Physics, investigating the real World.
Physics is the study of reality, the physical properties of space, matter, energy & time. In 20th century academic circles it became increasingly divorced from Electro-Magnetics & Electronics.
This separation is artificial, presenting a barrier to the discovery & application of genuine new knowledge. Without application, knowledge is essentially sterile, a curiosity, discussed in academia & eventually forgotten. Physics should go back to being a practical science.
The Physicist's Motto:
We have made a cage of overly intricate mathematics, & placed reality inside. So it can serve us alone.
These pages will feature my perspective on current knowledge & practical applications.
Mostly covering areas relevant to my work & experience.
All that is 'known' is based on human experience (practice) or on thinking about it (theory). Physical laws have been found by experiment or postulated to fit results. Some of these are considered to be absolutes, cast in tablets of stone. We are all capable of being wrong & should be prepared to change our beliefs if overwhelming evidence suggests so.
Without an open mind, science ceases & a form of religious dogma takes over. Further real progress is halted. This has happened before, (the dark ages), we must prevent it doing so again
"I make no personal claim to the truth, only the right to seek it, prove it in argument, and to be wrong many times in order to reach it." (Filipo Bruno).
Science originated when ancient man tried to explain the world around him & his place in it. As he learnt more about the workings of nature, that knowledge was put to use. So early scientists were practical people, more what we call engineers today.
To be continued.
The universe has four entities, space, time, matter & energy. The latter two are manifestations of the same entity. According to the theory of relativity the first two are combined in a single entity "space-time". Thus it becomes 2 entities, the intangible & the tangible.
Space is generally thought of as a vacuum, the apparently unlimited expanse of nothingness in which all matter & energy exists. We assign three dimensions to any particular portion of it, to define its size.
This is possibly the most difficult for our senses to grasp. They give us perception of what is around us, what 'is there'. Space, on the other hand, is not anything, it simply is 'not there'. We have to give it size, shape & form in order to talk about it. We can never experience it, we can not exist in it, or touch it.
We can send vehicles through a small part of it, we can even travel in those vehicles. This is not the same as experiencing limitless nothing. Our theories can only reflect our experience.
Time, the '4th dimension'. The continuum of existence from the past, through the present, into the future. The passage of time is essentially negative, the Universe, at its creation, was accorded a quantity of time. A lot of it, by our system of measurement. Every instant that passes is subtracted from that quantity. Everything we do or avoid uses up some of our time.
The past is time that has elapsed & is no more. The future is time yet to come, what it holds for all is a matter of conjecture. The present is a dividing line between the two, a fleeting instant that we are currently experiencing. For us this is the only reality.
Matter and Energy.
Matter & energy are 2 aspects of the same entity. Electromagnetic phenomena ocurring in space & filling its emptiness.
To be continued.
The speed of light (c), the universal variable.
The speed of light (c), the universal variable.
Much of scientific "knowledge" is based on assumptions, old or new. Much of the remainder is based on conjecture, recent or early. What is left comes from empirical measurement, generally the accuracy with which such data is collected improves over the years. Mainly due to greater experience & better technology.
Many scientists prefer what is called pure science, not adulterated or contaminated by any hine of a practical application. Putting knowledge to use is considered somehow dirty & commercial. Possibly akin to using art to generate a living, rather than just for expression. This type of scientist does however increasingly need commercial applications & technology to make further discoveries possible.
The speed of light in a vacuum has long been considered to be a constant. Much effort has been expended, over the centuries, in measuring it, using incresingly sophisticated techniques. It is now generally considered that its value is known, to a high degree of precision.
Physicists are so confident of the accuracy with which they can measure c, that now the length of the metre is specified in terms of it. As the distance travelled by light in 1/ 299,792,458th of a second. This of course is a circular definition, akin to the length of the proverbial piece of string. I will explain this later.
There are anomalies, in many areas of study, that bring current knowledge & values into doubt.
My solution to some of these problems is simple. The speed of light is not a constant, it is a variable.
The only thing constant about it is that it is constantly varying. The principle of Ockham's Razor is that unnecesary complication should be avoided. If a number of possible explanations fit the facts, the simplest is more likely to be correct.
Why should the speed of light be 299,792,458 metres per second? Why should it not be some other value? How can such an important parameter be cast in tablets of stone, at some arbitrary value, for ever? In fact this number is a purely human construct, I will elaborate on this later.
Physicists decided they know the speed of light more accurately than they can measure the standard metre. So they have redefined the metre as the distance light travels in a specified fraction of a second. Yet the speed of light (c) is defined as the number of metres it travels in a second.
This is equivalent to measuring a car's top speed as 90 miles per hour. Then deciding that no tape measure is available to accurately measure a mile. So the mile is redefined as the distance the car travels in 1/90th of an hour.
It gets worse. To measure the speed of light an accurate measure of time is required. How is this achieved? By using an atomic clock, this employs the spin rate of an atom's electron as a standard. What controls this spin rate? That's right, the speed of light,
So the speed of light is measured by dividing a value derived from it by another derivative. My fanciful way of defining the mile now seems quite sensible. The hour can therefore be defined as the time the car takes to travel 90 miles. Why are scientists often seen as not quite having their feet on the ground?
Why c is changing, anomalies throughout the Universe.
Improvements in telescopes over the years have enabled astronomers to see stars further away. It was discovered that the light from the most distant is shifted towards the red end of the spectrum. The most likely cause is Doppler shift due to motion away from us, the concept of the expanding Universe was born.
The 'big bang' theory for the origin of the Universe was postulated. This has much to commend it, it explains many observed phenomena. Some predictions resulting from it have since been verified. This is not proof, incorrect theories have, in the past, spawned correct predictions. It will probably do, until its turn comes to be verified or dis-proven.
More recently an apparent anomaly was discovered, regarding light from the most distant stars. This was more red shifted than those less far away. It seems that the oldest stars we can see are moving away faster than those nearer. In other words the Universal expansion is apparently accelerating.
Many theories have been put forward in an attempt to explain this observation. Some form of Universe wide repulsive force has been proposed, pushing the matter in the Universe apart.
This so called 'dark energy' works in the opposite way to all known energy & matter. Pushing galaxies & stars apart at ever increasing rates.
It seems that physicists & astronomers are caught up in their own cleverness. They can't see an obvious explanation if it's about to bite them. The basic laws of mechanics may play a part. An explosion starts with rapid acceleration, then slows down. Just look at any explosive firework rocket on Guy Fawkes' night, as it explodes.
The hot bits quite obviously expand apart rapidly, slowing until they stop. The debris then falls to the ground, this is because the Earth's gravity swamps any other force. If the Earth was not there the particles may fall back together. Without the air's friction, slowing would take longer, controlled only by mutual attraction.
The outermost bits will tend to stop first, they have travelled further. Then start to move back towards those particles still expanding. At this point the centre of the explosion may be empty, all matter having been ejected outwards.
Two possible final outcomes. If total kinetic energy overcomes the mass' attraction, expansion will continue unchecked. If mass atraction overcomes kinetic energy, all matter will eventually collapse towards the centre. Astromomers use the letter Omega for this ratio, (see note at end of section). It is theorised that an Omega of unity (1) will result in a stable fixed size. This can only occur, temporarily, if part of the outward motion is circular.
If this model is used for the universe a number of simple explanations for the red shift are possible. The most obvious is that the outer stars are further away. The light we see from them is from a time when they were moving faster, as were the nearer stars. By now they may be much slower, even stopped altogether or heading back towards us.
Another, more fundamental, explanation is that c was faster when the light from those stars started out. Since then light has been slowing, together with the frequency of that light. Hence the red shift, which will be greater with increased distance. So the Universe may no longer be expanding, for all we know it may be contracting.
Both possibilities suggest that at some time we will need to duck, they may both be right. It is probable that, at the time of the 'Big Bang' light travelled much faster, possibly by an astronomical ratio.
In any case stars further away than those yet discovered may be more red shifted. Possibly into the infra-red or even radio frequencies. Radio telescopes are difficult to focus with sufficient accuracy to pick out individual stars, but this problem needs to be addressed, in order to find them.
We Wish ALL the Universe Peace, Justice, Equality, Prosperity & an End to Fanaticism.
A Static Universe.
Yet another, less likely, possibility is that the Universe is static in size. The red shift being solely due to the gradual slowing of light. I do not give this one much credence.
If I am right it is likely that some estimates for the age of the universe need to be revised. The premise of expansion on which they are founded being wrong. The Hubble measure, based on white dwarf's decay, is not affected. The likely accuracy of this is another matter.
Note: Omega is actually specified as the ratio of the Universe's density to a critical density. This critical density is variously estimated to be 1 to 8 hydrogens atoms per cubic yard, or cubic metre. This seems to be nonsense, it does not matter how massive the Universe is, just the ratio between that mass & its kinetic energy.
Whichever way it is specified, an Omega of 1 means there is just enough mass to eventually halt expansion. It is theorised that for that one ratio a static Universe will result. This is not possible, for several quite clear reasons, some of these I will outline further on.
An Omega of less than 1 means there is insufficient mass for gravity to eventually halt expansion. The Universe will expand unchecked, although slowing. An Omega greater than 1 will result in expansion being halted by gravity & then reversed. All the matter will collapse back to the centre.
It is possible that a singularity will result. The 'cyclic' theory suggests that time will halt briefly, its momentum causing it to reverse, another 'big bang'. Thus the whole process of creation will take place again, an elegant concept but evidence of its veracity has not been found.
To be continued...