Posts Tagged ‘gravity’

So Kate and Will have chosen Westminster Abbey for their wedding on April 29, 2011. Among their wedding guests will be some of the greatest lights of British science who are buried in the Nave. The guest list includes Sir Isaac Newton, Ernest Rutherford, JJ Thompson, Lord Kelvin and Charles Darwin.

There could be some drama at the reception if Newton and Darwin get to arguing about religion and science. Newton was a devout biblical literalist who computed the age of the universe as being 6000 years by measuring the “begats” in Genesis. Darwin, on the other hand, gave us the scientific theory of evolution that is still upsetting people of Newton’s religious temperament today.

Sir Isaac Newton, 1689

Sir Isaac Newton, 1689

Since the bride and bridegroom majored in art history in college, they might be more interested in their guests in Poet’s Corner, where Tennyson, Dickens and Chaucer share a cozy nook with Rudyard Kipling and Laurence Olivier.

The Brontë sisters are only commemorated, not buried, in the Abbey, as are Lord Byron, Oscar Wilde, Shakespeare, Jane Austen, and Paul Dirac.

Dirac was well known for his verbal brevity. One apocryphal story learned by every physics graduate student at some time in their education has a student raising his hand during a lecture, complaining that he didn’t understand what Dirac had just said. Dirac replied with a brief, “Yes,” and moved one.

But what Dirac doesn’t contribute to the conversation will be more than made up by Oscar Wilde, who is likely to have guests in stitches with his wry social banter, even though he’s been out of circulation since he died 110 years ago.

Get well soon Stephen Hawking

Me in Woody Creek

Me in Woody Creek

There’s a photograph buried in my closet that was taken in the old days of analog photography and has never been digitized and hopefully never shall be. It shows a much younger me reclining on the sand at Club Med in Marbella, topless, as is the norm in such places, holding in front of me a copy of “The large scale structure of space-time” by S.W. Hawking and G.F.R. Ellis.

The sublime Mediterranean sunshine, the water skiing lessons over the glittering waves, the entwined aromas of salt air and freshly caught fish sizzling on the grill — it all went away for an hour or so while I took a swim in Chapter 4 — The Physical Significance of Curvature.

This is an extremely sexy chapter, and not just because curves are sexy. What’s especially sexy about this chapter is the way it begins with the simple idea of the spacetime paths of massive and massless objects, and ends up laying out the basic mathematical conditions for spacetime singularities and time travel.

Now how does this happen? The key to all this is known as Raychaudhuri’s equation, discovered independently by Indian physicist Amal Kumar Raychaudhuri and Soviet physicist Lev Davidovich Landau. This fantastic equation, also known as the focusing equation, tells us when the spacetime curvature of a given gravitational system will force light cones to collapse and form spacetime singularities and when the curvature will keep them from converging, allowing conditions to develop where time travel is at least theoretically possible.

Time travel, water skiing and grilled fish make for quite a day at the beach.

Here’s to a beautiful man and to all of his beautiful books!