Science – Page 5 – Me on the net

Seasons (again)

This is a bit of a repeat, since I almost forgot about writing this week. I decided to revisit the seasons thing.

English: Kukulkan at its finest during the Spr... — English: Kukulkan at its finest during the Spring Equinox. Chichen Itza Equinox March 2009. The famous descent of the snake at the temple. (Photo credit: Wikipedia)

We have just begun the season of Southern Hemisphere spring. This officially starts on 1st September and runs through to 1st December. Then summer starts and runs through to 1st March, then autumn runs through until 1st June, and winter extend to 1st September and the cycle repeats.

The reason that the seasons are defined like this goes back to 1780 when an organisation called “Societas Meteorologica Palatina” defined them as above. The organisation chose those dates because the seasons pretty much aligned with those dates in terms of temperature and rainfall and so on. The coldest three months in the Northern Hemisphere tended to be December, January and February, the warmest tended to be June, July and August, and so on.

Since the seasons are reversed in the Southern Hemisphere, the southern cycle is as described above. We have Christmas on the beach and spend July wrapped up and close to any source of heat!

Astronomers do it differently. They divide the year into four seasons, but the seasons are not aligned climatically, but are defined relative to the Earth’s position in its orbit around the Sun.

Because the Earth’s axis is tilted relative to its orbit around the sun, the axis is be tilted towards the sun at one time of the year and away from it six months later. When the axis is tilted towards the sun, the sun is at its highest in the sky and more energy is received on Earth per square metre than at any other time of the year. It’s summer and warmer. When it is tilted away, the sun is at its lowest and we receive less energy than at any other time of the year. It’s winter and colder. (But read on).

On Earth, when the sun is high it is in the sky longer than when it is lower. The day is therefore longest and the night is the shortest in the yearly cycle. When the sun is midway between its highest and its lowest, the day and the night are of equal length.

English: Midnight Sun in Tromsø, seen from the... — English: Midnight Sun in Tromsø, seen from the old port. (Photo credit: Wikipedia)

The time when the sun is highest or lowest in the sky is called a “solstice“, either a winter solstice, or a summer solstice. The times when it is half way are called “equinoxes“, either an autumnal equinox or a vernal equinox, and the night and day are equal in length. These are the four main signposts of the seasons, as used by astronomers.

Strictly speaking, to say “Today is the summer solstice” or “Today is the autumnal equinox” are incorrect. Since the day and night lengths are changing all the time, the solstices and equinoxes are points in time, not whole days.

English: Two equinoxes are shown as the inters... — English: Two equinoxes are shown as the intersection of the ecliptic and celestial Ecuador, and the solstice’s times of the year in which the Sun reaches its maximum southern or northern position. Español: Se muestran los dos equinoccios como la intersección del ecuador celeste y la eclíptica, y los solsticios momentos del año en los que el Sol alcanza su máxima posición meridional o boreal. (Photo credit: Wikipedia)

There are four lesser known and less important signposts of the seasons, they are Beltane, Lughnasadh, Samhain and Imbolc. I’ve used the Gaelic names, but they correspond, in order, to the Christian festivals of May Day, Lammas, Halloween, and St Brigid’s Day. These all fall more or less halfway between the four main seasonal signposts.

Astronomically the Winter Solstice, which occurs around 21st December in the Northern Hemisphere. Many sources identify the date of the solstice as the beginning of winter. Similarly the Summer Solstice is identified as the start of summer, and the equinoxes are identified as the start of their respective seasons.

This is odd, as the climatic seasons are usually considered to start three weeks earlier, with Northern Hemisphere winter climatically starting around the 1st December, and similarly for the other seasons. Starting the astronomical seasons on the 21st (or sometimes 22nd) of the month misses out 3 weeks or nearly a quarter of the season!

It’s also odd for another reason. The Northern Hemisphere winter solstice is when the sun is at its lowest point in its apparent position in the sky, so it is at its turning point in the cycle of the season and indeed the word “solstice” means “the point where the sun stands still”. It seems to me that this should be considered the mid point of the season, not the beginning of it.

This is obviously true for the summer solstice too, and the equinoxes, being halfway between the solstices are add the mid points of the sun’s climb or descent to the solstices. They too also should be the mid points of their seasons, not the beginning points.

If the solstices and equinoxes are the middles of their seasons, where are the start end points then? Well, they would then coincide with the Gaelic or pagan festivals of Beltane, Lughnasadh, Samhain, and Imbolc! For example Beltane is about halfway between the Northern Hemisphere spring equinox and summer solstice on 1st May.

Although Beltane is a Gaelic or pagan festival and has mostly fallen out of favour, some cultures do celebrate the festival and some of the customs persist, such as the custom of dancing around a Maypole. Beltane and the other three similar festivals coincide with important agricultural events, such as sowing seeds and gathering in of harvests, so were of interest in earlier times.

However, if the astronomical seasons starts and ends were to be moved to coincide with the Gaelic festivals they would not coincide with the climatic seasons. The reason for this is that there is a seasonal shift because of the time that the seas and land take to warm up in spring and to cool down in winter. This pushes the climatic seasons back a few weeks and the start of climatic spring in the Northern Hemisphere is pushed back to about the 1st March and the same for all the other seasons.

That’s why I think that the current idea of the astronomical seasons starting at the solstices and equinoxes is wrong! They should coincide with the Gaelic festivals instead, and then the astronomical and climatic seasons are related by the seasonal shift, instead of not being related properly at all.

Illumination of the earth during various seasons (Photo credit: Wikipedia)

More on Quantum things

English: Schrödinger equation of quantum mecha... — English: Schrödinger equation of quantum mechanics (1927). (Photo credit: Wikipedia)

Schrodinger’s wave equation describes how the quantum state of a quantum system changes with time. Everett’s insight was that the observer of a quantum state was as much part of the system as the observed part of the system. Therefore they were “entangled” in the quantum sense and would be covered by a single quantum state equation.

If the observer and the observed are thus entangled, then so must be an observer who observes the quantum state of the observer and the observed. One can then extend this to the whole universe, which leads to the concept of a wave equation or function which describes the whole Universe.

That there is an equation for the universe is not really surprising and indeed, it is not surprising that it could be a quantum wave equation as the quantum world seems to form the basis of the physical, apparently classically described, world that we see.

I base this idea on the fact that everything that we sees appears to be describable in terms of a deterministic equation. It has been argued that such things as “psi phenomena“, but such claims are yet to be conclusively verified, with many putative examples having been discredited.



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Some people argue for a soul or mind as an example of a non-physical entity, but any such concept leaves a lot of questions to be asked. A non-physical entity cannot, by definition almost, be measured in any way, and there is difficulty in showing how such a non-physical entity can interact with physical ones, and therefore be noticed or detected.

By definition almost, a physical entity, such a body, is only influenced by physical things. If this were not the case we would see physical entities not following the laws of physics. For example, if it is possible to move an object by mind power or telekinesis, one would see the object disobeying fundamental scientific laws, like Newton’s First Law of Motion.

English: Isaac Newton Dansk: Sir Isaac Newton ... — English: Isaac Newton Dansk: Sir Isaac Newton Français : Newton (1642-1727) Bahasa Indonesia: Issac Newton saat berusia 46 tahun pada lukisan karya Godfrey Kneller tahun 1689 Lietuvių: Seras Izaokas Niutonas 1689-aisiais Македонски: Сер Исак Њутн на возраст од 46 години (1689) Nederlands: Newton geboren 4 januari 1643 Türkçe: Sir Isaac Newton. (ö. 20 Mart 1727) (Photo credit: Wikipedia)

The mind is a curious example of a physical entity which is often thought of as being non-physical. After all, a mind does not have a physical location, apart from the skull of the person whose mind it is, and it can’t be weighed as such.

The mind however is a pattern, on the brain, made up of the state of trillions of neurones. It is made up of information, and is much like a computer program which is made up of the state of a few billion physical logic circuits in the guts of the computer.

Open a computer and you won’t see “an image” anywhere. You will see patterns of bits of data in the memory, or on the hard disk, or maybe in transit, being sent to a computer screen. Similarly if you open someone’s skull you will not see an image there either. Just a bunch of neurones in particular states.

The one glaring exception to all the above, is, perhaps, consciousness. It’s hard to describe consciousness in terms of a pattern or patterns of the states of our neurones, but I believe that that is fundamentally what it is.

Some people argue that we are conscious beings, (true), and that we consciously make choices (false, in my opinion). When we look closely at any choice that we make, it appears to be that choice is in fact illusory, and that our actions are determined by prior factors.

People seem to realise this, although they don’t acknowledge it. When questioned, there is always some reason that they “choose” in a particular way. Perhaps they don’t have enough cash to choose the luxury option when out shopping, or their desire outweighs their financial state. When pushed people can always think of a reason.

To be sure, many “reasons” are actually post choice rationalisations, and choices may be based more on emotions than valid rational reasons, but whatever the emotions (such as the desire for an object), the emotions precede decision.

If, as sometimes happens, a person has to make a choice between two alternatives, that person can be almost paralysed with indecision. Even then, when a decision is finally made, it can be either a random choice, or maybe the person may say that they made a particular choice because they had decided a different way in another situation, or similar (e.g. they like the colour blue!).

If there is no non-physical component to the Universe, as appears very likely, and psi phenomenon do not exist, then everything has a cause. I don’t mean this in the sense that event A causes event B which causes C, but more in the sense that the slope that a marble is on causes it to move in a particular direction.

Causality seems to be a continuum thing, rather than the discrete A causes B case. We can only get an approximation of the discrete case if we exclude all other options. There is a latin term for this : ceteris paribus – all other things being kept the same. “Ceteris paribus” would exclude the case where a wind blowing up or across the slope changes the path of the marble.

For this reason I dislike the Many Worlds Interpretation of Quantum Physics, as it is usually stated. The usual metaphor is a splitting movie film, which results in two distinct tracks in the future. I feel that a better picture would be a marble on a slope with a saddle.

The marble may go left, or it may go right, or it may even follow the line of the saddle. We still require “ceteris paribus” to exclude crosswinds, but there is no split as such. In a quantum model, the marble goes both left and right (and traverses the peak of the saddle with vanishing probability).

The probability that it goes left or right is determined by the wave equation for the system, and has a real physical meaning, which it doesn’t (so far as my knowledge goes) in the splitting metaphor.

I don’t know how my speculations stack up against the realities of quantum mechanics, but I like my interpretation, purely on aesthetic grounds, even if it is far from the mark!



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Many worlds or only one?

English: Position and momentum of a particle p... — English: Position and momentum of a particle presented in the phase space. (Photo credit: Wikipedia)

Scientists often use the concept of a “phase space“, which is basically a representation of all the possible states that a system may be in. For the trajectory of a thrown stone for instance, the phase space would be a four-dimensional space, comprising the three dimensions of space, which define where the stone is, and one of time, which defines when the stone is in a particular position.

The trajectory of the stone is a line in this 4-d space, as the location and time information about the stone is known exactly. However, the stone is not a point and maybe be spinning at the same time that the whole object is flying through the air. This means that the trajectory would actually be a complex four-dimensional worm in phase space.

An animated GIF of a tesseract (Photo credit: Wikipedia)

What if we were to introduce a probability factor into the experiment? Maybe we would set up the projectile to be triggered by an atomic decay or something similar. We would get a different worm depending on how long the atom takes to decay.

Clearly, if we want to show the all of the possible versions of the worm, the worm now becomes a sort of 4 dimensional sheet. Well, more like a 4-d duvet really, as the stone is not a point object.

Bedding comforter or duvet. Français : Couette... — Bedding comforter or duvet. Français : Couette (literie). Deutsch: Daunendecke, umgangssprachlich Federbett. (Photo credit: Wikipedia)

Within the 4-d duvet, each worm represents a case where the atom has decayed, and each of these cases has a probability associated with it. The probability can be expressed as the probability that the atom has decayed by that time or not, and can run from one to zero.

Actually the probability starts from zero and approaches one but doesn’t quite reach it. In practise in a group of atoms some will decay quickly and others will take longer. If there are a finite number of them, then the chances of any one lasting a long, long time are quite small, and all of the atoms are likely to decay in a moderately short time, a few multiples of the half-life anyway. However there will be a finite but microscopic in the extreme possibility, that an atom will survive for as long as you may consider.



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We can add another dimension to the phase space, one of probability. This gives us a five dimensional phase space, and the duvet becomes five dimensional. However, an atom decays at a certain time, and there is a single five dimensional worm in the phase space going forward. The space is no longer a phase space though, as a phase space, by definition, describes all possible states of the rock/launcher/atomic trigger, and doesn’t change.

According to the Copenhagen interpretation of quantum physics the state of a quantum system is described by a set of probabilities. When a measurement of the system is made the state becomes certain, and it is said that the waveform described by the probability function has “collapsed”.

The famous thought experiment of Schrodinger’s Cat is a description of the difficulties of such a case. The cat is enclosed in a box equipped with a mechanism which will release a poison and kill the cat if triggered by the decay of an atom. At some time after the experiment starts the atom may or may not have decayed so the quantum states “decayed” and “not decayed” are superimposed, and therefore so are the states “dead” and “not dead” of the cat.

How do we know if the stone has been fired yet? Well, we go and look to see, and we either see the stone in its launcher or we don’t. Quantum physics says that the stone exists in a superposition of states – launcher and not launched. The question this raises is, if this is so, how does looking at the stone “collapse” the superposition when we look?

Three wavefunction solutions to the Time-Depen... — Three wavefunction solutions to the Time-Dependent Schrödinger equation for a harmonic oscillator. Left: The real part (blue) and imaginary part (red) of the wavefunction. Right: The probability of finding the particle at a certain position. The top two rows are the lowest two energy eigenstates, and the bottom is the superposition state \psi_N = (\psi_0+\psi_1)/\sqrt{2} , which is not an energy eigenstate. The right column illustrates why energy eigenstates are also called “stationary states”. (Photo credit: Wikipedia)

That quantum superposition is real is indicated by any number of experiments, even though many physicists working in the field (including Schrodinger himself) have expressed discomfort at the idea.

In quantum physics the evolution of everything is defined by the Universal Wave Function. This can be used to predict the future of any quantum physical system (and all physical systems are fundamentally quantum physical systems). Unfortunately for easy understanding, interpretation leads to the superposition problem mentioned above.



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Many people have tried to resolve this issue, and the best success has been achieved by the exponents of the Many Worlds Interpretation (MWI), as described by Everett and championed by Bryce DeWitt and David Deutsch. The view of the MWI exponents is that the Universal Wave Function is fundamental and expresses a true picture of all reality. All of it, that is. Not just a physical system and its observer.

Everett’s view, as described in his thesis, is that an observer, as well as the object that he is observing is a subsystem of the system described by the Universal Wave Function. The wave function of these two subsystems does not describe a single state for each of these subsystems, but the states of the two subsystems are superposed, or in Everett’s term, correlated.

en:Many-worlds interpretation (Photo credit: Wikipedia)

When a particle is observed it may appear to be in state A 70% of the time (correlated with a state A for the observer). Similarly it may appear to be in state B 30% of the time (correlated with a state B for the observer). This led Everett to postulate a ‘split’ of the universe into a state A and a state B. (The term ‘split’ appears to come from DeWitt’s interpretation of Everett’s work).

The probabilities don’t seem to have a function in this model, and this is odd. The probability that the cat is dead when you open the depends on how long you wait until you open the box. If you wait a long time the cat will more likely be dead than if you opened it earlier.

This means that the world splits when the cat is put in the box, as from any moment it can be alive or dead, but you do not find out which branch you are in until you open the box sometime later.

I’m ambivalent about the MWI. On the one hand it is a good explanation of what happens when a measurement is made or the cat’s box is opened, and it does away with the need for a waveform collapse, which Everett argued against in his paper. However it is profligate in terms of world creation.

Another issue is that the split is decidedly binary. The cat is alive in this world and dead in that one. However most other physical processes are, at the macro level anyway, continuous. When a scientist takes a measurement he writes down, for example, 2.5, but this is only inaccurate value as it is impossible to measure something exactly and it may be wrong by up to 0.05 on either side of 2.5 (given the one decimal point value shown).

Consequently, I’d prefer an interpretation where there is no split, but instead a continuum of possibilities as part of a single world. Maybe the single path that we tread through life is an illusion and across the Universe, by virtue of the Universal Wave Function, we experience all possibilities, though to us it feels like we are only experiencing the one.



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Religious matters

Seen on the signboard of a Christadelphian Church : “Seminar: Brexit and Bible Prophecy”. What?? Anyway, that started me thinking about religion again.

In the days that religion was developing as a means of understanding the world, when natural occurrences like storms and earthquakes were hypothesised to be caused by supernatural agencies, such as spirits and gods, the details didn’t matter too much to people.

If your neighbour believed an evil spirit caused a landslide, it didn’t matter too much if he thought that the spirit was male, while you categorised it as female, and your other neighbour didn’t assign the spirit a gender at all.

Eventually problems arose with this approach. When Johnny arrived home with a bloody nose because he had insisted that the spirit was female and Nigel next door had been told that it was male, issues arose. Nigel always was a bit of a bully, as was his dad.

The tribe as a whole would, over time, discuss the matter and come up with a consensus. The landslide djinn had to be female as it didn’t actually try to kill anyone, but made work for the men, who had to clear the slide from the track.

As time passed, the original idea of the evil spirit would become embedded in a mythos or body of myths, as the spirit’s role and actions are extended upon, firstly by grandparents telling kids scary stories to keep the kids awake at night, then embedded into the structure of the society as the adults, more or less jokingly at first, try to appease the wrathful spirits.

Eventually people starting taking the stories seriously. A whole structure of myths and stories got inflated into a cosmology and a rationale for the way things were. Johnny’s and Nigels’ descendants took all the stories and hypotheses and treated them as if that was the way things were, and to some extent they were correct.

Except that the daemon that started the rock slide was called gravity and it was not a active being with human characteristics but a force of nature, impassive and impartial.

Having experienced the scientific revolution, most societies on Earth these days recognise that earthquakes and landslides are not caused by malevolent supernatural beings, but by the forces of nature, but this has to be taught to kids.

As they grow up they believe in fairies and Father Christmas, but they soon learn to distinguish truth and fact. They may well believe in these beings for the benefit of adults and the possibility of presents and money for some time, but their belief in these beings is ambivalent. Eventually their belief is fake, and everyone knows that. It becomes a game.

Without any knowledge of science, our ancestors did the best that they could, and make the best guesses as to causes of phenomenon using the tools that they had at the time – myths and stories, based around being of unlimited power and dominion.

With the advent of writing, these myths and stories could be written down. The writings did not change, so the views of people were now tied to these fixed stories. A class of people arose who existed for the single purpose of understanding the writings and even interceding with the supernatural beings.

Some of the sages, magicians and priests would have been wise individuals who, fundamentally, did not believe the myths and stories in the writings, but who could see an opportunity, but the vast majority of the religious officials would have really believe the religious corpus.

When two culture came into contact there would have been a mismatch in the religious beliefs. Since the supernatural beings were, in general, born from disasters, such as floods and landslides, it would not do to offend them.

But the guy from the city over there believed that the seas came from the salt tears of the goddess, while you knew that the seas arose when the god split the rocks and the seas sprang from the depths of the earth.

What to do about this? Well, in most cases the traders or travellers would have no problem with this, most people being practical in nature, but when the priests heard, well all hell would break loose.

At the very least, some people would travel to other lands to try to persuade the inhabitants of their errors, and they would either succeed of fail. If they failed, they could be cast out or, possibly, put to death in various horrible ways.

If the missionaries were put to death, why then that would escalate things and war could be the end result. After all, yours was the one true religion and we can’t have heathens looping off the heads of true believers can we?

A group of believers (Photo credit: Wikipedia)

So we get religious wars, crusades and jihads. Remember, although we cannot really conceive it these days, religion was the only explanation people had of the world. Science would be along in a few centuries. In this rational and largely atheistic world that we live in, we can’t really understand the fundamental belief in religion that used to prevail.

We teach religion as a subject in schools, like maths or geography. It’s largely been dissociated from feelings and even belief. This is why in the Western nominally Christian world we are uneasy when people believe deeply in religion. It seems to us like a sort of throwback to more ignorant times.



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Religion is still strong in the rest of the world, though it does appear to be waning in influence. From our less religious point of view, the rabid followers of Islam seem insane and wrong, and it is hard for us to understand them at all. More moderate Muslims probably think that the so-called “radicals” are wrong, and are horrified by their actions, just as Westerners who are nominally Christian are horrified by the actions of the Klu Klux Klan or other extreme Christian cults.

Religions can and do exist side by side in many societies, but it is an odd situation. So long as people keep their views to themselves and practice their religion discreetly people get along. But if someone believes that their religion is the only true religion and that others are going to burn in hell or whatever, then that person would consider themselves to be justified in trying to save the others from themselves, by force if necessary. Or maybe that person believes that their deity requires them to force others to believe, and the same applies.



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Maybe this is not the end of the story. Science is an explanation of the world, observation based. It is possible, though unlikely in my view, that this world view is as misguided as religion is misguided. Maybe our descendants may look on science as we look on religion, as necessary, but ultimately wrong headed view of life.

Computer to Brain, Brain to Computer

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In the dawn of computing computers were essentially rooms full of racks and racks of circuits connected by mazes of cables. The circuits were formed out of electronic valves, relays, solenoids and other electronic and magnetic components, with not a single transistor to be seen, as semiconductors had not then been invented.

To reprogram such computers one often needed a soldering iron and an intensive knowledge of every part of the computer and how the parts interacted. From all accounts such machines were fickle, sometimes working sometimes not.

Since they were not housed in sterile environments or encased in a metal or plastic shell, foreign bodies could and did find their way into them and cause them to fail. Hence the concept of the computer bug. Computer pioneer Grace Hopper reported a real bug (actually a moth) in a computer and it made a great joke, but from the context of the report the term already existed.



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As we know computer technology rapidly improved, and computers rapidly shrank, became more reliable, and bugs mostly retreated to the software. I don’t know what the architecture of the early room fillers was, but the architecture of most computers these days, even tablets and phones, is based on a single architecture.

This architecture is based on buses, and there is often only one. A bus is like a data highway, and data is placed on this highway and read off it by various other computer circuits such as the CPU (of which more later). To ensure that data is placed on the bus when safe, every circuit in the computer references a single system clock.

The bus acts much like the pass in a restaurant. Orders are placed on it, and data is also placed on it, much like orders are placed through the pass and meals come the other way in a restaurant. Unlike the restaurant’s pass however, there is no clear distinction between orders and data and the bus doesn’t have two sides corresponding to the kitchen and the front of house in a restaurant.

Attached to the bus are the other computer components. As a minimum, there is a CPU, and there is memory. The CPU is the bit that performs the calculations, or the data moves, or whatever. It is important to realise that the CPU itself has no memory of what has been done, and what must be done in the future. It doesn’t know what data is to be worked on either.

All that stuff is held in the memory, data and program. Memory is mostly changeable, and can contain data and program. There is no distinction in memory between the two.

The CPU looks on the bus for what is to be done next. Suppose the instruction is to load data from the bus to a register. A register is a temporary storage area in the CPU. The CPU does this and then looks for the next instruction which might be to load more data from the bus to another register, and then it might get an instruction to add the two registers and place the result in a third register. Finally it gets told to place the results from the third register onto the bus.

I was not entirely correct when I said that there was only one bus in a computer. Other chips have interfaces on the main bus, but have interfaces on other buses too. An example would be the video chip, which has to interface to both the main bus and the display unit. Another example is the keyboard. A computer is not much use without input and output!

The architecture that I’ve described is incorporated in almost all devices that have some “intelligence”. Your washing machine almost certainly has it, and as I said above so do your tablets and phones. Your intelligent TV probably does, and even your stove/range may do. These days we are surrounded by this technology.

The above is pretty much accurate, though I may have glossed and elided some facts. Although the technology has advanced tremendously over the years, the underlying architecture is still based around the bus concept, with a single clock synchronizing operations.

Within the computer chips themselves, the clock is of prime importance as it ensures that data is in the right place at the right time. Internally a computer chip is a bit like a train set, in that strings of digits flow through the chip, passing through gates which merge and split the bits of the train to perform the calculations. All possible tracks within the chip have be traversable within a clock cycle.

Clockless chips may some day address the on-chip restrictions, though the article I cite was from 2001. I’m more interested in the off-chip restrictions, the ones that spring from the necessity to synchronise the use of the bus. This pretty much defines how computers work and limit their speed.

One possibility is to ditch the bus concept and replace it with a network concept little bits of computing power could be distributed throughout the computer and could either be signalled with the data and the instructions to process the data, or maybe the computing could be distributed to many computational units and the result could then be assessed and the majority taken as the “right” answer. The instructions could be dispensed with if the computational unit only does one task.

Network Computing Devices NCD-88k X terminal, back ports. (Photo credit: Wikipedia)

The computational units themselves could be ephemeral too, being formed and unformed as required. This would lead to the “program” and “computation” being distributed across the device as well as the data. Data would be ephemeral too, fading away over time, being reinforced if necessary by reading and writing, much like early computer memory was refresh on each cycle of the clock.

What would such a computer look like? Well, I’d imagine that it would look something like the mass of grey matter between your ears. Data would exist in the device as an echo, much like our memories do, and processing would be distributed through the device much like our brains seem to work. Like the brain it is likely that such a computing device would be grown, and likely some structures would be mostly dedicated to certain tasks, as in the brain.



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One big advantage that I see for such “devices” is that it should be very easy to interface them to the brain, as they would work on similar principles. It does mean though that we would be unlikely to be able to download one of these devices to a conventional computer, just as the contents of a brain could never be downloaded to a conventional computer.

On the other hand, the contents of a brain could conceivable be downloaded to a device like I have tried to describe.



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The Laws of Science and Magic

Everyone is familiar with the use of magic in stories, movies and video games. While it seems that it is possible for anything to happen in such environments, usually it is implicit that this is not so. It may even been touched on explicitly in the narrative.

What exactly is magic, though? Arthur C Clarke said that “Any sufficiently advanced technology is indistinguishable from magic” and that’s an excellent angle to approach magic from. An obvious example from the “magic is technology and technology is magic” approach is the introduction of guns to people who only knew spears and bows and arrows.

There are many laws of physics but the major ones comprise “classical physics”. I don’t propose to touch on quantum physics here – though magical devices might need to use such physics to account for the huge energy densities involved.

One of the cornerstones of classical physics is that you don’t get something for nothing. Energy is conserved and not created, though Einstein has shown that energy and mass are much the same thing.



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When Harry Potter waves his wand and his enemies are thrown backwards, the energy must come from somewhere, and that is from or through the wand. If the energy is stored in the wand, it would have to be stored very densely, and the densest form of energy is matter.

Does Harry’s wand transform mass to energy in a controlled way? Perhaps it does. Scientists talk about “cold fusion” and while it has not been demonstrated for real, perhaps it will be possible with future technologies.

Another possibility is that Harry’s wand is merely a channel for magical energies. Well, anything is possible, but I doubt it. The energies used in magic, for example, when used to repel attackers, are so large that the slightest inefficiencies in the process would probably melt the wand and destroy it and Harry with it.

Magic has been used to suspend people in the air, to overcome gravity. It usually requires the use of energy, so that the suspended person will eventually succumb to gravity eventually. Scientists have suspended small animals using magnetic fields, so it is definitely possible to achieve levitation with current scientific knowledge, this gives a hint about how magic might achieve the feat.

Daniel Dunglas Home, the famous Scots-born med... — Daniel Dunglas Home, the famous Scots-born medium of the nineteeth century, levitates himself in front of witnesses in the home of Ward Cheney in South Manchester, Connecticut on August 8, 1852. This illustration was first published in 1887 in the book Les Mystères de la science (The Mysteries of Science) by French psychical researcher Louis Figuier. (Photo credit: Wikipedia)

Wands are often controlled by voice. This again is not a huge step beyond current technologies. Our wands, I mean cell phones, can already be controlled by voice.

That actually brings up an interesting point. Wands are used for all sorts of things, to battle enemies, gain access to secure places, to travel in time, but they are rarely, if at all used for communications. Harry Potter does not talk into his wand to communicate with Ron Weasley and Hermione Granger, so maybe modern technology has something that is one up over magic.

When Harry throws a fireball from his wand, there is no recoil. This would appear to violate a number of physical laws. Energy appears to be created from nothing and the Law of Equal and Opposite Reaction (Newton’s Third Law) does not seem to apply.

The energy necessary to create the fireball can be attributed to a mass to energy conversion process as above. Such a process would, as described above, use very little mass to create the fireball and to send it towards Harry’s opponent. It’s possible that the reaction to the throwing of the fireball is absorbed by the wand or harmlessly directed in the opposite direction, much as the recoil of a “recoiless gun or rifle” absorbs or redirects any recoil.

Movie of a Fireball (Photo credit: Wikipedia)

Interestingly Harry’s opponents don’t usually appear to be seriously injured by his fireballs. They are thrown backwards and are usually discomforted by the fireball, but there is no sign of any wounds or other injury. Evidently they are cushioned in some way.

However several people were killed by the wands during battles, so it is evident that as weapon, the wands could be controlled by the users.



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Magic is able to transform things. Sometimes this is permanent, sometimes temporary. Sometimes people have the ability to change form, like the werewolves in many stories. Science does not have the ability to do things like this, but it occurs in nature, when a caterpillar metamorphoses into a butterfly.

Maybe science will be able to perform such feats, when we have mastered the genetic code. The body shows remarkable abilities to recover from trauma, to repair itself. Maybe we will some day learn how to use these abilities to modify our bodies in a similar way to the way that magic does.

It is unlikely that we will achieve the instant transformations of magic in the near future, but we may be able to regrow damaged arms, to change our heights and bodily appearance. For most people the first priority will be to gain the ability to control obesity!

Invisibility is a theme of magic. The hero uses the ability to become invisible to sneak past the guards and to rescue the maiden, recover the lost valuable, or defeat the evil overlord. Science has been trying to perform this trick for a long time, and has achieved some success. At the very least you can use an “Invisible Fence” to contain your pets!

Beyond the Invisible (Photo credit: Wikipedia)

Things can be made invisible by the use of mirrors, but that’s not quite the same as an Invisibility Cloak. Things can be made invisible by camouflage too, though that again can be considered as cheating, I suppose. Real invisibility, which amounts to complete transparency, is currently unachievable by science. I would not bet against science being able to bend light around objects to make them properly invisible in the long term though.

A disadvantage to becoming invisible, apart from people tending to walk into you of course, is that you would not be able to see where you are going without disrupting the very fact of your invisibility. This is because you need to capture photons to be able to see. You may not need a lot of photons, but it would mean that there would be a slightly dim patch where you are standing with your Invisibility Cloak and you would not be able to see what is around you.



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Arthur C Clarke’s dictum implies that everything achievable by magic would eventually be achievable by science. It may be that some things achievable by magic in stories are actually physically impossible, so we will never be able to achieve them. But it is interesting to think of ways that they might be achieved by science.

2001's Discovery miniature — 2001’s Discovery miniature (Photo credit: Wikipedia)

Is the Brain a Computer?

I’ve just read an interesting article by Robert Epstein which tries to debunk the idea that the brain is a computer. His main thrust seems to be that the idea that the brain is a computer is just a metaphor, which it is. Metaphors however are extremely useful devices that use similarities between different systems to perhaps understand the least understood of the two systems.

Epstein points out that we have used several metaphors to try to understand the mind and the brain, depending on the current state of human knowledge (such as the hydraulic metaphor). This is true, but each metaphor is more accurate than the last. The computer model may well be the most accurate yet.

The computer model may well be all that we need to use to explain the operation of the brain and mind with very high accuracy. Brain and mind research may eventually inform the computer or information technology.

It is evident that Epstein bases his exposition on a partially understood model of computing – for instance it appears that he thinks that data is stored in a more or less permanent fashion in a computer. He says:

The idea, advanced by several scientists, that specific memories are somehow stored in individual neurons is preposterous; if anything, that assertion just pushes the problem of memory to an even more challenging level: how and where, after all, is the memory stored in the cell?

This describes one particular method of storing data only. It sort of equates with the way that data is stored on a hard disk. On a disk, a magnetic bit of the disk is flipped into a particular configuration which is permanent. However, in the memory of a computer, the RAM, the data is not permanent and will disappear when the computer is switched off. In fact the data has to be refreshed on every cycle of the computer’s timer. RAM is therefore called volatile memory.

In the early days of computing, data was stored in “delay line memory“. This is a type of memory which needs to be refreshed to preserve information contained in it. Essentially data is fed in and read out of a pipeline simultaneously, the read out being fed back to input again to complete the cycle and maintain the memory.

I expect that something similar may be happening in the brain when remembering something. It does mean that a memory may well be distributed throughout the brain at any one time. There is evidence that memory fades over time, and this could be related to an imperfect refresh process.

Epstein also has issues with the imperfect recall that we have of real life objects (and presumably events). He cites the recall of a dollar bill as an example. The version of the bill that people drew from memory was very simplified as compared to the version that they merely copied.

All that this really demonstrates is that when we remember things a lot of the information about the object is not stored and is lost. Similarly, when an image of the dollar bill is stored in a computer, information is lost. When it is restored to a computer screen it is not exactly the same as thing that is imaged. It is not the same as the image as stored in the computer.

It’s worth noting the image file in a computer is not the same as the real thing that it is an image of, as it is just a digitisation of the real thing as captured by the camera that created the image.

The image on the screen is not the same as either the original or the image in the computer, but the same is true of the image that the mind sees. It is digitised by the eye’s rods and cones and converted to an image in the brain.

English: Stylized idea of the communication be... — English: Stylized idea of the communication between the eye and the brain. (Photo credit: Wikipedia)

This digitised copy is what is recalled to the mind’s eye when we remember of recall it. The remembered copy of the original is therefore an interpretation of a digitised version of the original and therefore has lost information.

Just as the memory in our minds is imperfect, so is the image in the computer. Firstly the image in the computer is digital. The original object is continuous. Secondly, the resolution of the computer image has a certain resolution, say 1024 x 768, and some details in the original object will inevitably be lost. More details are lost with a lower resolution.

In addition the resolution of the image stored in the computer may not match the capabilities of the screen on which it is displayed and may need to be interpolated which produces another error. In the example of the dollar bill, the “resolution” in the mind is remarkably small and the “interpolation” onto the whiteboard is very imperfect.

Epstein also assumes a particular architecture of a computer which may be superseded quite soon in the future. In particular in a computer there is one timing circuit, a clock, that all other parts of the computer rely on. It is so important that the speed of a computer is related to the speed of this clock.

It may be that the brain may operate more like a network, where each part of the network keeps its own time and synchronisation is performed by a message based scheme. Or the parts of the brain may cooperate by some means that we don’t currently understand. I’m sure that the parts of the brain do cooperate and that we will eventually discover how it does it.

Epstein points out that babies appear to come with built in abilities to do such things as recognise faces, to have certain reflexes and so on. He doesn’t appear to know that computers also have built in certain basic abilities without which they would be useless hunks of silicon and metal.

When you switch on a computer all it can do is read a disk and write data to RAM memory. That is all. When it has done this is gives control to program in RAM which, as a second stage, loads more information from the disk.

It may at this stage seek more information from the world around it by writing to the screen using a program loaded in the second stage and reading input from the keyboard or mouse, again using a program loaded in the second stage. Finally it gives control to the user via the programs loaded in the second stage. This process is called “bootstrapping” and relies on the simple hard coded abilities of the computer.

But humans learn and computers don’t. Isn’t that right? No, not exactly. A human brain learns by changing itself depending on what happens in the world outside itself. So do computers!

Say we have a bug in a computer program. This information is fed to the outside world and eventually the bug gets fixed and is manually or automatically downloaded and installed and the computer “learns” to avoid the bug.

Learning Organism (Photo credit: Wikipedia)

It may be possible in the future for malfunction computer programs to update themselves automatically if made aware of the issue by the user just as a baby learns that poking Mum in the eye is an error, as Mum says “Ouch!” and backs off a little.

All in all, I believe that the computer analogy is a very good one and there is no good reason to toss it aside, especially if, as in Epstein’s article, there appears to be no concrete suggestion for a replacement for it. On the contrary, as knowledge of the brain grows, I will expect us to find more and more ways in which the brain resembles a computer and that possibly as a result, computers will become more and more like brains.

Inspiration

In Terry Pratchett’s series of Discworld books, one of the characters, Hwel, a dwarf, is a playwright, and writes plays which are obvious references to Shakespeare’s plays. Indeed some of the books themselves have themes based around Shakespeare’s plays.

Hwel is tormented by inspiration. He is a dwarf, and therefore by heredity a dour reclusive and unimaginative entity, but because of his mind is full of myriads of ideas, he is compelled to travel among humans and write his plays.

The witches (Jennifer Hunt, Suzanne Curtis, an... — The witches (Jennifer Hunt, Suzanne Curtis, and Sonja Lanzener) surround Macbeth (Remi Sandri) in this 2004 Alabama Shakespeare Festival production of the Shakespear masterpiece. (Photo credit: Wikipedia)

These ideas sleet through the Discworld universe impinging on and inflaming his dwarf brain. Hwel is also tormented by vivid dreams, which he then struggles to put down on paper. He is always dissatisfied with the result and is constantly revising and rewriting his plays.

Hwel is an excellent example of an inspired individual. His character is obviously a reference to Shakespeare, and many of his traits, such as his dissatisfaction with his inability to capture his ideas and concepts on paper, are traits found in many inspired individuals.



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Pratchett leaves the question of the source inspiration open. As above, they sleet through the Discworld universe impinging on the brains of all, especially those like Hwel, like neutrinos sleet through the material universe, only rarely interacting with other matter.

Everyone has ideas. Inspiration is a sort of high grade idea that has the wow factor and it is likely that simple ideas and inspiration have the same source. It is also obvious that ideas and inspiration actually spring from inside us, from inside our minds.

Inspiration (sculpture) (Photo credit: Wikipedia)

There is probably not a particular part of the brain where ideas arise and inspiration is found, though some brain injuries result in people being unable to act voluntarily, these people however responding to instruction. (Caveat emptor: I’ve not been able to find an example of this on Google)

Inspiration seems to happen more frequently when a person is forced or required to look at a problem or issue from a different point of view, or when novel ideas are considered in conjunction with one another.

As I sit here, wondering what I should type next, I am looking for inspiration to come to me. In my mind I consider a number of possibilities, which run through my mind one after another, quite quickly. Some seem to be more attractive than others and the rejects seem to fade or drop back into the background.

So, it turns out that I decided to write about what goes on in my head when I get an idea. I can only assume that similar happens to others when the undertake a similar activity like writing a blog, or a novel, or even a letter to a friend.

Often, I find, one idea leads clearly and obviously to another. I write one sentence and soon find I’ve written a paragraph or two, and then I pause for thought and the process repeats. Eventually I end up with the full completed letter or blog post or whatever.

Inspiration is thinking outside the box. Terry Pratchett once said “I’ll be more enthusiastic about encouraging thinking outside the box when there’s evidence of any thinking going on inside it”. That’s true indeed, but the point of the “thinking outside the box” idea is to encourage people to discard conventional thinking and think in an unconventional manner. That’s easier said than done.

One way is to take conventional thinking and analyse it into facets or factors, and discard or reverse one of them. In a scientific but probabilistic setting, such as that of Schroedinger’s cat thought experiment, conventional thinking is that the cat must be either alive or dead. Thinking outside the box leads many people to consider that the cat is both alive and dead.

Some people seem to have success in deriving inspiration from a mind map or even a list of words. Some people have been known to use drugs or meditation to aid inspiration. It seems that the human mind is conservative and conventional in the most part, and that inspiration, when it doesn’t come freely, can be aided by persuading it to be more adventurous.

Meditation and mind maps or whatever tool is used to free the mind for inspirational thinking may be necessary in some cases, but in many others inspiration comes without the need for such things. Some people, like the dwarf Hwel above can’t help being inspired and this, as in Hwel’s case, is not necessarily a comfortable feeling.

Inspiration come in small chunks, such as the decision to drop all plans and do something different from usual or huge blocks, such as Hwel’s and Shakespeare’s plays. As I said above, it does some to vary from person to person, and possibly from time to time. For instance, if I’ve done the same thing 20 to 30 times recently, I may be inspired to do something different, for a change.

weather symbol (Photo credit: Wikipedia)

If you search on Google for “inspirational” you will find that many of the search results are for “inspirational quotes”. Most of these are in fact trite homilies, intended to list the spirits of those who need it, exhortations to remember and to treat friends and families well, and similar.

They are not inspirational in the sense that I have been using the word above. Nevertheless, the sheer number of such quotes appears to indicate that some people feel the need to post them in the hope that they will help others. Whether or not they actually help others is something that it would be hard to gauge. I sometimes wonder if only the people creating and posting these posts get any benefit from them.



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Some people are inspirational in that they persuade people to do things that they would otherwise not do. This could be good (Mahatma Gandhi) or bad (Adolf Hitler). A truly inspirational leader can change the world.

Inspirational leaders can be bad because their rhetoric and behaviours can override the sensibilities and consciences of their followers, which is particularly true of Hitler. Even the followers of good leaders can do evil at times, instituting pograms and wars against followers of other religions.

Thinking Inside of the Box

Science aims to explain things, and by extension to explain everything. Is this even possible? Suppose the Universe consisted of a box, 20 million metres in each direction. Scientists inside this box could investigate this universe, but could they explain everything about this universal Box?

Suppose that the Box had impenetrable walls, so scientists could not probe outside of it. So they could say that the width, height, depth of the universe was 20 million metres and they could describe what was in it. They could also say that one side of the cube attracted everything in the Box and that side could be labelled “down” and the opposite side “up”.

English: Snapshot from a simulation of large s... — English: Snapshot from a simulation of large scale structure formation in a ΛCDM universe. The size of the box is (50 h -1 Mpc) 3 . Run using GADGET (GPL software) (Photo credit: Wikipedia)

There also might be statistical laws, so that the temperature, on average, might be 20 degrees Celsius, but could differ from that norm from place to place and from time to time. Box scientists might determine that everything appeared to be made up of tiny indivisible particles. Box atoms.

Some Box philosophers might ponder what was beyond the limits of the Box. They’d ponder the fact that starting from one side of the Box, one could travel 20 million metres in a perpendicular direction, but one could not travel 20 million and one metres. Why not?



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I’m sure that they would have plenty of theories. For instance, one philosopher might contend that the Box was embedded in an infinite impenetrable bedrock, while another might say that it was obvious – the Box was embedded in nothing. No space, no time, no thing!

Meanwhile scientists probing the Box atoms might split them and discover a whole new world of sub-atomic particles. Others might conceive of space in the Box as being a seething mass of pairs of virtual particles, being created and moving apart for a brief instant and then merging into nothing, no thing, again.

But, says one bright spark, what about a particle pair created on the boundary of the Box? One particle would enter the Box, and the other would travel somewhere else! This would lead to other speculation – if the second particle travelled in another Box, then that other Box would presumably be a mirror image of our Box!

Such speculation would wait on experimentation by the Box scientists and I’m aware that I cannot push the Box analogy too far with out it breaking. But, just as in the case of the Box scientists, philosophers and scientists in this Universe have similar issue.

An illustration of a ramified analogy, one com... — An illustration of a ramified analogy, one component of Gordon Pask’s Conversation Theory. Self-made (Photo credit: Wikipedia)

In our Universe there are no bounds (under current theories, I believe) but that doesn’t mean that we can’t speculate about what is beyond our Universe, whatever “beyond” may mean in this context.

The Box scientists could potentially explain every thing in the Box, maybe even the fact that it had existed, pretty much unchanged (on average) for all time, and that is periodically, over astronomically long time scale is doomed to repeat itself, time and time again.

When they go further than that, it is pure speculation, as all the data that they have relates to the Box. They have no data from outside of the Box. All the waves and particles that are observed originate in the Box. All the forces and fields are part of the Box. While scientists may speculate about “other Boxes”, that is all that they can do.

That’s the problem. The Box scientists, and the scientists from our Universe, can only observe events in the Universe in which they are embedded. Observations relate only to events in the local Universe.

Some conjectures suggest that our Universe is one of many universes all linked together in some way. Some conjectures suggest that the laws of our Universe apply in many other similar universes separate from ours. Some people conjecture that universes may exist where there are no laws or the laws that there are have no similarity in any way to the laws of our Universe.

In the Box universe these conjecture would amount to ideas that there may be other Box universes out there with similar laws to the Box universe, maybe linked in some way to the hypothetical Box universe. There may even be universes which have laws which are not at all similar to those of the Box universe. For instance a universe which springs from a single point in a vast explosion and expands at a vast rate either forever or to a certain point only to collapse once again. How bizarre!

The Box scientists would not have any way to decide whether or not their were any other Boxes as their observations would only observe events in their own Box. The only way that events in one Box could possibly affect the events in another Box would be if there was a link between them in some way.

This doesn’t necessarily mean that the event would be observable as the effect of one universe on the other universe. It would just appear as an event in each universe as it transpires as a result of the laws of the universe in question.



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The theory may posit a link between two universes but the events in one universe can only result from events within that universe. If this were not so, the event in the universe would appear to happen without any causation in the universe. In other words it would be an anomaly or a miracle.

In other words, suppose a scientist in one universe knows of a law where he can cause an effect in another universe. If he can cause this effect in his universe then in the other universe something will also appear to cause this effect. Maybe this cause will be a scientist in the other universe trying to create an effect in the first universe!



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This possible symmetry of cause and effect across more than one universe would mean that it would be difficult if not impossible to detect the presence of another universe by its effects on our universe.

The person in the Box universe would likely be in the same position. This means that he would never know if there were anything outside of his 20 million metre cube. He could postulate an infinite series of Boxes stacked like bricks in an endless array. Or he could postulate Boxes grouped into “houses”. Or he could postulate that his was the only Box and that speculations about universes started from “Big Bang” explosions are mere fiction.

Feedback

A Kahn process network of three processes with... — A Kahn process network of three processes without feedback communication. Edges A, B and C are communication channels. One of the processes is named process P. (Photo credit: Wikipedia)

When an output of a process is taken and fed back to the input of a process it causes changes to the output. This changed output is then fed back to the input and so on. This basic idea has myriads of applications, in nature, in science, and in real life.

Feedback can be positive or negative. If it is positive, it adds to the input, which increases the output, which is then fed back to the input, which increases it still more, and we have a runaway increase. This is what causes the howl that occurs when the output from a microphone amplifier is accidentally fed back to the microphone.

Negative feedback subtracts from the input, which can result in a reduction of the output of the process. It won’t necessarily result in NO output however, as the amount of feedback is reduced as a result of the output being reduced, and therefore the output may drop to a fixed value. There are relatively complex equations which govern feedback behaviour which I’m not going to go into here.

Of course the input and output must be related for feedback to be possible. Electrical circuits are a classic example, of course where the input and output are both voltages, and in the case of a cruise control system, the speed of the car is converted to a signal (which may be a voltage, I’d guess) and the feedback is via a signal applied to the fuel control system, which again could be a voltage.

Feedback is inevitably delayed with respect to the inputs. In any real system the input takes time to be fed back, and sometimes this interferes with the intended operation of the feedback loop. It can cause swings in the size of the output, and the system state oscillates.

This is how electronic oscillators are designed to work, but in control systems such oscillations are unwanted and could be destructive. One way to deal with this is to “damp” the circuit, which effectively slows the feedback so that the system state moves more slowly towards the desired state rather than attempting to jump directly to it. Such damping helps reduces overshoot where the momentum of the raw feedback would cause the output to go past the required value.



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The input and output together with the feedback form a feedback loop. Feedback loops can be found everywhere, in mechanical and electrical systems, in climate systems and biological systems.

One interesting question is whether or not there is a long term feedback loop that will react to global warming to reduce the effects after a while. If so, would the feedback be more detrimental to the human race than global warming itself.



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Such feedback could be something like increased storms and disappearance of seasonal rain that will eventually finish off the human race, perhaps. According to the Gaia hypothesis the Earth is a dynamical system that help to maintain life on Earth. If that is true, it may be broken by global warming, or it may react against global warming in ways which may not yet be apparent.

Systems may have more complex feedback going on than a single simple positive/negative. A process may have several independent positive and negative feedback loops operating at the same time. The various loops may be connected in complex ways and the behaviour may be impossible to accurately predict.

A biological example is the case of the rabbits and the foxes. The population of the rabbits depends on many things – how many bunnies there are, the extent of their food supply, the maturity of the average bunny – how many are mature enough to be able to produce more bunnies. Similarly such factors apply to Basil Brush and his cohorts.

If the rabbits food is plentiful, then they will breed, well, like rabbits and the population will rise. This provides an increased food supply for the foxes and their population increases. Eventually the rabbits manage to increase to the stage where the food becomes limited and the population stops increasing.

Alternatively the increase in the fox population may grow faster than the rabbit population. The foxes kill more rabbits than the rabbits can replace and the rabbit population crashes. The foxes then starve to death as the rabbits start to recover. There are various opinions as to the exact mechanism is concerned, but there is no doubt that boom and bust cycles are seen in the predator/prey relationship, and there is no doubt that feedback cycles are involved somehow.

It is often said that negative feedback acts to return the system to equilibrium. While this may be true in the short term, any such equilibrium is temporary, and as the rabbits and foxes example shows, it is more likely that a system will only temporarily return to the equilibrium and often a system will pass through equilibrium many times as it oscillates too and fro.



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In fact, in most cases the “equilibrium position” will rarely be occupied by the system for any length of time. The typical system that oscillates about an “equilibrium position” is a pendulum. A pendulum is travelling its fastest when it passes the lowest point of its arc. The “feedback” in this case is provided by gravity of course.

Feedback also describes the missives and reports sent to an organisation about its services. The organisation may have sought such feedback by distributing questionnaires, by links on a web site, or maybe by word of mouth. Respondents have the opportunity to provide both positive and negative feedback depending on their experience with the organisation.

English: Overview of four different options to... — English: Overview of four different options to be A/B tested for Wikimedia’s Article Feedback Tool V5. This A/B test would let us compare these different options for an improved feedback form, to find out which version is most effective for engaging readers and improving article quality. See project page (Photo credit: Wikipedia)

Such research and feedback is called “market research” and has seen organisations change their stance on some topics. McDonald’s Corporation has banned plastic food containers (in 1990) and plastic drink containers (in 2013) as a result of feedback from environmental lobby groups.

Politicians also get feedback from the voters in the form of opinion polls and surveys. It would be a brave politician (perhaps a soon to be former politician) who ignores the opinion polls. Such a politician would be looking for a fresh job after the next election.

(I believe that I am now all caught up on the posts that I missed. Yeah!)