///////////////////WATER SEEN IN GHSH HS YDAY
//////////////////JANAMBHOOMI-KARAMBHOOMI
//////////////////REDUCING ENTIRE LF INTO FEW PACKING BOXES
////////////////////In Chinese the word "crisis" contains two symbols, danger & opportunity... How do you choose to deal with "crisis"? -- Jim Maclaren
CRSS=DO
///////////////////////WHERE DOES TIME GO
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Where Does the Time Go? Forward, Physics Shows
By Malcolm W. Browne, New York Times
December 22, 1998
In Lewis Carroll's mirror world of "Through the Looking Glass," it seems perfectly logical that the White Queen, who lives backward, first bandages her finger, then begins to bleed, then screams, and finally pricks her finger. On paper, if not in real life, the physics governing many natural phenomena permit time to run either forward, like a swimmer jumping from a diving board, or backward, like a reversed movie in which the swimmer leaps from the water and lands on the board.
But since a landmark experiment in 1964 by Dr. James W. Cronin and Dr. Val L. Fitch, both at Princeton University at the time, physicists have known that time reversal is not so neat in the microscopic world of particles. They found indirect but convincing evidence that sometimes a particle going backward in time fails to land on the metaphorical diving board; in other words, time, they found, could not be perfectly symmetrical.
Experimenters have now achieved direct confirmation of this unsettling inference.
To no one's surprise, physicists at two big particle accelerators, one in Switzerland and the other in Illinois, proved that when certain particles go backward in time, their behavior is somewhat different from what it is when they go forward.
If this sounds baffling to non-scientists, they are not alone; a member of the Nobel committee who sat on the panel that awarded Dr. Cronin and Dr. Fitch the 1980 prize in physics remarked, "It would take a new Einstein to say what it means."
But one important implication stands out Time's slippery nature may explain why there was anything left after the Big Bang to build the universe as we know it. Theorists have concluded that there was a slight imbalance in the amounts of matter and antimatter created at the birth of the universe. The matter and antimatter believed to have been created by the Big Bang presumably annihilated each other quickly, leaving only a slight excess of matter - just enough to create today's matter universe.
Time, which had a role in this, is probably the deepest of all enigmas in physics.
At the everyday level, physicists believe that the "arrow" of time points always in the direction of increasing disorder (or "entropy").
Natural processes run down, order yields to disorder, information disappears, and people grow old, die and decay. These processes mark the forward passage of time.
But a particle is not like a human being, and when physicists speak of a particle going backward in time, they do not mean that the particle is a tiny time machine capable of exploring the past.
A leading particle theorist, Dr. Chris Quigg of the Fermi National Accelerator Laboratory in Batavia, Ill. explained: "It's not that antiparticles in my laboratory are actually moving backward in time. What's really meant by that is that if I think of a particle moving from one place to another forward in time, the physical process is the same as it would be if we image running the film backward and also changing the particle into an antiparticle."
Three fundamental transformations of particles are involved in all this: the reversal of electrical charge (C), which changes particles into antiparticles and vice versa; parity reversal (P), the mirror reversal of every dimension in a particle (turning it inside out, so to speak), and time reversal (T).
Physicists feel comfortable when things can be explained by balance sheets that show everything accounted for. They once believed that the symmetry of parity - the original form versus its inside-out version- was inviolate, meaning that physics in a mirrow world would be identical to our own. But the 1957 Nobel Prize in Physics honored Dr. Tsung-Dao Lee and Dr. Chen N. Ning Yang for discovering that the assumed symmetry of parity in particles did not exist; that when short-lived particles called K mesons (or kaons) decay, their transformations violate parity symmetry.
Many theorists expected that this asymmetry would be balanced out by another of the transformations, that of charge. Dr. Fitch and Dr. Cronin proved, however, that charge symmetry was also violated. That meant that to keep things in balance, the symmetry of time had to be violated to make up for the symmetry violations of charge and parity. In this way the total package of charge, parity and time, or C.P.T. as physicists call this combination of interlocking components, would be "conserved," preserving the ideal of a universe that fits neatly together.
"If you believe that charge, parity and time taken together must balance out," Dr Quigg said, "then if charge and parity are a little funny, and you divide them into the charge-parity-time package, then time must be a little funny, to compensate. That was predicted by theory. But the two new experiments by Fermilab and Cern, the European accelerator group, show directly that time-reversed symmetry is violated in just the direction and amount predicted by theory. Now the C.P.T. ledger book is in balance."
Both the Cern and the Fermilab experiments measured decay processes of rare particles called neutral kaons and neutral antikaons, which consist of two quarks. (Protons and neutrons, the particles that make up the nuclei of ordinary atoms, contain three quarks.)
In the Cern experiment, detectors measured the oscillations of kaons into antikaons, and vice versa, as these fleeting particles sped away from their point of origin. If time were perfectly symmetrical, the rates at which kaons and antikaons are transformed inot each other should be precisely equal. The experiment showed, however, that the rate at which antikaons (which are a form of antimatter) turn into kaons(which are normal matter) is higher than the time-reversed process in whcih kaons become antikaons.
Some similar asymmetry could help to explain the presumed excess of matter over antimatter when the universe was created
But what, if anything, does a particle moving backward in time have to do with conventional time at larger scales?
Mathematical equations governing the laws of motion, electromagnetism and many other phenomena present no difficulty with time reversal. Nor is time reversal inconsistent with particle physics, which is governed by ordinary quantum mechanics, which for all its celebrated weirdness operates within a mathematical framework of classical three-dimensional space and time. Quantum mechanics requires no special direction of time, either forward or backward.
But cosmic relationships are governed by the laws of general relativity, Einstein's theory of gravity, and these have yet to be brought into consonance with quantum mechanics - the rules for the behavior of atoms and subatomic particles. In each of these domains, time has a somewhat different meaning.
Relativity decrees that time is not an absolute quantity. Among the surprising effects of relativity are that a moving clock runs slower than a clock at rest, and that time on a mountain top runs faster than time at sea level, because gravity is stronger at sea level and gravity slows time down.
In theory, some scientist have suggest, it might be possible to travel in time using black holes, worm holes, cosmic strings or other distortions of space-time, but one of the problems with time machines is the "grandmother paradox"; if someone could go back to the past and kill his own grandmother, a paradoxical violation of the principle of causality would result. The possibility of this happening is one of the main objections to the idea of time travel, although some physicists have devised ingenious schemes for getting around the paradox.
But does a particle going backward in time pose the same kind of paradox?
Physicists think not.
Noting that the physics of ordinary experience prevents time reversal and violations of causality, Dr. Fitch said in an interview that "things in the everyday world are statistical in nature, and disorder always increases, fixing the direction of the arrow of time. But time asymmetry for particles applies to just a handful of individual particles, not to statistical aggregates."
Dr. J. Richard Gott 3d, a Princeton University cosmologist, envisions a possible universe that would be the opposite of ours in every sense.
"I can image living in a universe like ours, except that charge, parity and time are all reversed," Dr. Gott said in an interview. "Instead of expanding from the Big Bang, such a universe would be contracting toward a big crunch, with everything growing hotter."
In a recent paper in the journal Physical Review D, Dr. Gott and his colleague, Li-Xin Li, suggested that the laws of physics "may allow the universe to be its own mother."
In an antimatter, time-reversed universe, Dr. Gott said, people would remember what we call the future, (but not what we thing of as the past), and for them, the backward flow of time would seem as natural as does our sense of forward-flowing time.
But to come to terms with such things physicists need to deal with quanta - the discrete packets of energy that define the microscopic world: electrons, photons, quarks and so forth. Even empty space is believed to be quantized - subdivided into infinitesimal cells.
But so far, despite the best efforts of Albert Einstein and many other theorists, no one has been able to dissect gravity or time into their component quantum packets, if such exist.
"We're still children as far as quantum gravity is concerned," said Dr. Daniel E. Holz, a relativity theorist at the Max Planck Institute, Potsdam, Germany.
"We don't know how to quantize time," Dr. Holz said. "You can't make heads or tails of it. When you try to quantize gravity, time is what sinks you. When we understand what to do with time in quantum gravity we'll have it done. Or turn it around: When we get quantum gravity, the big revelation will be, aha! So that's the way time works!"
Dr. John A. Wheeler of Princeton University, the cosmologist and astrophysicist who coined the term "black hole" to describe ultradense objects from which light cannot escape, believes that despite the puzzles and paradoxes posed by time, a fundamental simplicity underlies it.
"It's not so much that there's something strange about time," Dr. Wheeler said in an interview. "The thing that's strange is what's going on inside time."
"We will first understand how simple the universe is when we recognize how strange it is."
///////////////////Does Time Really Exist?
Combining relativity theories with quantum physics would eliminate time
By Stefan Anitei, Science Editor
31st of July 2007, 17:56 GMT
Adjust text size:
The more advanced the science, the more difficult puzzles emerge. Now, the shortest time intervals ever have been observed.
Ferenc Krausz in his lab at the Max Planck Institute of Quantum Optics in Garching, Germany, has managed to do this by using ultraviolet laser pulses to detect the absurdly brief quantum leaps of electrons within atoms, an event lasting roughly 100 attoseconds (100 quintillionths of a second). Like a second in 300 million years.
But even so, on the Planck scale, attoseconds would be like eons. The scale would define a region where distances and intervals are so short that the concepts of time and space start to disappear.
Planck time, the smallest time unit with any physical meaning, would be 10-43 from a second, less than a trillionth of a trillionth of an attosecond. And furthermore? Tempus incognito at the limits of the current physics. But this run touches the very basics of the problem: time may not exist in physical reality. Then, what is time and why are we its slaves?
"The meaning of time has become terribly problematic in contemporary physics. The situation is so uncomfortable that by far the best thing to do is declare oneself an agnostic." said Simon Saunders, a philosopher of physics at the University of Oxford.
One hundred years ago, Einstein's theories of relativity eliminated the concept of time as a universal constant. The past, present and future would not be absolute. But these theories, aiming for gravity and the large-scale structure of the cosmos, do not match quantum physics, the realm of the tiny.
40 ago, John Wheeler, at Princeton and Bryce DeWitt, at the University of North Carolina, tried to combine them through an equation that turned the concept of time into a more confusing one.
"One finds that time just disappears from the Wheeler-DeWitt equation. It is an issue that many theorists have puzzled about. It may be that the best way to think about quantum reality is to give up the notion of time-that the fundamental description of the universe must be timeless," said Carlo Rovelli, a physicist at the University of the Mediterranean in Marseille, France.
Many physicists believe that Wheeler-DeWitt equation rather describes a timeless universe. Another strange law of physics is that time always points to the future. All the physics laws could be applied as well if time ran backward. But for the moment, time is a one-way process; it never goes in reverse, even if no laws impede it.
"The usual explanation of this is that in order to specify what happens to a system, you not only have to specify the physical laws, but you have to specify some initial or final condition." said Seth Lloyd, a quantum mechanical engineer at MIT.
"The mother of all initial conditions was the Big Bang. Physicists believe that the universe started as a very simple, extremely compact ball of energy. Although the laws of physics themselves don't provide for an arrow of time, the ongoing expansion of the universe does. As the universe expands, it becomes ever more complex and disorderly. The growing disorder-physicists call it an increase in entropy-is driven by the expansion of the universe, which may be the origin of what we think of as the ceaseless forward march of time." said Loyd.
But as Einstein showed, time is a component of the universe. Our clocks don't measure something independent of the universe.
"In fact, clocks don't really measure time at all. I recently went to the National Institute of Standards and Technology in Boulder. (NIST is the government lab that houses the atomic clock that standardizes time for the nation.) I said something like, 'Your clocks measure time very accurately.' They told me, 'Our clocks do not measure time.' I thought, Wow, that's very humble of these guys. But they said, 'No, time is defined to be what our clocks measure.' Which is true. They define the time standards for the globe: Time is defined by the number of clicks of their clocks." said Loyd.
"We say we measure time with clocks, but we see only the hands of the clocks, not time itself. And the hands of a clock are a physical variable like any other. So in a sense we cheat because what we really observe are physical variables as a function of other physical variables, but we represent that as if everything is evolving in time," said Rovelli.
"Is time a fundamental property of reality or just the macroscopic appearance of things? I would say it's only a macroscopic effect. It's something that emerges only for big things."
"Big things" would be anything above the mysterious Planck scale.
Even if physicists ever make it to join quantum theory and general relativity, space and time will be assessed by some changed quantum mechanics, in which space and time would be clearly separated and no longer smooth and continuous.
They would be made of tiny building blocks, quanta, just like light is made of photons, individual bundles of energy.
"In quantum mechanics all particles of matter and energy can also be described as waves." said Rovelli.
A peculiar trait of the waves is that they can exist in an infinite number in the same location. Quanta could be piled together in just one dimensionless point.
"Space and time in some sense melt in this picture. There is no space anymore. There are just quanta kind of living on top of one another without being immersed in a space," said Rovelli.
////////////////QUIETEN MIND-CANDLE IN THE DARK-WATCH
////////////////Volcanoes May Have Provided Sparks Of First Life (October 16, 2008) -- New research suggests that lightening and volcanoes may have sparked early life on Earth. Researchers have reanalyzed Stanley Miller's classic origin of life experiment, offering a new analysis on how the essential building blocks of life may have arisen from volcanic eruptions. ... > full story
/////////////////////MTHR GOING FR EYE SX SOON
/////////////////////The greatest oaks have been little acorns.
~Proverb, (Polish)~
////////////////////The problem of evil points out a logical contradiction in the traditional conceptions of the nature of God and the world.
Suppose we have the following four premises:
1. God is omnipotent.
2. God is omnibenevolent.
3. God is omniscient.
4. Evil exists.
We get the following contradiction. If God is omnibenevolent, then he does not want evil to exist. If God is omniscient, then he must know about all evil in the world. If God is omnipotent, then he must be capable of doing something about it. Therefore, evil should not exist. Dropping any one of those four premises would resolve the contradiction, but dropping #4 would require us to fundamentally redefine evil in some way, and dropping the other three would undermine the Christian concept of God.
As David Hume wrote, (paraphrasing Epicurus):
"Is He willing to prevent evil, but not able? Then He is impotent. Is He able, but not willing? Then He is malevolent. Is He both able and willing? Whence then is evil?"
— Dialogues Concerning Natural Religion
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