received signals from a billion years ago!

gravitational wave's formula 

in the NYTIMES: the paramount importance of science in general (and physics in particular).

While the political displays we have been treated to over the past weeks may reflect some of the worst about what it means to be human, this jiggle, discovered in an exotic physics experiment, reflects the best. Scientists overcame almost insurmountable odds to open a vast new window on the cosmos. And if history is any guide, every time we have built new eyes to observe the universe, our understanding of ourselves and our place in it has been forever altered.

the explanation is pretty good for a newspaper article:

...  each time we wave our hands around or move any matter, disturbances in the fabric of space propagate out at the speed of light, as waves travel outward when a rock is thrown into a lake. As these gravitational waves traverse space they will literally cause distances between objects alternately to decrease and increase in an oscillatory manner.

of course, this baffling fact (now that it has been tested, was it not always a fact only we didn't postulate it?) doesn't belong in the macroworld. our daily lives are not changed by this in any perceptible manner,

In the absence of alcohol, your living room doesn’t appear to shrink and grow repeatedly. But, in fact, it does. The oscillations in space caused by gravitational waves are so small that those ripples in length had never been seen.

here comes the punch:

Yet on Thursday, the Laser Interferometer Gravitational-Wave Observatory, or LIGO, announced that a signal from gravitational waves had been discovered emanating from the collision and merger of two massive black holes over a billion light-years away. How far away is that? Well, one light-year is about 5.88 trillion miles.

what if in a not-so-distant future we could actually observe the gravitational waves from BIG BANG itself? i don't doubt it.

Too often people ask, what’s the use of science like this, if it doesn’t produce faster cars or better toasters. But people rarely ask the same question about a Picasso painting or a Mozart symphony. Such pinnacles of human creativity change our perspective of our place in the universe. Science, like art, music and literature, has the capacity to amaze and excite, dazzle and bewilder. I would argue that it is that aspect of science — its cultural contribution, its humanity — that is perhaps its most important feature.

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here for the math oriented.