Advanced science, Astrophysics, Cultural, International, Life as it is, Religious, Technical

Isn’t black hole a black mystery?

A black hole – hitherto an invisible celestial body – was in cosmological vocabulary even before Einstein’s theory of relativity in 1915. But when the relativity theory predicted with full scientific rigour that a massive stellar body can have such a strong gravitational pull that nothing, no object, not even electromagnetic radiation such as light, can escape from it, the concept of a black hole became firmly established in scientific parlance. But it remained at that time only a mathematical curiosity, as no scientific evidence or mechanism of formation of a black hole was put forward. However, it became a realistic possibility after the detection of pulsars some decades later.   

The detection of pulsars (rotating neutron stars) by Jocelyn Bell Burnell, a research student at the University of Cambridge in 1967, gave renewed spurt to the concept of gravitational collapse and the formation of black holes. A normal star, when it comes to the end of its life due to lack of fusion fuel, collapses under its own gravity and becomes a neutron star. It may be mentioned that an atom consists of neutrons (neutral in charge) and positively charged protons and negatively charged electrons. If gravity becomes too strong, protons and electrons are pulled together to merge with each other, neutralise their charges and become neutrons and the whole star becomes a neutron star. (For the detection of neutron star, which was considered as “one of the most significant scientific achievements of the 20th century” by the Nobel Committee, her supervisor and another astronomer were awarded Nobel prize in Physics in 1974, but Jocelyn Bell was not even mentioned in the citation. However, years later, in 2018, she was awarded the Special Breakthrough Prize in Fundamental Physics. She donated the whole of the £2.3 million prize money to the Institute of Physics in the UK to help female, minority, and refugee students become physics researchers.

Not all stars eventually become neutron stars. If the mass of a star is less than 2.6 times the mass of the Sun, the gravity would not be strong enough to turn it into a neutron star. The gravitational pull in a neutron star ultimately becomes so strong that all its mass and its nearby matters are pulled to a small volume and the star becomes a black hole. A black hole can merge with another black hole to become a bigger and stronger black hole.

It is speculated that there are black holes of various sizes in most of the galaxies and in some galaxies, there are supermassive black holes at their centres. The nearest black hole from Earth is quite a few thousand light-years away; but they exert no influence on this planet. The supermassive black hole in our galaxy (the Milky Way) is about 26,000 light-years away.

Despite the name, a black hole is not all black. The gas and dust trapped around the edges of the black hole are compacted so densely and heated up so enormously that there are literally gigantic cauldrons of fire around the periphery of a black hole. The temperatures can be around billions of degrees!

The first direct visual evidence of a black hole had been produced on 10 April 2019 by a team of over 200 international experts working in a number of countries. The Event Horizon Telescope (EHT) was used to detect the existence of a colossal black hole in M87 galaxy, in the Virgo galaxy cluster. The computer simulation from data collected in the EHT is shown below. This black hole is located some 55 million light-years from the Earth and its estimated mass is 6.5 billion times that of the Sun! So, this black hole is truly a monster of a black hole.

Computer simulation of black hole from real data

Although it is a monstrous black hole, its size is quite small and it is enormously far away (520 million million million kilometres away) from Earth. To observe directly that elusive black body that far away, astronomers require a telescope with an angular resolution so sharp that it would be like spotting an apple on the surface of Moon from Earth and the aerial dish that would be required for such a detection would be around the size of Earth! Obviously, that is not possible.

Instead, the international team of experts devised a Very Long Baseline Interferometry (VLBI) technique, which involves picking up radio signals (wavelength 1.3 mm) by a network of radio telescopes scattered around the globe. The locations of these eight radio-telescopes are shown below. When radio signals from these radio-telescopes are joined up, taking into account their geographical locations, lapsed times for signal detection etc, and processed in a supercomputer, an image can gradually be built up of the bright part of the periphery of the black hole.

Locations of Event Horizon Telescopes (EHT)

The key feature of a black hole is its event horizon – the boundary at which even light cannot escape its gravitational pull. The size of the event horizon depends on the mass of the black hole. Once an object crosses the boundary of the event horizon, there is absolutely no chance of coming back. A lead astronomer from MIT working on this EHT team said, “Black hole is a one-way door out of this universe.”

The general theory of relativity also predicted that a black hole will have a “shadow” around it, which may be around three times larger than the event horizon size. This shadow is caused by gravitational bending of light by the black hole. If something gets nearer the shadow, it can possibly escape the gravitational pull of the black hole, if its speed is sufficiently high (comparable to the speed of light).

It is postulated that the “shadow” comprises a number of rings around the event horizon. The nearer a ring is to the event horizon, the more rigorous and compact it is with extreme pressure-temperature conditions. 

If, hypothetically, an unfortunate human being falls even into the outer ring of a “shadow”, he will be pulled towards the black hole initially slowly and then progressively strongly – his leg will be pulled more vigorously than his upper part and consequently, his body will be deformed into a long thin strip like a spaghetti. And when that spaghetti shape crosses the event horizon, it will be stretched so much that it will become a very thin and very long string of atoms!

Is wormhole the link between a black hole and a white hole?

The general perception of a black hole is that it is a monster vacuum cleaner where everything, even light, is sucked into it through a funnel and nothing, absolutely nothing, can come out. It absorbs enormous amount of matter and squashes them into tiny volumes. What happens to this gigantic amount of matter is a mystery, a black mystery.

There are two parallel streams of pure speculative thoughts. One is that when a black hole becomes too big – either by incessantly swallowing up matters from its surroundings or by merger with other black holes – a super-giant explosion, more like a big bang, may take place. So, a black hole may be the mother of a new big bang, a new generation of universe.

The other thought is that the funnel of a black hole is connected through a neck, called the wormhole, to a different spacetime and hence a different universe at the other end. All the materials that a black hole sucks up at the front end in this universe go through the wormhole to another reverse funnel where all the materials are spewed out into a different spacetime. That funnel is called the white hole. Thus, a black hole and a white hole is a conjugate pair – a connection between two universes!  But the question is, since there are billions of black holes in our universe, then there could be billions of corresponding wormholes and white holes and universes.

One universe is big enough or bad enough for human minds to contemplate, billions of universes will make humans go crazy.

Dr A Rahman is an author and a columnist

Advanced science, Life as it is, Technical

Quantum Formalism

Quantum mechanics came into existence at the turn of the twentieth century when many newly discovered experimental evidences could not be explained with classical mechanics. Max Planck initiated the concept of quantisation of light in 1900 to give a rational explanation of the black body radiation. Albert Einstein laid the concept of quantisation on a firm foundation in 1905 when he produced the theory of photoelectric effects and established photons as the entity of light quanta.

Since then quantum mechanics had gone from strength to strength and produced many laws, principles and theories to explain successfully the newly emerging scientific and technical problems that came up with advanced technologies. But at the same time there were some most bizarre and mind-boggling phenomena that defied intuitive logical explanation and challenged quantum principles right up to the limits. This write-up presents some of those bizarre inexplicable phenomena.

But, first of all, we need to define specifically the broad areas of quantum mechanics and differentiate it from classical mechanics. Quantum mechanics deals with extremely small entities, such as atoms, electrons, photons etc., which are commonly called quantum particles.

An atom as a whole is neutral in charge; which means that there are as many protons (positively charged) as there are electrons (negatively charged) in an atom. Hydrogen is the first element with just one proton and hence one electron; carbon is the sixth element with six protons and six electrons. There are more than 100 elements; each element has equal number of protons and electrons. These electrons are assumed to revolve round the nucleus of the atom. When an electron is dislodged from an atom, it is free to diffuse or drift along the material. When these electrons flow in large numbers through a conducting medium, we get electricity.

Now the technical question that can be posed, is an electron a particle like a miniature ball or a wave like a photon? Quantum mechanics asserts that it can be either – a wave or a particle – depending on the circumstance. In fact, one of the major planks of quantum mechanics is the wave-particle duality. Louis de Broglie in his Ph.D. dissertation in 1924 postulated that if light waves i.e. electromagnetic waves could behave like particles, then particles such as electrons could also exhibit wave properties. Indeed, they do and Louise de Broglie received a Nobel Prize in 1929 for his ground-breaking contribution of wave-particle duality.

Electromagnetic waves propagate through space like waves, as water waves do on the surface of water having crests and troughs. When two waves merge together in harmony, the crests and troughs join together and become larger (the amplitudes of two crests or two troughs add together); this is called the constructive interference. On the other have, if two waves merge in opposition i.e. in anti-phase, the crests and troughs cancel each other and there will be no ripple and that is called the destructive interference.

Double-slit experiment with a light source

If a light source is placed in front of a double-slit barrier and the light is allowed to fall on a screen behind the barrier, the constructive and destructive interferences would show as interference fringes of bright and dark bands, as shown above. So, interference fringe is a definitive proof of wave nature of light – light diffracting through the double-slits. (Of course, light can also have particulate nature, as shown in Einstein’s photoelectric effects.)

Double-slit experiment with an electron source

Now let us get back to the question of electrons. If electrons are fired from a source towards a screen and there is a double-slit barrier between the source and the screen, the screen should show the images of two slits on the screen. That is expected and perfectly normal, as the electrons are behaving like particles going through the slits and then striking the screen. Now if the slits are sufficiently narrowed down and the rest of the arrangement remains same, what is then seen on the screen is a band of bright and dark bands, as if the electrons are behaving like waves producing interference patterns! Now remembering de Broglie’s wave-particle duality, this outcome would not be too surprising or outrageous!

Now let us make an arrangement when just one electron is fired at a time and let that electron have sufficient transit time to go through the slit and reach the screen. The electron can go through either of the slits and one would expect that images of the slits would be produced on the screen, if sufficiently large number of electrons are fired. But amazingly, an interference pattern appears on the screen!

This is bizarre. Remember that just one electron was fired at a time. Even if the electron behaved like a wave, then that electron-wave would just melt away as it reached the screen. It surely could not wait on the screen for the next electron-wave to come through and interfere with it!

Now, could that be that an electron somehow goes through both the slits simultaneously to produce an interference pattern on the screen? Then what on earth is the physical mechanism to have one electron going through two slits at the same time? The other possible picture could be that half of an electron goes through one slit and the other half through the other slit and they produce the interference pattern. But then what is the mechanism of splitting an electron into two halves to make an interference pattern? The whole thing becomes surreal, but the interference pattern is real.

Then the experimenter became more curious and thought that it would be worthwhile to find out exactly which way the electrons are going? Is an electron going through both the slits simultaneously? A detector was placed very discreetly away from the path of the electrons behind one of the slits. As an electron is negatively charged, the flow of the electron would produce current and that current would produce a magnetic field. The detector that had been designed to detect the magnetic field. Thus, a detector placed behind one of the slits would not disturb the electron path and its flow.

The experiment was then conducted with the same setup, but with a detector placed discreetly behind one of the slits. What had been found on the screen? The interference pattern just disappeared completely! Yes, no bright and dark bands; only images of the slits on the screen! It is, as if, the electrons found out that they had been spied on and they decided not to behave like waves any more. Take the detector away, interference pattern return! Science becomes supernatural!

These strange behaviours of electrons were so puzzling that even more than hundred years later (since these experimental evidences) nobody could give a rational explanation. Quantum mechanics came into existence and flourished since then, but even quantum mechanics could not give any sensible explanation of the bizarre electron behaviour. But, nonetheless, quantum mechanics had produced an abstract mathematical formalism to explain this evidence.  

In quantum mechanics, particles or waves are treated wave functions (Schrodinger’s wave equation). When there are two slits, two wave functions go through and interfere and that process is called quantum superposition. That superposition of waves produces interference pattern. Even one wave function – a mathematical formalism – can go through two slits and have superposition and produce an interference pattern.

Niels Bohr, the high priest of quantum mechanics, and his group of fellow quantum physicists produced, what is known as Copenhagen Interpretation of quantum mechanics.  This Interpretation advanced the idea that sheer act of observation of quantum particles disturbed the character of electron-wave flow and that caused the waves to collapse into particles.

Quantum mechanics gives an abstract mathematical formalism of a system. It can predict quite accurately the correct outcome (such as electron fringes), but it does not or cannot give the physical picture of the path of the electron. In fact, the Copenhagen Interpretation insists that asking to know the path of the electron is superfluous and irrelevant. What is relevant is what happens when electrons reach the destination and quantum mechanics has the answer for that. That is the strength of quantum mechanics.    

  • Dr A Rahman is an author and a columnist

Cultural, Human Rights, International, Life as it is, Political, Religious

Muslims who stand up to Mullahs are no ‘Islamophobes’

On Sunday March 17, Hassan Sajwani, an active Twitterati in the United Arab Emirates (UAE) quoted a warning his country’s foreign minister Sheikh Abdullah bin Zayed Al-Nahyan had delivered to Europe at the “Tweeps Forum” in Saudi Arabia in 2017.

The UAE foreign minister had warned Europe about the rise of Islamic extremism within the continent: There will come a day when we will see far more radicals, extremists and terrorists coming from Europe because of lack of decision-making and European politicians trying to be politically correct.

Sajwani’s tweet recollecting the UAE minister’s 2017 warning turned out to be quite prophetic. The very next day, on Monday, Turkish-born gunman Gokmen Tanis brought the Dutch city of Utrecht to a halt when he fired on a tram (streetcar) killing three people and injuring three others. The Dutch prosecutors investigating the attack said, “So far a terrorist motive is being seriously taken into account. Among other things a letter found in the getaway car and the nature of the facts give rise to that,” a statement said (in Dutch), without detailing the contents of the letter.

The Utrecht killing of non-Muslims by a Turkish terror suspect cannot be seen outside the recent massacre of Muslims inside two New Zealand mosques by a white nationalist and earlier massacres carried out against Christians inside and outside churches in The Philippines and Nigeria as well as in Pakistan, Syria, Iraq and Egypt.

While the world gave 24/7 coverage to the Christchurch mosque massacre and white folks rightfully denounced one of their own sons, to embrace their Muslim citizens, there was almost no coverage of the Muslim massacre of Christians in Nigeria just a few days earlier on March 4.

Similarly, on Jan. 27, Muslim jihadis bombed a Catholic church in Jolo, Philippines, killing 20 Christians, yet this attack barely caused a ripple. No weeping politicians, no candlelit vigils and no public demonstration by Muslims in Canada denouncing the jihadi terrorists the way whites denounced a white nationalist.

In fact, Islamists in Europe and North America used the outpouring of goodwill towards Muslims to target Muslim critics of Islamism. Death threats called for eliminating me, my friend Maajid Nawaz in the U.K., Imam Muhammad Tawhidi in Australia and scores of secular Muslims were targeted.

These attacks angered Ensaf Haider, the Canadian wife of Saudi prisoner of conscience Raif Badawi. She tweeted: “Don’t be fooled by pro-Sharia Islamists in North America. They may want you to believe they are saddened by the #NewZealandMosqueAttacks, but fact is they can’t disguise the triumphant spring in their step. Now, they’ll milk sympathy and play victim while pushing their Islamist agenda.”

As the 2017 report tracking “violent Islamist extremism” found, jihadi terrorism has resulted in the deaths of 84,000 people last year. There was a total of 7,841 attacks – an average of 21 per day – in 48 countries.

These figures should alarm Prime Minister Justin Trudeau, opposition leader Andrew Scheer and the NDP’s Jagmeet Singh, but all three parroted the Islamist agenda of legitimizing the most regressive segment of Muslims in Canada while abandoning Muslims who have stood up against Sharia and the doctrine of armed Jihad.

Which begs the question: Why do Christians have the right to laugh at a Ricky Gervais take on God and Jesus, but we Muslims dare not criticize the 17-times-a-day(1) deriding of Christians and Jews that takes place in our mosques across the world?

Just as Martin Luther was no Christianophobe when he stood up to the Roman Catholic Church, Muslims who stand up to Mullahs are no “Islamophobes.”

  • The 17-times a day deriding of Christians and Jews derives from Sura Fatiha which is recited at every raqah of the prayer. Through Sura Fatiha, a Muslim asks Allah to ‘show the right path, not the path of those who earned your wrath or those who went astray’. The Quran does not say who those people are, who earned Allah’s wrath, but according to Tafseers of the Quran and Sharia Law as well as Hadith, the reference is to Jews and Christians. If the Mullahs (Imams) denounced this man-made Tafseer and Hadith as incorrect and rejected, the 17 references would turn into a positive form of prayer. But not a singe Mullah (Imam) is willing to denounce this man-made intrusion into the meaning of Surah Fatiha.

Tarek Fatah, a founder of the Muslim Canadian Congress and columnist at the Toronto Sun, is a Robert J. and Abby B. Levine Fellow at the Middle East Forum.

Economic, Environmental, International, Life as it is, Technical

Who will pull us out of the climate change conundrum?

Every year since 1995, our leaders or their representatives met at the so-called Conference of Parties, debating climate change, global warming in particular. Over time, the conferences’ goal has become what is politically possible, not what is environmentally desirable. Hence, the emphasis has shifted from reducing emissions of carbon dioxide to helping nations adapt to whatever the future climate might look like. While adaptation is necessary for survival on a planet ravaged by the vagaries of global warming, it also means throwing in the towel against the fight to tackle climate change effectively.

The outcomes of these conferences clearly indicate that we are backing away from a disaster of our own making by surrendering to the whims of powerful people beholden to lobbyists, special interest groups and climate change deniers. Who will, therefore, pull us out of the climate change conundrum, so that our future generations can stay in a climate-safe planet? How can we remain hopeful while facing the growing, irrefutable evidence of devastating climate-induced changes around us?

On March 15, 2019, hundreds of thousands of schoolchildren all over the world, from the South Pacific to the edge of the Arctic Circle, answered the above questions, loud and clear. They skipped classes to protest what they see as the failures of their governments to take tough actions against global warming. Although most of the protesters are under the voting age, they nevertheless want to have a say in the politics of climate change. Hence, they are boldly challenging the stewards of “their” planet who have the ability to make the real differences needed right now with regard to climate change.

The protest was inspired by a 16-year-old Swede, Greta Thunberg, to express children’s frustration with older generations’ laissez-faire attitude towards climate change. She kicked off a global movement after last summer’s record heat wave in northern Europe and forest fires that ravaged swathes of her country up to the Arctic. Since August 10, 2018, she has been sitting outside the Swedish parliament every Friday, now known as Fridays for Future, protesting inaction by adults. She recently gave a speech to climate negotiators in Switzerland and told them, “I want you to panic. I want you to feel the fear I feel every day. And then I want you to act.”

Fridays for Future was also observed in New York City, where students at dozens of schools across the five boroughs stayed away from their classroom and took to the streets. They hosted multiple rallies in front of the City Hall, Columbus Circle, Bronx High School for Science, Columbia University, American Museum of Natural History, and elsewhere. All of them chanted, “Money won’t matter when we’re dead.” “Sea levels are rising and so are we.” “I’m not showing up for school because adults aren’t showing up for climate.”

They spoke about the importance of schools teaching students about climate change from a young age. “If we don’t learn about it, we might believe the things that are lies, that it’s a hoax… They can’t just leave a falling apart planet to us. We only have so much time to fix it, and we have to fix it while we still can, because by the time we’re in power we can’t fix it,” said the 13-year old Rachel Entin-Bell, who was protesting at the Washington Square Park.

The star of the protest was a 9-year-old kid, Zayne Cowie, who sat in front of the City Hall with his little sister on his lap holding a sign that says “Climate Strike”. “Climate change is happening faster than we can react. Well, we could react fast enough but nobody cares,” he said. Sadly, we are living at a time when a 9-year-old is more knowledgeable about climate science than the current occupant of the White House!

Starting in December 2018, following in the footsteps of Greta, Zayne opted out of attending Friday classes at his school and instead sit in front of the City Hall—rain, snow or shine—reading from the children’s book of verse “Goodbye, Earth.” The first two stanzas are:

The World is big and I am small.

One day I wish to see it all.

Pacific islands, northern Lights,

Himalayas, desert nights.

The World is big and I am small.

The Earth’s in trouble, hear her call.

Me and my nine-year-old peers

Have now lived through its hottest years.

Indeed, when children come out on the streets to protest climate change, we know that it is high time for adults to wake up and act decisively. Unfortunately, adults are caught up in their egotistic needs of power, accumulation of wealth, comfort and socio-economic status, leaving very little time to care about future generations.

Ironically, children like Zayne, Greta, Rachel and others are the first generation who are least responsible for the 410 parts per million concentration of carbon dioxide in the atmosphere today, but will face most of the catastrophic consequences from it. They are coming of age when the window to ward off this nightmare scenario is rapidly shrinking.

Many older adults have been warning for decades that our future generations will suffer for our greed, selfishness and inertia from continued inaction. Now, those future victims are raising their voice to try and shape the agenda. They are the bastions of hope emerging around the world. Their message: No more business as usual. We need to act as though our future and the future of all life on this planet depends on what we do, because it does.

How did adults react to the protests? In New York City, 16 protesters have been arrested for blocking traffic in front of the American Museum of Natural History. They were charged for disorderly conduct. Shame on us, who are doing very little at addressing climate change, leaving the consequences to be dealt with by younger generations, yet arresting them for raising their voices against climate change.


The writer, Quamrul Haider, is a professor of physics at Fordham University, New York

Advanced science, Astrophysics, Life as it is, Technical

From Newton’s Gravitational Law to Einstein’s Gravitational waves

Visualisation of Newton’s gravitational attraction

Summer 1666, a young Cambridge University physics student by the name Isaac Newton was sitting under an apple tree in his mother’s garden at Woolsthorpe Manor in Lincolnshire, England. An apple fell from the tree on the ground and that triggered him to think: why did the apple come down straight to earth, not go sideways or upwards? That question led him to delve deeper into the mystery of attraction between two bodies and to come up with the law of gravity. He published his research work in “The Principia Mathematica” in 1687, where he described, among other things, this seminal work on the law of universal gravitation.  

This law of gravitation tells us that two bodies attract each other with a force which is proportional to the product of the masses of the bodies and inversely proportional to the square of the distance between them. This simple empirical formula was astonishingly successful in calculating the force of attraction between two bodies on earth. This law was also applied to calculate the attractive force between the earth and the moon and to the orbital motion of the moon round the earth. The law was quite accurate in defining the orbits of many other celestial bodies, although in few cases the law was somewhat inaccurate.

This law was and still is the centre piece of what is now known as the ‘classical physics’ or ‘Newtonian Physics’. We all studied this law, Newton’s laws of motion, properties of matter, electricity and magnetism, heat and thermodynamics, optics etc in our schools and they gave the grounding for advanced physics.

For nearly 300 years this law was supreme and explained how the force of gravity controls the motions of all celestial bodies. However, the law did not say anything about the nature of this force or how the force is propagated through space; it just stated that the force diffuses through space without leaving any trace. As the predictions of the law were right in most of the cases, nobody bothered too much about these minor details or even ignored some minor discrepancies.    

At the turn of the 20th century, a patent clerk by the name Albert Einstein was working on patent submissions of electrical devices in Bern, Switzerland as a ‘Technical Expert, Third Class’ and in his spare time he was working on gravitational problems. The Patent Office work took up 48 hours of his time per week over six days. Einstein described his work load subsequently as, it left him with ‘eight hours for fooling around each day and then there is also Sunday!’.

In 1905 he published a technical paper outlining the Special Theory of Relativity giving revolutionary scientific ideas and concepts. In this paper, he introduced two fundamental concepts: the principle of relativity and the constancy of speed of light. The speed of light was stated to be independent of the speed of the observer. In other words, whether the observer moves in the direction of light or opposite to it, he would see the speed of light always remaining constant (c= 3*108 m/s). (It may be mentioned that in 1905, Albert Einstein produced three more monumental papers of enormous significance: (i) the mass-energy equivalence (E=mc2), (ii) Brownian motion of small particles, and (iii) photoelectric effects. For his work on photoelectric effects showing the particulate nature of light, which laid the foundation for quantum mechanics, he was awarded Nobel prize in 1921. As mentioned above, the year 1905 was extremely productive for Albert Einstein.

Visualisation of Einstein’s spacetime construct

Einstein developed his relativity concept even further and produced the General Theory of Relativity in 1915. In this General Theory of Relativity, he advanced the principle of spacetime, not space and time. He stipulated that the three dimensions of space (such as X, Y and Z dimensions of cartesian coordinates) and one dimension of time are not independent of each other, but intricately linked to form a single four-dimensional spacetime continuum.

This concept of spacetime continuum was revolutionary at that time and even now they make human beings baffled. The relativistic consideration has produced what is now called the time dilation. The passage of time is relative and so it depends on the motion of an observer relative to a stationary observer. Also, the passage of time depends on the location in a gravitational field. For example, a clock attached to an observer in a spaceship will tick slower than that of a clock attached to an observer in a stationary position. Also, a clock in a higher gravitational field, such as at the surface of earth, will tick slower than that of a clock in lower gravitational field such as the top of a mountain.

Let’s take an example. There were three men in the UK, all of them exactly of the same age, say, 25 years. They decided to offer themselves as guinea pigs for a research on gravity. One was asked to stay in Lincolnshire, England (not too far from Newton’s famous apple tree), the other was told to go and live high up in the Himalayan mountains and the third, most adventurer of the lot, got the opportunity to have a space travel in a superfast spaceship. The spaceship travelled fast and so his clock was ticking slowly. Let’s say his spaceship was so fast that one year in the spaceship clock was equal to five earth years and the mountain man clocked 10 minutes more than the Lincolnshire man in five years. When after five years they met on earth, they found that the mountain man was 10 minutes older than 30 years, Lincolnshire man was 30 years of earth age and the spaceship man was whopping four years younger than 30 years! To the spaceship man, it would look like he had come back four years in the future!     

Einstein stipulated that the gravitational field creates space and the bodies with masses bend and warp space; more like massive bodies create curvature in a trampoline. All less massive bodies fall into the curvature in the trampoline created by the massive bodies. When there are a large number of bodies warping the space, the space becomes jagged and celestial bodies move around in tortuous paths. There is no force of gravity pulling objects towards each other; just the bodies move around the jagged curved space along the path of least resistance.

Space, like any other force field, is discreet, quantised and granular. The quantum of space is dubbed as graviton, similar to the term photon in electromagnetic field, and it is so small that we cannot feel its discreteness, as we cannot feel the discreteness of photons of light or discreteness of atoms in a solid body.

Exactly hundred years after Einstein’s General Theory of Relativity, experimental evidence of gravitational field and gravitational wave have been produced by the LIGO (Laser Interferometer Gravitational-wave Observatory) experiment and shown that space is modulated by the gravitational field. A monochromatic laser beam of light was split and sent at right angles to each other along two arms, each of 4 km long. These beams were reflected back along the same path and allowed to interfere back at source. If there is no distortion or modulation of the path lengths, the two beams would interfere in anti-phases and there would be no interference patterns.

When two super massive black holes some 1.3 billion light years away merged and produced a gigantic massive black hole, an enormous amount of energy, equal to three solar masses, was produced and sent out as gravitational energy. It rippled through the whole universe in the form of gravitational wave at the speed of light and deformed the spacetime fabric. That deformation in spacetime was detected by the LIGO experiment in the form of interference pattern and that proves that gravitational waves modulates the space. 

The implication of Einstein’s spacetime is that at the very beginning when even the ‘Big Bang’ did not take place, there was no spacetime. Spacetime came into existence following that ‘Big Bang’, when gravity came into play along with other forces such as electrical force, strong nuclear force and weak nuclear force. If at the end, as Physics predicts, the whole universe starts to collapse, there would be what is called the ‘Big Crunch’ and the spacetime would collapse too and disappear. There will be nothing, no material, no space and no time. These are the predictions of scientific theories as exist today.

In 1930 when Einstein came to London as the guest of honour at a fundraising dinner to help the East European Jews, George Bernard Shaw, the chief guest, said humourously, “Ptolemy made a universe which lasted for 1400 years. Newton made a universe which lasted for 300 years. Einstein has made a universe, and I can’t tell you how long that will last.” The audience laughed loudly, but none louder than Einstein.

  • Dr A Rahman is an author and a columnist