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Archive for the ‘Science’ Category

Only recently President Assad admitted his predicament. He is winning a war that he cannot hold because of severe shortage. The Syrian leader must have realized what mass exodus of his people in order to avoid conflict could do to a vast country like his. He also said the army faced a shortage of soldiers. Naturally. This just shows no country can survive if there are no people to make it work. Assad may sit like Robinson Crusoe considering himself as a monarch of all that he surveys. But without a subject he must be a monarch who must foul all over the palace and clear up the mess himself. What pomp! What circumstance! Having said this we shall see nature itself shows the truth is not in the glory of any one or his clan or tribe. These are all sustained by the most meanest article one would not have given a second thought.

Look at the snowflake, it shall not form without a speck of grit or dirt to work its magic on. Similarly our clouds.

Firstly consider planktons. They are like you and me just nobodies managing their role in the marine foodchain, at the bottom Nevertheless most life in the sea ultimately depends on photosynthetic plankton. Also known as microalgae, these tiny or microscopic organisms live near the surface and take their energy from the sun and pass it on through the marine food chain.

Clouds are made up of many tiny droplets of water that have condensed from water vapour onto microscopic particles floating in the Earth’s atmosphere. These particles are known as cloud condensation nuclei. Plankton essentially help provide clouds with these nuclei to form around.

The number of these particles in a given volume helps to determine the number of droplets in a cloud, which can have a big influence on how much sunlight a cloud reflects back into space. The more droplets a given mass of cloud water is broken up into, the more sunlight is reflected, as the overall surface area of the cloud’s droplets increases. Since a significant portion of the planet’s reflectivity, or albeido, is due to clouds, this can have a major impact on the energy balance of the Earth.

But these plankton have a big role to play above the surface of the sea too. In new study published in the journal Science Advances it is found that plankton help to control clouds over remote seas far from land. These clouds in turn bounce the sun’s energy back into space, regulating the Earth’s climate and keeping temperatures cooler than they would otherwise be without them.( (The Conversation-How plankton help control clouds over the world’s most remote oceans/July 21,2015-Daniel Grosvenor)

When we see how many societies are rewriting natural and divine laws we know such societies make capitalism continue as before. When they fatten certain sections on the grounds these are on the assumption that the hands that create national wealth have also ingenuity and daringness. How real are they? Their risk taking is simiar to a free booter who is licensed by the ruling class to slash and burn rain forests or drill remote places and siphon off precious natural resources. The governments would not want to know the truth and pretend it is all for the nation’s economy. In nature there is no such big or little but each part is connected to something else. In such a complex sysem nations that let some perpetuate tyranny over the rest in their license to exploit what is for all shoud be considered as evil.

The concept of nations based on geographical borders is an illusion so is determining value of any in terms of size. People count.

benny

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Quarks

What are we? Science was young when the ancient Greeks put forward a set of classical elements: from water, air, fire and earth; the Chinese believed in water, fire, earth, metal and wood. Still it was young and naiive. In this age of Large Hadron Collider in Geneva the Physicists would put down matter as made of twelve fundamental particles – quarks and leptons. These have no substructure and cannot be broken down into smaller particles. Quarks and leptons interact via four forces to make the universe we know today.

How these particles work to make matter.

The nucleus and the electrons are attracted to each other, exchanging photons. The force between the nucleus and electrons is the electromagnetic force.

Many atoms constitute objects in our everyday life as well as much bigger components of the universe such as stars and galaxies. The force dominating this level of macroscopic phenomena is gravity.

In an atomic nucleus a proton is made up of two up quarks and one down quark, and a neutron is composed of one up quark and two down quarks. The force that binds three quarks in a proton or a neutron is called the strong force and this force is due to exchanges of gluons. Having said this let us examine force mediator that facilitates exchanges. There are four such mediators the “gluon”, “photon”, “graviton” and “weak bosons”.

An atomic nucleus constitutes an atom together with electrons orbiting around it. The relation between the nucleus and electrons resembles the one between the sun and planets in the solar system.

In the centre of stars, huge energy is generated by nuclear fusion being mediated by weak bosons. This energy makes the universe bright. In nuclear fusion, a down quark is changed to an up quark by the weak force. Stars are luminous because the fundamental building blocks are changing their types and providing energy.

Quarks like to hang in groups

Although most physicists believe that quarks are the fundamental building blocks which make up the universe, no one has observed an isolated quark on its own. This is due to the nature of the strong force.

Like a nucleus and an electron that attract each other due to their electrical charges, quarks are combined together by their color charges.

Many atoms constitute objects in our everyday life as well as much bigger components of the universe such as stars and galaxies. The force dominating this level of macroscopic phenomena is gravity, intermediated by gravitons.

Experiments in 1968 provided the evidence for the quark model. The quark model actually explains the existence of more than 100 particles, all known as “hadrons” (as in Large Hadron Collider) and made up of different combinations of quarks. For example the proton is made of three quarks. If protons are hit hard enough, the strong force can be overcome and the proton smashed apart. With the LHC recently updated is powerful and the scientists are ready to look deeper into the world of quarks.

The Large Hadron Collider, famous for finding the Higgs boson, has now revealed another new and rather unusual particle. Pentaquarks are incredibly difficult to see; they are very rare and very unstable. This means that if it is possible to stick five quarks together, they won’t stay together for very long. The team on the LHCb experiment made their discovery by looking in detail at other exotic hadrons produced in the collisions and they way these break apart. All hadrons seem to be made up of combinations of either two or three quarks, whereas pentaquarks as the name suggests are made up of five quarks.

Why is this important?

The discovery answers a decades-old question in particle physics and highlights another part of the mission of the LHC. Discoveries of new fundamental particles such as the Higgs boson tell us something completely new about the universe. But discoveries like pentaquarks give us a more complete understanding of the rich possibilities that lie in the universe we already know.

By developing this understanding, we may get some hints about how the universe developed after the Big Bang and how we’ve ended up with protons and neutrons instead of pentaquarks making up everyday matter.(Ack: the Conversation,Feb15 of 2013,2015- Takashi Kobota/Gavin Hesketh)

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Classical physics implies that anything falling through the horizon of a black hole can never escape. But Hawking showed that black holes continually emit radiation once quantum effects are taken into account. Unfortunately, for typical astrophysical black holes, the temperature of this radiation is far lower than that of the cosmic microwave background and we have no way of proving it. If a black hole continually emits radiation, it will continually lose mass – eventually evaporating. Hawking realized that this implied a paradox: if a black hole can evaporate, the information about it will be lost forever. This means that even if we could measure the radiation from a black hole we could never figure out it was originally formed. This violates an important rule of quantum mechanics that states information cannot be lost or created.

Determinism implies that the state of the universe at any given time is uniquely determined from its state at any other time. This is how we can trace its evolution both astronomically and mathematically though quantum mechanics.

If a black hole can evaporate and information lost how will determinism work? Black hole physics provides a test for any potential quantum gravity theory. Whatever your theory is, it must explain what happens to the information recording a black hole’s history.

It took two decades for scientists and they have come up with an answer. They suggested that the information stored in a black hole is proportional to its surface area (in two dimensions) rather than its volume (in three dimensions). This could be explained by quantum gravity, where the three dimensions of space could be reconstructed from a two-dimensional world without gravity – much like a hologram. See a problem like quantum gravity can disappear if we make the universe is a hologram: the real action would play out where gravity is zero. In regimes where there are no analytic tests a holographic universe replaces actual proof.

In this context we have Maldacena conjecture and it  reconciles Einstein’s General Theory of Relativity and quantum mechanics.

Shortly afterwards, string theory, the most studied theory of quantum gravity was also shown to be holographic.

Using holography we can describe the evaporation of the black hole in the two-dimensional world without gravity, for which the usual rules of quantum mechanics apply. This process is deterministic, with small imperfections in the radiation encoding the history of the black hole. So holography tells us that information is not lost in black holes, but tracking down the flaw in Hawking’s original arguments has been surprisingly hard.

Which came first? chicken or egg? Maldacena conjecture in this case makes chicken the hologram projection of egg where gravity is zero. Conversely shall we say chicken is the hologram projection of an egg in another time zone?

In a 4-D world of chickens , the eggs are entangled only in a flattened 3-D scaled down version of reality. Both are present.( cf.universe as a hologram)

(Ack: The Conversation June 24, 2015 -Don’t fear falling into a black hole – you may live on as a hologram- Prof.Marika Taylor/ in theoretical physics at Uni. of Southampton)

benny

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Astrophysical journal of the 20th century was agog with Einsteins’ general theory of Relativity and this century is astir with Black holes. In our known universe the idea that no particle can pass faster than light was sacrosanct. Every theory had to fit in order to pass approval. In 2011 was a debate going on about faster-than-light neutrinos. Imagine the notion of the universe having internal boundaries! Only that we have not had any convincing proof to support this quirky idea. It has now been ditched.

What makes a black hole special is its event horizon. If you pass through you are lost forever, in the most complete way, from the universe you left behind. It’s a boundary to the knowable universe. Extraordinary claims require extraordinary evidence. The claim that the universe has internal boundaries is extraordinary. So what’s the evidence for event horizons? One may point to observations of hot matter around the postulated event horizon and say that matter is at least as far from the horizon as the size of the black hole itself. Einstein’s theory of gravity, describes these hot matter observations well, and if it continues to do so all the way down to the event horizon then black holes exist. But we’ve yet to see evidence for that.

Our theoretical explanations may require the existence of things for which there is no direct evidence. It happens all the time in physics. If you accept the Standard Model of Particle Physics then you probably believe in the Higgs boson even though it took a while in order to prove its existence. Similarly, if you believe general relativity then you probably believe in event horizons.

At best we may conclude the best theoretical model of the observational data implies a black hole. But that model includes general relativity, which we expect does not completely describe black holes, as it predicts a singularity – a point of infinite density and infinitesimal volume, at which space and time become infinitely distorted. Things can become quite weird is it not?

So when you come across the term “infinite” in physics it is more like the white spaces in old maps with a notation, ‘terra incognita’, meaning we have reached the limits of our understanding.

Thanks to Stephen Hawking who jiggered with black hole predicts small event horizons eventually explode due to’Hawking radiation.’

So it’s possible event horizons are where quantum mechanics first requires significant modifications to general relativity. Speculating further, it’s also possible that such modifications would prevent event horizons from forming. That might save us from living in a universe with parts that are unknowable.

‘Black holes are a bit like free will. Irrespective of the evidence, most of us live as if free will exists. And most astrophysicists live as if black holes exist’.

(The Conversation/ Black holes might exist, but let’s stay skeptical-Prof.craig savage, Theoretical Physics- Au.NU/ Nov.29, 2011)

(To be concluded)

benny

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When you drill into a rock the heat is transferred by the metal bit into the rock as well. The potential energy stored in a drill when electricity flows through it is simply transferred. In physics, energy is a property of objects which can be transferred to other objects or converted into different forms, but cannot be created or destroyed.

In a typical lightning strike, 500 megajoules of electric potential energy is converted into the same amount of energy in other forms, mostly light energy, sound energy and thermal energy.

As I mentioned at the outset all of the many forms of energy are convertible to other kinds of energy. The bottom line is that it obeys the conservation of energy. Common energy forms include the kinetic energy of a moving object, the radiant energy carried by light, the potential energy stored by an object’s position in a force field,(gravitational, electric or magnetic) elastic energy stored by stretching solid objects, chemical energy released when a fuel burns, and the thermal energy due to an object’s temperature.

What is heat? It is the energy stored in the vibrations of atoms,

In the 1930s, physicists started modeling atomic vibrations as particles. This is similar to the concept of light as both a wave and a particle we call a photon. Physicists called the sound wave particles “phonons,” derived from the Greek word for sound.

Today, physicists treat phonons as quasi-particles, having both wave and particle properties. Phonons carry both sound and heat. In the example of electric drill heat is carried primarily by the movement of electrons in the atoms.

Now heat and sound are related.

Sound is carried by periodic vibrations of atoms in gases, liquids and solids. When we talk to each other, the vocal chords of the speaker vibrate, causing the air coming from his lungs to vibrate as well. This creates sound waves, which then propagate through the air until they hit a listener’s eardrums and make them vibrate as well. From these vibrations, the listener can then reconstruct the speaker’s words.

Sound is affected by the surroundings in which it travels and by the frequency of the sound waves. We design musical instruments to manipulate the sound waves they produce. Further, we know that there are sound waves that are outside the range of human hearing, such as those produced by a dog whistle. As physicists have researched sound both inside and outside the range of human hearing, interesting properties have been discovered.

More than a hundred years ago, physicists understood that heat is simply the energy stored in the vibrations of atoms, and therefore realized that heat and sound are related.

(ack: Wikipedia/energy, the conversation-Joseph Heremans of 24 March,2015

benny

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According to Merriam-Webster dictionary a miracle is defined as an extraordinary event manifesting divine intervention in human affairs.

On closer examination many events touted as miracle can be interpreted as natural causes. In ancient Greece a bleeding Juniper tree caused great sensation and was venerated by people as a miracle.

‘The phenomenon of bleeding’ tree – in which a mysterious red liquid pours from chopped-down trunks – is one which has left scientists shocked and tree surgeons baffled,’…BBC Two’s documentary series Nature’s Weirdest Events suggest it may happen more often than you think.

Australian Chris Wharton was among those who revealed their shock at seeing a tree apparently pouring blood after he had cut it down, admitting he had ‘the shock of his life’.

‘I do not understand why this tree has apparently blood pumping out of it,’ he said, ‘It was the strangest thing.’

And presenter Chris Packham added that it was by no means an isolated incident, with reports of ‘bleeding trees’ occurring across the world and everything from disease to ‘the supernatural’ being blamed.

The good news is that there does seem to be an explanation for the weird goings-on – with rising sap in the springtime apparently responsible.

‘The sap is at high pressure until the leaves open and begin to evaporate the water, any injury releases this pressure,’ Packham explained.

‘This apparent ‘bleeding’ can look distressing, but it may be the tree’s way of trying to heal.’

(ack: caroline westbrook/Metro News of June 19,2014)

In ancient Greece man had no understanding of the forces of nature that assailed his everyday life. He did not have a conception of a single universe and his own reality was ‘ a confused republic full of warring forces.’ According to Fustel d Coulanges he prayed to them and worshiped them;he made them his gods.’  Since man acquired a scientific temper much of his world around him also became orderly. Think of it as Orpheus with his music quietening the wild beasts. He could play music notes arranged to create harmony. He merely settled their untamed nature in harmony with his own art. Science is like Orpheus. A scientist of the Medieval period could not have dreamt up Spooky Science or quantum computing. Suppose an Alien could show man in the Middle Ages the working of quantum world would he not have considered it a miracle? Miracle in a way is a crossover of two different states of being where power of say Alien (in terms of Technology, mastery over multi-dimensional existence) is no match for man whose mastery is merely three dimentional in a 2D universe. (To be continued)

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Even though scientists have managed to quantify how much dark matter lurks in distant galaxies, astronomers have been hard-pressed to figure out how much of the mysterious stuff lies within our own.

But in a paper published in the journal Nature Physics, a team of researchers has managed to measure the amount of dark matter in the inner Milky Way, which could shed light on the structure and evolution of our galaxy, and perhaps of others as well. Dark matter is that mysterious stuff that accounts for 84.1% of the matter in the universe, while normal matter – all the stuff we can see, from galaxies to stars and planets and black holes and us – makes up a mere 15.9%. Because it doesn’t interact with light, it is completely invisible to us, and the only way to tell it’s there is by looking for its powerful gravitational influence on the normal matter around us. For example, astronomers are able to calculate how much dark matter is in far-off galaxies by looking at their spin. Basically, astronomers can tell how much mass is in a spiral galaxy by watching how fast it rotates. The faster the spin, the more massive the galaxy. And if they’re more massive, the galaxies should be brighter, too, because they should be filled with more stars. But astronomers noticed galaxies that were spinning really fast, even though they weren’t bright. If the mass causing these galaxies to spin so fast wasn’t from stars or gas, then what exactly was it? Scientists need to measure how much of it there is in a given galaxy in order to understand the behavior of galaxies and the large-scale structure of the cosmos. For distant galaxies, that’s relatively easy to do. Ironically, for the galaxy we live in, that’s a much more difficult measurement to make, said UC Irvine astrophysicist James Bullock, who was not involved the study. [Measuring] anything is hard when you’re inside of it,” Bullock said. “It’s kind of like trying to figure out what kind of house you live in without ever leaving your house.”

Our knowledge of the forces that in certain phases seem to go contrary to our expectations as well as helpful at times is woefully inadequate. We call it luck. If we were lucky to hit a jackpot only to be burgled of the winnings why call it luck? On the other side of the coin if we have been led through a short leash in our adolescence and in old age face with what little we have, in a happy frame of mind, what do we call those years of restraint?

In short when life negates your chances as well as compensates later on must owe to forces that are at play. These forces are such reason cannot adequately explain these switch off/on phenomenon. Reason is simple: We are too much involved as to be impartial. If we cannot measure the dark matter inside our galaxy we may as well consider it as a possibility. If one born is in a log cabin and suffers hardships reason may explain it as something owing to the way circumstances are. If the same person could finally occupy the highest office of the land how reason shall explain it? Taking a leaf out of nature one might say, hardship as necessary as to make one toughen up. It makes sense, does it not? If President Lincoln’s life is synonymous with slave question it might add an additional insight: Life of hardship made him sensitive to the sufferings of the slaves. But actual details of the life show he was not moved by the plight of the slaves as much as he thought slave question was a question mark in the democratic credentials of the nation. How can a nation be half free and half slaves? Indeed it is a matter of personal integrity that he dared to make a change knowing that he was a marked man. Life of a man is not to be really measured by superficial details of birth, death, honors received etc., but in what manner the life could make positive changes. (LATimes-science Now-Heart of darkness: Scientists probe dark matter near Milky Way’s core)

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