Category Archives: Technology

Britain, Defence, Government, National Security, Society, Technology, United States

Menacing spies in the sky

NATIONAL SECURITY

ABOVE our heads – some 80,000 feet up – a high-tech tussle is under way, with our most closely guarded secrets and our national security at stake. The shooting down of a number of intelligence balloons in recent days seems closer to a fictional tale rather than the serious threat they pose.

Four mysterious aircraft have been shot down in just nine days over North America, three by the US Air Force and one by the Royal Canadian Air Force.

The fictional perspective was primed when an American general sparked a storm of speculation when he said that he was not excluding extra-terrestrial origin for these intruders. General Glen VanHerck, commander of North American Aerospace Defence Command, when asked about the possibility of aliens, said: “I haven’t ruled out anything at this point.”

For these are – quite literally – unidentified flying objects. The language used to describe them recalls the unexplained sightings that, for decades, have puzzled even seasoned observers. UFO enthusiasts are enthralled. In 2021, the Pentagon set up the Airborne Object Identification and Management Synchronisation Group to investigate more than 100 incidents.

One of the aircraft, downed last week over Alaska, was described as “cylindrical and silverish gray”, about the “size of a small car” and with “no identifiable propulsion system”. Another, brought to earth on the US-Canadian border, was a “small, cylindrical object”.

Such intruders may also have crossed British territory. Rishi Sunak, newly enthused by military matters, says we can and will shoot them down if necessary.

Defence Secretary Ben Wallace has ordered a review. For now, the questions are multiplying. Are they Chinese? The West seems to think so. The regime in Beijing has protested about the downing of two of them – just peaceful weather balloons, it insists.

Security officials in the West say that China’s stratospheric surveillance programme has operated for many years, and over five continents. It is the brainchild of the Strategic Support Force, a secretive component of the People’s Liberation Army. So, why now? Why have we not noticed this before?

The short and probable answer is that we weren’t looking. These balloons and drones move incredibly slowly at great heights. Our air-defence radar works at lower altitudes. Our missile defence-systems track fast-moving rockets. US officials are now scouring data collected in previous years for signs of intrusions that they may have missed. So far, the Pentagon says, four previous instances have been identified.

In any case, malevolent intruders can easily be missed amid the thousand of innocent weather balloons launched every day. Gathering meteorological data provides perfect cover for covert missions. China counteracts claiming that the US has repeatedly sent spy balloons into Chinese airspace. The Americans deny this.

THREATENING

THE question looms as to why China would invest so much in these missions when it has more than 260 spy satellites? Being only 15 miles above the earth’s surface – satellites are seven times higher – gives them a clear edge in taking photographs and hoovering up electronic information, such as the ultra-sensitive “friend-or-foe” systems that prevent us shooting down our own warplanes.

These satellites can loiter over sensitive military installations, such as the RAF base at Boscombe Down in Wiltshire, used by American spy planes. Gathering information about the temperature and density of the air at high altitudes could also give a crucial advantage to missile-guidance systems. These spycraft may also be sent to test national defences.

Most worryingly, China published in 2018 a video showing a balloon being used as a platform to launch hypersonic weapons. These can travel vast distances at high speed, evading our defences and delivering either nuclear warheads, or electromagnetic pulse blasts that devastate all electrical and electronic devices.

What keeps these machines aloft and on course, thousands of miles from home, nothing is said.

Some clues, however, may come from here in Britain. We have Stratospheric Platforms, a company that offers internet access from a drone that can stay in the atmosphere for a week at a time, powered by a hydrogen engine. Another British start-up, Avealto, has a solar-powered craft in orbit that targets the same market.

Speculation abounds about even more advanced technologies. Aviation experts are eagerly awaiting news from the wreckage of the recent devices shot down.

Could, for example, the Chinese have cracked the difficulties of “ion propulsion”, which uses blasts of electrically charged air to stay aloft, and requires no combustion or moving parts like propellers or jets?

Prototypes of aircraft using this technology already fly, but they use too much electricity to be viable. Or so we think.

Whatever the case, the wreckage recovered from the recent incidents’ will be eagerly inspected by American military technologists hoping to gain an edge in the battle against spy wars in the sky. The results of their investigations will be classified secret. Why give clues to the enemy?

One thing in this extraordinary story is clear. These balloons are far from innocent and have caught the guardians of our security napping. Vigilance has been poor.

Standard
Climate Change, Government, Science, Technology, United States

Nuclear fusion: A breakthrough that will lead to clean energy?

NUCLEAR FUSION

A REVOLUTIONARY scientific breakthrough is thought to have brought humanity a step closer towards limitless clean energy from nuclear fusion.

Since the 1950s, scientists and researchers have been working tirelessly towards the “holy grail” of creating more energy from nuclear fusion than they put in.

Now US government scientists in California have reportedly done it, by aiming the world’s largest laser at a nuclear target the size of a peppercorn.

The result, from a nuclear reaction reaching three million degrees Celsius, is apparently 2.5 megajoules of energy, from 2.1 megajoules of laser energy.

Nuclear fusion is preferable to nuclear fission, which is currently used to power the planet alongside fossil fuels and renewable power.

That is because nuclear fission splits heavy atoms like uranium or plutonium, to create energy, producing potentially dangerous radioactive waste that must be stored.

Nuclear fusion creates energy by bringing atoms together, instead of splitting them, and has no waste products, making it clean energy.

Unlike coal, the supply is limitless, usually requiring just two materials called deuterium and tritium, which are slightly different versions of hydrogen and found in sea water and mineral springs.

A small cup of this fuel could one day be used to power a house for hundreds of years.

The breakthrough at the federal Lawrence Livermore Laboratory in California was achieved using a laser pulse amplified a quadrillion (a million billion) times and split into 192 different pulses.

These enter a hohlraum – a gold container – and hit a tiny capsule of deuterium and tritium, creating shockwaves which produce vast amounts of  energy, in a process called inertial confinement fusion.

Significant engineering challenges remain, including how to cut the cost of nuclear fusion, harness the energy produced, run it through a turbine and get it into the National Grid.

Most experts believe this won’t be possible until 2045, but some say it could be done in a decade and is likely to be achieved using a different type of nuclear fusion called magnetic fusion.

But whether it is using magnets or lasers, the experts agree it is the main hope for escaping the climate crisis.

Sir Robin Grimes, professor of material physics at Imperial College London, said: “This is a key step towards commercial fusion – the technology which will ensure our survival on Earth, providing enough energy, with a low impact on the environment, to hugely reduce our contribution to climate change.”

Jeremy Chittenden, professor of plasma physics at Imperial, said: “If what has been reported is true and more energy has been released than was used to produce the plasma, that is a true breakthrough moment.”

Nuclear fusion, if it can be scaled up and made to run more continuously, could in future be almost zero-carbon.

However, some experts point out that the amount of energy used for the entire system containing the laser means, technically, scientists are unlikely to have yet produced more energy from nuclear fusion than was put into it.

The US energy secretary, Jennifer Granholm, made the announcement of a “major scientific breakthrough”.

– Diagrammatic representation of how nuclear fusion works. Source: BBC

Standard
Education, Information, Science, Society, Technology

Information Society: Probability and Statistics

INFORMATION AGE

WE live in an information age in which modern technology makes it easy to gather large amounts of information on almost every aspect of our lives. However, on its own this information is of only limited value – it needs to be organised and analysed to be of practical use.

 

INFORMATION about population numbers have been collected since ancient times (see Appendage), but the science of analysing and making sense of data – statistics – is relatively recent. Although now not usually considered to be a branch of mathematics, statistics relies on mathematical analysis to interpret information and is closely linked to the area of mathematics known as probability theory.

Chance and probability

The beginnings of probability theory came from the fascination that two 17th-century French mathematicians had with games of chance. Blaise Pascal and Pierre de Fermat discussed, in a series of letters, a method of calculating the chances of success in gambling games, and they were the first to give the subject of probability a scientific treatment.

What they discussed was a mathematical way of determining the probability of a particular outcome occurring in a random event, such as tossing a coin or throwing a dice. When a coin is tossed there are two possibilities: heads or tails. Each is equally likely: there is one chance in two that the coin will come up heads (or tails), or in other words the probability is 1/2. The six faces of a dice give one chance in six of throwing any particular number, a probability of 1/6. In games using more than one dice, or a deck of cards, or a roulette wheel, the calculation becomes more complex but is essentially built from basic principles and is the same. From this discussion of gambling games, a theory of probability evolved.

The idea was further developed by the next generation of mathematicians. French mathematician Abraham de Moivre discovered a pattern to the probability of outcomes, now known as normal distribution and represented graphically as the bell curve.

Bell Curve

[Bell Curve: Normal distribution] – When certain values (such as height) are plotted against the number of occurrences of that value (how many people are of a specific height), the result is often a bell-shaped curve – the normal distribution. The most common value, at the peak, is the mean (average).

British mathematician and clergyman Thomas Bayes took de Moivre’s ideas further with his theorem of conditional probabilities, which makes it possible to calculate the probability of a particular event occurring when that event is conditional on other factors and the probabilities of those factors are known. Bayes’ work was further developed by Pierre-Simon Laplace, a French mathematician and astronomer whose application of Bayes’ theorem to real cases led to a new field of study: statistics.

Detecting patterns

The pioneering work in statistics was done by de Moivre, who used data about death rates and rates of interest to devise a theory of annuities, which enabled insurance companies to compile tables of risk for life assurance based on scientific principles. This application of mathematics to data in records was at first known as “political arithmetic”, and, as patterns emerged in collections of data, research began into their underlying statistical laws. To begin with, statistics was concerned with social issues, and advances in sociology and criminology were made by the Belgian mathematician Adolphe Quetelet, who introduced the concept of the “average man”. He also believed mathematics lay at the heart of every science, and statistical analysis could be applied to data of all kinds. Perhaps the area where this had greatest effect was medicine, where an important new study, epidemiology (occurrence of disease in populations), developed from medical statistics.

As more practical use was made of probability theory and statistics, the mathematics behind them was developed by various mathematicians, including the Frenchman Adrien-Marie Legendre, the German Carl Friedrich Gauss, and the Russian Andrey Nikolaevich Kolmogorov, whose systematic approach to the subject forms the basis for much of modern probability theory.

Modern statistics

Statistics plays a key role in much of modern life. Governments collect and analyse a wide range of personal data to detect patterns that can help shape policies. Businesses use market research to gather information about potential customers and apply statistical methods to analyse the data. In science, statistics and probability are central to subjects such as quantum theory and are also essential to many other subjects, from psychology and economics to information science.

Data Samples

In practice, the data used for statistical analysis must be sound for it to produce useful results. The data must be collected using a valid method that measures what is intended, and the data must be accurate. It is also essential that the set of data is large enough and constitutes a representative sample. For example, in general public opinion polls the right questions must be asked in an unambiguous, neutral way; sufficient numbers of people must be polled; and, as a whole, the respondents must be representative of the population (for instance, in age and gender).

Applications

Coxcomb2

Florence Nightingale’s “coxcomb” graph – This graph devised by Florence Nightingale shows the relative causes of death among soldiers in one 12-month period during the Crimean War (1854-56).

. Coxcomb graphs – Working as a nurse for British troops during the Crimean War, Florence Nightingale kept records of troop deaths and later used the information to create what are now called “coxcomb” graphs. These highlighted the number of deaths that were not directly caused by combat but by factors such as wound infection and disease.

. Computerised Modelling – The development of probability and statistics gave scientists new ways to analyse and conceptualise the physical world.

Many natural systems are influenced by numerous factors and exhibit chaotic behaviour. For example, influences on the weather include air, land, and sea temperatures, winds, sea currents, humidity, and the amount of sunlight. Minute changes in any one of these factors can have a profound effect on the weather. Because of this, weather forecasting relies on numerical models in which statistical methods are used to arrive at predictions that have various degrees of probability of being correct.

. Quantum Theory – The currently accepted theory of the nature and behaviour of matter at the subatomic level, quantum theory uses probability as one of its fundamental tenets. For example, according to quantum theory it is impossible to know precisely the location and momentum of subatomic particles such as electrons “orbiting” the nucleus of an atom; it is only possible to specify regions – known as clouds – where particles may be located with the highest probability.

Appendage –

Early Censuses

The earliest known census dates from ancient Babylonian times, about 3800 BCE, and recorded the human population and agricultural data.

Many of the other ancient civilisations also regularly recorded population numbers, often for the purposes of taxation. In the Middle Ages, probably the best-known census is the Domesday Book, which was instigated by William I of England in 1086 to tax the recently conquered population. These early censuses were simply records of numbers because mathematical techniques for analysing data had not yet been developed.

Standard