Sunday, January 14, 2018

Should The Standard Kilogram Be Redefined?

Although the platinum-iridium alloy standard kilogram had served us very accurately since 1879, is there a need for a more accurate kilogram standard? 

By: Ringo Bones 

The egg-sized platinum-iridium alloy cylinder that has officially defined the mass of a kilogram may soon be set aside in favor of a measurement that not only is more accurate – but one that is actually defined by fundamental constants of nature in order to make it several magnitudes more accurate than anything that is used before. The platinum-iridium alloy defining the standard kilogram known as “Le Grand K”, has sat inside a hermetically sealed room in Paris since 1879 and has served as the benchmark against which all other kilograms are compared. 

Sadly, the metric system’s “Le Grand K” has its failings. For one, it must be housed inside three glass bell jars in a climate-controlled room, under multiple locks and keys. The slightest fleck of dust or smudge of sweat or residue could alter its weight or corrode its surface, changing its mass. The hunk of metal is only taken out once every 40 years to be compared against similar replicas from around the world. Stephan Schlamminger, a physicist at the National Institute of Standards and Technology (NIST) in Gaithersburg, Maryland says:”The problem with the kilogram in Paris is that it’s so precious that people don’t want to use it.” 

So for years, physicists have chased an elusive dream: replacing the standard physical kilogram with a standard inherent in properties of nature such as the speed of light, the wavelength of photons and the Planck Constant (also called h-bar), which links the energy a wave carries with its frequency of oscillation. Well, physicists had managed to replace the x-shaped platinum- iridium bar which has served as the standard meter since 1890 with the 1,650,763.73 wavelengths of radiation from the krypton-86 atom back in 1960.
Scientists could use the Planck Constant to compare the energy of a wave with Albert Einstein’s iconic E=mc² equation; in that way, they would determine mass solely through the physical constants. Unfortunately, no one has yet been able to measure the Planck Constant to a level of precision that could rival what has been achieved using the Le Grand K as the benchmark. 

But researchers are making strides, and at the current pace, believe they can redefine the standard kilogram as soon as 2018. In the new study published in the journal Review of Scientific Instruments, NIST physicist Stephan Schlamminger and his colleagues managed to measure the Planck Constant to a high level of precision using the NIST-4 watt balance, a sophisticated scale that measures a weight by the electromagnetic force that counterbalances it. The electromagnetic force can then be used to calculate the Planck Constant. With this method, the NIST team calculated the Planck Constant down to an uncertainty of 34 parts per billion. That result lines up well with what other teams have calculated. A separate experiment measuring the atoms in a silicon sphere has calculated the Planck Constant down to an uncertainty of 20 parts per billion, while the best watt measurement has achieved an uncertainty of just 19 parts per billion. All of this spells good news to increase the accuracy of the standard kilogram and could eventually be used to determine the exact number of platinum and iridium atoms that have rubbed off the Le Grand K since we started using it in 1879.

Sunday, April 23, 2017

March For Science: Science Versus Donald J. Trump?

Even though the Earth Day “March for Science” was primarily aimed at the Trump Administration’s suppression of scientific research results, has America’s political and religious persecution of science finally reached a tipping point? 

By: Ringo Bones 

If you asked me, I wish that this year’s March for Science that coincided with this year’s April 22 Earth Day festivities should have been started back in 1996 to mark the moment that America’s radical right-wing Evangelical Christians started interfering scientific results of the National Academy of Science – especially ones that concern women’s health, climate change and environmental pollution. Fat forward to the election of Donald J. Trump into the U.S. presidency thanks to his “rhetoric” proclaiming that climate change is a hoax invented by The People’s Republic of China to help make them sell wind turbines and photovoltaic solar panels, many observant Christians finally reached the point of “Holy Jesus Hitler Christ, enough is enough” to have decided on this year’s Earth Day to march into Washington as a show of unity that Donald J. Trump’s Alternative Facts is no solution to global warming and sea level rise brought about by climate change due to man-made greenhouse gas emissions from industrial activity. 

Similar marches also happened around the world largely inspired by the march on Washington D.C. At a demonstration in Washington D.C., Dr. Jonathan Foley, the executive director of the California Academy of Sciences, said that research was being irrationally questioned, adding that attacks from politicians – especially from the U.S. Republican Party – “amounted to oppression”. According to Dr. Foley, skeptical politicians in DC are specifically targeting science that protects our health – especially women’s health – our safety and the environment. “Science that protects the most vulnerable among us”, Foley said. In short, everyone the world over protested on this year’s Earth Day against what they consider to be an “alarming trend” among politicians for discrediting their research.


Sunday, January 10, 2016

Jahn-Teller Metals: A New Form Of Matter?

Given its ability to become an insulator and a superconductor just by varying the applied pressure, are Jahn-Teller metals qualify as a new form of matter? 

By: Ringo Bones 

Back in May 12, 2015, researchers at Japan’s Tohoku University are making a bold claim saying that they had discovered an entirely new form of matter. The team led by Kosmas Prassides, says they’ve created what’s called a Jahn-Teller metal by inserting atoms of rubidium – a strange alkali metal more chemically reactive than pure metallic sodium – into buckyballs or buckminsterfullerene, a pure carbon structure which has a spherical shape formed from a series of interlocking polygons of carbon atoms. Buckyballs, which are somewhat related to other carbon supermaterials like graphene and carbon nanotubes, are already known for their superconductive capabilities. Here, while combining buckyballs and rubidium, the researchers created a complex crystalline structure that seemed to conduct, insulate and magnetize while acting as a metal. It goes beyond what ordinary matter can do. 

Jahn-Teller metals have recently created a buzz in the scientific community because such esoteric form of matter could serve as a key to understanding one of the biggest mysteries in physics that has baffled them since the late 1980s – i.e. the phenomenon of high-temperature superconductivity. Named after the Jahn-Teller Effect which is used in chemistry to describe how at low pressures the geometric arrangement of molecules and ions in an electronic state can become distorted. This new state of matter allows scientists to transform an insulator – which can’t conduct electricity – into a conductor by simply applying pressure. Could Jahn-Teller metals be used in constructing a new generation of piezoelectric materials for use in high fidelity audio someday? 

Element 113 Discovered At Last?

Long thought to be too unstable to be synthesized in our current atom smashers, is the recent announcement by the IUPAC serves as a true confirmation of the “creation” of Element 113? 

By: Ringo Bones

In January 4, 2016, officials from the International Union of Pure and Applied Chemistry (IUPAC) have announced the confirmation of the discovery of not only the elusive and unstable Element 113 but also its close siblings – elements 115, 117 and 118, stating that there is now enough evidence to give them permanent places on the Periodic Table of the Elements. Given that Element 113 is notoriously located in the unstable part of the Periodic Table that it is very likely that its half-life would probably be no more than a few microseconds and this also means that they also need their respective new, official names. 

By their very nature, you won’t find these four newly discovered elements occurring naturally in reasonable abundance because they can only be produced synthetically in our corner of the universe because their isotopes that we manage to synthesize so far decay in a matter of seconds or less. Their existence has been theorized but has been difficult to confirm. Until now, elements 113, 115, 117 and 118 had temporary names and positions on the bottom “Seventh Row” of the Periodic Table of the Elements because – probably since the 1980s – scientists have struggled to create them more than once for “scientifically verifiable results”. 

Kosuke Morita and team of RIKEN in Japan had been credited for the discovery of Element 113 and its close siblings. He says: “For over seven years we continued to search for data conclusively identifying Element 113, but we just never saw another event. I was not prepared to give up however, as I believed that one day, if we persevered, luck would fall upon us again.” 

Morita’s team has been credited with the confirmed discovery of Element 113, which means they’ve won the naming rights too. Until now, the element had been known by the temporary name ununtrium and the temporary chemical symbol Uut. The three remaining elements – 115, 117 and 118 – known temporarily as ununpentium (Uup), ununseptium (Uus) and ununoctium (Uuo) respectively will also get new names. 

Previous attempts to synthesize and the discovery of Element 113 and Element 115 were reported back in February 2004 following experiments carried out between July 4 and August 10, 2003. In these experiments, the primary product was the four nuclei of Element 115 isotopes. All these four nuclei decayed through the emission of u- particles to isotopes of Element 113. But the claim has not been ratified by the IUPAC back then because of a lack of scientifically verifiable reproducibility of the results. 

Ever since the discovery of Element 114 back in 1999 as the event was announced through e-mail which was then published in the April 1999 issue of Scientific American magazine by scientists at the Joint Institute for Nuclear Research in Dubna near Moscow reported strong evidence that they have created the heaviest element yet, one with 114 protons and i84 neutrons, many a nuclear physicists suggest that Element 113 is critically located in an unstable region of the Periodic Table that attempts to synthesize it only resulted in the creation of more stable heavier elements of a higher atomic number. A team led by Yuri Oganesian and Vladimir Utyonkov smashed a rare isotope – calcium-48 – with a plutonium-244 target to synthesize Element 114. Element 114 lasted an astonishing 30 seconds, far longer that the 280 microseconds of the previously discovered Element 112. The relatively long life of Element 114 was taken as proof that “islands of stability” exists in the super heavy element range. 

Wednesday, November 25, 2015

2015 – 100th Anniversary of Einstein’s Theory of General Relativity

With UNESCO marking 2015 as the International Year of Light and Light-Based Technologies, will the centenary of Einstein’s presentation of General Relativity inspire advances of current physics? 

By: Ringo Bones 

Back in November 1915, Albert Einstein presented to the world his “Theory of General Relativity” as a way to resolve another contradiction of physics not covered by his “Theory of Special Relativity” ten years before. According to Isaac Newton, gravity travelled instantly through the universe. But according to Einstein’s Theory of Special Relativity, nothing can go faster than light (but there’s an intriguingly convincing work by Thomas Van Flandern of the US Naval Observatory back in the mid 1970s proving otherwise that you can also check out). To overcome these incompatible views, Einstein introduced another, even grander theory in which space and time are not empty but are instead like a fabric that can be curved and stretched. This new picture – in which gravity originates from the bending of sheets of space-time – revolutionized cosmology and gave us the most compelling theory of creation, the Big Bang. 

Einstein’s Special Relativity was incomplete because it made no mention of acceleration or gravity. Einstein then made the next key observation: Motion under gravity and motion in an accelerated frame are indistinguishable. Since a light beam will bend in a rocket that is accelerating, a light beam must also bend under gravity. 

To show this, Einstein introduced the concept of curved space. In this interpretation, planets move around the sun not because of a gravitational pull but because the sun has warped the space around it, and the curvature of space itself due to the sun pushes the planets. Gravity does not pull you into a chair; space pushes on you, creating the feeling of weight. Space-time has been replaced by a fabric that can stretch and bend. 

General relativity can describe the extreme warping of space caused by the gravity of a massive dead star – a black hole. When we apply General Relativity to the universe as a whole, one solution naturally describes an expanding cosmos that originated in a fiery “Big Bang”. 

One of the simplest demonstrations using everyday objects to explain Einstein’s General Relativity that even the youngest school-kids can grasp is the bowling ball, marble and bedsheet set-up. Put a bowling ball on a bedsheet and shoot a marble past it. The marble will move in a curved line. A Newtonian physicist would say that the bowling ball exerts a “force” that “pulls” on the marble, making it move in a curved line. A Relativist would say that the ball curves the bedsheet and that the bedsheet “pushes” against the marble. This “simple” demonstration of Einstein’s General Relativity on how gravity shapes the cosmic space-time also explains why the 1919 solar eclipse observation that shows the sun’s gravitational well curving the path of starlight and the advancing perihelion of the planet Mercury that Newtonian physics is at a loss to explain why.  

Einstein’s General Relativity also shows that gravitational fields affect the flow of time – making them slow down which was only demonstrated unequivocably just recently – back in the mid 1990s - when atomic clocks were accurate enough to show the difference. Without correcting the effects of General Relativity, the Global Positioning System or GPS signals from the satellites to your receiving unit would have errors of several parts per billion – which is enough to make them useless. 

Recently, one of the most grandiose experiments to test the limits of Einstein’s General Relativity was the hunt for gravitational waves. Physicists can’t yet put the entire universe on a lab bench, but experimental tests of Einstein’s theories can now be carried out with subatomic precision. Perhaps the most elusive phenomena predicted by General Relativity – but has yet to be observed – are gravitational waves. In theory, a cataclysmic event such as a spiraling merger of two black holes should produce wavelike ripples in space-time that could still be detectible by the time they reach planet Earth. Two Earth-based observatories, Advanced LIGO and Advanced VIRGO at the University of Pisa in Italy, will look for disturbances as small as a hundred-millionth the diameter of a hydrogen atom.