You cannot depend on your eyes when your imagination is out of focus

30It was perhaps one of the greatest discoveries in human history, when Maxwell suddenly realized that everything from the brilliance of the sunrise, the blaze of the setting sun, the dazzling colors of the rainbow, and the firmament of stars in the heavens could be described by the waves he was scribbling on a sheet of paper. The secret of light was finally revealed.

Do not look at mirage and look inside mirror…..28

A familiar example of the index of refraction is a mirage. If you are driving on a hot day and look straight toward the horizon, the road may seem to be shimmering, creating the illusion of a glistening lake. In the desert one can sometimes see the outlines of distant cities and mountains on the horizon. This is because hot air rising from the pavement or desert has a lower density than normal air, and hence a lower index of refraction than the surrounding, colder air, and therefore light from distant objects can be refracted off the pavement into your eye, giving you the illusion that you are seeing distant objects. Usually, the index of refraction is a constant. A narrow beam of light is bent when it enters glass and then keeps going in a straight line.

Music of the Cosmos

 Einstein once said that if a theory did not offer a physical picture that even a child could understand, then it was probably useless. Fortunately, behind string theory there is a simple physical picture, a picture based on music. According to string theory, if you had a super microscope and could peer into the heart of an electron, you would see not a point particle but a vibrating string. (The string is extremely tiny, at the Planck length, a billion billion times smaller than a proton, so all subatomic particles appear pointlike.) If we were to pluck this string, the vibration would change; the electron might turn into a neutrino. Pluck it again and it might turn into a quark. In fact, if you plucked it hard enough, it could turn into any of the known subatomic particles. In this way, string theory can effortlessly explain why there are so many subatomic particles. They are nothing but different “notes” that one can play on a superstring. To give an analogy, on a violin string the notes A or B or C sharp are not fundamental. By simply plucking the string in different ways, we can generate all the notes of the musical scale. B flat, for example, is not more fundamental than G. All of them are nothing but notes on a violin string. In the same way, electrons and quarks are not fundamental, but the string is. In fact, all the subparticles of the universe can be viewed as nothing but different vibrations of the string. The “harmonies” of the string are the laws of physics. 

Strings can interact by splitting and rejoining, thus creating the interactions we see among electrons and protons in atoms. In this way, through string theory, we can reproduce all the laws of atomic and nuclear physics. The “melodies” that can be written on strings correspond to the laws of chemistry. The universe can now be viewed as a vast symphony of strings. Not only does string theory explain the particles of the quantum theory as the musical notes of the universe, it explains Einstein’s relativity theory as well the lowest vibration of the string, a spin two particle with zero mass, can be interpreted as the graviton, a particle or quantum of gravity. If we calculate the interactions of these gravitons, we find precisely Einstein’s old theory of gravity in quantum form. As the string moves and breaks and reforms, it places enormous restrictions on space-time. When we analyze these constraints, we again find Einstein’s old theory of general relativity.Thus, string theory neatly explains Einstein’s theory with no additional work.


Since we cannot change reality, let us “change” the eyes which see reality…..

This is not a question about the meaning of life. That is whatever you decide to make it. Nor is this a purely metaphysical question, although it covers areas that have traditionally been the domain of philosophers. When scientists talk about reality they talk about tangible things – atoms and molecules, particles and radiation. But of course this is only the reality. Whether directly, through our senses, or indirectly, through our machines, we construct a picture of reality that resides not out in the stars and galaxies but within our heads. The old solipsistic chestnut about the world possibly being a figment of our imagination cannot ever be dismissed out of hand. Can the idea that the world, including ourselves, is a figment of someone else’s imagination. That said, the fact that we have managed to formulate physical laws which correspond so exactly with what we observe suggests that while ‘reality’ may be what we perceive, we are perceiving something that is very concrete indeed.

1For example we don’t know about the ultimate nature of the Universe. For a start, what is its ultimate cause? Twenty years ago cosmologists stated flatly that the answer was simply ‘the Big Bang’ and left it at that, but now scientists are starting to realize that this is not good enough. What was the bang exactly? Why did it bang and what happened before? Now we think of the Universe as a vast, 92 billion light year diameter sphere of expanding space–time driven by a mysterious
dark force field that we do not understand and populated mostly by a ghostly form of matter that we cannot see and cannot feel. Is this any less strange than those old folk cosmologies (The Earth sitting on the back of a turtle. The Earth as a disc floating in an infinite sea. The sky as a dome
through which the lights of heaven are visible as the pinpricks of brilliance we call the stars…)? And is this the whole picture? Or is “our” Universe simply a tiny mote on the back of a far vaster, far grander, appendage? 

A popular solution to the initial cause problem, and indeed all the questions we have about the nature of the Universe, is of course God. Across most of the world and certainly for a vast majority of people the existence of some sort of deity forms a perfectly acceptable bookend to all chains of inquiry about themselves and the world in which they live. It is certainly the case too that even in our so-called secular age many scientists continue to believe in God. Most scientists do not, any more, consider God to be a rational solution to the question of “How did the Universe come into existence”?imagesBut the Big Bang model is incomplete and there are many gaps. One important gap, albeit not with the model itself, is the general conceptual misunderstanding of the Bang as a gigantic explosion which threw vast quantities of shrapnel blasting into space, which later became the stars and galaxies. It is not entirely clear what happened, to say the least, but it is clear that the gigantic expansion of the universe that took place in the first millisecond after the Big Bang was an expansion of space–time itself, carrying the matter and energy embedded within it. It is better perhaps to imagine the Big Bang not as an explosion but more as the blowing up of a balloon. But there are other, more serious problems, as even the Bang’s most enthusiastic defenders will concede. For example, as we peer further away from the Earth we see galaxies as they were long ago. The light from very furthest objects that we can see left on its journey to Earth very shortly after the Bang, which is thought to have taken place 13.7 billion years ago. These very distant, very early galaxies are only a few hundred million years old, as we observe them, and should therefore be packed with very young, immature stars (our star, the Sun, is more than 4.6 billion years old). And yet many appear not to be: some of these very young, very distant galaxies look like mature galaxies full of ‘old’ stars. Then there is the fact that some of the stars we observe seem to be “older” than the Universe itself. What happened ‘before’ the Big Bang used to be seen as a pointless question, as it was considered that both space and time were created during the Big Bang; to talk of a “before”, therefore, is meaningless. But this view has been challenged, most notably by the Cambridge theoreticians.”Our” universe “floats” on a three-dimensional “brane” which moves through higher-dimensional space. The Big Bang, for which we have so much evidence today, was an event caused when “our” brane, after a period of contraction, collided with another, generating a great deal of matter and radiation. 

Insights into the very early Universe will also come from particle accelerators. As well as searching for dark matter particles, the collisions that will take place in the Large Hadron Collider in CERN will generate energies on a level similar to those seen in the Big Bang. 2The grand swoop of lights we see on a clear night sky is impressive enough; knowing that all those twinkling lights are not only a mere tiny fraction of all the stars out there but in addition that all the stars together possibly form just a small part of what is, is humbling beyond belief. The question of reality and what it is has been asked by philosophers and theologians for centuries. Now the baton has passed to science. It remains to be seen whether experiment and observation will end up enlightening us any more than the elegant reasoning of old……..

barcelona sky

I sometimes invent reality, so that I’d have somewhere to spend the night….

imagesTime makes our lives. It is the key to how we perceive everything, from the ticking of our own minds to the events which mark our passage from birth to death.The true nature of time continues to elude us. Physicists have made huge strides in the last century or so in the way we think about time, but as to what it is exactly we are not really any wiser than the Ancient Greeks. Plato, after all, thought time was an illusion. We talk of time ‘flowing’, but flowing through what? At what speed does it flow and why? And what is the ‘substance’ that flows? Time throws up all sorts of paradoxes. You can use the existence of time, for a start, to prove that nothing is real. The past is as dead as those who no longer live, no more real than your dreams, right? And the future has not happened yet. So all that is to come is, again, imagination. All that is real, therefore, is that infinitesimal sliver of time between past and present, which of course amounts to nothing, because as time never stops that sliver has zero thickness. So, time is real, but nothing else is.

What science has always been happy to do with time is to ignore the philosophical horrors it throws up and just get on with measuring it, giving it a symbol and plugging it into our equations, represented by a nice little letter, like t, doing its job, oiling the clockwork of the spheres. Time is a fundamental quantity, meaning that it cannot be defined by reference to
any other quantity. We can only measure it and use time to derive less fundamental quantities. A change in velocity over time gives us acceleration. Einstein showed us that the pull of gravity and the tug of acceleration were equivalent. Indeed, Einstein went on to show that ‘space’ and ‘time’ are really different sides of the same coin. Before Einstein, it was thought that space was filled
with an invisible medium called the ether, waves in which carried light and other electromagnetic radiation just as air carries sound. But in Einstein’s relativity, the old ether was abolished and
replaced by space–time, a sort of conceptual super-ether, through which motion and the attracting force of gravity can be plotted.

Unlike quantum effects, time is something we perceive directly. We have memories of the past but not of the future. Neither the future nor the past are ‘real’ in the sense that they are accessible and measurable, but one seems to have a privileged position over the other: the fact the past has ‘happened’ gives it a reality denied the future. Time as a fundamental quantity seems to be intrinsically linked to our conscious perception of the world.images (1)

The idea that time is just the fourth dimension of space, one which we have a special interaction with through the offices of our conscious minds, is an attractive one. And clearly there is an element of truth in it. In our everyday experience, time flows, as we flow with it. In classical physics time is frozen as part of a frozen space–time picture. And yet there is as yet no agreed upon
interpretation of time in quantum mechanics. What if a future scientific understanding of time were to show all previous pictures to be wrong and demonstrate that the past, the future and even the present do not exist?

The distinction between past, present, and future is only a stubbornly persistent illusion….

Quantum mysteries

1Schroedinger, Erwin! Professor of physics!
Wrote daring equations! Confounded his critics!
(Not bad, eh? Don’t worry. This part of the verse
Starts off pretty good, but it gets a lot worse.)
Win saw that the theory that Newton’d invented
By Einstein’s discov’ries had been badly dented.
What now? wailed his colleagues. Said Erwin, “Don’t panic,
No grease monkey I, but a quantum mechanic….

Einstein played a leading role in the development of the ad hoc old quantum theory, but he was uneasy about it. Heisenberg’s mechanics seemed abstract to be a true representation of reality. On the other hand Schrodinger’s wave mechanics looked promising until Born came along and spoiled it with statistical interpretation….Einstein had been happier ….- You believe in the God who plays dice, and I in complete law and order in a world which objectively exists,and which I in a wildly speculative way am trying to capture…. Bohr responded to Einstein’s ideas with a series of brilliant arguments known as the “Copenhagen Interpretation” .
Einstein wasn’t the only physicist to object to the implications of quantum theory.Schrodinger initially believed his wave mechanics would return physics to an era of continuous differential equations and waves.De Broglie tried to retain some physical reality of wave – particle duality….
It’s wrong to think that the task of physics is to finde out how Nature is. Physics concerns what we can say about Nature. 2
Quantum theory leaves the future open and inhibits our ability to know the past.It’s hardly surprising that this radical shift in the interpretation of physical reality should shock and surprise physicists.Schrodinger was disturbed by these ideas and he published the amplification from quantum events. The Schrodinger cat thought experiment is the most famous in quantum theory.He involves a conscious creature – cat, whose fate depends on the detailed way in which the wavwfunction collaps. The cat must “exist” in a superposition of live and dead states until the experimenter opens the box and observes the state of the cat
incredible – who’s create the world? 

Radioactive atom with 50% chance of decay in 1 hour
A cat is confined in a windowless box for 1 hour.The boh contains a fiendish apparatus that will administer a lethal dose of poison if triggered by decay of a single radioactive atom.
After 1 hour Schrodinger open the door of the box and see one of two possible outcomes
– atom has not decayed, cat still alive
– atom has decayed, cat is dead
The idea that the atom is in a superposition of decayed/undecayed states and the cat in a superposition of live /dead states prior to observation is disturbing.
However if superposition doesn’t take place it’s impossible to explain the appearance of interference effects in related experiments. Einstein couldn’t accept that quantum theory meant the end of an objective physics reality. He thought that quantum theory applied only to the average behavior of ensembles of particle, and wasn’t complete theory of the behaviour of individual particles.

Statistically speaking, the cat (goes the joke),
Is half a cat breathing and half a cat croaked.
To some this may seem a ridiculous split,
But quantum mechanics must answer, “Tough shit”..

Why Atoms?

atom1I’ll be the first to admit this
is a bright but haunted age
I just don’t know now
now I just can’t say hey hey
And you keep slipping down the surface of things
I just cant take it now,
I just cant wait for more when you get down
down to the sub atomic part of it thats
when it breaks you know,
thats when it falls apart oh caveat emptor,
open the atoms core ….

the glory of the atom
begs a reverent word
the primary design
of the whole universe
yes, let us sing its praises
let us bow our heads in prayer
at the magnificent consciousness
incarnate there

the smallest unit of matter
with its orbiting electrons
echoing off the solar system
like a hawk in the hills at dawn
the smallest unit of matter
uniting bird and rock and tree
and you and me…

The idea that all matter is made from a combination of a small number of simple things goes back to the beginning of recorded history. The ancient Greeks proposed several unifying ideas one of which was a fairly atomic theory, attributed by the poet Lucretius in his poem “On the Nature of Things”.
“No rest is granted to the atoms throughout the profound void, but rather driven by incessant and varied motions,some after being pressed together then leap back with wide intervals, some again after the blow are tossed about within a narrow compass. And those begin held in combination more closely condensed collide with and leap back through tiny intervals….”
The name atom derives from atomos, meaning “uncuttable” a reflection of the Greek belief that all matter consists of an arrangement of few kinds of fundamental indivisible particles.
In the 19th century the atomic hypothesis developed into a powerful explanatory system, particularly with the work of Maxwell, Boltzmann, and Clausius. Some physicist took the atomic theory very seriously and assumed that atoms themselves are real, as Thomson – Lord Kelvin put it an atoms is”a piece of matter with shape, motion and laws of actions, intelligible subjects for scientific investigation..”
Various models were proposed for the atom including W. Thomson’s vortex rings in the
ether and J.Thomson’s “plum-pudding” model in which negative charges were embedded in a diffuse positive material. Two key discoveries led to the more familiar planetary model.
Model of the atom evolved through
– Rutherford’s nuclear atom
– Bohr’s quantised atom
– Schrodinger’s wawe-mechanical atom.
The electron (discovered in 1897.) was the first subatomic particle.It was discovered in a particle accelerator (Crooke’s tube).
The idea that nuclei might contain a neutral particle was considered by Rutherford in the early 1920s.Rutherford suggested many ways in which the neutron might be formed or detected including the idea that hydrogen atoms might collapse to neutrons as electrons fall into the nucleus, but the crucial obsevations that led to descovery of neutron were made by
– Walther Bothe and Herbert Becker in 1930 – they are noted that beryllium emits a very penetrating nuclear radiation when alpha particles are fired at it
and the
– Joliot – Curies in 1932. discovered that this radiation could eject protons from paraffin…