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Prof Claudia de Rham’s ‘massive gravity’ theory could explain why universe expansion is accelerating Cosmologists don’t enter their profession to tackle the easy questions, but there is one paradox that has reached staggering proportions. Since the big bang, the universe has been expanding, but the known laws of physics suggest that the inward tug of gravity should be slowing down this expansion. In reality, though, the universe is ballooning at an accelerating rate. Scientists have come up with a name – dark energy – for the mysterious agent that is allowing the cosmos to expand so rapidly and which is...

Switzerland has minted the smallest gold coin the world has ever seen, state-owned Swissmint announced Thursday. The 2.96-millimeter (0.12-inch) gold coin, weighing only 0.063 grams (¹⁄500th of an ounce), is so small the viewer needs to squint closely to see world-famous physicist Albert Einstein sticking his tongue out. The coin has a nominal value of ¼ of a Swiss franc (26¢, €0.23) and can be ordered online. According to Swissmint, 999 of the coins have been made, and a single coin will be sold for 199 francs and accompanied with a special magnifying glass so owners can see Einstein. …

Albert Einstein received the Nobel Prize for explaining the photoelectric effect: in its most intuitive form, a single atom is irradiated with light. According to Einstein, light consists of particles (photons) that transfer only quantized energy to the electron of the atom. If the photon’s energy is sufficient, it knocks the electrons out of the atom. But what happens to the photon’s momentum in this process? Physicists at Goethe University are now able to answer this question. To do so, they developed and constructed and new spectrometer with previously unattainable resolution. Doctoral student Alexander Hartung became a father twice during...

Between May 29 and July 1919, an expedition organized by Cambridge astronomer Arthur Eddington and the Astronomer Royal Frank Dyson photographed first an eclipse of the Sun (May 29) and then, a month later, the stars where the Sun had been during the eclipse. By comparing the two photographs, the deflection of light caused by the Sun’s gravity could be precisely measured. Einstein’ gravity theory predicted a deflection value of 1.75 arcseconds, and Newton’s gravity theory a value half that. The results were announced in November 1919 to a joint meeting of the Royal Society and the Royal Astronomical Society....

Some six months after the Great War of 1914-18 ended, Arthur Eddington travelled at the head of a team on a scientific expedition to the island of Principe off the coast of Equatorial Guinea in West Africa. He headed one of the two teams of astronomers assigned by a Joint Permanent Eclipse Committee of the Royal Society and the Royal Astronomical Society of Britain to observe and record photographically the full solar eclipse scheduled to take place on May 29, 1919. At the time under Portuguese rule, Principe was selected as one of the two sites – the other was...

Astronomers have been grappling with the mystery of dark matter for a long time, and I mean a looong time. The history of dark-matter investigations goes back at least to 1906, when physicist Henri Poincaré’s 1906 speculated about the amount of “matière obscure” in the Milky Way. Or really, it goes to back to 1846 and the first successful detection of dark matter: the discovery of the planet Neptune, whose existence had been inferred by its gravitational pull well before it was actually observed. Since then, scientists have identified many different dark components in space: collapsed stars, interstellar dust, hot...

A new Einstein cross is discovered March 18, 2019, Instituto de Astrofísica de Canarias The newly discovered Einstein Cross J2211-3050. An elliptical galaxy (the yellow object)  is acting as a lens, producing the four blue objects (marked ABCD) that are the images of a galaxy about 3 times more distant. With GTC it was possible to isolate and disperse the light of objects ABC, demonstrating that they belong to the same light source. Credit: Hubble Space Telescope Credit: Instituto de Astrofísica de Canarias This study, which has combined images from the Hubble Space Telescope with spectroscopic observations from the GTC,...

Albert Einstein was born in Germany on March 14, 1879. He began teaching himself calculus at age 14. With a doctorate from the University of Zurich, Einstein wrote papers on electromagnetic energy, relativity, and statistical mechanics. Einstein predicted a ray of light from a distant star would appear to bend as it passed near the sun. When an eclipse confirmed this, the London Times ran the headline, Nov. 7, 1919, “Revolution in science – New theory of the Universe – Newtonian ideas overthrown.” In 1921, Albert Einstein won the Nobel Prize in physics. Describing the theory of relativity, Albert Einstein...

Dozens of manuscripts belonging to Albert Einstein, many of them unseen in public before, have been unveiled by the Hebrew University of Jerusalem. More than 110 new documents are now on display at the university, marking the 140th anniversary of Einstein's birth. It was donated by the Crown-Goodman Family Foundation and purchased from a private collector in North Carolina. The manuscripts contain an appendix to Einstein's article on Unified Theory ... The collection includes scientific work by the Nobel Prize winner that has never been published or researched.

A letter written in German by Albert Einstein in 1954 is going under the gavel on Tuesday. Experts at Christie's auction house in New York estimate the so-called "God letter" could sell for up to $1.5 million (€1.3 million). "This remarkably candid, private letter was written a year before Einstein's death and remains the most fully articulated expression of his religious and philosophical views," said Christie's in a statement. The missive is referred to as the "God letter" because it addresses how Einstein felt about the characterization of God and Judaism in a then-recently published book on the subject by...

The problem with string theory, according to some physicists, is that it makes too many universes. It predicts not one but some 10500 versions of spacetime, each with their own laws of physics. But with so many universes on the table, how can the theory explain why ours has the features it does? Now some theorists suggest most—if not all—of those universes are actually forbidden, at least if we want them to have stable dark energy, the supposed force accelerating the expansion of the cosmos. To some, eliminating so many possible universes is not a drawback but a major step...

This artistÂ’s impression shows the path of the star S2 as it passes very close to the supermassive black hole at the centre of the Milky Way. As it gets close to the black hole the very strong gravitational field causes the colour of the star to shift slightly to the red, an effect of EinsteinÂ’s general thery of relativity. In this graphic the colour effect and size of the objects have been exaggerated for clarity. Credit: ESO/M. Kornmesser _________________________________________________________________________ Observations made with ESO's Very Large Telescope have for the first time revealed the effects predicted by Einstein's general relativity...

Credit: CC0 Public Domain _____________________________________________________________________________ Dan Hooper, a senior scientist with Fermi National Accelerator Laboratory has written a paper outlining a way future aliens could keep their civilizations alive in spite of the isolation due to an expanding universe. In his paper uploaded to the arXiv preprint server, he suggests they might consider collecting and storing stars. A Dyson sphere is a theoretical structure able to house a star. Originally proposed by Freeman Dyson, the sphere was originally envisioned as a group of satellites completely encompassing a star to capture all of its energy. That energy could then be...

The publication of Albert Einstein’s private diaries detailing his tour of Asia in the 1920s reveals the theoretical physicist and humanitarian icon’s racist attitudes to the people he met on his travels, particularly the Chinese. Written between October 1922 and March 1923, the diaries see the scientist musing on his travels, science, philosophy and art. In China, the man who famously once described racism as “a disease of white people” describes the “industrious, filthy, obtuse people” he observes. He notes how the “Chinese don’t sit on benches while eating but squat like Europeans do when they relieve themselves out in...

There are stars too faint to see in the night sky just a few light years away, yet a chance cosmic event gave us a glimpse of a star that would have otherwise been completely invisible due to its immense distance from Earth—a whopping 9 billion light-years away. A paper today in Nature Astronomy reports the discovery of the star, called MACS J1149 Lensed Star 1, or Icarus informally. Finding such a distant star is normally a tall order, but a larger object happened to pass in front of its home galaxy. When a large object passes in front of...

Gravitational waves have opened up new ways to test the properties of black holes — and Einstein’s theory of gravity along with them.We all dream the same dream, here in theoretical physics. We dream of the day when one of our equations will be plotted against data and fit spot on. It’s rare for this dream to come true. Even if it does, some don’t live to see it. Take, for example, Albert Einstein, who passed away in 1955, 60 years before his equations’ most stunning consequence was confirmed: Space-time has periodic ripples — gravitational waves — that can carry...

1. Starlight bends — but how much? Einstein performed a series of calculations to determine the size of the predicted shift but initially muffed the effort, arriving at a number that was half the correct value. Had the astronomers managed to test this number in their initial eclipse-viewing efforts, their observations wouldn’t have matched his prediction. But their attempts were stymied by weather in 1912 and by war in 1914. By the time they made the necessary observation, in the spring of 1919, Einstein had corrected his blunder — and astronomers saw exactly the shift that he had predicted. 2....

The note largely exceeded the estimated pre-auction price, which was placed between $5,000 and $8,000. The $1.56 million price included the buyer’s fee, the auction site stated. The Nobel-winning scientist wrote the note while he was in Tokyo, just after he was told he would be awarded a Nobel Prize in physics, Winner’s Auctions and Exhibitions said. A bellboy arrived at his room to deliver an item and Einstein didn't have cash to tip him. Instead, the scientist handed him a piece of paper with a message. "A calm and modest life brings more happiness than the pursuit of success...

For decades astronomers tried to prove Albert Einstein right by doing what Einstein thought was impossible: detecting the faint ripples in the universe called gravitational waves. They failed repeatedly until two years ago when they finally spotted one. Then another. And another. And another. Three American scientists — including one who initially flunked out of MIT — won the Nobel Prize in physics Tuesday that launched a whole new way to observe the cosmos. Sweden’s Royal Academy of Sciences cited the combination of highly advanced theory and ingenious equipment design in awarding Rainer Weiss of the Massachusetts Institute of Technology...

A group of high school and college teachers and students has transmitted sound pulses faster than light travels—at least according to one understanding of the speed of light. The results conform to Einstein's theory of relativity, so don't expect this research to lead to sound-propelled spaceships that fly faster than light. Still, the work could help spur research that boosts the speed of electrical and other signals higher than before. The standard metric for the speed of light is that of light traveling in vacuum. This constant, known as c, is roughly 186,000 miles per second, or roughly one million...