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The Einstein File: J Edgar Hoover’s Secret War Against the World’s Most Famous Scientist

On the face of it, one would think that this book was the perfect subject for the perfect author. After some years of trying, the journalist Fred Jerome has been able to obtain the almost unredacted FBI files on Albert Einstein. One knows, if one has done this, that FBI files, when they are released, often come with lines of thick black ink that cover things the bureau thinks you should not know. These include the names of informants and FBI agents.

In my case, I wanted my own file as I was thinking of writing a piece that I was going to call “Friends and neighbors”, but the redacted file was useless. My file had been assembled because I needed a clearance to work at Los Alamos. In Einstein’s case it was because J Edgar Hoover – the then head of the FBI – had an obsessive hatred of Einstein, who, for Hoover, represented every left-wing tendency he despised.

Jerome wanted Einstein’s files because he saw they represented a marvellous story – spying on the greatest scientist of the 20th century. It should also be noted – as the author does – that Jerome’s father was jailed for being a member of the Communist Party. He does not tell us the details, but he has a vivid memory of being followed by men in grey suits wearing fedoras – FBI agents.

In short, as I said, one seems to have the perfect subject for the perfect author. But as I was reading The Einstein File, I kept asking myself why I did not like the book more. First there is the writing, which I found sloppy. For example, Jerome describes the July 1939 visit of Eugene Wigner and Leo Szilard to Einstein, who was vacationing on Long Island. Their purpose was to get Einstein to sign a letter to President Roosevelt warning of a possible German attempt to make nuclear weapons. On the way they drove past the hypermodern structures that had been erected for the World’s Fair that was being held in New York. Jerome writes (page 30): “For all that Szilard loved inventions and the benefits of technology, at that moment the glitzy exhibition must have seemed an ironic backdrop to the catastrophic drama he sensed was about to unfold.” How does Jerome know what impression these structures made on Szilard, to say nothing of their being an “ironic backdrop”? This is a trivial example, but I will give a very serious one later.

On top of this, there is the matter of the page notes. Many of the pages are festooned with stars and daggers indicating some note or notes at the bottom of the page. Not only are these notes exceedingly distracting, but also many of them seem pointless. For example, after a largely irrelevant divagation about the bubonic plague, we are informed at the bottom of page 29 that “before subsiding in 1656, the Plague killed more than 100,000 Londoners”. Unless one is Gibbon, it is better to let sleeping page notes lie.

Apart from the problems with the writing there is another problem that is really not Jerome’s fault. The book quotes extensively from the FBI files and, to put the matter bluntly, they are so stupid as to be excruciatingly dull. Apart from the absurdity of trying to show that Einstein was a spy for the former Soviet Union, one is struck again and again by how totally incompetent these people were – and, God help us, perhaps still are. In the case of Einstein they could not get even the elementary facts straight.

Considerable resources were spent investigating an imaginary son, Albert Junior, who was supposed to have some sinister connection with the Soviets. A biographical sketch of Einstein from 1950, meanwhile, contains so many basic mistakes that it appears to have been written by a child. What is not childish is its allegation that Einstein had a connection with Klaus Fuchs, who, as we know, did spy successfully for the Soviet Union.

In this respect Jerome makes such a monumental error that when I first read it I was sure that it must have been taken from one of the FBI reports. A speech writer for Senator Joseph McCarthy named Howard Rushmore had published a series of articles in the New York Journal American that claimed that Einstein had a connection with Fuchs. Hoover, and his deputy Clyde Tolson, eventually read and relied on them. Jerome comments: “Whether or not Hoover and Tolson had already read the Rushmore article, Tolson no doubt remembered that Einstein and Fuchs were both German Jews and had lived in Berlin around the same time.”

Not only is this statement totally false, it is also very dangerous. Anyone who has taken five minutes to read about Fuchs knows that he came from generations of Protestant pastors, including his father, who converted to Quakerism. Moreover, Fuchs did not live in Berlin at around the same time as Einstein. He was a student in Leipzig and then Kiel until he was forced to flee Germany in 1933. Jerome’s statement is dangerous because if you search for Fuchs on the web, you will find virulently anti-Semitic sites that claim that Fuchs was a Jew. Incidentally, when asked, Fuchs said that he had never met Einstein.

If one has studied Einstein’s life, it comes as no surprise that he took an active part in politics. One of my favourite stories told by one of his assistants was of Einstein coming into the office to announce that now Kurt Gödel had really gone crazy. He had voted for Eisenhower for president, Einstein explained.

But, to Jerome’s credit, he has put together a chronicle of Einstein’s political and social activity in the US that is valuable and, at least to me, in some parts novel. I had not realized, for example, Einstein’s involvement with racial injustice. He spoke out against lynching and he lectured at black educational institutions. He became friends with Paul Robeson, the magnificent black actor and singer, whose left-wing views put him at the top of Hoover’s list of enemies, with Einstein close by. It seems to have been Hoover’s intent to put together enough of a dossier to have Einstein deported. (To where? Germany?) It is easy to be smug about this and to say that it is all in the past. But these are difficult times and I am sure there are Hoovers out there making lists.

Atom lithography sees the light

Chip manufacturers currently make integrated circuits by shining light through a stencil or “mask” of the circuit design, passing this light through a series of lenses to reduce the size of the image, and then projecting this image onto a silicon substrate covered by a photosensitive resist. Chemicals are then used to wash away the exposed areas of the resist, leaving just the pattern of the mask on the silicon. However, the lenses do not work at short wavelengths and consequently limit the minimum feature size to about 100 nm.

Thywissen and Prentiss have overcome this problem in principle by exposing a silicon substrate to a beam of “metastable” argon atoms. These metastable atoms exist in a naturally excited state and release their energy when they strike the substrate. A layer of hydrocarbons that resides on the substrate functions as the resist by adhering more strongly to the substrate when energized.

To create a pattern in the atom beam, the researchers used a mask made of laser light. The argon atoms resonant with the light are excited into an even higher state, but they fall back down to the ground state almost instantaneously, depriving the resist of energy at the points below the mask.

In previous experiments, this mask was created by forming a standing wave from a resonant laser beam. Only atoms that passed through points of minimum intensity on the standing wave reached the resist in a metastable state. However, the resolution of this approach is fundamentally limited because the undulations in such a standing wave are equal to half the wavelength of the light.

In the latest work, the mask consists of two overlapping laser beams, one of which is made up of a number of discrete frequency components that approximately match the excitation energy of the argon atoms. The other laser beam creates a potential gradient across the atom beam, shifting the atoms into resonance at particular points in space. At these points the atoms fall to the ground state, leaving the resist unstrengthened.

“By modifying the frequency rather than the intensity of the light, the resolution of the mask is not limited by optical diffraction,” says Thywissen. “This is similar to magnetic resonance imaging, which can produce images whose resolution is much smaller than wavelength of radiation used.”

Thywissen and Prentiss’ technique produced features with a minimum width of about 900 nm, still two orders of magnitude larger than the smallest so far achieved using atom lithography. However, since the new technique is not diffraction limited, it could in the future generate smaller features than other atom-based systems.

“Atom lithography has long demonstrated feature sizes smaller than the diffraction limit of light,” says Thywissen. “What is new in our research is that the spacing between the features can also be much smaller, even when using light to do all the patterning.” He says that demonstrating this potential will require more laser power and a more finely collimated atomic beam.

Water powers novel chips

Biologists have already started to use microfluidic systems to scale down a number of laboratory techniques, but to date these systems have been stand-alone devices. On the other hand, integrated workstations for biologists take up entire laboratories and are expensive and time-consuming to operate. In contrast, Thorsen and colleagues used established lithographic techniques to produce two microfluidic devices from single slabs of polydimethylsiloxane that have an area of just a few square centimetres and can be used to carry out a range of operations.

The researchers used their first chip as a memory device. It consists of 1000 cells, arranged in a grid of 25 rows and 40 columns. Each cell serves as a binary bit and is initially full of a sample liquid. To add data to the device a micromechanical valve is opened in every cell within the first column, allowing the contents of each cell – if it is to be set to zero – to be flushed out by a stream of water passing along the respective row. This process is repeated for each column in the grid.

Thorsen and co-workers’ real innovation was being able to restrict the number of electrical inputs needed to control the device. Rather than control the flow of water in each row and column using a separate valve, the researchers arranged groups of valves across multiple channels. In principle, this technology can be easily scaled up since an increase in the number of electrical inputs permits an exponential increase in the number of water channels.

To demonstrate the principles of the chip, the researchers loaded dye into each cell and flushed out the dye from those cells needed to produce the letters “CIT”. In this way, the chip can function as a display, and has the advantage that it requires very little power to retain an image.

The researchers designed the second chip so that it can perform more complex operations, allowing them to study many copies of the same chemical reaction. Two different sample liquids are loaded into each cell and initially separated using a barrier valve. These valves can be turned on and off individually and the contents of each cell inspected one at a time.

Poles hint at past climate on Mars

Taken over 30 years ago, the first pictures of the martian polar caps showed that they consisted of layers of material, each of which is thought to have been deposited during different climatic periods. Astronomers believe that these horizontal layers consist of frozen water and dust, with a seasonal coating of frozen carbon dioxide. But the poor resolution of these images made it impossible to study the caps in detail.

Now the Mars Orbiter camera has taken pictures that reveal details on the polar caps as small as tens of centimetres. Laskar and colleagues focused on an escarpment in the northern polar cap in which many layers were visible. The team calculated the thickness of these successive layers by measuring their reflectivity, and then modelled the motion of Mars over the last ten million years.

Over such long periods, both the orbital eccentricity and the rotational obliquity of Mars – the angle its axis makes with the plane of its orbit – fluctuate greatly. These irregularities combine to make the long-term motion of Mars highly complex. Since this motion determines how much sunlight reaches the martian poles, it also has a strong influence on the climate in those regions.

When Laskar and colleagues compared their measurements with the past motion of Mars, they discovered that the thickness of the layers in the escarpment was strongly linked to the amount of sunlight that had reached the north pole over a given period.

Laskar and colleagues also estimated that the material in the northern polar cap was deposited at a rate of about 0.05 cm per year, which would suggest that it is just five million years old. This period coincides with a spell of high rotational obliquity – and therefore sunny conditions at the north pole that might aid deposition – but Laskar and colleagues stress that this is an open question.

Now that Laskar and co-workers have discovered the link between the structure of the polar caps and climate, they hope that further studies will reveal the processes underpinning it. This could help astronomers to understand how water was distributed on Mars in the past, and how apparently young features elsewhere on Mars formed.

Bell Labs physicist fired for misconduct

Schön was first suspected of scientific misconduct earlier this year when physicists noticed similarities between the graphs in two papers published in Science and one published in Nature. When further suspicious similarities between other papers came to light, the owners of Bell Labs, Lucent Technologies, set up a high-profile committee to investigate if the data had been fabricated. The committee, which was chaired by Malcolm Beasley of Stanford University, questioned Schön as well as his three principal co-authors – Zhenan Bao, Bertram Batlogg and Christian Kloc.

The committee has found that Schön – who made all of the devices and carried out all of the measurements and data-processing himself – showed “reckless disregard for the sanctity of data in science”. According to the committee, Schön substituted whole data sets to represent different materials or devices. He also substituted data curves — and even parts of curves – in multiple figures that supposedly represented different materials and devices. It found that he had failed to maintain proper lab records and had deleted all of the original, raw electronic data files, claiming that his old computer did not have enough memory. “Such practices are completely unacceptable and represent scientific misconduct,” says the committee.

Although Schön disagrees with the committee’s conclusions, he admits that he made mistakes, which he “deeply regrets”. However, he insists that all of his publications were based on experimental observations. “I am convinced that they are real,” he says in an appendix to the report. “I have observed experimentally the various physical efforts reported in these publications, such as the quantum Hall effect, superconductivity in various materials, lasing, or gate-modulation in self-assembled monolayers.”

Schön’s co-authors, however, have all been found not guilty by the committee of any charges of misconduct. But it declined to comment on whether they had acted in a professionally responsible manner, concluding that “in one case questions remain that the committee felt unqualified to resolve, given the absence of a broader consensus on the nature of the participants in collaborative research endeavours.”

Laser pioneer loses court battle

Nakamura filed his lawsuit on 23 August last year, claiming ownership of the patent and requesting ¥2bn (about £10m) in compensation. The patent dates back to 1991 and relates to a vapour deposition technique that Nakamura used to produce indium gallium nitride, the active layer in Nichia’s blue LEDs and lasers. After commercializing the technology, Nichia’s annual sales grew from just over ¥20bn to ¥80bn in 2001, around 60% of which was generated by nitride-based LED products.

These figures reflect the fact that blue lasers could increase the storage capacity of compact discs and DVDs by a factor of four or five, and that blue LEDs, in combination with red and green LEDs, may replace conventional light bulbs.

When Nakamura filed each of the dozens of patents that he authored while at Nichia he received ¥10,000 (about £50) and the same amount when they were granted. During the development of the vapour deposition technology, Nakamura ignored written instructions from his superiors to stop working on blue LEDs.

Under Japan’s patent law, an employee owns a patent filed while working for a company, although the company also has rights to use the invention. However, the court accepted Nichia’s claim that it owned the patent because Nakamura “received ¥20,000 in reward and filed no objection for over 10 years after the patent application”.

The patent law also requires companies to reward their employees for patents that are transferred to the employer. The court in Nakamura’s case ruled that he is eligible for a “proper amount of rewards” and is now considering that aspect of the lawsuit.

Nakamura’s attorney said the decision upholding Nichia’s ownership of the patent was “totally unexpected” and that an appeal would be filed.

Cosmic microwaves get polarized

Cosmologists believe that the photons created in the big bang were scattered by free electrons in the early universe. But after 300 000 years, the universe had cooled enough for atoms to form, and there were no longer any free electrons to scatter the photons. This means that the properties of the photons – which have been stretched to microwave wavelengths by the expansion of the universe – reflect the properties of the universe at the so-called time of last scattering.

Recent studies of the spatial variation – or anisotropy – in the temperature of the cosmic microwave background have shown how matter was distributed when the universe was 300 000 years old, and have confirmed that space is flat.

But now cosmic microwaves are set to reveal more. When the photons from the big bang were scattered by free electrons, they would have become polarized in a way that would provide details about the dynamics of the early universe. Astrophysicists were convinced that this polarization would still be present in the cosmic microwave background – and now DASI has spotted it after monitoring the microwave signal from the sky above the South Pole for 200 days.

The measurements also agree with the predictions of the standard model of cosmology, in which the big bang was followed by an extremely short period of very rapid expansion known as ‘inflation’. One mysterious feature of this model is that ordinary matter accounts for less than 5% of the total mass and energy of the universe. The vast majority comes in the form of ‘dark energy’, which is needed to explain why the expansion of the universe continues to accelerate against the influence of gravity. “Polarization is predicted. It has been detected and It is in line with theoretical predictions,” says Carlstrom. “We’re stuck with this preposterous universe.”

“Polarization is going to triple the amount of information that we get from the cosmic microwave background,” says John Kovac, another member of the DASI team. “It’s like going from the picture on a black-and-white TV to color.”

Future studies to measure the polarization even more accurately are already planned. “Detection of the polarization opens a new door to exploring the earliest moments and answering the deep questions before us,” says Michael Turner, also of the University of Chicago.

Cold antiatoms arrive in large numbers

The Standard Model of particle physics assumes that nature conserves CPT symmetry. In other words, it assumes that the laws of physics do not change if all the particles in an interaction are replaced by their antiparticles (C), all three directions in space are reversed (P), and time is reversed (T). It is well know that nature violates CP (charge-parity) symmetry but there is no experimental evidence that CPT symmetry is not conserved in nature.

Any violation of CPT symmetry would show up as a slight difference in the frequency of the electronic transition from the ground state to the first excited state in hydrogen and antihydrogen. This frequency has been measured with an accuracy of 1.8 parts in 10¹⁴ in laser spectroscopy experiments on cold hydrogen atoms. Creating and trapping cold antihydrogen atoms are clearly the first steps in any comparison.

Small numbers of antihydrogen atoms have been made at CERN and Fermilab before, but these antiatoms were moving too fast to be useful for precision experiments. Now the ATHENA collaboration – which includes physicists from Brazil, Denmark, Italy, Japan, Switzerland and the UK – has managed to produce large numbers of antihydrogen atoms for the first time.

All the traps in the ATHENA experiment are variations on the well established Penning trap, which uses an axial magnetic field and various electric fields to trap charged particles. Antiprotons from the antiproton decelerator (AD) at CERN are slowed down in a thin foil, trapped and then further cooled through collisions with cold electrons. The AD delivers about 20 million antiprotons in short pulses at 100 second intervals, and about 3000 of these are available for making antihydrogen after the trapping and cooling stages. Meanwhile positrons from the radioactive decay of sodium-22 are accumulated in a separate Penning trap.

To produce antihydrogen about 70 millions positrons are trapped and cooled to about 15 kelvin. Next about 10000 antiprotons (i.e., three AD shots) are launched into the positron cloud by changing the electric field, and the antiprotons and the positrons are allowed to mix. Antiatoms can only form if the excess energy and momentum in the antiproton-positron collisions are carried off by a third particle (so-called three-body recombination) or a photon (radiative recombination).

Evidence for antihydrogen production is obtained when an antiatom manages to escape from the trap and annihilates in the electrodes. The antiproton typically creates neutral or charged pions, while the positron emits back-to-back photons with a characteristic energy. The apparatus is maintained at a temperature of 15 kelvin and the antihydrogen atoms are thought to have a similar temperature. No antiatoms were detected when the temperature of the positrons was increased to several thousand kelvin.

The ATHENA team estimate that about 50,000 antihydrogen atoms were produced during the experiment but they are not sure of the absolute production rate, the dominant recombination method or the quantum state in which the antiatoms are produced. This last point is particularly important because hydrogen atoms (or antiatoms) can only be trapped if they are in their ground state.

The next step, says ATHENA team-member Mike Charlton of University of Wales Swansea, is to understand the antiproton-positron reactions in detail. Adding a laser system for spectroscopy experiments is likely to take several years, he says, and trapping antihydrogen atoms will take longer.

NASA names the successor to Hubble

The telescope’s primary mirror will contain 36 semi-rigid hexagonal segments or “petals”. Once complete, the mirror will be 20 feet in diameter – the primary mirror of Hubble is 8 feet across. And the TRW design has to be perfect because, unlike Hubble, it will be too far from Earth for astronauts to service it.

Before and during launch, the mirror will be folded up. Once the JWST is placed in orbit, ground controllers will send a command telling the telescope to unfold its mirror petals. The telescope will carry a near-infrared camera, a multi-object spectrometer and a mid-infrared camera/spectrometer to study a wide variety of astrophysical phenomena, including star and galaxy formation, extrasolar planets, supernovae and supermassive black holes.

The telescope will operate at the second Lagrange point some 1.5 million kilometres from Earth, where the gravitational attraction of the Sun and Earth cancel each other out. It will be possible to keep the telescope and its instruments at low temperatures without complex refrigeration equipment because a single-sided Sun shield on one side of the observatory will be able to protect it from the light and heat of both the Earth and the Sun.

Naming the telescope after an administrator is an unusual move for NASA. Existing space telescopes have been named after famous astrophysicists like Edwin Hubble and Subrahmanyan Chandrasekhar. Webb led NASA between 1961 and 1968 and was responsible for more than 75 launches during his tenure. He died in 1992.

HP announces molecular electronics breakthrough

The researchers made the device by creating a master mould of eight 40-nm wide parallel lines, which pressed into a polymer layer on a silicon wafer to make eight parallel trenches. After filling these trenches with platinum to form wires, the scientists deposited a single layer of electronically switchable molecules onto the surface. Finally, they rotated the mould and made another eight wires that ran perpendicular to the first set on top of the molecular layer.

The resulting device contained 64 regions where the top and bottom wires crossed. A bit of memory sat at each of these points, with roughly 1000 molecules sandwiched between the upper and lower wires. To write a bit, the researchers applied a voltage pulse to set the molecules’ electrical resistance. Measuring the molecules’ resistance at a lower voltage, meanwhile, allowed them to read the bit.

“We believe that molecular electronics will push advances in future computer technology far beyond the limits of silicon,” said R Stanley Williams, director of Quantum Science Research at HP Labs. “Capacity and performance could be extended enormously by layering molecular-switch devices on conventional silicon without the need for complex and expensive changes to the base technology.”

The team used acombination of optical and electron-beam lithography and say that it took about a day to create the master, which included 625 separate memories connected to conventional wires so that they could communicate with them. “After that, it took just a few minutes to make an imprint,” said Williams.

The researchers also put logic in the same circuit by configuring molecular-switch junctions to make a demultiplexer – a logic circuit that uses a small number of wires to address memory. HP Labs says that demultiplexers are essential to make memories practical.

“This is the first demonstration that molecular logic and memory can work together on the same nanoscale circuits,” added Williams. The memories are also rewritable and non-volatile, that is, unlike today’s DRAM (dynamic random access memory) chips, they preserve information stored in them after the voltage is removed.

Williams made the announcement last week at a symposium celebrating the 175th anniversary of the KTH Royal Institute of Technology in Stockholm, Sweden. HP Labs has received four US patents in connection with the work.

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