Stephen Hawking’s final paper was published this week. Like his last book, The Grand Design, it is about how the universe began. In 1979, he became the seventeenth Lucasian Professor of Mathematics at Cambridge University. His modest aim was to understand the universe, the whole thing, from beginning to end. He missed his mark by […]
These are exciting times. Every few months astronomy surprises us with insights into ancient secrets. New telescopes are scanning galaxies throughout the visible universe. Most galaxies are mind-bogglingly far away. Exactly how far has long been a fundamental issue. But we just got a whole new way to measure it. Today the universe is much […]
What exactly happened when the universe was born? What happened at the Big Bang? is the title of last summer’s popular science exhibition sponsored by six leading British universities and the Royal Society in London. Amid much fascinating information, the exhibition’s answer was: We don’t know. Yet, as Science Seen’s readers will recall, that answer […]
In 2015 scientists at LIGO observed a wave of gravitation—a distortion of space itself that came from two black holes colliding more than a billion light years away. LIGO is a gravity telescope of exquisite sensitivity. Its observation shaped up as the top science story of the century. In record time, this week it nailed […]
We think of space as empty. It’s not. Quite aside from stray hydrogen atoms and fleeting quantum particles in the vacuum, space is substantial. It has mass. Indeed Planck-satellite measurements now show space is three times denser than the average of the universe’s matter. Yet like the rest of us most physicists still treat space […]
Does time flow? It is a fundamental question. It has confounded physics for hundreds of years. It still does. We sense the flow of time. Today many physicists say this is an illusion. I say they don’t understand. Physics at the very largest and the very smallest scales leads to a simple way to make […]
A new cosmic contradiction is begging for an explanation. We’ve known for years that space is expanding. Now new measurements of the rate at which it is expanding seem to differ from previous ones based on the standard cosmological model. New physics often comes from measurements that don’t fit theory. Here is my take on […]
‘It is indeed an exacting requirement to have to ascribe physical reality to space in general, and especially to empty space.’ — Albert Einstein Most physicists work in a vacuum. That is, they tend to think in terms of particles in empty space. But both Albert Einstein and recent evidence say they are wrong: Far […]
There are billions of black holes in our universe. Maybe gazillions. Stephen Hawking says they give off a strange kind of radiation. So we should see them, right? Here’s a cosmological Catch-22. To set the scene, the Albert Einstein Institute says: ‘If, in our universe’s fiery youth, “mini black holes” of very little mass had […]