Einstein and the Biblical Wisdom of Questions

EinsteinQuestionsLonger2Einstein has had a good month, all things considered. His century-old prediction, that the very fabric of space and time can support waves travelling at light-speed, was confirmed by the LIGO collaboration.  More, the bizarre and horrifying consequences of his theory of gravity, the singularly-collapsed stars that came to be called ‘black holes’ have been directly detected for the first time.  As is now widely known (but how could anyone actually conceptualise the monstrous event?), it was the mutual circling and merger of two black holes that set the gravitational ripples on their billion light-year journey across the ocean of space towards the shores of our solar system.

The events have reminded us of the powerful sense of inspiration that comes from contemplating any of Einstein’s scientific achievements. He showed how to interpret the ‘Brownian motion’ of particulate matter as a conceptual window into the molecular world, once it is understood as the random buffeting of tiny but visible particles from invisible molecules. He re-imagined light as a gas of massless particles, and in doing so opened up

EinsteinGravity

Einstein thought of gravity as a curvature of space (and time) generated by mass

a path to the quantum world of the atom.  He day-dreamed as a teenager about trying to catch a light-beam, a journey of the mind that led him to the universal constant of the speed of light, and to the mutual, relativistic, inter-conversion of space and time.  And of course, he wondered if gravity might better be thought of, not as a force, but as a sort of curvature in the warp and weft of space and time.

What glories indeed! But surprisingly, he never thought of himself as particularly gifted.  Rather he would attribute his success to the prioritisation of the question rather than the answer. ‘The important thing is not to stop questioning.’ was a frequent admonition in one form or another.  A long form of this urging of careful question-crafting attributed to him goes something like this:

‘If I had an hour to solve a problem and my life depended on the solution, I would spend the first 55 minutes determining the proper question to ask… for once I know the proper question, I could solve the problem in less than five minutes.’

‘What would I see if I caught up with light?’

‘Why cant I tell the difference between being accelerated and being pulled on by gravity?’

‘What is the source of the jiggling motion of tiny dust motes suspended in water?’

‘How can I think of light in the same way I think of matter?’

These are the questions that lead to the greatest scientific discoveries of the last century. The centrality of the creative question is true at any level of scientific endeavour.  I find myself explaining to new PhD students that, although they have got to this point by proving themselves uncommonly adept and finding the right answers, this will be of little use to them now.  They need to learn instead to craft the fruitful question.  That is the central imaginative, creative act of science.

Job Blake
From William Blake’s series of paintings depicting scenes from the Book of Job. Behemoth and Leviathan Wikimedia commons

 

Perhaps that is why I have always been entranced by the ancient long-poem of Natural Wisdom found in the Biblical ‘Book of Job’. It is usually called ‘The Lord’s Answer’, for it is the long-awaited response of Yahweh to the angry Job’s railings that he is suffering unjustly, and that the world is consequently out of joint. But ‘answer’ is in every other way an inappropriate description of the speech.  For it takes the form of a list of questions, posed to the hapless Job, but directed outwards into the manifold mysteries of the natural world.  Here are just a few of the 160 or so:

Who cuts a channel for the torrent of rain, a path for the thunderbolt,

Where is the realm where heat is created, which the sirocco spreads across the earth?

Can you bind the cluster of the Pleiades, or loose Orion’s belt?

Can you send lightning bolts on their way, and have them report to you, ‘Ready!’?

Is it by your understanding that the hawk takes flight, and spreads its wings toward the south?

A poem, with each verse a question, each trope probing its own domain of creation: the winds and weather, the sky and stars, the animal world. They are highly potent questions – the containment of flood and lightening is asking about the balance of chaos and order.  The binding of the Pleiades (a tight star-cluster of associated young stars much closer than those of Orion) is motivated by curiosity aroused by observation.  There is indeed a reason that they are closely-grouped.  The pattern of avian navigation holds puzzles for us still, although we know that birds also can register patterns in the stars.  I have often suggested to scientist colleagues that they read through the Lords’ Answer to Job.  Uniformly they respond with recognition that here lies a fundamental human motivation to look deeply into nature that we also share.

In some ways, Faith and Wisdom in Science is an extended scientist’s commentary on the Book of Job. That we would have been called ‘natural philosophers’ two centuries ago, rather than ‘scientists’, is a clue that the story of science begins in the ancient thought-world of ‘wisdom’.  Certainly one of its most luminous themes – the celebration of the creative question – has not dimmed.  Einstein would have approved, but can we, in turn, succeed in passing on the love of the question, including the unanswered question, to our children?

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Faith, Wisdom and Gravitational Waves

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Thursday this week saw a wonderful gift from a large international team of scientists and engineers to the rest of humankind.  They reported the first detection of gravitational waves following their prediction by Albert Einstein a century before (in Einstein, A., Annalen der Physik 49, 769-822 (1916)] .

The discovery is the first-fruits of overwhelming human imagination, to conceive of such a thing as a wave that travels in the warp and weft of space and time itself, of the extraordinary talent, skill and care taken in building the exquisitely sensitive LIGO detectors, and of the deeply impressive patience, over decades, of researchers willing to devote fruitless decades to the long search in the hope that it will one day open our gravitational ‘ears’ to the sounds of the universe.

The astounding work deserves to be shared and enjoyed widely, and the scientists and science journalists have done an excellent job in trying to do so.  Even so several people have asked me, quite baffled, to explain what has happened.  I have found that the analogy of ripples on a lake works well:

ripples

Ripples from a splash in a lake take a while to reach the toy boat at your feet, like the gravitational waves from the black holes.

Imagine that you are standing on the shore of a calm lake.  You have a small toy boat with you that you set afloat at your feet. Then you find the largest stone within reach and heft it away into the lake.  On landing and sinking it creates a large splash a few metres away from you.  Then ripples start to spread out in circles from the entry point, widening and weakening as they travel.  After a few moments, the toy boat at your feet is disturbed by the ripples as they arrive at the shore, and very gently starts bobbing up and down.  The splash is the equivalent of the merging black holes, the surface of the lake behaves like the space between the Earth and the distant galaxy where the black holes dwell, the ripples model the gravitational waves, and the toy boat corresponds to the sensitive laser-beam detectors, which also were caused to ‘bob’ by tiny amounts as the waves passed by.

 

If you understand that, then you have understood everything about the LIGO discovery, apart from the details of the particular space-time geometries of the gravitational waves, and some rather different numbers.  The splash was not metres away but 1.3 billion light years, in a galaxy far, far away.  We know that very simply from being able, thanks to Einstein, to work out how much energy was released at the source, and therefore how far away it must have been to produce the signal strength observed here on Earth.  The wave speed was not a few metres a second, but the speed of light, fast enough to circle the earth 7 times a second.  The detector bob was not a few millimetres, but one thousandth of the diameter of a single proton.  The sheer sensitivity achieved by the experimentalists to achieve that measurement is perhaps the most impressive aspect of the whole work.

The opportunity to enjoy, celebrate and contemplate this beauty is an opportunity I looked forward to in Faith and Wisdom in Science (which, coincidentally, appeared in paperback this week).  The story embodies many of the aspects of the cultural narrative of science that I advance there: the long human story of looking into nature and seeing with our minds into its hidden structure, the experience of pain and longing in the often painful process of gaining wisdom about nature, the extraordinary human ability to do this – to reconceive of cosmic structure almost as if we were creating a universe, the experience of the joy of a sort of reconciliation when we do it, the faith in the rationality of the universe and our continuing ability to understand it.  I cannot think of a better example to illustrate how science ought to be thought of as a humanity, rather than in some form of opposition to the disciplines of language, art and poetry.  I found myself writing this brief facebook post on the day itself:

This beautiful discovery is utter human joy. The last time we saw such a wonder was in 1888. Heinrich Hertz detected waves of the electromagnetic field predicted by James Clerk Maxwell’s field equations of electromagnetism in 1865. Einstein wrote the field equations of gravity in 1915. They have wavelike solutions. It took 100 years to see them. The last 40 or so required men and women to dedicate fruitless decades to this beautiful idea. Today their gift is inestimable. It is a sort of poetry – wild imaginative force that entertains the dance of death between black holes of immense proportion, constrained by the tight form of space time curvature and the displacement of a thousandth part of a proton. Yet we noticed just that. The contemplation of all this is a gift. Thank you my patient, loving, enduring, believing fellow scientists.

There are still some glimmers of hope that there are still human activities that have not entirely been monetarised in our Western society.  There is hope that there may be more if we can learn to draw from the ancient resources of Wisdom thinking for today.  A celebration of ‘natural philosophy’ – of ‘the love of wisdom to do with natural things’ that is the real name for ‘science’ – as a deeply human activity, and a necessary part of our individual humanity, has been enriched this week.

Finally, here are the actual signals detected at the two sites, showing the rapidly increasing and quickening oscillations as the two giant black holes circle each other and merge into silence.  Superimposed on the data are the calculations from Einstein’s equations for general relativity, supposing just this scenario.  The ‘chirp’ song could not be clearer.  Not only have we seen gravitational waves for the first time, but also made the first direct detection of a black hole (in fact of course a pair of them).

ligodata

The original paper in Physical Review Letters is open-access, very readable, and here. What a gift!

The Lord brought me forth as the first of his works,[c][d]
    before his deeds of old;
23 I was formed long ages ago,
    at the very beginning, when the world came to be.
24 When there were no watery depths, I was given birth,
    when there were no springs overflowing with water;
25 before the mountains were settled in place,
    before the hills, I was given birth,
26 before he made the world or its fields
    or any of the dust of the earth.
27 I was there when he set the heavens in place,
    when he marked out the horizon on the face of the deep,
28 when he established the clouds above
    and fixed securely the fountains of the deep,
29 when he gave the sea its boundary
    so the waters would not overstep his command,
and when he marked out the foundations of the earth.
30     Then I was constantly[e] at his side.
I was filled with delight day after day,
    rejoicing always in his presence,
31 rejoicing in his whole world
    and delighting in mankind.

Hymn of Wisdom from Proverbs chapter 8