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Concepts of Number Line and Time May Not Be As Intuitive As Previously Thought

Mathematics, often romanticized as human intuition, may not be as natural to the human race after all. In a new study conducted by the a team of scientists, led by Rafael Nunez, director of Embodied Cognition Lab, it appears that abstract mathematical concepts like the number line, which involves the mapping of numbers onto space, need to be taught and aren’t ‘hard-wired’.

Really so intuitive? Think again!

Nunez et al studied an indigenous tribal group from Papua New Guinea called the Yupno. The group lives in a remote part of the upper Yupno Valley in Papua New Guinea. The place has no roads. The team used a small plane and then hiked, carrying heavy equipment like solar panels, since the valley has no electricity.

The study

The main study was conducted with three groups – one comprised 14 illiterate adults, another comprising 6 adults who had received very basic schooling from within the tribal community and another control group in California, comprising adults with formal schooling. All the three groups were given several objects and a long line. Then they were asked to arrange these objects on the number line.
The Yupno were given oranges. The first group (of unschooled adults) arranged the oranges, but stacked them up at the two endpoints and a put a few in the middle, totally ignoring the extension of the line in between, which is one of the most important properties of the number line. The second group did a little better, using the extension a bit more, but not quite as evenly as it should be. The control group in California treated the number line as it should be. All this suggests only one thing – that the concept of numbers, especially their mapping onto space, is a concept that has to be taught and is not ingrained in the human brain. The ability to build this intuition might be evolutionary, but not the intuition itself!

What about time?

The team also analysed the crucial concept of time. We tend to associate the flow of time with spatial position, associating ‘forward’ for future and ‘backward’ for past. Interestingly, the Aymara of the Andes, a previously studied group of Nunez et al., does the reverse. The Yupno uses ‘uphill’ and ‘downhill’, says Nunez. They even use the three-dimensional topography of the valley to describe time, obviously conflicting with just the forward and backward 2-D notions of time.

Cooperrider, a co-author in the study, says:

When confronted with radically different ways of construing experience, we can no longer take for granted our own. Ultimately, no way is more or less ‘natural’ than the Yupno way.

There you go – Mathematics, or even time, is not as universal as we thought. If some definition or notion of mathematics seems obvious, it may be because we lack imagination.

The study appears here:http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0035662

Presenting Deus: A Full Blown Simulation of the Entire Universe

Scientists have been able to recreate the entire Universe inside a computer for the first time ever. A simulation running on a supercomputer, tracking a mind boggling 550 billion particles as they evolve, has been able to recreate the structure of the Universe right from the Big Bang to the present day.

Simulating the Standard Model of Cosmology

This is the first in the series of three simulations to be carried out on GENCI’s new supercomputer, CURIE at CEA’s TGCC (Tres Grand Centre de Calcul) performed by researchers from Laboratoire Univers et Theorie (LUTH). This takes into account the standard model of cosmology with the cosmological constant built in. Successive runs will improve upon this result with more data, especially about the distribution of dark matter and dark energy. The project, called Deus: full Universe run, will seek answers to the cosmological questions in a way similar to what the LHC follows in order to get answers.

Comparing Deus' size to previous simulations! Bottomline: Deus is HUGE!

Why simulation?

The physics at the LHC is massively complicated by the presence of so many particles and so many end states of a certain collision. It is impossible to analytically solve for the end state, so scientists use models before they begin an experiment. These simulations reveal what the most likely result of a certain collision is given certain parameters and bounds on certain numbers. The actual run either confirms the simulation, or discards it. This is a far more efficient process than reconstructing the interaction by looking at the end states, which is the other alternative.

The Deus simulation does something like that. They let the 550 billion points evolve and see what the end state is. This has enabled them to count the number of galaxy clusters which are more massive than a hundred thousand billion solar masses (that’s VERY heavy, by the way) and the number comes out to be 144 million. The first galaxy cluster formed 2 billion years after the Big Bang, according to the simulation. It also shows the most massive galaxy cluster – with a mass of 15 quadrillion (or 15 thousand trillion) solar masses!

 

Relics of the Early Universe

The simulation also revealed fingerprints of the inflationary era in the form of fluctuations in the Cosmic Microwave Background Radiation. If the Big Bang and inflation is true, then there must be radiation left over, which is constantly weakening. This permeates all of the space in the Universe, thus the name Cosmic Microwave Background (CMB). It is believed that some quantum fluctuation, growing under the effect of gravity, gave rise to the galaxy and clusters we see today. The CMB was studied thoroughly by the WMAP studies. They also showed up in the simulation.

Where are we? That dot - that single dot - is the entire Milky Way!

The simulation also confirmed the presence of dark matter and gave a hint of how it might be distributed throughout the Universe. Present in this primordial virtual cosmic soup is the Baryon Acoustic Oscillations or BAO. This might be the answer to the long standing problem of baryon asymmetry – why matter outnumbers anti-matter in the Universe, whereas they should have been produced in equal numbers in the Early Universe.

Computing power – the sky is the limit

CURIE is one of the largest supercomputer facilities in the world. The whole simulation has taken a few years to put together. The whole project is expected to use more than 30 million hours (or 3500 years) of computing time on all CPU’s of CURIE. The amount of data processed comes out to be 150 PB (peta bytes). This amounts to all the data on 30 million DVD’s. State-of-the-art compression technology has allowed researchers to reduce this entire jungle to 1 PB.

Future

Two more simulations are to follow! They will test out rival cosmological models. The simulation is also expected to reveal structures we have not been familiar with before. This will provide scientists a search parameter for current projects like PLANCK and future ones like EUCLID.

More info at this CNRS press conference: http://www2.cnrs.fr/en/2013.htm

Google Celebrates Earth Day ’12 With Doodle

Earth Day! The day when there is a call for each one of us to do our little bits for the planet. Mobilize the Earth is the slogan, and this is the day to remind ourselves of the responsibilities again. Google honours Earth Day with a very beautiful doodle.

The Doodle

Google did this last year as well – coming up with an awesome doodle back then. This time, it’s not as great as the last year, but it’s very pleasing. The doodle shows flowers lined up in shapes that spell out ‘G-O-O-G-L-E’. The doodle is not a static picture, and you can see the flowers growing, representing the Earth full of beauty. The colour of the flowers on each of the letters is the same as the colours of the letters on the regular Google logo. Nice and subtle!

Renewing the Pledge to the Planet

We had told you the brief history of Earth Day last year. The pledge this year is multi-pronged. We need to find viable alternative energy sources, save species, plant more trees, reduce carbon footprint and, most importantly, provide enough resources to teachers all over the world so that the information can be brought to the millions of children who are to form the future of our planet. There is no guarantee, in fact quite the reverse, that they will be spared the massive environmental changes – the debts of the generations preceding them.

Resources

The official site of Earth Day is www.earthday.org/2012. You’ll find all the news you need about Earth Day and the activities. Remember this is just a formal token day – the work happens all around the year.

In order to fulfill the dream of ‘A Billion Acts of Green’, the Earth Day Network launched an initiative with acclaimed director James Cameron which involves planting a million trees. This has led to the swelling of the online community members to a staggering 900,000.

The coolest thing on the website is the Carbon Footprint calculator. The app takes in your location, asks a few simple questions and then spits out your carbon footprint. Cool!

Get to know how you can help! Everyone counts.

Scientists Create Artificial DNA, Observe Darwinian Evolution In Them

The very basis of life can now be created in the laboratory and it’s not unique. What more this artificial genetic material can mingle easily with the real thing, even evolving as the real thing does. The creation of artificial DNA and RNA strands have been reported by Pinheiro et al. They have even observed their evolution.

A new class of molecules, very similar, but not quite

Till now, the only molecules known to be capable of undergoing Darwinian evolution were RNA and DNA, but this discovery suggests that there might be a lot more candidates that fit the bill. There is really no “Goldilocks solution”.
DNA (or RNA) has a double helical structure, meaning that it looks like two strips of paper wound around each other in a helical fashion. The structure is ladder like – with each rung consisting of two nucleotide bases held together by sugar molecules.

The Structure of DNA. The A,C,G and T label the nucleotides.

Pinheiro’s group retained the nucleotides of DNA – the Adenine, Guanine, Cytosine and Thymine (or Uracil, in case of RNA) – but altered the sugars that bind these nucleotides together. In this way, he created XNA, with the ‘X’ standing for the sugar used. DNA, or deoxyribonucleic acid, uses deoxyribose as the sugar, while RNA, or ribonucleic acid, uses ribose as the sugar. But these use different sugars, thus giving them different names. For example, arabinose is the sugar in ANA, flourarabinose in FANA, threose in TNA, a “locked” ribose in LNA and a cyclohexane in CeNA.

Retention and copying of information

Here is the crucial bit: Even though the sugar bases were changed, the nucleobases being the same meant that these artificial XNA’s behaved exactly like the DNA found naturally. They could even pair up with the naturally found DNA.

Here is another crucial bit of the story: When DNA or RNA create copies of themselves, they use helper molecules called polymerases. These polymerases separate the two chains of the double helix structure, read the sequence of letters, helps in the formation of a similar chain, zips the whole thing back again and creates a new DNA molecule, all in this process called transcription. Evolution – or small genetic changes in the DNA structure – happens the copy of the DNA is not exactly like its parent. Environmental factors then ‘selects’ the more competitive versions of these modified DNA molecules and this helps them create more copies of themselves. Thus, a trait is acquired and another is lost.

Building your own genetic copy machines

The team had to build separate polymerase molecules to help transcribe the XNA’s. They were able to, thus, transcribe the code of the synthetic DNA to natural DNA and then back to the synthetic DNA. The XNA’s thus formed are just as immune or vulnerable to the original DNA. XNA’s must also be able to proliferate just like DNA does without any external help, in a process called amplification. Amplification was noticed with the artificial polymerases and the XNA’s. This is important, otherwise the XNA’s won’t be able to undergo Darwinian evolution like DNA.

In one of the experiments, a control was set up. The factors were controlled such that if the XNA did not ‘cling on’ to a particular protein, it would be washed away. Pretty soon more and more XNAs began developing this trait. This again proves that the two very important traits of inheritance through genetics and selection – information storage with high fidelity of copying and propagation of mutations – are not characteristics of just DNA or RNA. This gives the grand possibility of finding a whole new structure of biochemistry.

Maybe novel forms of life are not that far away in the future!

Study and the technical paper here: http://www.sciencemag.org/content/336/6079/341.abstract

Scientists Split The Electron, Create an ‘Orbiton’ For The First Time Ever

Condensed matter physicists are known for creating miracles and they haven’t disappointed! They have just split the electron into two, creating a hitherto unobserved ‘orbiton’ in the process. While this has immediate consequences in theoretical condensed matter physics, like figuring out how high temperature superconductivity occurs (more later), the very idea of this is just too cool.

An explanation for superconductivity?

The ‘pieces’ of the electron

Condensed matter physicists have long identified that in a chain of atoms (called a ‘spin chain’), aligned in a particular direction, especially in the presence of a magnetic field, electrons can be thought of as particles being made up of three components. One component represents the charge(a ‘holon’), another the spin (a ‘spinon’) and a third one should store the orbital location information (an ‘orbiton’). Do note, however, that these three components exist independently only inside the material, not outside it. Outside the material, the electron is just the elementary particle – unbreakable into other particles – just like we know it to be.

History revisited

Fifteen years ago, a team of scientists, led by C. Kim of Stanford University, split the electron into its holon and spinon components. The material they used was ‘one-dimensional’ Strontium Cuprate. Now, another team, led by J. van den Brink, have split the electron into a spinon and an orbiton, making it the first ever spectroscopic observation of a free orbiton. The material is another version of Strontium Cuprate.

Performing a miracle with a laser

The team fired a beam of X-ray photons into the one-dimensional material. The electrons in the outer orbitals were excited to a higher orbital. In this process, the electron can separate out into a spinon and an orbiton. And this is exactly what the scientists got.

When the electron got excited to a higher orbital, the laser light lost some energy. The scattered beam’s energy and momentum were plotted and compared with various computer simulations. The plot matched perfectly if one assumes that the electron has ‘split’ into an orbiton and a spinon. These two quasi-particles would be moving in opposite directions through the medium.

Van der Brink is more ambitious:

The next step will be to produce the holon, spinon and the orbiton at the same time

Problem in superconductivity

So what theoretical problem in superconductivity does it really solve?

The long standing problem in superconductivity (the phenomenon of flow of electric current through a material with zero resistance) has been the problem of high temperature superconductivity. No one know how some materials manage to superconduct at temperatures such as -196 degrees Celsius, which is much higher than the previously known -268 to -263 degree Celsius. No one knows what conducts the current through the material. There is a theory that orbitons might be the key.

To have the power to create your own materials and rediscover one of the oldest discoveries of ‘modern’ science is to be able to do modern day alchemy. It’s a miracle, indeed.

The paper appears here: http://www.nature.com/nature/journal/vaop/ncurrent/full/nature10974.html

Was Life On Mars Discovered 30 Years Ago?

Simply put, there is life on Mars – or at least that’s the most plausible explanation that NASA scientists can put forward in order to explain certain observations in the lab. A robotic mission launched thirty years ago, the Viking 1 and Viking 2, brought soil samples back to Earth and these have been thoroughly tested for the presence of Martian life, and the tests have been encouraging.

Life Hiding Somewhere?: Photo returned by the Viking Spacecraft (Photo Courtesy: GSFC, NASA)

One of the packages brought back by the Viking spacecraft was collected by the Labeled Release (LR) apparatus. This sample is particularly interesting.

The ticks of life

Soil microbes metabolize and release carbon dioxide, using up minerals in the soil. The carbon in the carbon dioxide contains one radioactive atom in a million million atoms, but since there are lots of carbon atoms around, there is a lot of radioactive carbon as well. And this shows up in any instrument that measures radioactivity, like a Geiger Counter. So the idea is that if a soil sample emits more than its share of radioactive rays, the chances are very high indeed that there are microbes inside, that are churning out carbon dioxide gas, which can escape and be detected. The detector will produce more counts than normal.

They found exactly that! A control sample was put in to confirm that this is indeed due to some source of microbe inside the soil sample. This sample was baked at a high temperature to kill any microbe that might be present. When the two samples were checked for radiation, the unbaked LR sample clocked around 10,000 counts per minute, while the background was only about 100.

However, this is not true of the other two experiments on the Viking spacecraft. This non-confirmation led to the dismissal of the probability of life.

The diurnal cycle of life

Life on any planet, especially if local, adjusts its living patterns – sleeping, hunting etc. – according to the clock on that planet. Lifeforms on Earth have a 24 hour clock schedule, but on Mars the day is 24.7 hours long, and that will be the so-called ‘circadian rhythm’.

The funny thing is that the radiation emitted by the LR apparatus sample also shows this daily cycle. The radiation goes down, indicating a period of inactivity, then goes up again. The oscillation is periodic with the exact period of 24.66 hours.

Joseph Miller, a neurobiologist at University of Southern California, and a member of the study says:

That is basically a circadian rhythm, and we think circadian rhythms are a good signal for life.

No one has yet cultured a Martian microbe. The next spacecraft explorer – Curiosity – which is scheduled to land on Mars in a few days will shed much more light on this very critical issue.

We may not only have company in the Universe, it might even be just next door.
Want more info? Visit this: http://www.ijass.org

Eureka? Stem Cells Breakthrough Allows a Possible AIDS Cure

Stem Cells are the way forward for medicine and this is another confirmation of that. Just ahead of the upcoming World AIDS day, comes a wonderful piece of news – stem cells can be used to cure AIDS. This has been demonstrated the case of mice.

The T-cells

There are specific cells in the body’s defense system which can recognize HIV cells and kill HIV-infected cells, called cytotoxic T-lymphocytes. However, because HIV prevents the immune system from proliferating the WBC’s (white blood corpuscles- the soldier cells) during an infection, the T-cells aren’t produced in sufficient quantities. Now, scientists are using blood stem cells and ‘programming’ them to form mature T-corpuscles in sufficient number to attack the infection properly.

The tests were done in a lab in California University and the experiment subject was a humanized mouse. By humanized, it simply means that the progress of the HIV infection in the mouse mimics the progress in humans.

The experiment

The experimental subjects were observed for progress. Blood tests were done on the second week and sixth week. The scientists found that the T-cell count had increased and the HIV level decreased! Is this the long sought after cure?

Dr. Scott G Kitchen, lead scientist in this study, said:

We believe that this is the first step in developing a more aggressive approach in correcting the defects in the human T cell response that allow HIV to persist in infected people.

There are a lot more drug trials that need to be conducted before this can be thought of as a cure. Further, these have to be tested on human patients and their efficacy measured. The first step is a very promising one. It’s too early to say, but this can be the cure against AIDS.

The study appears here: http://www.plospathogens.org/article/info%3Adoi%2F10.1371%2Fjournal.ppat.1002649

Evidences of Majorana Particles Seen In Nanowires

A particle can be its own anti-particle – this was the phenomenal insight of the mysterious physics genius Ettiore Majorana, who went missing in 1938 and was never found. These particles have been widely searched for and has generated considerable amount of interest in the theoretical physics community, but have not been found. Now, the LHC has been quite actively searching for signatures of these particles.

A computer image of the nanowire created

Condensed Matter physicists join in…

Interestingly, and very importantly, a lot of modern day condensed matter research focusses on the type of signatures that Majorana particles can produce and how they can be detected. It is in this context that wonderful news comes in from a team of Dutch researchers, who have reported seeing signatures for these particles.

Device and Methodology

The team has been fabricated a device which comprises a nanowire forming a junction between a semiconductor and a superconductor. The team then applied a magnetic field parallel to the nanowire and this restricts electrons to only certain energies, creating so-called ‘band gaps’. Electrons can reside only in these band gaps.

The team then measured the conductivity of the material given different gate voltages and found that there are two small peaks in the conductances placed symmetrically about the zero bias voltage. Scientists think that these peaks are due to particles and anti-particles respectively, but they are just the same, i.e. they are Majorana fermions.

The team varied the magnetic field and the bias voltage over large ranges of values, but they dips stayed constant. All of this leads the team to conclude that the charge carriers in nanowire were indeed Majorana fermions.

The work appears here: http://www.sciencemag.org/content/early/2012/04/11/science.1222360.full.pdf

Don’t Know Whether a Word Is Real or Not? Ask a Monkey!

Reading – the primates are doing it right! A group of baboons was studied by the team of scientists led by Jonathan Grainger of CNRS and Aix-Marseille University, Marseille, France and they found that they can indeed read – and do so quite well.

The Underlying Science

When we read words, we use information we have acquired about those words over years. The information is primarily about the content of letters in the word, but involves many other forms as well, including an association of certain events, colours, personalities, emotions etc. The information relating the letters and how they are arranged in the word, called orthographic information, is the primary step taken by anyone learning how to read. This is the primary source of information that one uses to distinguish between real words and nonsense combination of letters. Humans have achieved a level of sophistication that even allows the concept of intricate spelling, identifying mistakes in spelling and etymology.

The study shows that orthographic information can be developed without any preexisting knowledge. That’s enough of abstract technical talk. In the experimental context, that simply means that the monkeys were really good at discriminating between actual words and nonsense ones.

How the Study Was Conducted

The monkeys were made to feel completely at ease, them being allowed to eat food and participate in the experiment at their own convenience. They could stop and start whenever they wanted. In the testing booths, they were presented with a four letter combination, either a sensible one like ‘WASP’ or something nonsense like ‘FSEV’. They could then tap at a plus sign on a touchscreen if they thought that the word was real, or an oval one if they reckoned that the word was just another combination of letters.

Of course, the monkeys were trained over a period of one and half months before this experiment, which, if you wanted to point out, would be much lesser than what a human child would take to learn words. Especially given the number of words involved. One baboon (VIO) got 81 words and another (DAN) got 308 words out of a total of 7832 non-words with nearly 75% accuracy! I am impressed.

The paper reporting the study appeared in Nature: http://www.sciencemag.org/content/336/6078/245.abstract

This just shows that reading and orthographic skills are not so rare in the primate family. All primates might be taught to read, to different degrees of success. The day is not far away when you’ll be able to chat online with a monkey… or you might have already done that.

Why No Tsunami After Giant Indonesia Quake, Ask Surprised Scientists

While the world has heaved a sigh of relief that the giant Indonesian quakedid not generate any tsunami, scientists are puzzled. Given the large magnitude of the quake, there should have been a tsunami, especially since the epicenter wasn’t very deep (just 33 km below the surface) and it lies directly beneath the sea. The question is really this then: Why was there such a huge tsunami during the 2004 quake, measuring 9.3 on the Richter Scale, while this one, just slightly weaker at 8.6 magnitude, didn’t generate anything even remotely similar?

The location of the quake that struck Indonesia. (Courtesy: BBC)

Two Important Factors

Preliminary investigations by geologists point to two factors which together contributed to the diminished effect. One is the strike-slip fault line and the other is that the earthquake occurred within a plate, rather than at a subduction zone. Let me explain this one sentence and the orgy of technical terms used.

Subduction Zone

Subduction zone refers to the zone at which two tectonic plates join. In this zone, plates may get submerged or raised. Subduction zones are regions where the major volcanoes of the world lie in, and thus is given the name “Ring of Fire”. Typically, these occur in the oceans. The entire of the Hawaiian region, for example, lies in the subduction zone. The really major earthquakes have all happened in this zone.

Subduction zone

The present earthquake didn’t happen at a subduction zone. The epicenter was about 150 km from the nearest subduction zone. No plate was submerged or raised. It was a really big intra-plate quake. What has surprised scientists is how big this quake actually was. More of this after a bit.

Strike Slip Fault

The earthquake occurred on a strike-slip fault, which means that the two adjacent plates slid past each other, releasing the built up tension, rather than submerge and rise. This is THE crucial difference between this quake and the 2004 one. The 2004 quake occurred on a normal fault. Land (the sea bed) was violently raised, while another part was submerged. The released tension was directed upwards, rather than sideways, causing the huge waves.

Strike-slip fault. Note how the landmasses slide past each other.
Normal Faulting. One can see the displaced striations and that makes it clear that the rock has been uplifted and submerged along the fault-line.

I want to ram home this crucial point: the difference was the presence of shear in the present earthquake. The fault line sheared (or pulled apart horizontally, along the ground), rather than jut upwards, like it had done during the devastating 2004 earthquake.

Formation of a tsunami.

Scientists are still learning new things though. They are surprised as to how a strike-slip earthquake can be so strong in magnitude. The record was held by the giant 1906 San Francisco earthquake, along the strike-slip San Andreas fault, which measured 7.8 on the Richter Scale.

A Tsunami did form!

Strictly speaking, a tsunami was generated. The Indonesian coast saw the increase of water level by about 1 m or 3.3 ft. However this is nothing compared to the about 30 m or 100 ft waves generated by the 2004 earthquake. The land however has shifted by nearly 70 ft in the northeast-southwest direction.

Residents left their homes in search of higher ground in Banda Aceh, once the tsunami alert was sounded. (Photo Courtesy: National Geographic)

All tsunami watches, issued for all countries across the Indian Ocean, had been lifted by yesterday night itself. Lucky definitely, but humanity needs all the luck it can get right now.

Gravitational Lensed “Cosmic Mirage” Is Definitive Proof of Accelerated Expansion of Universe

The Universe is accelerating, says a team of researchers led by Masamune Oguri, Kavli IPMU and Naohisa Inada at Nara National College of Technology, courtesy the data acquired by observing distant quasars. This is supplementary to the studies of distant supernovae, which also showed that the Universe’s expansion is accelerating, and for which the 2011 Nobel Prize in Physics was given. This study with quasars again shows that dark energy is definitely present, but we still don’t know what it might be.

Larger Data and more inferences

The data is derived from the Sloan Digital Sky Survey (SDSS), the huge collaborative experiment responsible for tracking about 100,000 quasars for nearly 10 years, with nearly 50 new quasars discovered in the last few years. Quasars are bright objects, believed to be formed, or at least fuelled, by the accretion of gas and dust by a supermassive black hole. The infalling material glows due to the enormous heat produced and can thus be detected from very far away. This makes them ideal for mapping the gravitational lensing occurring in the Universe.

Prof. Oguri, heading the study, says:

In 2011, the Nobel Prize in Physics was awarded to the discovery of the accelerated expansion of the universe using observations of distant supernovae. A caution is that this method using supernovae is built on several assumptions… Our new result using gravitational lensing not only provides additional strong evidence for the accelerated cosmic expansion, but also is useful for accurate measurements of the expansion speed, which is essential for investigating the nature of dark energy.

The Science of Gravitational Lensing

Gravitational lensing refers to the bending of light due to the presence of matter in the path of light, as explained by Einstein’s General Theory of Relativity. This process creates (at least) two identical images of one object, separated by a gap, thus the name ‘Cosmic Mirage’, referring to the similar process by which mirages on Earth are created.

The formation of a Cosmic Mirage. The figure explains why the accelerated expansion increases the chances of gravitational lensing and why the images separate out further. (Courtesy: SDSS)

The farther away the quasar, the greater its chances to be gravitationally lensed. Accelerated expansion of the Universe increases the distance of the quasar from us and thus the images also seem to separate (refer to figure above). This can be used to deduce how fast the quasars are receding from us. By plotting the velocity graph (velocity versus distance curve), we can see the deviation from the straight line expected from Hubble’s law, if the Universe was expanding at a constant rate. Sure enough, there is deviation and all the deviations fall on a curve, showing that it’s not just a mere statistical fluctuation or measurement error. The Universe is indeed accelerating! And this suggests that the estimates for dark energy are also not very off.

Note the two distinct images formed by gravitational lensing in the zoomed in inset. This was captured by the Hubble Space Telescope and the quasar - SDSSJ1226-0006 - has been tracked by the SDSS. (Courtesy: SDSS and Hubble Space Telescope)

Dark Energy in Einstein’s Theory

Einstein’s theory of General Relativity allows for an expanding Universe without any extraneous assumptions. However, this expansion should have been at uniform speed. But it seems that the expansion rate is increasing. To get this prediction from Einstein’s equations, scientists tweak it a bit, adding a ‘cosmological constant’ term. This adds a bit of energy per unit volume of the Universe, contributing a lot to the entire energy of the Universe. By adjusting the sign of this extra term, the universe can be made to be accelerating.

In fact, it can be shown that we are exiting a phase dominated by matter, where the major contribution to energy comes from matter, and entering a phase dominated by the cosmological constant. This inevitably leads to accelerated expansion. We might not be able to see any galaxies in another 5-10 billion years, if the accelerated expansion of the Universe continues unabated.

The SDSS data also shows that treating dark energy as the cosmological constant is not such a wrong thing to do.

The future of the SDSS project is Planck and the SuMIRe projects. Both aim to study the distribution of cosmic dark energy and all this in the not-too-distant exciting future!

Source and more info at the IPMU original site: http://www.ipmu.jp/node/1281

Massive Earthquake Strikes Off Indonesian Coast; Tsunami Watch Issued [UPDATED]

A massive 8.9 magnitude Earthquake has just struck off the coast of North Sumatra, Indonesia about 400 km away from Banda Aceh. Banda Aceh is the same region which was devastated by the 26th December, 2004 Asian tsunami. A red alert has been sounded and a tsunami warning has also been issued.

UPDATE at 1720 on 11th April: There has been no reports of any tsunami that has been formed. The chances of a tsunami being generated are diminishing with time.

UPDATE: The strength of the earthquake has just been revised from 8.9 to 8.7.

Location on World Map

View Larger Map

Though weaker than that horrific earthquake, which measured 9.6 on the Richter scale, this present one is also a very strong earthquake in its own right. The earthquake struck at 08:38 UTC with its epicenter being 33 km below the surface. The epicenter lies 431 km from Banda Aceh.

The depth of the Earthquake at various points. (Courtesy: US Geological Survey)

Countries under tsunami watch

The Tsunami watch has been issued for the coasts of Indonesia, India, Sri Lanka, Australia, Myanmar, Thailand, Maldives, United Kingdom, Malaysia, Mauritius, Reunion, Seychelles, Pakistan, Somalia, Oman, Madagascar, Iran, UAE, Yemen, Comores, Bangladesh, Tanzania, Mozambique, Kenya, Crozet Islands, Kerguelen Islands, South Africa and Singapore.

Follow this link for the tsunami watch info: http://ptwc.weather.gov/?region=3&id=indian.TSUIOX.2012.04.11.0845

    Predicted Arrival Time for Tsunami for Indian Coastline, if a Tsunami is generated:

GREAT NICOBAR 1507 IST 11 APR
LITTLE ANDAMAN 1546 IST 11 APR
PORT BLAIR 1602 IST 11 APR
NORTH ANDAMAN 1622 IST 11 APR
CHENNAI 1657 IST 11 APR
KAKINADA 1735 IST 11 APR
TRIVANDRUM 1938 IST 11 APR
MANGALORE 1906 IST 11 APR
BOMBAY 2138 IST 11 APR

We will keep you updated with the latest as we get them.

How to Live Longer – From a 103-Year Old Nobel Laureate Who Still Works

She won a Nobel Prize in Physiology/Medicine in 1986 for discovering “nerve growth factor” or NGF, which is an important protein for survival of neurons. She still attends work everyday! So what’s odd there? Rita Levi Montalcini, the woman in question, is to be 103 years old on April 22nd. And the best is this: she might actually know how to live longer.

Dr. Rita Levi-Montalcini, the wonder woman

Her Story

Dr. Levi Montalcini’s is an amazing story. She obviously has great genes and might also be helping their cause in keeping her alive much longer than the normal human lifespan. It is probably ironic, and definitely sad, that she was discriminated against during the 2nd World War for being a Jew. Benito Mussolini, following the extreme Nazi example, introduced the “Law of Races”. She moved from Italy to Belgium in 1940 and then to America, where she worked on proteins. This is when she stumbled upon NGF.

The Secret

What’s her secret? It is possible that even she doesn’t know exactly, but she does use eyedrops containing NGF. It is very possible that NGF retards brain and nerve degeneration, keeping the senses keener for longer and the person alive.

She now works as a “Senator for Life”, a title which she apparently takes a bit too seriously. Yes, she attends work every single day and also gives speeches. She is now a moderate Left-Center supporter, beginning her political career at the age of 90.

Benjamin Button has serious competition from this Nobel Laureate who seems to get greener every passing day!

Miami Blue Butterfly Receives Federal Endangered Species Status

The U.S. Fish and Wildlife Service have designated the Miami Blue Butterfly as an endangered species. The sad news was announced via a press release on April 5, 2012.

Miami Blue Butterfly

This small butterfly used to inhabit an area stretching from the Florida Keys up to Daytona. It isn’t a migratory butterfly like the Monarch, so it has pretty much been confined to these areas. Many human factors such as agriculture and development threaten the butterfly. Environmental factors such as climate change have threatened it as well.  It appears now that the population has shrunk so much that they are only found on a few remote islands in the Keys.

The U.S Fish & Wildlife Service press release states:

Under the ESA, it is illegal to kill, harm or otherwise “take” a listed species, or to possess, import, export, or engage in interstate or international commerce of a listed species without authorization in the form of a permit from the Service.

Hopefully through conservation efforts, more can be done to save these little butterflies and their habitat. Just as humans can be a threat, we can also be good stewards and do more to conscious of impact our choices make on the environment as a whole. If you would like to learn more about conservation efforts visit the U.S. Fish & Wildlife website at http://www.fws.gov.

Data From LHC and Tevatron Shows No Signs of the Existence Of Extra Dimensions

Negative results are important and the LHC just shows that. While the LHC hasn’t been able to find the Higgs Boson with absolute certainty as yet, it has done physics great service by eliminating a lot of different possibilities and put stringent bounds on existing theories. The CMS collaboration at LHC has just released a paper reporting their findings related to the existence of hidden extra dimensions. This is crucial to the very fabric of string theory.

The CMS detector at LHC

The CMS hasn’t found anything in their data that indicates that extra dimensions exist. The team has looked at the energy range of 2.3 to 3.8 TeV, which is the typical collision energy of protons, when the LHC runs at 7 TeV beam energy. The LHC recently upgraded to 8 TeV, 1 TeV up from the usual, but there is little hope of finding things at that energy. We can only wait till the LHC resumes its run after the break it is scheduled to take in a few days. It will be back at 14 TeV and maybe then we can get something on extra dimensions.

And the Tevatron adds to the misery…

Not only the LHC, even the Tevatron data eliminates the presence of extra dimensions, at least at low energies. The Tevatron is dead, but the data is still there and the D-Zero detector team is looking at the energy range around 260 GeV and have found nothing.

So far, the theoretical bounds on the energies at which particles might couple to extra dimensions have large errors. So this result really tells us what the lower limit for any experiment searching for extra dimensions should be.

The LHC is continuing to negate anything beyond the Standard Model. It has got good data to verify the one last piece of the Standard Model – the Higgs Boson – and the search is in its last few days. It seems that the emergence of physics beyond the Standard Model, except in the neutrino sector, isn’t happening at the moment.