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There have been many technological advances in the fields of chemistry physics in the past, but the most significant of those have been in physics in the last two hundred years or so. As a result of this observation, when considering evaluations of past achievements, I shall be limiting my discussion to approximately the last two hundred years, using mainly (if not exclusively) the physical examples that I find most relevant. I shall also outline these achievements, and their relative merits, in chronological order, so as to give some idea of how science has evolved (to use a more biological term), and hopefully build better foundations for my ‘insight’ into the future.

Evaluation Of Past Achievements:

As it plays such an important role in our everyday lives it seems sensible to start with the discovery of electricity, without which this essay would not be in such a readable format.

Ever since the ancient Greeks, the electrostatic effect has been known. Back then, and in fact up until the start of the 1800’s this was just considered as a strange observation – an attractive effect caused by rubbing a silk cloth on, say, a piece of amber (incidentally call elektron in Greek!). However, with the development of Newton’s laws in the 1660’s and the ‘birth’ of physics as we now know it, there was considerably more interest in describing attractive forces using mathematical equations, than there ever was before. This interest lead to investigations by people such as Gray and Coulomb on the nature of the electrostatic force, and then, once Volta had created the first ‘Voltaic Cell’ in 1799 (what we think of as a ‘battery’), many more similar investigations were launched in the new exciting field of electrical current research. By 1827 Ampère had produced a summary of the majority of work in a series of mathematical papers and experimental observations, which we still use to describe the macroscopic properties of electrical current today. A little later in the 1830’s Faraday’s experiments (based around those of Ørsted) lead to the laws of electromagnetic induction (due to the properties of electricity and magnetism being inextricably linked, as he started to prove in 1845) which we also use today to create and distribute electricity, and also to make electronic switches in circuits called capacitors – an integral part of almost every modern electrical appliance.

I don’t really need to push to hard to make you see the importance of these experiments. They provided, in the short period of about 50 years, the basic laws upon which nearly all modern electronics is based. And as electrical appliances are so influential in our everyday lives, the work of these pioneers of electronics lives on in nearly everything we use. Without these discoveries, we would not have our very important radio and televisual communications networks (later), good refrigerators, life support machines, (practical) vacuum cleaners, washing machines or computers to name just a microscopic sample of uses. And furthermore, without computers, or more generally the laws concerning the behaviour of electrical currents, it’s probably safe to say that we wouldn’t know even a small amount of the things we do in all other aspects of science. This is because so many tasks rely on monitoring by electrical apparatus and/or modelling by computer, the structure of DNA and the mapping on the genome being good examples of where both these aspects come into play.

Faraday’s experiments, along with the work of Ampère, Coulomb (and also Gauss), provided the framework of what we call classical electrodynamics, but it was the work of Maxwell in 1864, which really started to close the book on what electricity is. Maxwell was more skilled at maths than Faraday and, using new data came up with four equations that surmise the behaviour of both electricity and magnetism together. He was also the first person to realise that light was (what we now call) an electromagnetic wave and could be treated mathematically using equations that are similar to those used for waves on a string. His work provides the grand unifying theory of electromagnetism, and is really the last word when it comes to understanding how electricity and magnetism interact, and how this can be applied to benefit us.

His work on electromagnetism isn’t really of much interest to people outside of physics or electrical engineering. All it does (although this shouldn’t be treated at all half-heartedly) is provide the theoretical basis for the empirical work done by Faraday, and it’s these equations that we use to model the interactions of electrical systems today. What is of more use to everybody is his description of light as an electromagnetic wave, as it was this that led to the work of Hertz, Marconi and Logie Baird.

Hertz, using Maxwell’s idea of electromagnetic waves, first showed the existence of radio waves produced by an electric spark, and in 1888 showed that a tuned circuit up to twenty meters away could detect them. He then went on to show that these waves could be polarised, reflected and showed all other properties of ’standard’ light (the portion of the electromagnetic spectrum that we see), which was an important piece of supporting evidence for Maxwell’s idea (as it lead onto the investigation for other types of electromagnetic radiation). Hertz died very young, but soon after his death Marconi improved the design of the radio equipment that he used, and showed that radio waves could be transmitted over 1609 meters (approx. 1 mile). Marconi then proceeded to capitalise on ‘his’ invention by interesting the British government in the technology.

Ever since electrical current had been discovered, and it had been shown that wires could carry electrical pulses, the telegraph had become the fastest and most important form of communication, apart from letter writing. The telegraph system was adopted widely in Britain, and Morse code was used to send messages all over the UK and the rest of the world through a network of cables. As the British Empire was built the telegraph became an even more important means of communication, however a problem arose when distant points, such as countries or ships at sea had to be connected up to the system. This is where Marconi came in. He convinced the British government that radio transmission was a real alternative to the cable based telegraph, and in 1899 he made the first transmission across the English Channel, and radiotelegraphy was born. This transmission caused much interest from the Royal Navy and other parties wishing to exploit the invention, and the system soon became widely adopted as the means of communication in the developed world. Marconi also made the first Trans-Atlantic broadcast in 1901 via a crude satellite system, which consisted of a kite-born antenna flying above Newfoundland in Canada. In 1915 an American company transmitted the first good quality audio radio signals from Virginia to Paris. By 1927 he had created a worldwide communication system based upon this technology, which was to change the field of communications forever.

Again, it’s not hard to see what an impact this has had on the world. We live in an age where the use of communications technology is second nature to us, and provides us with a vast majority of our entertainment. For example, if you live in Britain and want to talk to you family in New Zealand, all you need do is pick up your telephone and dial the code for their telephone, and you can speak to them in a second not weeks, which is what it could have taken (via letter writing) before international radio communications had been developed. In fact nowadays, thanks to John Logie Baird’s invention of television (based on the same principles of radio communication), you can ‘video-chat’ to your family, and actually see an image of them as you talk, or send an instantaneous ‘virtual’ (i.e. doesn’t really exist) letter via e-mail.

The properties that radio waves have also forms the basis for radar detection, a technique that was very influential on the outcome of the Second World War.

Around the time of Marconi’s first Trans-Atlantic radio transmissions, there was a lot of research beginning into the very nature of matter itself. The beginnings of nuclear physics started with J. J. Thompson in 1897 when (under improved conditions of vacuum) he discovered that cathode rays could be influenced by a magnetic field. As a result he thought that the rays had a particle like nature, and he therefore tried to measure the charge and mass of this particle. In each experiment he found that the particle has a charge opposite that of a hydrogen nucleus, but was about 1000 times less massive (lighter), no matter what the material was that he used for the cathode. This particle became known as the electron.

Later Rutherford took over from Thompson’s studies and after many experiments on the radioactive decay found in uranium by Becquerel in 1896 and in polonium by Curie in 1898 he deduced (also) in 1898, that there were two types of radioactive ray, alpha and beta. Alpha rays were the weakest, and are helium nuclei; beta rays were stronger and were like Thomson’s electron. Later on in 1900, he also discovered gamma rays, which are very high-energy electromagnetic waves (more evidence for Maxwell’s idea). But it was while working with Geiger that he produced his most important discovery. This was that when alpha particles were fired at a piece of gold foil, they all passed through, except the odd one, which came straight back. In his own words, he described it as ‘…quite the most incredible event that has ever happened to me in my life… It was almost as if you fired a 15-inch shell at a piece of tissue paper and it came back and hit you’. This effect led him to deduce in 1911 that the atom consisted mostly of empty space with a small positive nucleus. From this Bohr created the modern picture of the atom by applying (old) quantum theory to Rutherford’s model, and coming up with a solar system type arrangement, whereby electrons orbit the nucleus. Rutherford was also involved in the first nuclear fusion reaction in 1934 when deuterium was bombarded with deuterium nuclei to form tritium (which are all forms of hydrogen, but with different masses).

These discoveries lead to the complete modern picture of atomic structure, which is very important to chemists as it describes how and why reactions may or may not happen, and has lead to many the creation of many new substances that we use everyday. Also the discovery of radioactive decay is very useful in both medicine and industry, where it is used for detection purposes (but in very different ways). Also there is additional evidence for Maxwell’s idea of electromagnetic waves, which again encouraged others to look for other different waves, leading to x-rays (useful again in medicine and industry), infra-red which is useful for detecting heat sources (such as human bodies) in otherwise opaque conditions (a smoke filled room for example) and microwaves can be used to cook food very quickly in microwave ovens. Most importantly though it lead to experiments on nuclear fusion. These experiments were important as nuclear fusion lead to the creation of the atomic bomb – not in itself a good use for this principle, but it did show that the theory works. The bomb lead onto the idea of ‘clean’ atomic energy generation, which is either good or bad depending upon which way you look at the ‘problem’ and also lead to the cold war between Russia and America.

The Second World War, which was the next significant period in history, led to the development of many new things such as jet aeroplanes, rockets, atomic bombs, computers and a whole host of other things besides. The development of these technologies continued after the Second World War and, as I stated before, sparked of the arms race for technical superiority between Russia and America. The cold war was again unfavourable but, in my view at least, it was very useful in getting funding into science and advancing technology at a rate of knots. For example, the technology from building missiles has enabled rockets to be propelled into space, and men to visit the moon. This is the very beginning of our exploration of space and has lead onto the idea of space shuttle services, and possible future colonisation of other planets such as Mars. It has also lead to the vast and excellent international communications network we now have via the ability of placing satellites into orbit. There is also the Hubble telescope which has provide the best pictures we have so far of distant galaxies, and has allowed us to say a bit more about what our universe is, and what our place is in it.

LASER technology is another important advancement out of the cold war. It allows us to communicate along phone cables at the speed of light, listen to digitally recorded music in a way that never degrades the recording, and allows us to have tumours removed or other such precise surgery performed with a minimum of physical damage to us.

Modern technology is increasingly being controlled automatically by computers, mainly through necessity than choice. The first digital computer to be designed was by Babbage in 1823 after other related inventions, such as a small calculator that could perform certain computations to 8 decimal places. But the beginnings of modern computers didn’t surface until around 1940, and then it wasn’t until the 1960’s that they became particularly powerful, with the advent of computer languages and the birth of computer science. But again they have become an integral part of our everyday lives, both in terms of communications and entertainment, as well as other practical applications like controlling the washing machine or the microwave oven.

I think that just about wraps it up for advances in physics as I’m leaving out the whole of quantum mechanics. This in itself is a very important advance for physicists as it allows them to describe very accurately the microscopic world, where the macroscopic laws of physics don’t always hold true, but it hasn’t had much practical application yet other than in things such as LASER’s and also very tiny integrated electrical circuits, such as on a computer chip.

So what about the future?

Well the future still has capacity for many new inventions and advances in physics, even though the subject seems to have already passed ‘through its golden age’. The science of modern physics involves quantum mechanics in every aspect, and is basically the science of the atom, and of the microscopic properties of matter. In this vein it tends towards the more physical aspects of chemistry and materials science, but is different enough not to be considered as such.

Recent developments hold speculation of the possibilities of quantum computing, which is a big buzzword in physics at present. The problems involved with creating a quantum computer are vast, but real efforts are being made to create at least preliminary designs. One of the advantages of such a computer is its possible high speeds and its ability for performing great numbers of calculations in a second. One of the problems with modern computers is that the design, and the basic theory behind the way that they work hasn’t changed really since Babbage. In a quantum computer however, the whole theory behind the way that the computer performs calculations will have to be rediscovered as the mechanics is so different, and once a computer is built it will be a long time before any real programming can be done on it. It’s also very unlikely (from a present point of view) that this technology will be available as home PC’s because it is so fragile. However it could form the basis for a network of home terminals in a community, which could be accessible via a TV set like apparatus, similar to that which is already happening with cable TV!

An alternative (or a compliment) to a quantum computer may also be a computer with circuits that have light flowing through them rather than electricity. This technology is also in its infancy, but it is probably more likely to succeed, as the conditions it requires are much less fragile than those required for a quantum computer. Other reassert on light based computing involves the storage and retrieval of information. A weird and very interesting piece of information storage research is based around small ‘glass’ cubes that can hold the same amount of information as 1000 DVD’s or approximately 700000 floppy disks, using lasers to excite the ‘glass’ molecules (ref. New Scientist 10th March 2001, page 25). Note that although light based circuitry and storage would be influenced greatly by quantum effects, it is considered to be different to quantum computing as it still uses the classical computational methods, just in a faster and more efficient way.

The applied science of physics is really moving into communications technology and both these examples show this.

One of the other main branches of physics that warrants attention is also based upon atomic physics, and that is the search for a renewable energy source. This is either by utilising the same fusion reaction that the sun undergoes, or by controlling the energy produced when hydrogen and oxygen react explosively to form water (as is used in rocket fuel). Both of these things are also considered as ‘Holy Grails’ in physics at the moment, and again, a fair amount of research is being done on this subject, but there is no real evidence that our cars are to be powered by mini-sun’s or rocket fuel in the immediate future.

Lastly, although I consider it as a bit of a cliché, there’s the standard glimpse of space travel and of colonisation of the rest of the universe (or at least the solar system). This is not now so far off, as it seems. In the last couple of days, the first commercial space passenger has returned to earth with a great reception, and more and more probes and equipment are being sent to mars in anticipation of the first manned ‘flight’ there. It will be many years before the solar system does start to become colonised, and it will probably proceed via ‘planet hopping’ if another suitable host planet (or moon) (other than Mars) exists that can be colonised, as it would take far too long to travel directly from the Earth. This is unless we find a way of moving very fast through space using methods other than the standard rockets we use today – but who can say. Quantum mechanical experiments may yield new fuels and methods of propulsion, but again these are far off as yet, and may never happen.

For now, we will just have to wait and see…