Views | Time waits for no one — really - Livemint

It's very rare when scientists conduct an experiment and are so astonished by the results that they themselves don't want to believe them. But that's exactly what has happened with physicists at CERN (The European Organization for Nuclear Research, which operates the world's largest particle physics laboratory) discovering that their instruments were telling them that it is possible to travel faster than light. If this is true, it upends Einstein's special theory of relativity and affects the fundamental laws of physics in, well, a very fundamental way.

Also Read | 'Faster than light' may be a possibility?

CERN scientists fired neutrinos—mysterious sub-atomic particles—from Geneva, to be detected in the Gran Sasso cavern in Italy, 730 km away. The experimenters found—and they can't explain this in terms of the laws of physics as we know and accept them—that their neutrinos traveled faster than the speed of light in a vacuum. No one can even begin to imagine the consequences—it is the quantum physics equivalent of the sudden discovery that the sun after all does move round the earth, we were wrong all this while. So no physicist actually wants to believe it, including the folks at CERN. Who have said that even though, after many months of studies and cross checks, they have not found any instrumental effect that could explain the finding, they want independent measurements to fully assess the nature of the observation.

But how does it affect you or me—the layman—if the sun is moving round the earth and stuff can travel faster than light? Not very much, except that time travel now becomes a theoretical possibility.

And if it really becomes possible, it would quite simply be The End. People and governments who can lay their hands on a time machine—and naturally they would be very rich people and very powerful governments—would keep going back and trying to correct mistakes. Of course, they would try to keep the technology as closely guarded as possible, so they can have everything just the way they want it, and entire human civilization and whatever it stands for—well, it must stand for something, right?—will be ruined for, yes, all time to come. All future wars will be fought in the past, and all history would stop making any sense. But as happens with technologies, there will surely be some people and organizations (benign or fanatical)—who will crack the secret, and existence and reality will for ever be a perfectly unpredictable yo-yo. Life and death, and everything—and I mean everything —to do with life and death would lose all meaning. The idiom "he doesn't know if he is coming or going" would be the only truth in every human life, in fact, for every life form. Utter insanity will be the only normative human mental state. There will be no mind left to be boggled.

But all this won't happen. None of it. The reason involves no math, not even a vague guesstimate of the number of zeroes in the speed of light as measured in metres per second.

However, before I come to why time travel will never be possible, I can't resist mentioning the two best science fiction stories about time travel that I have ever read.

The first one involves, unsurprisingly, the first time machine ever built and the first man who volunteers to check out whether it works. So he chooses to be transported to the day Shakespeare finished writing Hamlet. He is strapped into the machine, and there are pops and buzzes and blinding flashes of light—the usual stuff you would expect when you're traveling a few centuries back—and he arrives, hale and hearty, in the study of the playwright's Stratford-on-Avon home. It's a normal enough room, with walls covered with many framed and signed photographs—Shakespeare being knighted by Queen Elizabeth I, Shakespeare shaking hands with Winston Churchill, Shakespeare with his arm round Marilyn Monroe, etc. The great man looks up as our hero materializes next to him and welcomes him as if he had been expecting him for some time. And immediately, there are more pops and buzzes and dozens of media people materialize all around, with cameras, microphones, TV cameras. They've all come from our hero's future, to record the first successful time travel ever. That is the news story, the unique moment in history, before everyone started nipping back and forth and having fun.

The second one, again unsurprisingly, involves the first time machine ever built, and, amazingly—since I've not read a word of Shakespeare in my life—involves that poor man again. A professor of English, armed with a Complete Works of Shakespeare, is the first volunteer, who intends to go to Elizabethan London, hunt Shakespeare down and lay to rest once and for the controversy about whether Shakespeare actually wrote his plays, or it was someone else. The professor arrives, goes from pub to pub, trying to find his man, and as he is standing in a lane wondering whether to give up his quest, he is mugged. His assailants find nothing on him of any value—the currency notes in his wallet are incomprehensible junk to them—and they leave him lying in the gutter, unconscious, clutching his volume of Shakespeare's works. A few minutes later, a drunk young man called Will Shakespeare emerges from a nearby pub and finds the professor and the book. He is astonished to see his own name printed on the cover of the book, and thinks it'll be a great lark to take the book, and copy out all the plays and poems and pretend that he has created them.

All right, that was just for fun. Now to the real question: why will time travel never be possible, notwithstanding neutrinos that don't give a damn for the speed limit?

The answer, stunningly beautiful in its simplicity, comes from British physicist Stephen Hawking. If time travel was possible, he said, shouldn't we already have met some people from the future?

QED.

So, whatever life-changing problems particle physicists have to deal with post the CERN results, you and I need not be bothered. At least, bothered more than we already are in our imperfect lives.