Science in 2015
(appeared in Dec 2014)

(link to main website)

There is promise of good things in science during 2015, says S.Ananthanarayanan.

Research in science and sharing of work is greater now than ever before and every day uncovers new discoveries and insights. The progress made in the recent months in many areas suggests that we can expect important results during the course of the coming year. A few of these would be:

The Large Hadron Collider: The facility at CERN, near Geneva, accelerates charged particles to unprecedented energies through a 27 km vacuum tube lined with powerful electromagnets working in unison. The purpose is to collide subatomic particles at near-light speeds, and energies of electrons driven by many thousands of billions of Volts, and then to examine the products of interactions.

The most promising current theory of the nature of matter, which seeks to explain both the fine-scale interactions of sub-atomic particles as well as the gravitational forces between planets, predicts the fleeting existence of particles with very high mass. It would be only in the most energetic of reactions, as there might have been at the start of the ‘big bang’, that such particles could arise. The first spell of the LHC, from 2008 to 2013, raised energies to 4 thousand times a billion electron Volts and created a sensation by revealing a particle that resembled the Higgs Boson. But analyses of the results, including a number of new, high-mass particles created, has raised more questions that it has answered and the current theory, of so called supersymmetry, is itself in question.

The LHC was shut down in 2013, for ramping up the capability and is due to reopen in March 2015 with twice the power, rising to about 13 thousand times a billion electron Volts. The results, once the collider gets going, would uncover new phenomena, which would either confirm and refine current thinking, or invite a correction of course!

Climate change: For all the proof of climate change, due to GHG buildup in the atmosphere, the world’s governments and industry have not made concrete progress to contain emissions. In the last international protocol of 2008, USA, the largest emitter of GHG, stayed out because limits were not imposed on developing countries. While USA took measures, nevertheless, China embarked on massive industrialization, and surpassed USA in GHG emissions. The level of GHG in the atmosphere is hence poised to cross 400 parts per million, the highest seen since millions of years.

In the context, the recent agreement by USA and China to contain emission forms solid basis for the UN conference on Climate Change, scheduled at Paris in Dec 2015. The expectation of the conference is that all countries in the world could agree on a legally binding set of specific emission limits which may be their last chance to avert ecological disaster.

Ebola virus: The outbreak in Guinea, Sierra Leone, Liberia, Mali, and Nigeria, in West Africa, has created a serious scare of spreading world-wide. The disease, which leads to death in 25 to 90% of the cases, is highly infectious and calls for an advanced level of isolation and community involvement. The world has reacted with testing all entrants at international borders and quarantine of infected persons, but it may be impossible to control a virus which compromises the immune system even while it causes internal bleeding and other symptoms.

Resources for rapid detection and isolation, and also trained personnel have been rushed to the affected areas for the best possible control. Vaccines are to be tried out early in 2015, and results may be in by June. Several drugs are under development, as also the use of the antibody-rich blood of persons who have survived. Ebola will be the focus of science, hopefully successful, all of 2015.

Into the solar system: Two mission of exploration would reach their destinations in 2015.

The first is DAWN, the space probe launched by NASA in 2007 to study objects in the asteroid belt, between the orbits of Mars and Jupiter. DAWN surveyed the 525 km Vesta, the second most massive asteroid, in 2012 and would reach the 590 km dwarf planet, Ceres, in April 2015. Ceres is believed to consist of a rocky core covered by a 100 km thick mantle of ice, with 200 million cubic kilometers of water.

The second mission is NASA’s New Horizons, a spacecraft launched in 2006 and due to reach the dwarf planet Pluto, at the outer rim of the Solar System, in July 2015. Pluto had at first been classified as the ninth planet, but it lost this status when the scattered disc object, Eris, which is 27% more massive, was discovered. Pluto is now known as the largest object of the Kuiper belt, a region beyond the orbit of Neptune, and extending nearly as far beyond. New Horizons would fly past Pluto and take pictures of Pluto and its five moons. And then fly on to probe one or two other Kuiper belt objects, depending on positions. Since passing Jupiter in 2007, New Horizons has been kept ‘hibernating’ for ten months of the years, to conserve fuel.

Space-time waves: Einstein’s General Theory of Relativity describes the force of gravity as curvature in space-time. A consequence of the theory is that great acceleration of masses should cause waves that would be reflected as instantaneous changes in distances in space. But the extent of variation is of the order of fractions of dimensions of atomic particles and is hence yet to be directly detected. The Laser Interferometer Gravitational-Wave Observatory (LIGO), is an arrangement of two four kilometer long light paths, which may be able to detect such fleeting variations. A laser beam is split in two and passed down each arm of the L, 75 times, back and forth, and then recombined. Slight variations in the length of either path would show up as an interference effect of the light beams. To eliminate physical, for example, seismic, causes of change in length, the experiment is done simultaneously at places that are far apart and events are counted as valid only if they occur at both places.

While there have been indirect ways to confirm Einstein’s prediction, LIGO, which is looking for direct evidence, has not been able to record anything of significance from 2002 to 2010. But the arrangement is being upgraded to be more sensitive, as ‘Advanced LIGO’, and is to become operational in 2015.

The origins of humans: Excavations at Sima de Los Huesos , or the the Pit of Bones – a cave site in Atapuerca Mountains, northern Spain- have revealed a cache of 28 skeletons that were dated at 300,000 years to 600,000 years ago. The Spanish paleontologists teamed up with the Max Planck Institute and analysis of a part of the DNA, called the mitochondrial DNA, showed similarity with a stream of human species called the Denisovans, found in ranges from Siberia to South-east Asia. This fact, although the physical features are akin to the Neanderthal man, who were found more to the north, suggests that the skeletons were of a common ancestor.

But work is on to decode the complete, or the nuclear Genome from the ancient skeletal remains and results expected in 2015 could throw new light on the mobility and inbreeding of ancient, proto-human species.

Do respond to :