Brian Cox: Everything Is Connected

Physicist Brian Cox, who is a professor at the University of Manchester and a well-known BBC science presenter, caused a sensation when he was trying to explain Pauli Exclusion Principle in layman's terms on TV.

Here is the segment in the show:



And here is the relevant quote from the segment:

"...but this shift in the configuration of the electrons inside the diamond has consequences, because the sum total of all the electrons in the Universe must respect Pauli. Therefore, every electron around every atom in the Universe must be shifting as I heat the diamond up, to make sure that none of them end up in the same energy level. When I heat this diamond up, all the electrons across the Universe instantly but imperceptibly change their energy levels. So everything is connected to everything else."


Apparently this statement caused quite a stir on the net, especially on Twitter where Prof. Cox was greeted with a flurry of criticisms from physicists and non-physicists alike.

Recently, physicists Ed Copeland and Tony Padilla on the YouTube channel "Sixty Symbols" weighed in on the discussion and here are their views:



In summary, they felt that Prof. Cox should have used the term "quantum state" rather than "energy level", since two electrons CAN have the same energy level.

Prof. Padilla mentioned the example of helium, where two electrons do occupy the same energy level but don't violate Pauli Exclusion Principle because they have different angular momentum.

But both of them felt that there was nothing controversial in what Prof. Cox said; Prof. Padilla thought that the spirit of what he said is OK, while Prof. Copeland enjoyed the TV lecture and expressed surprise that it provoked such a reaction.

He thought that some people might have interpreted the "everything is connected" part as applicable to the connection of human consciousness, which is not what Prof. Cox meant at all.

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Here at Fresh Brainz, we are NOT SURPRISED that this statement could have sparked such a heated debate.

In fact, I see three key parts in what Prof. Cox said that have the potential to generate controversy.

And here they are, in order of increasing intensity:


1. Energy Level

As mentioned earlier, two electrons can share the same energy level but not the same quantum state.

This simply means that no two electrons can have the same four quantum numbers.

Energy level is one of the quantum numbers, but there are three more: angular momentum, projection of angular momentum, and spin.

Prof. Copeland observed that people who notice this technical inaccuracy tend to be physicists.

He defended it by noting that Prof. Cox was speaking to a TV audience who might find the idea of "energy level" novel enough, let alone the concept of "quantum state".

Since these physicists don't consider this a major inaccuracy, I'll have to take their word for it.

Nevertheless, I should mention that the choice of words is important, especially when there are different meanings of the same word in academia and everyday use.

This can't be helped because it is the regular language users, and not scientists, who determine the common meanings of terms, unless it is a new term invented specifically for the science, eg. "quantum state".


2. Everything Is Connected

"Oooooooo..."

I can almost hear the groans from science educators and communicators.

Although Prof. Copeland didn't think there was anything untoward about this assertion, Prof. Cox himself saw it coming:

"This statement received some criticism in scientific circles. Not because it’s wrong, because it isn’t; without this behavior, we wouldn’t be able to explain the bonds that hold molecules together. The problem is that it sounds like woo woo, and quantum theory attracts woo-woo merde-merchants like the pronouncements of New Age mystics attract flies – metaphorically speaking.

For the record, the reason that everything being connected to everything else does not allow us to be, (selects randomly from a pit of drivel), at one with the Universal consciousness, is that the subtle interconnectedness in quantum theory cannot be used to transmit information. Quantum theory, in other words, describes a counterintuitive world, but not a mystical one."


Unfortunately, in popular culture, statements like "everything is connected" are already strongly associated with New Age mysticism.

Supporters of such beliefs immediately interprete it as the "connection" between consciousness, or something like that.

I think they feel that their views are validated when a well-known particle physicist actually said it!

From what I see, much of the negativity on the net is directed against this phrase, and I empathize with Prof. Cox.

Let me explain what I think is going on.

As part of the training, scientists have to give presentations, sometimes to people outside the field who may not understand the significance of their research.

The style of presentation called "zoom-in, zoom-out" is a useful strategy to keep the attention of your audience.

Start with a broad overview, zoom into the technical details, and then finally zoom out again to discuss the wider implications of your work.

Prof. Cox is doing exactly that; by widening the scope to that of the entire Universe, he is trying his best to capture the attention and hopefully the imagination of his audience.

Moreover he is trying to impress on his audience the power of quantum mechanics, which as Prof. Copeland explained, can describe all of the particles with just one wavefunction.

The difficulty here is to choose a statement that has impact so that the audience can have a "take-home message" that is easy to remember.

It might be technically more accurate to say that the electrons in the heated up diamond will affect the quantum state of all other electrons in the Universe, but such a statement clearly lacks the impact of "everything is connected"!


3. Instantly But Imperceptibly

Although many criticisms target the "everything is connected" part, personally I find the part "...all the electrons across the Universe instantly but imperceptibly change..." more contentious, especially the latter bit about "imperceptible change" which I will talk about later.


a. But first, I'll briefly mention the former bit - "instantly".

Dr. Copeland insisted that by "instantly" Dr. Cox didn't mean to say that Einsteinian causality has been violated.

Other people are not so sure.

In an online discussion between physicist Tom Swanson and Prof. Cox, there are people who sought clarification about this.

For example twistor59:

"However in the present discussion we’re talking about a correlation, not just of a spin direction which could give either up or down when you measure it, but in energy levels – energies can be measured, and if my excitation of an electron in London can cause an instantaneous change in an electron energy in the Klingon system, wouldn’t that mean that information can be transmitted instantaneously in principle?"


And Moshe:

"So for example, if you start with such a stationary state and “wiggle” one subsystem, the full system does not have to instantaneously adjust itself so that it stays in a definite energy state. The story is more complicated, and certainly is causal: if an electron 5 lightyears away wiggles, all the electrons in my body will certainly adjust, but not until at least 5 years from now. This is not much different from what happens in classical physics, where we interact in small ways with faraway objects (nor should it be different, physics is classical on those scales)."


Since I'm not an expert in this area, I'll leave it at that.


b. What disturbs me more is the latter part about "imperceptible change".

In that same discussion forum, commenter "The Jab" described it this way (in a very colourful language!):

"As to the validity of his claims, it is indeed true in a trivial way. If QM is correct, and if his model is accurate, then it is true that if he shakes the crystal all electrons in the universe will adjust to it. But there is nothing novel to it. Newton’s theory of gravitation could make exactly the same claim: if Newton flicked a booger in one direction and not another, all planets in the solar system would readjust to it (instantaneously, by the way). As for the claim, it was indeed correct at the time of Newton, and nobody would dispute it then (with the risk of getting some nasty letters from Newton himself). The question is of relevancy for the effect."


JG noted that:

"I think everyone would agree that Cox’s jiggling is not there for all practical purposes, I mean we’re talking about shifts of probability in the many googolplexth decimal place. It’s irrelevant to science in the same way the poincare recurrence theorem is irrelevant to statistical mechanics (maybe even much less relevant)."


And stringph added:

"Hmmm, I would hope that an experimental physicist would place a little more emphasis on what could either in principle or in practice ever be measured.

The difference between physics and pure mathematical or metaphysical speculation is precisely in this point. Asking yourself whether the ‘connections’ have measurable consequences is a great way of clarifying whether they represent any physical reality."


I think these commenters hit an important point in this entire discussion, which is the main reason why this TV lecture makes me feel uncomfortable.

Let me illustrate this with an imaginary scenario.

Suppose I am a counsellor, and my goal is to encourage you to feel good about yourself.

I could say inspirational things like...

"One tiny drop of water will make waves across an ocean."

"If you jump for the sky, you will move the Earth."

"Even a candle in the dark will light up the whole Universe."


And these are not merely metaphors - they are also technically correct, like The Jab's flying booger example.

Backed up by actual (classical macroscale) physics!

But the problem is, I neglected to tell you just how much change has been produced, and whether that change is even measurable.

In other words, these are "imperceptible changes".

Without knowing the size of the effect, the audience would walk away feeling encouraged and empowered; I have inspired them to feel better about themselves using metaphors that are given weight because they are based on technically correct physics.

Since that is my goal as a counsellor, I have succeeded.

However, if I was a science communicator, I did not succeed in conveying an accurate representation of the truth to the audience.

It is not inspirational that everything is connected to everything else... if the connections are practically undetectable.


Would you like to know more?

Critique of Prof. Cox's TV lecture:
- Everything is Connected (by Sean Carroll)

The reason why everyday objects don't pop in and out of existence:
- Quantum Decoherence

More about Quantum Mechanics:
- Power and Strangeness of the Quantum (Public Lecture by Serge Haroche)

Right Round Round Round

Enjoy unsolved mysteries?

Here's one for you: why do people travel in circles when they can't see a fixed landmark?




Apparently, difference in limb lengths doesn't explain this behaviour (eg. driving the car) so this remains an unsolved question.

I wonder if you'll see the same circling movement if you make the blindfolded person lie down on a skateboard, so as to position the inner ear balance organs 90 degrees to the usual orientation.

Or if there is still circling if you give the subject a fixed auditory landmark, like a tall loudspeaker.

Via Mind Hacks.


Would you like to know more?

- A Mystery: Why Can't We Walk Straight? (npr.org)

Gravity Is Just A Theory

Evolution is just a theory. You know what else is just a theory?

Gravity.



There you have it, an object that rolls uphill - "Gravity" has been debunked.

Now buy my snake oil!


Would you like to know more?
- Defying gravity: The uphill roller

Introduction To Jean Baudrillard

Here's a superb primer by globalbeehive to the work of Jean Baudrillard - French sociologist and philosopher best known for his book Simulacra and Simulation, which was misinterpretated by the popular movie, The Matrix.




To a science-trained person, postmodernist philosophy can be very annoying due to the abundance use of metaphors and abuse of scientific jargon.

Moreover, I strongly disagree with the view that the world is fundamentally unknowable - even if "objectivity" can never be reached in practice, we can still distill a high level of intersubjectivity, which for many purposes is good enough knowledge to generate testable predictions and create technologies.

Even so, I think that Baudrillard's observations about the modern consumerist culture are spot on, especially his view on the "sign value" of objects.

Globalbeehive puts it this way:

"For Baudrillard, the sign value is much more important. So you don't just buy a computer to use it, but you also buy a computer in order to prove to the others, in a capitalist system, to make them believe that you are participating in it and have a certain status in it."

Oh my, that is really eerie!

Have you ever wondered why people put up those "Made on a Mac" badges?

Wondered why people spend a quarter million dollars on sports cars, only to drive them through city streets with a 50 km/h speed limit?

Why people spend tens of thousands on high-end audio systems that sound practically the same as those costing ten times less?

The yucky aesthetics of the Bohemian fashion trend in early '09? Bubble skirts? Croc shoes?

Well... now you know!

The consumer doesn't just consume the brand, she also gets subsumed by the brand, and the identity of the person becomes inextricable from the products that she brandishes as signs of her status.

Baudrillard's view on "hyperreality" is also very interesting.

From my perspective, hyperreality is a systems-level, socio-emergent trait that can become more compelling than factual reality.

Hyperreality can be created by distorting or exaggerating certain aspects of factual reality such that it becomes more "real" to the people than reality. This can be reinforced by constantly repeating the message ad nauseum (eg. through media bombardment) and eventually through the mechanism of "normalization of deviance" the people accept the hyperreality as the authentic version.

Or as Baudrillard would say:

"The simulacrum is never that which conceals the truth - it is the truth which conceals that there is none. The simulacrum is true."

This concept is not only of great importance to systems theorists, it is also important to those who are involved in creating the perception of value, for example politicians and sales/marketing people.

**********

I know this is quite a heavy topic to start the New Year with, but heh heh heh... get used to it.

It's going to get even heavier.


Would you like to know more?

About Jean Baudrillard's ideas:
- Excerpt from Simulacra and Simulation (Stanford) *Warning: postmodernist language!

About hyperreality in society:
- War between Business and Science

Not Always About Who You Know...

Check out this superb article "Is the Tipping Point Toast?" (Fast Company article via Mind Hacks) which critiques the concept of "Influentials" in Malcolm Gladwell's The Tipping Point and highlights some of the interesting research data by network theorist Duncan Watts.

Social-networking tools are extensively used in marketing today, stemming from a belief that there exists a small group of highly-interconnected Influentials who play the major role in starting or propagating trends of any sort.

However, this belief is rarely put to a rigorous investigation and the assumption that these Influentials can be identified and targetted is made with the benefit of hindsight.

In fact, studies by Watts suggest the counterintuitive result that random Ordinary people are more likely to start trends than Influentials, and there is no way of telling in advance who that person will be.

He performed an interesting "turn back the clock" experiment (conceptually similiar to Richard Lenski's experiment in evolutionary biology) that was published in Science in 2006:

Watts wanted to find out whether the success of a hot trend was reproducible. For example, we know that Madonna became a breakout star in 1983. But if you rewound the world back to 1982, would Madonna break out again? To find out, Watts built a world populated with real live music fans picking real music, then hit rewind, over and over again. Working with two colleagues, Watts designed an online music-downloading service. They filled it with 48 songs by new, unknown, and unsigned bands. Then they recruited roughly 14,000 people to log in. Some were asked to rank the songs based on their own personal preference, without regard to what other people thought. They were picking songs purely on each song's merit. But the other participants were put into eight groups that had "social influence": Each could see how other members of the group were ranking the songs.

Watts predicted that word of mouth would take over. And sure enough, that's what happened. In the merit group, the songs were ranked mostly equitably, with a small handful of songs drifting slightly lower or higher in popularity. But in the social worlds, as participants reacted to one another's opinions, huge waves took shape. A small, elite bunch of songs became enormously popular, rising above the pack, while another cluster fell into relative obscurity.

But here's the thing: In each of the eight social worlds, the top songs--and the bottom ones--were completely different. For example, the song "Lockdown," by 52metro, was the No. 1 song in one world, yet finished 40 out of 48 in another. Nor did there seem to be any compelling correlation between merit and success. In fact, Watts explains, only about half of a song's success seemed to be due to merit. "In general, the 'best' songs never do very badly, and the 'worst' songs never do extremely well, but almost any other result is possible," he says. Why? Because the first band to snag a few thumbs-ups in the social world tended overwhelmingly to get many more. Yet who received those crucial first votes seemed to be mostly a matter of luck.

Word of mouth and social contagion made big hits bigger. But they also made success more unpredictable. (And it's worth noting, no one in the social worlds had any more influence than anyone else.) So yes, Watts figures, if you rewound the world to 1982, Madonna would likely remain a total unknown--and someone else would have slipped into her steel-tipped corset. "You cannot predict in advance whether a band gets this huge cascade of popularity, because the social network is liable to throw up almost any result," he marvels.

Contingency is important, and the role of Influentials is highly exaggerated.

In any case, I find it curious that both Duncan Watts and I have a similar key criticism of The Tipping Point which I reviewed over three years ago - using a similar metaphor!

Watt's view:

Perhaps the problem with viral marketing is that the disease metaphor is misleading. Watts thinks trends are more like forest fires: There are thousands a year, but only a few become roaring monsters. That's because in those rare situations, the landscape was ripe: sparse rain, dry woods, badly equipped fire departments. If these conditions exist, any old match will do. "And nobody," Watts says wryly, "will go around talking about the exceptional properties of the spark that started the fire."

My view:

Just one match (Maven) in a fireworks factory can blow everything up. You don't need to set up a comprehensive network of fuses (Connector) and detonators (Salesman) first. In contrast, even a hundred detonators would have trouble blowing up a hydroponics farm.

We have both observed that an agent in the midst of change has a tendency to believe that she is the prime mover of the change, ignoring the contributions of others, preconditions in the environment and the vagaries of blind luck.

Counterintuitive Science: Fast Speed, Fat Shape

In popular science fiction, fast spaceships are often shown as streamlined, sharply-pointed vehicles: such as the X-wing in Star Wars or the Colonial Viper in Battlestar Galactica.

Sleekness has long been associated with speed, at least since the dawn of rocket science in the early 20th century.

This is hardly surprising because an aerodynamic shape is necessary to attain high speed on Earth, becoming increasingly important at speeds over 200 km per hour.

By the 1950s, human beings were on the verge of space travel, and the popular conception of a spaceship then (and even now!) for both professional engineers and the general public alike, was the sharp-nosed spaceplane.

A good example of this was the X-15 hypersonic research plane.













Striking resemblance to a you-know-what.

However, the reality that awaited spaceflight enthusiasts was somewhat less svelte...












How did needles turn into fat cones and bells?

It turns out that pointy-nosed spaceships perform well on their way out of the atmosphere, but not when they have to come BACK.

The re-entry speed of a vehicle coming in from low Earth orbit is about 27,000 km per hour (over 7 km per second!) or about 25 times the speed of sound.

Clearly, the vehicle has to lose a lot of speed in order to descend safely into the atmosphere, but how should this be done?

It is impractical for an Earth-launched spacecraft to reduce most of that speed using retro-rockets, since the large amount of fuel required becomes an additional burden to the launch vehicle.

So the returning vehicle must decelerate mainly by atmospheric friction using the atmosphere itself, and this is where the pointy-nose shape becomes a disadvantage.

At hypersonic speeds, a sharp object generates only a thin shockwave, allowing the intense heat of friction compression to come very close to the surface of the object contact the leading surface of the object. Thus, during early wind tunnel tests, the noses of the test vehicles simply melted away.

No known material could withstand such high temperatures.

However, when a blunt object is subjected to hypersonic speeds, due to much higher drag the air molecules ahead of the object cannot move away fast enough. A thicker shockwave forms, acting as a cushion of air that shields the leading surface from much of the intense heat, and lowering peak temperatures to within the limits that can be tolerated by existing materials.

Thus, only with the development of fat re-entry vehicles did human orbital spaceflight become a possibility.

Initially, Russian designers used a cannonball shape for their Vostok space capsule, which could safely re-enter the atmosphere in any orientation, but had a steep ballistic trajectory that was very harsh on the cosmonauts.

They later developed the "bell on a bowl" shape for their Soyuz, while US designers developed the "cone on a bowl" shape for their Mercury, Gemini and Apollo spacecraft. These shapes have a similar function - to provide some lift and self-righting ability, allowing the spacecraft to re-enter with a shallower and more comfortable trajectory.

For 20 years these fat and aesthetically displeasing spacecraft had the counterintuitive honour of being the fastest manned vehicles in history.

Not everyone was satisfied with this and there were numerous designs of spaceplanes (eg. Sänger, Hermes) to replace them, but most of them were unable to proceed beyond test phases.

Then, with the arrival of the US Space Shuttle (1981) and the Russian Buran (1988) the age of spaceplanes appeared to have finally arrived, though with their fat noses and thick bodies neither of them can really be considered sleek-looking. Unfortunately, Buran was cancelled after just one flight and the Space Shuttle is slated to be retired next year.

So for the foreseeable future at least, the vision of a sleek needle-shaped spacecraft stays bogged down in the realm of fantasy, while the cutting edge of real manned space exploration is delivered by the venerable, and fat, space capsule.


Would you like to know more?
- How the Spaceship Got Its Shape (Air & Space Magazine)

Can Delusions Be True?

YouTube skeptic Nykytyne2 discusses the definition of the word "delusion", and some nuances of its meaning.





I like the clarity of his thought process and I find two aspects of his analysis especially interesting.

1. The Importance of Social/Cultural Context on Mental Disorders

Mental illness is often considered to be a problem within an individual himself or herself, but here it is clear from the DSM-IV that social/cultural norms is a major component of the definition of delusion.

Actually, if you think about it further, social norms and expectations are a big part in the definition of any disease!

Imagine a group of people who spend most of their lives in dark caves, searching for food and communicating via sound and touch. Loss of sight due to eye injury would be a minor inconvenience, not a serious pathology.

Conversely, imagine another group of people who for some historical or religious reasons find freckles to be absolutely vile and diabolical. They would shield children from sunlight to avoid the formation of freckles and advocate aggressive treatment once the freckles develop. Scarring caused by freckle removal is more culturally acceptable than the freckles themselves. In such a case, the term "freckles" would be defined as a serious skin condition, a type of disease.

2. The Importance of End Result in Social Perception

I find it fascinating that delusions can be about things that might eventually be shown to be true, like the micro-organism example mentioned in the video. So to Nykytyne2, the thought process is more important than the result when trying to determine if a belief is a delusion.

Still, an army friend once told me, "Money talks. Bullshit walks." For many people, the end result is of paramount importance, whereas the means is not so important or relevant.

But how can you get a "result" without a process?

This differing appraisal of a goal-directed process is very personality-dependent thing; there are people who are impressed by wealth and power and instantly confer respect based on these results, while there are others who cannot confer respect no matter the wealth and power, unless the process used to achieve the results are impressive.

For example -

a. Someone might say: "Hats off to Larry. He caught my heart. He has 12 billion Dollars and is the Head of a big company."

And the other might say: "Hellooo... he is an investment BANKER! He'll tell you lies, and then it's your turn to CRY CRY CRY-Y."

Alternatively -

b. Someone: "She's not an actor, she's not a star. She doesn't even have her own car. Therefore she is a loser, QED."

Other: "Not only that, she also tried unsuccessfully to be a pole dancer. That's why I'm hoping so much she'll stay. And that she'll love me anyway."

**********

Wait, that doesn't sound right.

I wanted to write some sort of MacGyver story for Example b, but I heard singing in my head and wrote that down instead.

Was that an auditory illusion?

*gobbles a handful of pills*

Everybody Cheats... At Least A Little Bit

Interesting talk by MIT behavioural economist Dan Ariely about the psychology of cheating and how it relates to the stock market.






While the observation that morality is heavily dependent on the social context is not new, what really impressed me most is the implication of his experimental results - that a moral code not only helps to regulate in-group behaviour, but also concurrently enhance in-group loyalty via a "Us vs Them" mechanism.

Even if the moral code itself is completely made up!

I don't understand why there is a deep human need to feel morally superior to other people, but this need can clearly be exploited by people who stand to benefit richly from it.

Pipette tip to Mind Hacks.


Would you like to know more?

Another TED talk by Prof. Dan Ariely
- Are we in control of our own decisions?
- Predictably Irrational

Serge Haroche's Talk At NUS

French physicist Professor Serge Haroche came to the new NUS Alumni House last Wednesday to give a public talk entitled "Power and Strangeness of the Quantum".

I think that quantum physics is one of the most misunderstood fields of science in the public perception, so I decided to go to the lecture to learn more about it directly from an expert in this area.

Since it was going to be a public talk, hopefully there won't be too much difficult maths!















As you can see, the turnout for the talk was excellent. This was my first visit to the Alumni House - they have a nice big lecture theatre, which was about three-quarters full on that day.

The crowd was quite varied; there were political dignitaries (I assume from the French Embassy), French-speaking scientists, school kids in uniform and even a Sister in religious dress.















Here's the MC for the evening starting off the event by introducing the Dean of Science, Professor Andrew Wee, who would be giving the welcome address.















In his address, Prof. Wee said jokingly that he was glad that so many people turned up for the talk, even though it was April Fool's Day!

He noted that this talk was part of the 80th anniversary celebrations of the Faculty of Science, which would include many other activities, such as science busking.

He also revealed that the Ambassador of France was in attendance in the audience, which indicates that the invited speaker is a highly respected academic indeed.















Next, Prof. Wee called upon Christian Miniatura, who is a visiting professor at the Centre for Quantum Technologies, to give an introduction about Prof. Haroche's research career.















Here's a quick overview of Prof. Haroche's many academic accomplishments. Note that he has taught in American universities for a number of years - I'll come back to that later.















Next, a photo of the research group where Prof. Haroche was a graduate student. His supervisor Prof. Claude Cohen-Tannoudji would later share the Physics Nobel Prize in 1997.

Prof. Miniatura remarked that Prof. Haroche looked pretty casual at that time, with his hands in his pockets...















Another photo of Prof. Student Haroche at that time, not looking very prominent amongst a big stack of research equipment.

Prof. Miniatura noted that those machines may look antiquated, but our instruments today would also look old-fashioned to our grandchildren.

I should also add that scientific equipment may become faster and better, but one thing will never change - troubleshooting.

Remember kids, if there isn't any troubleshooting, it ain't science!















After the brief introduction, Prof. Haroche was welcomed onto the stage...















... and there was a lolcat right there waiting for him.

But of course.

What did you expect?

Did you really think that you can sit through a lecture on quantum physics without seeing a lolcat?!??

Think inside the box, my friend!















Prof. Haroche began by remarking that seeing those old photos again gave him a bittersweet feeling, because it reminded him of how fast time flies.

I think that the years that he spend in the USA has affected his accent; he sounds less French than Prof. Miniatura.

(I also noticed that French people who have spent too many years in Singapore pick up an amazingly authentic Singlish accent, far more accurate than Americans or Brits. But that's a topic for another time...)

He then pointed out that the famed Richard Feynman quote - "nobody understands quantum mechanics" - should be taken with a grain of salt.

"But just in case you don't learn anything from my talk, at least you're in good company," he joked.

Nice.















Though quantum physics is usually associated with microscopic phenomena, it actually deals with more than 60 orders of magnitude!

As mentioned in the previous slide, quantum law appears at all scales, but at the macroscopic level, it is generally "veiled".

This is an important point that he'll explain in detail later.















As usual, with these sort of scale charts, biological scales are often represented by the DNA double-helix, but never the collagen triple-helix.

It always makes me smirk. Oh well, I'm not a biochemist anyway.

And biologists always appear "sandwiched" between particle physicists and astronomers.

That's fine to me too; it's the stuff in the "middle" that determines the flavour of a sandwich...















This is a public talk where the audience may be more interested in tangible benefits, thus Prof. Haroche spent some time emphasizing the importance of quantum physics to everyday technologies, such as computers...















... lasers...















... atomic clocks (less than one second error over 10 million years!) and GPS systems that depend on them...















... and the quintessential marvel of modern technology - the MRI, which is actually a combination of three quantum technologies.















Now for the maths... time to run and hide!

Not so fast, Prof. Haroche is simply stating that the behaviour of an electron in a hydrogen atom can be described using a wavefunction - a mathematical tool that gives probabilistic results.

Instead of a particle moving in a fixed orbit, the electron is considered to be in a superposition of an infinite number of possible positions.

He noted that Nature has a "wavy" structure. In quantum physics, determinism is replaced by randomness and particles are replaced by wavefunctions.

Apparently Einstein disliked the random aspect of the wavefunction so much that he uttered his famous "God doesn't play dice" quote.















Wavefunctions may sound like mere mathematical constructs, but Prof. Haroche showed us that modern instruments can produce real images of wavefunctions.















Once again, he emphasized that quantum theory is a probabilistic theory.















The essence of quantum strangeness is exemplified by the bizarre phenomenon of quantum interference, which is often demonstrated using Young's double-slit experiment.

When individual particles (eg. electrons) are fired one-by-one through the setup, they hit the target screen at random positions.

As more and more particles pass through, a predictable interference pattern builds up progressively.

But how can there be "interference" if there was only one particle passing through at any one time?















In quantum physics, the wave equation accurately predicts the appearance of the interference pattern.

But Prof. Haroche remarked that classical physicists are not satisfied with that sort of "explanation"...















... they want to know exactly what happened to the particle...















... but the very act of observing the particle disrupts the interference pattern on the target screen!

To me, the easiest way of bending my brainz around this is to think of "observation" here as an active process that can perturb the behaviour of the particle.

Something like how people look away when you shine a bright light in their faces!

More on this later.















Quantum interferences don't just occur spatially, but temporally as well. Interference patterns that appear in time are called "quantum beats".















I'm not going to pretend that I understand the maths behind quantum entanglement.

Suffice to say that once again Einstein didn't like this, calling it "spooky action at a distance", but John Bell found a way to experimentally test it and prove him wrong.















Another strange feature of quantum mechanics has to do with particle identity.

At macroscopic scales, "identical" particles can still be differentiated from one another.















But in quantum systems, identical particles cannot be distinguished from each other. They have no "colours".

Particles can be divided into two categories, based on their interactions with one another: Fermions and Bosons.















Here's a quick overview of the differences between fermions and bosons.

Particle constituents of matter are fermions while intervening particles (such as photons) are bosons.

Got it.















But atoms that are made up of an even number of fermions behave like bosons.

Er... I'm getting a little lost here.















So, depending on the total number of particles in an isotope (including electrons), an atom can behave either as a fermion or as a boson, thus producing a different interference pattern.

I think I understand this.















Now, to me this is the most important slide in the entire talk, because it addresses a key public misunderstanding of quantum physics that is often exploited by New Age woo-meisters.

Can quantum strangeness occur to macroscopic objects?

Erwin Schrödinger once posed this question as a thought experiment: the infamous Schrödinger's Cat (referenced in the lolcat slide earlier) which has become sort of a mascot for quantum strangeness.

Schrödinger was thinking of a way to transform a superposition inside an atom to a large-scale superposition of a live and dead cat by coupling the cat and atom using a specially constructed device.

He wanted to critique the Copenhagen interpretation of quantum mechanics by illustrating the absurdity of its consequences.

Wikipedia describes this concisely:

A cat, along with a flask containing a poison, is placed in a sealed box shielded against environmentally induced quantum decoherence.

If an internal Geiger counter detects radiation then the flask is shattered, releasing the poison which kills the cat.

Quantum mechanics suggests that after a while the cat is simultaneously alive and dead.

Yet, when we look in the box, we see the cat either alive or dead, not a mixture of alive and dead.

Prof. Haroche explained that quantum strangeness usually does not happen to macroscopic objects precisely because of decoherence: the environment gets entangled with the system and destroys quantum superpositions.

He said that you can consider it as the environment "spying" on the cat.

Decoherence becomes faster as the system size increases, thus macroscopic objects behave in a more intuitive, classical manner.















Schrödinger did not expect anyone to actually test his thought experiment, but today physicists have the tools to fight decoherence and it is now possible to do the imaging of isolated trapped atoms...















... see microwave photons...















... and even set up a photonic version of the Schrödinger's Cat experiment.

Here, the purple feature under the disk corresponds to the "cat state" quantum coherence.















As decoherence effects set in, you can see the purple feature gradually disappear from the field diagram as the quantum system is transformed into a classical system (towards upper right).















Prof. Haroche then proceeded to talk about new quantum technologies on the horizon.

An exciting new field of quantum computing is emerging and has the potential to be much faster than current technology.

However, he cautioned that building a large practical quantum computer is very difficult because of decoherence.

A simpler application of quantum entanglement is in cryptography - used for the purposes of secure communications. This technology is already available on the market.















In his last slide, Prof. Haroche turned to his attention to the question of whether a second "quantum revolution" is approaching.

He speculated that we might see new applications in the future that we can't even dream about today.

As a concluding message, he encouraged young scientists to let their curiosity drive their research and not to be obsessed with the quantum computer, but quickly added "as long as the funding agencies permit it".

He joked: "That is our tragic position in life."

With that, he ended his talk and it was time for the Q&A session!

I asked the first question of the evening, and not surprisingly it was:

"What popular misconception of quantum physics in the public annoys you the most?"

Prof. Haroche replied that he especially disliked the abuse of quantum physics in discussions of consciousness or free will, because those processes operate at an "overwhelmingly classical" level.

Later, a member of the audience stood up and commented: "I'm just a layman but now I know where the term 'quantum leap' comes from!"

Then there was a question about quantum tunneling, and Prof. Haroche proceeded to give a quick overview of that effect.

I think the best question of the evening came from a young man who asked:

"There are now numerous interpretations of quantum mechanics. Which interpretation do you prefer?"

Prof. Haroche conceded that it was a good question - he was aware of physicists who were adamant that quantum mechanics does not "need" interpretations and that the mathematics was all that you needed.

He used to subscribe to that view, but confessed that as he got older, he appreciated interpretations more. Still, he thought that it could be an "endless game" since our intuition is simply unable to understand quantum mechanics.



















After all that heavy intellectual "food" it was time to stuff my face with some real "classical" stuff!

It was Thai food, and you can see that there was a good spread.

As I munched on my dinner, I was thinking about decoherence due to environmental entanglement and how it vastly simplifies the behaviour of macroscopic objects, which fits nicely into my FAMILIAR model.

Maybe I'm really on to something...


Would you like to know more?

Other lectures by prominent academics:
- Bruce Alberts At The Biopolis
- Embryonic Stem Cell Lecture (Prof. Martin Evans)
- Early Detection Is Your Best Bet (Prof. Lee Hartwell)

Chick Tracts In Singapore

An interesting news in the Straits Times today:

Offensive booklet reported

By Elena Chong

A MUSLIM administrative manager said she felt offended and angry after reading a small anti-Islamic booklet sent to her by post.

Madam Farhati Ahmad, 36, said she received the comic book called The Little Bride through the mail at her Woodlands home on March 6, 2007.

After reading the contents of the booklet, published by Chick Publications, an American Protestant publisher, she made a police report the same day.

She did not know who sent it but suspected that a Christian organisation had done it. She said she felt very insulted by the booklet whose objective was to insult and confuse Muslims.

'I also feel that its intention was to instigate feelings of anger or hatred for Islam as a religion,' she said.

She was testifying at the third day of the trial of technical officer Ong Kian Cheong, 50, and his wife, Dorothy Chan Hien Leng, 45, an associate director with a bank, on charges under the Sedition Act and Undesirable Publications Act.

The Christian couple are alleged to have distributed a seditious publication each to two men, and the objectionable publication to Madam Farhati between March and December 2007.

The charges say the publications had the tendency to promote feelings of ill-will and hostility between Christians and Muslims in Singapore.

When Deputy Public Prosecutor Anandan Bala asked why she made a report instead of throwing the booklet away, Madam Farhati said if the publication which she described as dangerous were to fall into wrong hands, it might disrupt racial harmony in Singapore. She also said people could use it to cause harm and chaos.

The other two Muslims who made police reports after receiving The Little Bride and Who Is Allah? are Mr Irwan Ariffin, 32, and Mr Isa Raffee, 35.

The hearing continues.

Click this link (Booklets available in store) for more details about this trial, where the defence lawyer argued that distributing Chick tracts is not an offence because they are freely available in places such as the Tecman bookshop.

**********

Chick tracts are nothing new in Singapore. I'm sure that many of my readers would have encountered them in one form or another, especially classic ones such as "This Was Your Life".

I recall that I was given one as a teenager - I was flying model gliders near the void deck of my flat when a military officer came up to me and offered the tract to me. I suppose he felt that I was good material for "salvation" and gave it to me on good faith, but when I read the contents of the tract, I found it to have a very simplistic, biased and threatening tone.

Chick tracts are a straightforward conversion tool - every one of them ends with a statement compelling the reader to convert. Thus there is no discussion of nuance or alternative interpretations and explanations within.

To make his case in a small pamphlet with only a few pages, Jack Chick employs a sledgehammer approach and simply attacks everyone with beliefs other than his own, hoping to win converts via doubt, shock and fear. I'm not surprised that someone will eventually be offended by these tracts, I just wonder why it took so long.

The government will most likely resolve this issue using censorship, but I suspect that this might increase the secret appeal of the tracts instead.

In some other countries, Chick tracts are simply deconstructed, refuted and spoofed into irrelevance. I don't know if that would work in Singapore, but personally I would prefer to see an open discussion of such issues rather than the short-term solutions of legal action and censorship.