temperature. (.)

Right away by reading the above definition we understand that the second law of thermodynamics has to do with statistics. In schools we learn that the 2nd law of thermodynamics is the expression of the axiom of conservation of energy, and that is the reason that it is so “strong”. What they don’t teach us is that conservation of energy is a statistical phenomenon that we experience in the macroscopic world, despite that this was demonstrated 150 years ago by James Clerk Maxwell with his famous demon thought experiment;

second law of thermodynamics.. if we conceive of a being whose faculties are so sharpened that he can follow every molecule in its course, such a being, whose attributes are as essentially finite as our own, would be able to do what is impossible to us. For we have seen that molecules in a vessel full of air at uniform temperature are moving with velocities by no means uniform, though the mean velocity of any great number of them, arbitrarily selected, is almost exactly uniform. Now let us suppose that such a vessel is divided into two portions, A and B, by a division in which there is a small hole, and that a being, who can see the individual molecules, opens and closes this hole, so as to allow only the swifter molecules to pass from A to B, and only the slower molecules to pass from B to A. He will thus, without expenditure of work, raise the temperature of B and lower that of A, in contradiction to the second law of thermodynamics….

One better understanding of the second law of thermodynamics is through entropy¹;

The second law of thermodynamics states that the total entropy of an isolated system must increase. Since the demon and the gas are interacting, we must consider the total entropy of the gas and the demon combined. The expenditure of energy by the demon will cause an increase in the entropy of the demon, which will be larger than the lowering of the entropy of the gas. (.)

The demon will consume energy and increase the energy of the whole system, so the second law of thermodynamics is safe again. But it really depends on what this demon is; what about if the demon does not increase the entropy of the system by operating in thermodynamically reversible² way?

In 1960, Rolf Landauer suggested these “reversible” measurements could be used to sort the molecules, violating the Second Law. (.)

The second law of thermodynamics is not safe again, and in order to defend it we have to understand what entropy really means;

In information theory, entropy is a measure of the uncertainty associated with a random variable. The term by itself in this context usually refers to the Shannon entropy, which quantifies, in the sense of an expected value, the information contained in a message, usually in units such as bits. Equivalently, the Shannon entropy is a measure of the average information content one is missing when one does not know the value of the random variable.(.)

Taking in account the above definition of entropy, then the arguments in favor of the second law of thermodynamics replace energy with information;

In 1982, Bennett showed that, however well prepared, eventually the demon will run out of information storage space and must begin to erase the information it has previously gathered. Erasing information is a thermodynamically irreversible process that increases the entropy of a system. (Many people run into this problem of running out of storage space on their own computers but fortunately there is a simple solution – deleting some of the unnecessary data. A Maxwellian demon could do the same thing, deleting earlier data. But memory erasure is by definition an irreversible process. Once you’ve deleted the data on a piece of memory, resetting all the bits to 0, it is impossible to reconstruct the original data from this string of 0s. This irreversible process increases entropy by k ln 2 per bit. Bennett realised that one bit of storage was needed for each Szilard cycle. The entropy increase when these bits are erased offsets the entropy decrease effected by the demon.(.)

Despite that even this argument does not “save” the second law of thermodynamics ³ it achieves an important transformation; energy is replaced with information, and the quest of defending the second law of thermodynamics can be understood in terms of information exchange.

Finally 150 years later scientists and engineers managed to create the first implementation of Maxwell’s demon; Physicists Convert Information Into Energy For the moment they don’t seem to care about the quest of defending the second law of thermodynamics, they are excited because they have a principle for creating a nano-scale engine that converts information to energy.

Update 30 Sep 2010

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If you read  the article carefully it seems that the “conversion of information to energy” is not the case exactly;

It’s hard to overstate the significance of what they’ve done: they’ve been able to operate a nanomachine–a stair-climbing bead–using nothing more than information as the power supply. (.)

The camera is observing the bead and stops it from moving back downstairs, by changing the electrical field action that implies consumption of energy. Until they replace the macroscopic camera with something else that does not consume energy the second law of thermodynamics is safe from this challenge. (thanks flaredOne)

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¹Entropy is a macroscopic property of a thermodynamic system that is a measure of the microscopic disorder within the system. It is defined by the second law of thermodynamics. Thermodynamic systems are made up of microscopic objects, e.g., atoms or molecules, which carry energy. According to the second law of thermodynamics, the thermodynamic entropy is a measure of the amount of energy which does no work during energy conversions.

²In thermodynamics, a reversible process, or reversible cycle if the process is cyclic, is a process that can be “reversed” by means of infinitesimal changes in some property of the system without loss or dissipation of energy. Due to these infinitesimal changes, the system is in thermodynamic equilibrium throughout the entire process. Since it would take an infinite amount of time for the reversible process to finish, perfectly reversible processes are impossible. However, if the system undergoing the changes responds much faster than the applied change, the deviation from reversibility may be negligible. In a reversible cycle, the system and its surroundings will be exactly the same after each cycle.

³ John Earman and John Norton have argued that Szilárd and Landauer’s explanations of Maxwell’s Demon begin by assuming that the second law of thermodynamics cannot be violated, thus rendering their proofs that Maxwell’s Demon cannot violate the Second Law circular. (.)