Advanced science, Bangladesh, Cultural, Disasters - natural and man-made, Economic, Environmental, International, Life as it is, Literary

Keeping up with Time

A new title “Keeping up with Time” has now been published and released to the http://www.amazon.co.uk website. The book is also available through book retailers in the UK like Waterstones, Foyles etc. The link to Amazon UK website is

Keeping Up with Time: Amazon.co.uk: Rahman, Anisur: 9781838468613: Books

The excerpt of the book is:

At the present time, we see that facts are quite often manipulated and even manufactured to suit the purposes of the presenter. The mendacious molestation of facts, which is generally called the ‘alternative truths’, alters the perception of events and makes readers deeply suspicious of the authenticity of events. So, there is a need to bring out unadulterated basic facts so that readers can whet their appetite with truth. This book, Keeping up with Time, is an attempt to keep the discerning readers abreast with modern day issues, bare facts, basic analyses and unbiased opinions.

A wide variety of topical issues, articles, essays and blogs were presented in the book. Each one of these topics deals with issues where only factual and verified information was used and, as far as possible, complex issues have been dissected, simplified and explained in a clear and succinct way for the readers.

The book has been divided into three sections entitled ‘On Science and Technology’, ‘On Global Issues’, and ‘On Religion’. Each section has its own Glossary of Terms where difficult and unfamiliar terms and items have been explained, so that the topics in that section can be fully appreciated.

In the ‘On Science and Technology’ section, a wide range of technical issues of interest such as the black hole, gravitational waves, dark matter and dark energy, everything from nothing, entropy and the arrow of time etc. are presented. The most up to date information and research results have been incorporated and presented in a clear and succinct way.

In the ‘On Global Issues’ section, topics such as the inequality and inequity in capitalism, Solzhenitsyn’s views on communism, Tagore’s philosophical views, frailty in democracy, Orwellian viii dystopia, the illusion of reality, human population and many more are presented. As can be seen, some of the articles deal with historical events, while others look to the future.

In the ‘On Religion’ section, topics such as science and Islam, religion and morality, religious excesses in Islam, Einstein’s views on religion, the brutality of religious fanatics etc., are covered. In this section, views and opinions have been expressed somewhat provocatively; some readers may find that somewhat abrasive. But that was the purpose – to shake out the age-old views to bring people out of their comfort zones. But scrupulous attempts have been made to use only verified information and views.

  • Apaxmanuk is the administrator of this website.

Advanced science, Astrophysics, International, Technical

Stephen Hawking: The supernova of cosmology

In 1974, by predicting the apparently paradoxical concept of radiation emanating from black holes, Hawking reminded us that mass and energy are two sides of the same coin.

Stephen-Hawking5

We humans are a recent phenomenon in the Universe that is very old, mostly imperceptible and beyond our comprehension. Had it not been for great scientists like Isaac Newton, Albert Einstein, Edwin Hubble, Karl Schwarzschild, Subrahmanyan Chandrasekhar, Stephen Hawking and many more who unlocked the enduring mysteries of the boundless Universe, it would have been a struggle for lesser mortals like us getting our bearings straightened about our place in the cosmos. Their ground-breaking work, forever, changed our view of the “heavens.”

Postulated in 1687, Newton’s law of gravity was a beautiful synthesis between terrestrial and celestial phenomenon, reaching across the vast expanse of the Universe. It allows us to study the waltzing motion of the planets, moons, stars and other objects in the sky with clockwork precision.

Einstein’s special relativity, published in 1905, tells us that time is not only elastic, it is also the fourth component of the spacetime fabric of the Universe. Ten years later, his general relativity redefined gravity as matter’s response to the curving of spacetime caused by surrounding massive objects.

In 1916, Schwarzschild found that the solution of Einstein’s general relativity equations characterized something that confounds common sense ‒ an unfathomable hole drilled in the superstructure of the Universe. Today, we call this voracious gravitational sinkhole a black hole, a single point of zero volume and infinite density.

Much to Einstein’s consternation, in 1929, Hubble discovered that the Universe is expanding in size. His “constant” enabled us to estimate the age of the Universe. In 1930, Chandrasekhar’s calculations indicated that when a massive star runs out of fuel, it would blow itself apart in a spectacular but violent explosion and then collapse into a black hole.

Black holes were discovered in 1971, when astronomers detected a hint of radio wave emissions coming from an object in the constellation Cygnus. The emissions were later interpreted as the fingerprint of the black hole Cygnus X-1. Since then, numerous black holes, including supermassive ones, have been detected in our own Galaxy ‒ The Milky Way, and elsewhere in the Universe. According to NASA, supermassive black holes are growing faster than the rate at which stars are being formed in their galaxies.

Cloaked behind the event horizon, which is not a physical barrier but just an information barrier, it must seem that there is no way of getting mass from the black hole back out into outer space. No way, that is, not until the British physicist Stephen Hawking, arguably one of the greatest minds in scientific history, joined the Big League of Cosmology in the mid-twentieth century. With his seminal contributions to the fields of astrophysics, general relativity, quantum gravity and black holes, he raised the field of cosmology from a niche topic to a well-developed subject in the forefront of science.

In 1974, by predicting the apparently paradoxical concept of radiation emanating from black holes, Hawking reminded us that mass and energy are two sides of the same coin. He was able to show that a black hole, like any other body whose temperature is not absolute zero, emits energy in the form of radiation, energy now known as Hawking Radiation.

The continual emission of radiation causes the black hole to shrink in mass. In other words, black holes “evaporate,” although the time it takes for a solar-mass black hole to evaporate completely is immensely long ‒ vastly larger than the age of the Universe, which is 13.7 billion years. The implications are nonetheless important ‒ even black holes evolve and die.

One of the Gordian knots of cosmology is the missing mass of the Universe. There is irrefutable evidence that visible matter accounts for only four percent of the Universe’s mass. The remaining 96 percent is invisible of which 73 percent is attributed to a pervasive “dark energy,” believed to be manifestation of an extremely powerful repulsive force that is causing the expansion of the Universe to accelerate. The additional 23 percent is thought to be dark matter whose origin obviously is the many black holes spread throughout the cosmos. However, their total mass does not add up to account for all the dark matter.

To address this issue, in 1971, Hawking advanced the idea that in the intergalactic space, there may be “mini” black holes with very small masses ‒ much smaller than the mass of the Earth ‒ yet numerous enough to account for most of the unaccounted dark matter. He hypothesized that they may have been formed during the first instants of chaos following the Big Bang when matter existed in a hot, soupy plasma. Since mini black holes have not been detected so far, Hawking lamented: “This is a pity, because if they had, I would have got a Nobel Prize.”

During the 1980s, Hawking devoted much of his time contributing to the theory of cosmic inflation ‒ the expansion of the Universe at an exponential pace before settling down to expand at a slower pace. In particular, he demonstrated how minuscule variations in the distribution of matter during this period of expansion, known as the Planck era, helped shape the spread of galaxies in the Universe.

As noted above, the core remnant of a high-mass star would eventually collapse all the way to a point ‒ a so-called singularity. Having said that, singularities are places where laws of physics break down. Consequently, some very strange things may occur near them. As suggested by Hawking, these strange things could be, for instance, gateway to other universes, or time travel, but none has been proved, and certainly none has been observed. These suggestions cause serious problems for many of our cherished laws of physics, including causality ‒ the idea that cause should precede the effect, which runs into immediate problem if time travel is possible ‒ and energy conservation, which is violated if matter can hop from one universe to another through a black hole.

While scientists know Hawking for his work on cosmology, millions of others know him because of his book “A Brief History of Time.” His lucid explanation of the mechanism leading to the creation of the Universe, our place in it, how we got there, where did space and time come from, and where we might be going made the notoriously difficult subject of cosmology more understandable to the layperson.
In a follow-up book titled “The Grand Design,” Hawking outlines his consuming quest for the long-dreamed-of “Theory of Everything,” the quantum theory of gravity. Such a theory would unify the two pillars of twentieth century physics, general relativity and quantum theory.

Known as the M-Theory (M stands for Mother-of-All), it would enable us to understand all phenomena in space-time, especially the first split second of cosmic creation, when everything was unimaginably small and densely packed.

Hawking was about as pure an atheist as one can be. He dismissed the existence of an omnipotent by noting that “regularities in the motion of astronomical bodies such as the sun, the moon, and the planets suggested that they were governed by fixed laws rather than being subjected to the arbitrary whims of gods and demons.” Nevertheless, in December 2016, he had a surprising but cordial encounter with Pope Francis at a convention on Big Bang in Rome.

Besides being a genius, Hawking’s celebrity status derives from his spunk in the face of physical adversity. Born on 8 January 1942 in Oxford, England, Hawking was diagnosed with a debilitating, incurable neuromuscular disorder, commonly known as motor neurone disease (MND), when he was just 21 years old. Although doctors predicted that he has only two more years to live, he lived another 55 years and died on 14 March, 2018. There are some interesting anecdotal coincidences. Hawking was born on the 300th anniversary of Galileo’s death and died on the 139th anniversary of Einstein’s birth. Following his cremation, his ashes will be interred on 15th June 2018 in Westminster Abbey’s nave, next to the grave of Isaac Newton and close to Charles Darwin.

Instead of ruing about his mortality, Hawking considered his illness as a blessing, allowing him, in his own words, “to focus more resolutely on what he could do with his life.” Indeed, with a crumpled, voiceless body ensconced in a wheelchair, he soared and established an exalted scientific reputation as the most recognizable scientist of the modern era. The name of this supernova of cosmology will be engraved in the sands of time as long as humanity lives.

The writer, Quamrul Haider, is a Professor of Physics at Fordham University, New York

 

Astrophysics, International, Technical

Chandrasekhar and Eddington

David-and-Goliath[1]

Around 1020 BC, a shepherd boy named David took on the mighty Goliath and felled him with just a pebble and a sling on a battlefield in ancient Palestine. Since then, the names of David and Goliath signify battles between underdogs and giants. Now fast forward to early 20th century. The David of the scientific world is an Indian child prodigy named Subrahmanyan Chandrasekhar, an outstanding astrophysicist and a towering figure of 20th century science, who published his first scientific paper in the Proceedings of the Royal Society of London when he was just 19 years old.

Born in Lahore on October 19, 1910, Chandrasekhar studied physics at the Presidency College in Madras (now Chennai). He obtained his BSc degree in 1930, the year his paternal uncle CV Raman became the first Indian to win the Nobel Prize in Physics. Due to his stellar academic achievements, Chandrasekhar was awarded a scholarship to pursue doctoral studies at Trinity College in Cambridge, UK. Accordingly, he set sail for London in July 1930. He earned the doctorate degree in 1933.

During the long voyage to London, 19-year-old Chandrasekhar had enough time to pore over a problem that had bothered him for a long time – what happens to stars in the terminal stage of their life. On board the ship, he completed the calculations showing that the fate of a star depends on a critical mass, which is 1.4 times the solar mass.

Now known as the ‘Chandrasekhar Limit’, it is the limiting mass of white dwarfs – the end-stage of Earth-sized stars, but about 200,000 times as dense. If a star’s mass falls below the limit, it would end up in the stellar graveyard as a white dwarf. Otherwise, it would blow itself apart in a spectacular but violent supernova explosion and then collapse into a smaller – about 20 km in diameter – remnant called a neutron star, or possibly into a single massive point with no dimensions and infinite density. Indeed, this was the first prediction of what we now call a black hole – an entity from which nothing can escape, not even light.

Unfortunately, Chandrasekhar’s view was obstinately opposed by Arthur Eddington, the Goliath of astrophysics of the era, who knew about the possibility of black holes but refused to believe they could exist. And, thus, began the fight between David and Goliath of the scientific world. Eddington found Chandrasekhar’s conclusion about the fate of the stars unacceptable and launched an attack on his work, both publicly and privately.

On January 11, 1935, after Chandrasekhar presented the results of his research at a meeting of the Royal Astronomical Society in London, Eddington ridiculed the Chandrasekhar Limit as a “reductio ad absurdum”, meaning a logically absurd conclusion. He steadfastly refused to consider the idea that stars might collapse to nothing. He trashed Chandrasekhar’s theory as mere mathematical gimmick with no basis in reality.

Eddington’s arrogance and criticism devastated Chandrasekhar. He was shocked that instead of giving him credit for solving a challenging problem, Eddington was bent on destroying his work. But Chandrasekhar held his ground. In his fight to counter Eddington, he was assured by Niels Bohr, the 1922 Physics Nobel Laureate, that Eddington was patently wrong and should be ignored.

Nevertheless, the 1935 incident led Chandrasekhar to believe that an influential figure like Eddington could derail his career if he stays in Europe. He, therefore, moved to Chicago in 1937, where the University of Chicago provided him with an intellectual home – first at the Yerkes Observatory in Wisconsin and then at the physics department in the city campus, where he stayed until his death on August 21, 1995.

Two years after he moved to Chicago, Chandrasekhar and Eddington had their final squaring off in Paris. Undeterred in his conviction that there must be a law of nature “to prevent a star from behaving in this absurd way,” Eddington claimed that there was no experimental test that could lend support to Chandrasekhar’s theory. Nonetheless, he apologised to Chandrasekhar for questioning his calculation. “I am sorry if I hurt you,” Eddington said. When Chandrasekhar asked Eddington whether he had changed his mind, he retorted, “No.” Chandrasekhar then replied, “What are you sorry about then?” and walked away.

Although late in life Chandrasekhar and Eddington exchanged some cordial letters, they never discussed the issues concerning the fate of the stars. He eventually made peace with Eddington, who promoted his election to the Royal Society in 1944. Eddington died on November 22, 1944.

The eulogy Chandrasekhar gave for Eddington at the University of Chicago says it all about his graciousness and magnanimity. “I believe that anyone who has known Eddington will agree that he was a man of the highest integrity and character. I do not believe for example, that he ever thought harshly of anyone,” he said.

Thirty-one years after the infamous encounter with Eddington, physicists finally acknowledged the relevance and importance of the Chandrasekhar Limit. Moreover, in 1971, the first black hole was discovered. And as a tribute to Chandrasekhar’s contribution to astrophysics, NASA named one of its space-based observatories after him – the Chandra X-ray Observatory, specially designed to detect stars spiralling into black holes. Since its launch on July 23, 1999, this flagship observatory of NASA has not only discovered numerous black holes, quasars and supernovas, but also allowed us to look at a side of the cosmos that is invisible to the human eye.

Chandrasekhar’s ultimate vindication was the Nobel Prize in Physics awarded to him in 1983 for his ground-breaking work on the structure and evolution of stars. In 1984, he received the Royal Society’s highest award, the Copley Medal.

The writer, Quamrul Haider, is a Professor of Physics at Fordham University, New York.