Physics: The measurement illusion

Physics relies heavily on measuring some aspect or behavior of whatever is studied.   But the accuracy and authenticity of the process are more dubious than commonly recognized – with consequences for the trustworthiness of both physics and everyday ideas.

Although not a direct question in physics, the means by which we identify entities, aspects, phenomena and qualities of our reality is a contentious matter within cognitive psychology and philosophy, with implications for theory and reasoning within physics.   The simple act of measuring anything at all raises questions about the reliability of popular approaches to understanding the physical world.   Measurement, as opposed to simple counting, appears to be nothing more than comparing two things within a situation where there is actually no ultimate scale for anything.

When we place a ruler or other measuring device against an object to measure its length, we have to accept that temperature, humidity and other physical variables can change the size of both the object and our measuring device, and it is unlikely both objects will be affected to exactly the same degree.   So the idea either of the two things has some real and permanent size actually makes no sense.   Instead we ought to see stated measurements as only ephemeral approximations, and observe how what we think of as the size of anything is actually subject to constant change.   There will also be some inaccuracy as a result of limited precision inherent to every measuring process.

These same issues apply everywhere: there is no way of stating a single enduring and exact measure of anything.   In simple terms, it appears that nothing at all remains constant under the changing physical conditions of our universe, and that what we think of as exactitude therefore eludes us at every turn.

The approach of physics to this has understandably been to design measuring tools that remain as unaffected as possible amidst changing physical conditions.   For example, a ruler made from a metal more or less stable under temperature changes is obviously preferable to one using a metal that changes size significantly with temperature variations.

Nonetheless, the idea that comparing two things is somehow about measuring one item according to the other remains suspect when everything including the measuring tool is subject to change.   Therefore, such measuring processes are better understood as just relating one thing to another – not about some properly objective measurement of either.   This forms an everyday explanation of what physics at great pains derived as the theory of relativity – at least inasmuch as observations depend upon the conditions under which those observations are made.

As an illustration of this, nothing is achieved by stating that water freezes at 0º C (Celsius) and boils at 100º C, without some means of specifying the Celsius scale of temperature.   This example is particularly easy as these two points on the Celsius scale are loosely defined as the temperatures at which these physical changes in water occur.   However, that definition assumes the state of certain other variables which affect how water behaves.   In any case, the situation seems rather circular in that water is deemed to boil at 100º C, and 100º C is deemed to be the temperature at which water boils.   The same can of course be stated for water freezing at 0º C.

But as it turns out, even this closed loop logical circularity cannot settle matters as far as conventional physics is concerned – precisely because, just as mentioned, other variables can alter measurements.   From a philosophical point of view the matter could be settled by simply stating that water freezes at 0º C and boils at 100º C, and leaving matters there.   However, physics considers this too casual an approach when the temperature of these transitions is known to vary according to other factors.   The philosopher is nonetheless entitled to argue back that that is exactly why he goes no further – the idea of temperature as something in its own right and independent of other variables being just an assumption on the part of the physicist.   Isn’t all the evidence suggesting that this elusive temperature is in fact something that cannot be isolated in the manner the physicist seeks?

For better or worse, traditional physics has always sought to rule out variability and to derive utterly consistent measures of the world it examines.   Therefore, when it notices for example how atmospheric pressure appears to affect the temperatures at which water freezes and boils, it tries to deal with this by including pressure within its definition of the Celsius scale.   But this strategy reveals itself as an ad infinitum process in terms of nailing anything at all in an absolute manner.   The problem in this example concerns how atmospheric pressure could be measured without further questions being asked about whatever measuring devices are used for that parameter.   Again, we are forced to accept the ultimate absence of any way of measuring anything absolutely.

It seems inescapably true that all popular measurement techniques remain based on comparisons of one thing with another – all within a world where everything exists in constantly changing conditions.   Therefore, all measurement appears inherently relative to other parameters.

Strictly speaking, the idea anything truly has a real and knowable temperature appears misguided given any measurement of temperature is subject to the conditions under which temperature is measured – those conditions affecting both whatever is measured and all measuring devices.   Nothing is completely stable, and all attempts to stabilize conditions just rely on additional more or less unreliable measurements.

Physics has worked hard to minimize this problem in many domains, but the interesting observation from a philosophical perspective is that the problem ultimately appears intractable.   The search within physics for exact measurements struggles against two hard facts; reality is in a state of flux, and phenomena cannot be isolated from surrounding environmental influences.   Thus, although the absolutist thinking of physics can prove practical, it appears philosophically wrong-footed – something even reflected in the common use of paradoxical language such as a state of flux.

Reducing the effect of unwanted variables is a key concern in the design of all sorts of measuring equipment and processes – all based on the assumption pure essences such as temperature actually exist, and that problems measuring them absolutely are just by-products of measuring techniques.

However, the apparent impossibility of measuring anything at all absolutely can be seen as hard evidence the idea of anything at all existing in isolation is flawed – the implication being there is no such thing as an absolute temperature, or at least if there is such a thing, it is not something we can access.

And none of this is even to scratch the surface of a much bigger problem – namely that the idea of an exact temperature of anything tacitly assumes a uniform temperature throughout the entirety of that thing.   But even by conventional science it would seem reasonable to assume that the different atoms or molecules that make up whatever we consider would have subtly different temperatures.   In fact, such differences are the very basis of conventional ideas of heat exchange.

There are major ramifications with debunking the subliminal but culturally all-pervasive notion that things, entities, phenomena and so forth should be understood as isolated elements within reality.   But even the alternative proposition that nothing at all can be properly understood without considering its context does not fully address the issue.   From a philosophical perspective, the question becomes one about the validity and authenticity of abstract thought itself – specifically as regards its object-based model of reality.   It is questionable whether the cognitive act of thinking about any thing at all is not in fact a divisive distortion inasmuch as conceptualization of such things presumes a discontinuous aspect of reality that perhaps does not exist outside the mind.

Conventional physics plus its procedures and discoveries obviously underpin many pragmatic goals, whilst philosophical speculation about human cognition or temperature-measuring techniques hardly nullifies the everyday usefulness of devices such as thermometers.   However, if philosophy seeks to push the frontiers of human thinking, it should not limit itself to whatever proves merely useful.   In terms of understanding as fully as possible the reality in which we find ourselves, it ought to challenge our common ideas and assumptions, and question to what extent they are artifacts of the mind’s functioning – as opposed to being directly representative of reality.

As discussed, evidence arising from efforts to quantify and calibrate our reality suggests ideas such as true temperature are of a hypothetical nature rather than being anything ever substantiated – even if physics has a long history of assuming otherwise.   If anything has such a true quality it nonetheless remains impossible to establish and must therefore remain conjecture.   Perhaps the fact we cannot get beyond such conjecture is indicative of a misguided perspective – or at least that limits should be recognized as regards how far to trust that perspective.

Our ideas of measuring time reveal issues similar to those with temperature, but in a more general manner.   The very idea that we either understand time, or are in a position to measure it, appear based on yet more assumptions, conventions and cognitive conveniences – as opposed to reliable proofs.   Everyday use of the concept of time is one thing, but the physicist’s idea that it is a properly quantifiable entity is easily undermined.

As with temperature, attempts to deal with the challenges of accurately measuring time have tacitly concluded that measured time is ultimately subject to conditions in which such measurements are made.   In physics, the theory of relativity in particular has focused on this in a manner counterintuitive to ordinary thinking, given that it infers time is more or less elastic.   According to relativity, time can be distorted by velocity and gravity, and this effectively nullifies the everyday idea that time is universal.   But it also raises a question about what time itself might really be – and if we are even in a position to understand such a question.   Although we can obviously define any supposed thing inasmuch as we concoct some verbal description of, in this case time, does that description translate into any phenomenon that is unambiguous in terms of our experience of the physical world?

The atomic clock is considered one of the most accurate devices for measuring whatever time is thought to be – it being commonly used in physics experiments for that very reason.   Experiments using such clocks are considered to measure time accurately to minute fractions of a second.   However, there is a philosophical question about whether the observations of such devices reflect some real entity that is time, or just the behavior of the device.

The general consensus within physics is that the tiny changes observed when for example, an atomic clock’s position is altered vertically to alter the strength of Earth’s gravity, reflect tiny changes in the rate time passes.   The thinking is that the clock performs authentically and truly records different rates at which time passes under different gravitational conditions.

But things do not look so obvious if we consider this idea alongside the fact that a basic mechanical clock may run fast – as we would typically envisage matters – when it is over-wound.   In this second example conventional thinking considers that changing the running conditions of the clock cause a problem with the clock, but leave the rate that time passes unchanged.   So why should we consider that changing the running conditions for the atomic clock is any different?   In moving the atomic clock to conditions of altered gravity, have we not just altered the running conditions such that the clock operates at a different speed?   The problem here arguably lies in the assumption that time is something other than just our preferred ideas of it.

As organic beings we have an inbuilt awareness of continual change, and we seem able to gage real-world change through the organism.   We have a rough idea whether something happened one, two or three hours ago – even if that awareness seems far less accurate than a manufactured clock.

In any case, the human mind can be considered to have invented time as a concept to monitor worldly processes in a coordinated manner.   Clocks were designed as devices to measure changes in reality, and to generally structure civilization around natural events.   Of course, the role played by natural occurrences such as day and night has increasingly diminished as hours, minutes, seconds and even milliseconds have become common currency.   The supposed entity thus counted is in any case called time.

But once we allow for observed and continual change, is there anything more to time than the convenience of the idea?   We can talk about hours, months and years in terms of memories or plans, but we cannot explain what such things are beyond lengths of time as defined by our measuring techniques and abstract ideas.   And as we cannot access such supposed things in any way with our sensory apparatus, it is somewhat curious that we believe in them at all.

In pondering whether changing the running conditions of an atomic clock causes a change in the rate at which time passes or a change in the running of the clock, we seem to mistakenly assume these are two different things.   Importantly, the assumption that physics makes is that the rate at which time passes according to the atomic clock reflects a more or less global rate of time passing under those given conditions or frame of reference: unlike the over-wound mechanical clock, the readings of time are not considered to result from some aberration of the clock itself.

But the fact that someone who was not very attentive or aware of their day passing could easily believe the wrong time on the over-wound clock was the right time, illustrates how measurements and supposed points in time are effectively just whatever we believe or agree them to be.   The whole system of seconds, minutes, hours, weeks, days and so forth is just human invention – albeit apparently based roughly on a few fairly stable aspects of our planet and its moon’s movements.   The so-called right time remains purely based on agreed conventions.

It appears that the supposed measurement of time is just another comparison between two things – typically some sort of clock, and some progression or sequence of events.   Time itself, if such a thing exists, is not directly accessible – just as temperature appears ultimately too obscure to establish.

The common idea of time as immeasurable can in fact be applied to any parameter at all in the sense that we can never get beyond comparisons to make what we idealize as absolute measurements.   The measuring device utterly immune to external influence has not yet been found or devised, despite very extensive efforts to do so.

Moreover, within the current thinking of physics, it seems impossible such a thing could exist unless prevailing conditions were shown to be utterly identical and static.   But how could it ever be shown that different instances of measurement took place under identical conditions, given our measuring devices are known to be subject to variation in the first place?   In any case, even identical measurements do not necessarily indicate wholly identical conditions – two or more altered variables being able to cancel each other out.   How could we even identify truly static conditions amidst a universe of continual change?   Bodies that produce gravity are in continual motion, and gravity is considered to have an infinite reach – a situation that logically renders the idea of static conditions as simply impossible.

The goal of this discussion is not to simply highlight the finer points arising from attempts to make exacting measurements; it is to examine the philosophical implications of the hitherto scientific failure to fully isolate any entity at all within nature.   We have some very basic concepts such as mass, energy and time, and yet we cannot quantify any of these without other variables having an influence.   This indicates how even what we believe to be the most basic aspects of our reality should not be seen as entities properly existing in their own right.   Instead, they appear to be permanently subject to external influence in manners suggesting they are primarily cognitive inventions – at least inasmuch as they cannot be properly identified or isolated within what we believe to be the physical world.

The unthinking position tacitly adopted within conventional physics remains a presumption that reality is formed from effectively discrete entities or phenomena – or variables – a position nonetheless arguably only the result of how human abstract thought functions.   It certainly appears inconceivable that our minds would evolve the form of abstract thinking we use everyday in a manner that did not attempt to differentiate the world.   For obvious reasons, we want to distinguish land from sky and sea.   The act of identifying bits of reality seems utterly central to the mind’s ability to model the world and label it up for whatever ends it pursues.   Hitherto successful thinking about reality can nonetheless be imagined as different from an optimized way of seeing reality.   And if it is logical that nothing can be truly static, human civilization and human ideas are anything but.

Physics has pushed for many centuries to resolve the challenges of making exact measurements, and has generally just regarded the associated difficulties as inconveniences.   Within its rather unthinking conviction that the human mind’s mode of thinking is basically sound, it has never concerned itself with the philosophical implications that nothing at all can be proven to exist independently.   And yet, with the possible exception of quantum physics, physics seems to have succeeded in unwittingly demonstrating that anything the human mind identifies is permanently subject to influences that mock any idea such a thing has a properly discrete existence.   At the very least, it seems we must accept that if anything does have such a truly discrete existence, that existence is beyond our detection.   And although quantum mechanics has not actually destroyed objectivity and the everyday idea that one thing affects another, it certainly suggests conventional approaches to understanding the world may be built on shaky foundations.

As regards NOR, the suggestion is that the objects and phenomena we imagine populate our reality are just the most convenient generalizations in terms of classifying the world around us for practical purposes; they are not separate entities in the way that our different concepts and labels suggest.   And they are perhaps best understood as ultimately entangled, rather than discrete – albeit using such a word is certainly easier than imagining quite what might lie behind its seeming appropriateness.

It is obvious that land, sea and sky do not have exact and unambiguous dividing lines where the one thing becomes the other, but it is common in physics to see time, mass and energy as properly discrete.   The point here is not to argue that such things are not discrete; it is instead to argue that the case cannot be proven either way despite extensive efforts that have indirectly sought to argue one side without even contemplating the other.

Moreover, when such uncertainty exists for what are believed to be the most basic building blocks of reality, what are the implications for all our more mundane and less exacting ideas built on the unreasoned subliminal presumption that seeing reality as a collection of things or objects is legitimate beyond question?

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The above article states ” … a ruler made from a metal more or less stable under temperature changes is obviously preferable to one using a metal that changes size significantly with temperature variations.”   Reading that statement a couple of years after writing it is revealing in terms of how psychology impacts physics.

It raises a question: why do we think that way about measurement?   Why, if I want to measure a certain length of copper for example, would it not be better to get a ruler made from copper so that it expanded at the same rate as the copper I was measuring?   Of course, the obvious answer is that such a measuring device would only be good for copper.   But a bigger question concerns the observation that physics and science in general are, through their attitude to all forms of measurement, perpetually imagining our universe to be far less flexible than it really appears.

In addition to the main points of the article, we can see that the very goal of accurate measurement includes a subliminal attempt to intellectually circumvent the constantly changing nature of our universe.   Is that clever?   It is as if science imagined it could somehow stand outside the universe and then measure how that universe was behaving.   But the various points of the article – not to mention common sense – tell us this is a silly notion.

There is also something troubling about the idea that, where two things are being compared, one of them – the measuring device – supposedly provides a reliable reading – just because it seemingly displays less variability than the other.   If we wish to understand our universe better, we must accept that not only is it variable, but it is variably variable.

In any case, is this not another example of how the principles of relativity apply to everyday matters?   The idea that there is a knowable true measurement of anything at all seems suspect when everything physical is logically and evidently undergoing continual change.