ED v. Mamata Banerjee Over I-PAC Raid : Live Updates From Supreme Court Hearing
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ED v. Mamata Banerjee Over I-PAC Raid : Live Updates From Supreme Court Hearing
Click below:-
https://www.livelaw.in/top-stories/ed-v-mamata-banerjee-over-i-pac-raid-live-updates-from-supreme-court-hearing-519119
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(Continued) Bryson, Bill (2010-01-22). A Short History of Nearly Everything: The bestselling popular science book of the 21st Century: Transworld: but it changed the universe from something you could hold in your hand to something at least 10,000,000,000,000,000,000,000,000 times bigger. Inflation theory explains the ripples and eddies that make our universe possible. Without it, there would be no clumps of matter and thus no stars, just drifting gas and ever-lasting darkness. According to Guth’s theory, at one ten-millionth of a trillionth of a trillionth of a trillionth of a second, gravity emerged. After another ludicrously brief interval it was joined by electromagnetism and the strong and weak nuclear forces – the stuff of physics. These were joined an instant later by shoals of elementary particles – the stuff of stuff. From nothing at all, suddenly there were swarms of photons, protons, electrons, neutrons and much else – between 1079 and 1089 of each, according to the standard Big Bang theory. Such quantities are of course ungraspable. It is enough to know that in a single cracking instant we were endowed with a universe that was vast – at least a hundred billion light years across, according to the theory, but possibly any size up to infinite – and perfectly arrayed for the creation of stars, galaxies and other complex systems. What is extraordinary from our point of view is how well it turned out for us. If the universe had formed just a tiny bit differently – if gravity were fractionally stronger or weaker, if the expansion had proceeded just a little more slowly or swiftly – then there might never have been stable elements to make you and me and the ground we stand on. Had gravity been a trifle stronger, the universe itself might have collapsed like a badly erected tent without precisely the right values to give it the necessary dimensions and density and component parts. Had it been weaker, however, nothing would have coalesced. The universe would have remained forever a dull, scattered void. This is one reason why some experts believe that there may have been many other big bangs, perhaps trillions and trillions of them, spread through the mighty span of eternity, and that the reason we exist in this particular one is that this is one that we could exist in. As Edward P. Tryon of Columbia University once put it: ‘In answer to the question of why it happened, I offer the modest proposal that our Universe is simply one of those things which happen from time to time.’ To which adds Guth: ‘Although the creation of a universe might be very unlikely, Tryon emphasized that no one had counted the failed attempts.’ Martin Rees, Britain’s Astronomer Royal, believes that there are many universes, possibly an infinite number, each with different attributes, in different combinations, and that we simply live in one that combines things in the way that allows us to exist. He makes an analogy with a very large clothing store: ‘If there is a large stock of clothing, you’re not surprised to find a suit that fits. If there are many universes, each governed by a differing set of numbers, there will be one where there is a particular set of numbers suitable to life. We are in that one.’ Rees maintains that six numbers in particular govern our universe, and that if any of these values were changed even very slightly things could not be as they are. For example, for the universe to exist as it does requires that hydrogen be converted to helium in a precise but comparatively stately manner – specifically, in a way that converts seven one-thousandths of its mass to energy. Lower that value very slightly – from 0.07 per cent to 0.06 per cent, say – and no transformation could take place: the universe would consist of hydrogen and nothing else. Raise the value very slightly – to 0.08 per cent – and bonding would be so wildly prolific that the hydrogen would long since have been exhausted. In either case, with the slightest tweaking of the numbers the universe as we know and need it would not be here.
I should say that everything is just right so far. In the long term, gravity may turn out to be a little too strong; one day it may halt the expansion of the universe and bring it collapsing in upon itself, until it crushes itself down into another singularity, possibly to start the whole process over again. On the other hand, it may be too weak, in which case the universe will keep racing away for ever until everything is so far apart that there is no chance of material interactions, so that the universe becomes a place that is very roomy, but inert and dead. The third option is that gravity is perfectly pitched – ‘critical density’ is the cosmologists’ term for it – and that it will hold the universe together at just the right dimensions to allow things to go on indefinitely. Cosmologists, in their lighter moments, sometimes call this the ‘Goldilocks effect’ – that everything is just right. (For the record, these three possible universes are known respectively as closed, open and flat.) Now, the question that has occurred to all of us at some point is: what would happen if you travelled out to the edge of the universe and, as it were, put your head through the curtains? Where would your head be if it were no longer in the universe? What would you find beyond? The answer, disappointingly, is that you can never get to the edge of the universe. That’s not because it would take too long to get there – though of course it would – but because even if you travelled outward and outward in a straight line, indefinitely and pugnaciously, you would never arrive at an outer boundary. Instead, you would come back to where you began (at which point, presumably, you would rather lose heart in the exercise and give up). The reason for this is that the universe bends, in a way we can’t adequately imagine, in conformance with Einstein’s theory of relativity (which we will get to in due course). For the moment it is enough to know that we are not adrift in some large, ever-expanding bubble. Rather, space curves, in a way that allows it to be boundless but finite. Space cannot even properly be said to be expanding because, as the physicist and Nobel laureate Steven Weinberg notes, ‘solar systems and galaxies are not expanding, and space itself is not expanding.’ Rather, the galaxies are rushing apart. It is all something of a challenge to intuition. Or, as the biologist J. B. S. Haldane once famously observed: ‘The universe is not only queerer than we suppose; it is queerer than we can suppose.’ The analogy that is usually given for explaining the curvature of space is to try to imagine someone from a universe of flat surfaces, who had never seen a sphere, being brought to Earth. No matter how far he roamed across the planet’s surface, he would never find an edge. He might eventually return to the spot where he had started, and would of course be utterly confounded to explain how that had happened. Well, we are in the same position in space as our puzzled flatlander, only we are flummoxed by a higher dimension. Just as there is no place where you can find the edge of the universe, so there is no place where you can stand at the centre and say: ‘This is where it all began. This is the centre-most point of it all.’ We are all at the centre of it all. Actually, we don’t know that for sure; we can’t prove it mathematically. Scientists just assume that we can’t really be the centre of the universe – think what that would imply – but that the phenomenon must be the same for all observers in all places. Still, we don’t actually know.
For us, the universe goes only as far as light has travelled in the billions of years since the universe was formed. This visible universe – the universe we know and can talk about– is a million million million million (that’s 1,000,000,000,000,000,000,000,000) miles across. But according to most theories the universe at large – the meta-universe, as it is sometimes called – is vastly roomier still. According to Rees, the number of light years to the edge of this larger, unseen universe would be written not ‘with ten zeroes, not even with a hundred, but with millions’. In short, there’s more space than you can imagine already without going to the trouble of trying to envision some additional beyond. For a long time the Big Bang theory had one gaping hole that troubled a lot of people – namely, that it couldn’t begin to explain how we got here. Although 98 per cent of all the matter that exists was created with the Big Bang, that matter consisted exclusively of light gases: the helium, hydrogen and lithium that we mentioned earlier. Not one particle of the heavy stuff so vital to our own being – carbon, nitrogen, oxygen and all the rest – emerged from the gaseous brew of creation. But – and here’s the troubling point – to forge these heavy elements, you need the kind of heat and energy thrown off by a Big Bang. Yet there has been only one Big Bang and it didn’t produce them. So where did they come from? Interestingly, the man who found the answer to that question was a cosmologist who heartily despised the Big Bang as a theory and coined the term Big Bang sarcastically, as a way of mocking it. We’ll get to him shortly, but before we turn to the question of how we got here, it might be worth taking a few minutes to consider just where exactly ‘here’ is. A word on scientific notation. Since very large numbers are cumbersome to write and nearly impossible to read, scientists use a shorthand involving powers (or multiples) of ten in which, for instance, 10,000,000,000 is written 1010 and 6,500,000 becomes 6.5 × 106. The principle is based very simply on multiples of ten: 10 × 10 (or 100) becomes 102; 10 × 10 × 10 (or 1,000) is 103; and so on, obviously and indefinitely. The little superscript number signifies the number of zeroes following the larger principal number. Negative notations provide essentially a mirror image, with the superscript number indicating the number of spaces to the right of the decimal point (so 10−4 means 0.0001). Though I salute the principle, it remains an amazement to me that anyone seeing ‘1.4 × 109 km3’ would see at once that that signifies 1.4 billion cubic kilometres, and no less a wonder that they would choose the former over the latter in print (especially in a book designed for the general reader, where the example was found). On the assumption that many readers are as unmathematical as I am, I will use notations sparingly, though they are occasionally unavoidable, not least in a chapter dealing with things on a cosmic scale.
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