by Stuart Clark
He swept his arm around the room. ‘Think of the volume of this room: what does that volume actually tell us? We may think of the volume as a measure of the space in the room but if you take away the walls, the room’s volume ceases to have meaning because there is no longer a room – there are no boundaries from which to measure. So, really, the volume of this room is telling us about the placement of the walls relative to one another, and to the ceiling and floor.’
There were a few stilted nods.
‘Everything must be measured relative to something else, or it has no meaning. A tram does not travel at thirty kilometres per hour; it travels at thirty kilometres an hour relative to the surface of the Earth – which is itself orbiting through space relative to the central sun. By thinking in this way, we can gain a more accurate understanding of Nature. I know it cuts against the grain, I understand that – I do – but we must not let that prevent us from daring to think differently about these things. Thank you.’
This time there was a smattering of polite applause. In the pregnant hush that followed, the astronomer Hugo von Seeliger placed his hands on his knees and heaved himself upright.
Einstein half-expected him to pull out his gold-chained pocket watch and make a show of checking the time, just to rub in the fact that Einstein had overrun.
Seeliger’s bearlike head turned from side to side, taking in the audience. He stroked his close-cropped grey beard and sniffed loudly. For a moment it seemed as if that was the only comment he intended to make, then he announced: ‘I am the President of the Astronomische Gesellschaft and I think I speak for all members …’ Einstein pursed his lips. Such theatrics were unnecessary, but the relish on the Academy members’ faces was clear. They were expecting something memorable. Einstein made the smallest of movements to check that he still had the letter secreted in his jacket pocket. Anticipating something like this, he had picked up the note just before leaving the apartment.
Seeliger spoke with a measured delivery. ‘… when I say that I am deeply distrustful of relativity. The work of Isaac Newton has guided astronomers for centuries – and so far has not let us down. Yet, you would have us throw it all away because of a trifling error in Mercury’s orbit.’
‘Not throw it away, but I would have you recognise it for what it is: an approximation of the truth.’
The room filled with murmuring and chair-scraping. Seeliger widened his eyes as if Einstein had just blurted out a profanity.
Images of Kepler, the great German astronomer, filled Einstein’s mind as he protested. ‘We would not be standing here today discussing this if it were not for the eight arc-minutes’ discrepancy in Mars’s orbit. It allowed Kepler to discover the elliptical orbit where everyone before had assumed circular orbits for the planets. Lord Kelvin of Britain once said that all that remained – all that remained – for science was to make better and more precise measurements, as if the work by the theoreticians were complete and there was no more fundamental physics to be discovered. But I ask you …’ He swept his gaze around the room. ‘How else can science progress? It is precisely by better measurements that we will find the gateways to new knowledge and deeper understanding, because we will identify the gaps in our theories.’
That pleased the crowd. They voiced their derision for the Scot, and Einstein knew he was winning points, even if he had resorted to their nationalism.
Seeliger squared his giant chest. ‘Herr Doctor Einstein, you said in your presentation that the deflection of starlight is the most distinctive feature of your theory. Not true. Newton’s theory also predicts a deflection. There is no novelty in what you propose.’
Einstein leaned on the lectern. ‘But relativity predicts twice the deflection that Newton does. So, the path before us is clear: let us be scientists, let us measure the deflection and lay the matter to rest.’
‘A waste of time and effort. Modern hypotheses are not needed here.’ Seeliger appealed directly to the audience. ‘I have already calculated how dust in Mercury’s orbital plane can affect its motion.’
‘You suggest enough dust to block out the sun,’ said Einstein to the man’s back. ‘I know astronomers who are ready to help. All they need is backing.’
‘Astronomers, you say. Truly astronomers or merely observatory assistants?’
Einstein stood firm under the audience’s scrutiny; clearly many in the room knew this was a jibe against Freundlich.
Seeliger continued: ‘No serious astronomer will work on your ideas. They are unnecessarily complicated. We do not need to retire Newton just yet …’ He tipped his head towards the audience. ‘… even if he was an Englishman.’
The room erupted in laughter.
Einstein reached into his jacket to retrieve the letter. ‘Professor von Seeliger, you are familiar with the work of the astronomer Karl Schwarzschild, I believe?’
‘Of course, he was one of my Ph.D students.’
‘I have here a letter from him. He’s taken great interest in my work on gravitation from the outset and he’s seen my final formulation. He agrees with my calculation …’
Seeliger lifted his chin and played to the crowd once more.
‘Then perhaps it should have been our good friend Karl – a man who is even now pursuing his patriotic duty against the Russians – who should be standing before us to explain your ideas.’ Again the room erupted in laughter.
Einstein was still simmering from the insult when Planck sauntered over. The rest of the Academy were jostling out the room, eager for the sherry being served in the lobby.
‘That looked bruising,’ said Planck.
Einstein folded the letter and placed it back in his pocket. ‘No more than I should have predicted.’
‘Is it really as simple as taking the eclipse measurements?’
‘Yes,’ said Einstein emphatically. ‘I have made a clear prediction, but von Seeliger behaves like a wildcat towards Erwin.’
‘Freundlich?’
‘Yes, they try to crush him because he’s young and eager to help. They insist he works on nothing but more star charts. It’s so oldfashioned. German astronomers will be left behind if they are not careful. And the cameras, they’re still lost somewhere in Russia. Without them and Erwin, there’s no way to test relativity and prove it to them.’ He threw an angry glance at the retreating backs.
Planck’s face looked pained. ‘I’m so sorry you had to endure such a rough ride. That’s not what you deserved, even if your ideas are difficult. I still can’t grasp them.’
‘Don’t worry. Tonight was nothing compared to what I’m about to get in Switzerland.’
Planck’s face filled with curiosity.
‘I’m going to ask Mileva for a divorce.’
12
Zurich, Switzerland
Eduard squealed with delight and threw himself at his father. The uncertainty with which Mileva had opened the apartment door evaporated and she took Einstein’s coat with unnatural haste. Only Hans Albert remained apart, regarding his father with a quizzical look.
Mileva looked slim as she reached up to the coat rack. She was just half the width of Elsa, and more like Ilse. Gone was the padding that had crept on after the boys’ births, and her outline took him back to when they had first met. He had not appreciated her shape back then, just taken it for granted, and had derived more pleasure from the way her eyes smiled at him across the lecture hall, and the aphrodisiac quality of their discussions.
Mileva ushered them all to the dining-room, where a plate of scones and a pitcher of apple juice were waiting.
Movement was difficult with the smaller boy anchored to his legs, but Einstein turned it into a game, much to Eduard’s delight. Once at the table, which was crammed in next to an upright piano, Einstein could not help but notice the full butter-dish. In Berlin, the rationing was so acute that turnips had been the only things available in quantity last winter.
‘Tete, go easy,’ Mileva chided her younger son. ‘We don’t want Papa to think I
don’t feed you.’
The little boy’s cheeks were bulging like a cherub’s, and his lips glistened with butter. His eyes were as bright as Mileva’s used to be. Eduard munched away, grinning and swapping looks with his more reserved older brother.
Mileva watched them devotedly, her face soft. The resemblance to her younger self was so strong that Einstein remembered how they had danced together when the first relativity paper had been accepted. Rather than music, their laughter had provided accompaniment, and they drank until their heads spun. They had ended up on the floor together, breathing the hot scent of wine fumes over each other.
‘Albert? Your son is talking to you.’
Einstein smiled sheepishly. ‘Sorry. Please continue.’
‘Mama sets me mathematics questions and I answer them in my notebook. She marks and comments on them for me,’ said Hans Albert.
‘He’s a good mathematician,’ said Mileva. ‘He understands binomials fully.’
Einstein’s felt a pang of loss.
‘Are you not pleased?’ prompted Mileva.
‘Very pleased. Well done, Albert. You’re a bright boy, and your mother is a good teacher.’ The words sounded hollow.
‘Perhaps you and I could have a similar notebook, Papa? You could send me questions.’
‘Perhaps we could,’ he said uncertainly.
‘Your papa is very busy with his own studies.’ Mileva reached for the teapot and chivvied them to proffer their half-empty cups.
At the end of the tea the boys slid from the table, leaving Einstein and his wife alone. Now would be the right time to bring up the divorce, the first time that they had been alone since his arrival. He opened his mouth to speak but different words emerged.
‘Thank you for letting me see the boys,’ he said.
‘You’re their father,’ she said tightly.
‘It’s just that I sometimes fear for what they must think of me. Perhaps even what you must think of me.’ He watched her closely.
She folded the napkins from the table. ‘They miss you.’
‘I know.’ Suddenly desperate for escape, he said, ‘I wondered if I may take Albert out this afternoon. I’ve arranged to show him an experiment at the university.’
It was not a lie; he had written to his old colleagues but he had expected to visit tomorrow, once the divorce business was cleared up. Now he had to get away and think. He could not look into Mileva’s dark eyes any more.
She beamed at him. ‘I’m sure he would love that. Albert?’ she called.
The boy padded down the stone steps behind his father, their descent illuminated only by the dim lightbulbs that hung like bunting from the walls. The boy’s footfalls grew uncertain and began to drop behind. ‘Papa?’
Einstein turned and smiled; the university’s basement did have a certain dungeon-like quality to it. ‘Don’t be afraid. We’re lucky my friends have let me bring you here. I want to show you something wonderful about the universe.’
‘Down here?’
‘The equipment must be isolated from vibrations and disturbances. Down here is the best place. Come.’
Hans Albert resumed his descent. When he moved it was as if the length of his limbs was taking him by surprise. It was clear that his body was preparing to change into a man’s. His face had developed, and his mother’s blunt nose and soulful eyes had taken shape, but the emergence of such adult features seemed premature to Einstein; the boy was not yet twelve.
‘Why are you looking at me like that?’ asked Hans Albert.
‘I was thinking about how handsome you are going to be when you’re a man.’
Hans Albert shrugged off the comment as just another daft thing adults say.
In the basement the air was clammy and laced with a faint metallic tang. There was a single working light dangling from the poorly plastered ceiling, throwing out just enough illumination to reveal a wide metal tank, on top of which was a platform of mirrors and cylinders.
Einstein poked around between the cables and switches on a power board in the corner of the room and a faint hum rose into the air. The upright cylinder on the platform began to emit a perfect orange light through a small window set into it.
‘Is that water?’ Hans Albert reached towards the tank.
‘Don’t! It’s mercury. Poisonous. The apparatus floats on it;
helps to isolate it and allows it to rotate smoothly.’
Einstein stepped closer and placed his fingers on the board holding the apparatus. It glided round under his touch. He brought it to a stop and then crouched to look through another cylinder, this one on its side.
‘This is a small telescope,’ he explained before turning a small screw near one of the mirrors. Back and forth he went, making minute adjustments and checking his progress through the telescope. When he was satisfied he beckoned his son. ‘Now, look through here and tell me what you see.’
Hans Albert stooped and peered. ‘It’s a pattern, rings of orange light.’
‘Very good, very good. It’s an interference pattern, produced when the two beams of sodium light are brought together and combined. That mirror in the middle of the bench is not a perfect mirror, it lets half the light through and deflects the other half off at right angles. So, it splits the light into two beams that follow different paths. Then it combines them again and feeds them into the telescope. Now! Here’s the crucial part.’
He rotated the apparatus with his finger so that it turned through perhaps an eighth of a circle. ‘Look again.’
Hans Albert repositioned himself. ‘It looks just the same.’
‘Exactly! No change whatsoever. Never disbelieve your eyes, son; science is nothing more than common sense and this …’ He pointed to the experiment. ‘… is the most important observation for the last two centuries, because no change in the pattern means that the speed of light never changes. No matter how fast you’re moving, the speed of light is always the same. It’s the only thing in the whole universe that behaves like that. If two trains collide,
each travelling at fifty kilometres per hour, they hit with a combined speed of a hundred kilometres an hour, but light is different. No matter how fast you’re going, when you measure its speed, it’s always the same.’
‘But I’m not moving, I’m standing still.’
Einstein chuckled. ‘The Earth is moving in its orbit around the sun. Don’t tell me Galileo went through all of that with the Inquisition for nothing.’ He ruffled the boy’s hair to show he was joking. ‘When we moved the equipment around, we changed the ways the rays move with respect to the Earth’s motion, and still the pattern stayed the same.’
Hans Albert’s face creased. ‘I think I understand.’
Einstein stepped closer to his son. ‘This is the experiment that I used for my first paper on relative motion. The one I wrote when you were just a year old.’
‘When you lived with us.’
Einstein had not intended to stumble on to such delicate ground. ‘I love your little letters to me,’ he said. ‘I sometimes fear that you no longer wish to write to me.’
The answer was not what he had hoped for.
‘I do get angry with you at times, Papa. Eduard sometimes dreams that you are with us. He says he can hardly remember you being at home.’
‘But I’ll visit when I can. Look at me, I’m here now. I’m not a ghost.’
‘Why do you send Mama such nasty letters?’
‘What does she tell you about my letters?’
‘Nothing,’ said the boy defensively, ‘but I hear her crying at night after they arrive. Why must you be so horrid to her?’
Silence reigned. When Einstein spoke, it was in a deliberately soft tone. ‘When I’m alone, working in my flat – you remember my desk, don’t you, you can picture me there? – I think of what I’m doing as being for you. I do it because I love you. We can all share in it.’
The boy looked confused.
‘Yes,’ said Einstein, ‘it’s my devotion to yo
u that drives me to work harder, to show you what I’m capable of doing.’
‘For Mama, too?’ There was a crippling note of optimism in the boy’s voice.
Einstein dropped his gaze, as if the words he needed were strewn across the flagstones. ‘Son … Look, I can confide in you. You’re almost an adult now; we have a bond, a relationship deeper than … Well, we don’t need your Mama to be part of what we have. We’re father and son.’
‘But she talks about when you return and we are a family again.’ A rage erupted from Einstein. He kicked the tank, setting it ringing. Hans Albert jumped in alarm.
The sight brought Einstein to his senses. ‘That will never happen. It’s impossible.’
‘It’s not impossible!’ shouted Hans Albert, tears beginning to flow. ‘Only you make it impossible.’ The boy turned and fled for the steep staircase, arms pistoning up and down. ‘ I don’t want to see you again.’
‘Wait!’ called Einstein.
Mileva sensed the tension between them the minute she saw them. ‘Something wrong?’ she asked.
‘No,’ they said in unison.
So there is a bond, thought Einstein, he does understand.
Hans Albert disappeared to his room and Mileva led Einstein to the sitting-room. The place was comfortably untidy. His eyes stopped at their wedding picture, displayed on the dust-flecked mantelpiece as if it still held currency.
Mileva saw him looking, but before either of them could say anything a delicate melody of piano notes filled the air. Einstein looked towards the sound.
‘It’s Tete,’ she whispered.
‘I thought it was Albert who played.’
‘He does, but Tete’s overtaking him already. It’s hard to tear him away from it these days.’
Einstein tiptoed to the doorway. Even though he was overwhelmed by the size of the instrument, the six-year-old radiated control. Now and then his eyes would flutter and his head would glide in some movement that mirrored the passage he was playing. There was a vivid clarity in his simple technique, no stumbling across the keys, and every note was given appropriate weight.