Quantum Quiz 2... for die hard physicists...

This is a VERY hard quiz for die hard quizzers set on my favourite subject, Quantum Mechanics and Relativity. This was co designed by me and Atharv Joshi




Rules


1) Googling is allowed, but the level is so tough that I doubt you'll even find the answers.


2) 10 questions


3) Answers in comments.


4) No discussing, please.




Okay?


3
.
.


2
.
.


1
.
.


GO!




1) _____ is by far the most common form of cluster decay where the atom undergoing the decay emits a certain number of nucleons (in pairs of protons and neutrons), leaving behind fixed number of nucleons.


2) It is a sealed system consisting of densely saturated vapours of water or alcohol. This is used to detect subatomic ionic particle, which, when moving through the vapours, condense them, leaving behind distinct trails. Name it, and it's inventor.


3) Which theory, often called the most successful theory of quantum mechanics, incorporates the elements of BOTH relativity and quantum field theory. It describes how light and matter interact, and is the only theory in which relativity and quantum mechanics are complementing each other. Also, name at least one of it's founding fathers.
Note: It is NOT the string theory, because the string theory isn't really a physical theory, rather a mathematical one.


4) Which physicist proposed the idea that, as on earth, Universes too have 'offspring', which have variations of constants from their parent Universes. Name the physicist.


5) You can cohere two particles such that they are in phase with each other. If you separate these by a large distance, even more than a light year, if you spin one particle in one direction, the other will IMMEDIATELY spin in the opposite direction, thus transfering random information instantaneously, irrespective of the distance, breaking the light barrier also. Name the process of cohering the particles.


6) According to the C symmetry of the universe, if the charge and spin of a particle is reversed, you get a form of matter which is known as antimatter. The principle of antimatter as we know it was put forth by whom?


7) This book, mainly addresses the story of quantum mechanics, as it unfolded from the discoveries of Planck, Einstein, Bohr, Schrodinger, Heinsenberg, Pauli, Dirac and about later additions by John Bell & David bohm. It also addresses the question of the nature of reality, and also about the Einstein Bohr debates. Name the book, and it's author (who's Indian born, living in Great Britain).


8) X, known for his eponymous law partly addressing the ultraviolet catastrophe had Y as his doctoral student. Y is best known for his discovery of a subatomic particle, upon which you depend to see this quiz. Y's doctoral student Z, made an important contribution to the structure of an atom, while his student A defined it using Planck's idea of the quantum, even introducing definite paths. Name X, Y, Z and A, some of the greatest minds known to both classical and quantum physics.


9) Which mathematician, in 1854, came up with a matrix defining the mathematics of what is today known as the string theory. Einstein, who came later, stumbled upon the same aspect of physics, but he worked out the physical portion of the problem, lacking in the mathematical bit. He was introduced to the work of this person, using whose theory, he built the four dimensional design of space time. This matrix was later used to unify the theory of relativity with Maxwell's equations in the Kaluza Klein theory. And then, expanding the matrix, the string theory was born. Name this person.


10) This Indian physicist has made important contributions to the string theory, and to thermodynamics, including the concept of entropy. Having done his PhD at Stony Brook University, he went on to work at Fermilabs and SLAC. AS of now, he works at the Harishchandra Research institute. Identify him.


Bonus Question for timepass:
"X, best known for his work, devising new theories on the cooking time of goose eggs, the braking speed of the Ford Cortina in an oil slick and the natural propensity for objects, when released in midair, to hit the ground, was also responsible for the propagation throughout the physics world of theories designed to anger fellow physicists. The 'Malicious Theories' are seen by some as aberrations, by some others as 'Easter Eggs' in his otherwise dull work."
The above is a description by the parody website Uncyclopedia of whom? PS, when you're done, you can have a laugh... XD


I don't really expect anyone to answer all the questions, but here's an idea of what to expect

8-10 > You really know your Physics, and are an upcoming scientist. Hats off.
5-7 > Excellent. You have a really vast knowledge of physics. Keep it up.
3-4 > Very good. You've got amazing knowledge.
1-2 > Good. You have read up on this. Keep working.
0 > Never mind. This quiz WAS very hard.

If you get all 10,  you're me!!! 

PS: All the above questions are based on what I have read, so I've not picked stuff out of the blue here. If you've read the books I've read, you'll hack this.

Cheers!!!


I'll put up the names of those who get it.

The World's Greatest Woman

There is one woman
Who's been there for me
Since before I came into
This world to see.

She held me within her
Nourishing, nurturing, growing
For forty weeks, I was protected
Within her womb, not knowing.

The pain she bore to see me through
And open my eyes to the world.
And visualise for the very first time
The colours of the world unfurled.

She saw me through my ages
She taught me with great skill
She held my hand while I walked
And fulfilled my every will.

She taught me my first words
And number, oh so many
She cultivated in me an intuition
So accurate, so uncanny.

She bore with my silly tantrums
Through my teenage years
She wiped away with a loving finger
All my disappointed tears.

She tutored me with patience
So great, as yet I still wonder.
She strove so hard, and washed away
Every naively committed blunder.

She raised me with such hardship
Yet she gave me so willingly away
To my husband with such a sacrifice
With tears on my wedding day.

She stood besides my bed
In the hospital in which I lay.
Screaming in excruciating agony
Gentle yet firm her hand would stay.

And then she took into her stride
My little one, my child
Whilst I was away at work all day
And raised it up so mild.

She was always there by my side
When I needed her, or not.
Yet I never really said thank you
Althought it was always in my thoughts.

And now it is far too late
I stood with tears down my cheeks.
While she lay in a hospital bed
For perhaps her final weeks.

Then she turned towards me and spoke
With an obvious great effort.
She said, 'Don't cry, my dear child,
I cannot bear to see you hurt.'

And then I took her into my arms
And whispered at last that day
'Thank you so much, I love you, ma.'
Then, smiling, my mother passed away.

Mangesh Sonawane

When the sun will finally die...

Stars do not live forever. They live for billions of years, but not forever. The sun, too, is a star, and will eventually die.

Let us look at the Sun's resume. It is a middle aged star, at 4.5 billion years, and has 5 billion years more to live. It is a type G, yellow star, second or third generation, head of the Solar family. It is located in the Orion Arm of the Milky way galaxy.

How will the Sun die?

The sun is small, and will one day burn out all it's hydrogen supply. In the process of fusion, hydrogen is converted in to the heavier helium, and the extra proton mass is released as energy. Hydrogen, being lighter than helium, will rise to the outer layers, while helium will sink towards the centre. Eventually, the sun will run out of it's hydrogen, and start burning helium. When that ends as well, the outer layers will expand, and cool in the process. The star will become what is known as a Red Giant star. When the core collapses under it's own gravity, the outer layers and most of its mass will be shed in a beautiful display called a Planetary Nebula. The core will compress the helium at the center, and it will fuse to form carbon, which releases energy. At this stage, the star is a white dwarf. It is extremely dense, and slowly burns of its fuel, until it will slowly become a hunk of black nuclear matter floating in space.

This explanation can be better explained in a much more concise manner at

http://www.enchantedlearning.com/subjects/astronomy/sun/sundeath.shtml

Death of a Black Hole

This is a very Frequently asked question...

How do black holes die?

Well, some people think they last forever, and they're very nearly right. Black holes do die, but it is on a timescale of billions of years. No one has ever seen a black hole actually die, but astrophysics Stephen Hawking has proposed a theory about black hole death.

Black holes aren't black at all. In fact, they constantly emit radiation in the form of small virtual particles that are born in pairs out of photons, i.e. particles and antiparticles. At the event horizon, there is a sort of gravity well, which seperates the innards of the black hole from the outside. At this point, the energy is sufficient enough for the photons, or energy packet (also called quanta) to 'condense' into matter. Since the law of conservation of mass and energy is maintained, the particles have to be each others' anti selves.

Mostly, these particles do not last more than a few millionths of a second, quickly annihilating each other to form photons again. This is the actual Hawking radiation, the emission of photons by such a physical reaction. Unfortunately, this radiation is much too faint to be detected by even the most powerful telescope on earth.

But sometimes, it doesn't work out so well for the particle. They do not get to meet with their other halves. The anti particle gets whisked away beyond the event horizon, falling down the intense gravity into the object's core. The other particle is left partner less, and wanders off alone. Since it has a positive mass, it has a positive momentum and it can escape the gravitational field of the black hole (mind you, the event horizon is the point of no return. Anything outside that can and will escape).

The antiparticle goes and annihilates with a positive particle at the black hole's core, thereby reducing the mass of the black hole by one particle.

So what happens then?

Billions of years later, the mass of the black hole drops sufficiently to fall beneath the Chandrasekhar limit of 1.44 Solar Masses. At this stage, Pauli's exclusion principle kicks in. The particles, that have been oppressed and crushed into this tiny little space for billions of years by their own gravity, explode outwards violently. The energy released in this explosion is phenomenal. It could blow away half of the galaxy in which the black hole resides. Let's just say that if the Black hole at the centre of a galaxy a few billion light years away exploded by this method, when the light eventually reached us, it would make our nights as bright as day. That is the awesome power of an exploding black hole.

Will we be able to see one any time soon?

No. Like I said, black holes don't live forever, but they come very very close. If the theory is correct (and so far, it has never been disproved, and all evidence seems to back it), it'll be a few billion years (few hundred billion years, actually) before one does die. And even then, depending on its distance from us, it'll take even longer for the light to reach us. But, as you know, Earth isn't gonna last more than 5 billion more years, thanks to our daddy, the Sun. It's gonna become an old star, expand its size till it engulfs all four terrestrial planets (Mercury, Venus, Earth and Mars) before shrinking into a tiny white dwarf that will eventually cool off to become a hunk of helium floating in space.

More on this cheerful topic of the Earth getting fried next time... Tune in to Young-Geniuses.

Big Bang continued...

Another reason why the Big Bang is a plausible theory is according to the CMB radiation observed by Arno Penzias and Robert Wilson in 1964, for which they rightfully deserved the Nobel Prize in 1978.

With a traditional optical telescope, the space between stars and galaxies (the background) is completely dark. But a sufficiently sensitive radio telescope shows a faint background glow, almost exactly the same in all directions, that is not associated with any star, galaxy, or other object. This glow is strongest in the microwave region of the radio spectrum. At first, Penzias and Wilson thought it was an error, and even cleaned up the telescope of pigeon droppings. But then, when the glow persisted, they realised that it had to come from the Universe itself, and was almost exactly the same on all sides.

What is CMB radiation?

CMB radiation stands for Cosmic Microwave Background radiation. It is the after glow of the Big Bang, the residual energy that was released during the moment of creation.

But how is this related to the Big Bang?

The Universe is vast, far greater than what we can observe with even the most sensitive, powerful telescopes. The CMB radiation observed is almost equal from all sides. That means that the residual energy is more or less evenly spread out all over. But since nothing can travel faster than light, that means heat can't either. This implies that if the Universe was always this big, then the heat wouldn't have enough time to radiate in all directions equally, leading to HUGE holes in the detected radiation.But it is all even. That means that at some point of time in the past, the Universe was relatively close together, close enough for the heat to flow even to all points.We know the state of the Universe today, and we can calculate the distance the Universe must have had to have the heat flow evenly. Joining these two 'points', we can say with enough evidence that at some point of time, or the zero time, as physicists refer to it, the Universe was compressed into a zero space (not exactly zero, but the nearest possible). This then exploded, or expanded, or inflated, whichever you prefer, into the Universe we know today.

That, my dear friends, is the Big Bang.

Big Bang of Physics

Welcome to the Big Bang of Physics.

This is Mangesh Sonawane, and I'm here to introduce to you, in small ways, the huge and extremely interesting world of Physics. Of course, many of you know much about what I'm going to tell, but this is largely devoted to those who do not know much.

What is Physics?

Physics is the branch of science that deals with the physical realm of our Universe. The 'how' of things is associated with physics, and by extension, all the 'what','where','when' and 'why'.

I'm gonna start of with the basics of the Universe, and then move on to the Big Stuff.

What is this physical Universe?

The physical Universe is what we can observe in a very tangible way. What we can see, touch, tast, hear, feel and sense, all come under physics, or at least, analysis of the phenomena does. It includes everything from the largest stars to the smallest particle. From spacetime to th cosmic foam, everything comes under the physical Universe.

Let's start with the birth of the Universe.

How was the Universe born?

The most convincing and widely established theory is that of the Big Bang. So how did this theory come by?

Combining his own measurements of galaxy distances based on Henrietta Swan Leavitt's period-luminosity relationship for Cepheids with Vesto Slipher's measurements of the redshifts associated with the galaxies, Hubble and Milton L. Humason discovered a rough proportionality of the objects' distances with their redshifts. He discovered that with the increase in the distance, the redshift also increases. This led them to formulate the empirical Redshift Distance Law of galaxies, nowadays termed simply Hubble's law.

Redshift is a phenomenaon that is associated with the Doppler effect with light. As the distance between two points increases, the light becomes increasingly redder. This is because the expansion of space expands the wavelength as well.

If all stars and galaxies are moving away from each other, than means at some point of time they were all close together. Even further back, the Universe might have been cramped into a space smaller than an atom. At such a high density, all laws of Physics might have broken down. So anything that came before the Big Bang need not be considered.

Of course, the above explanation fits well with Euclidean space, which has three physical dimensions and one of time. But physicsits don't really like this theory, because it includes singularities, and physicists hate singularities because all laws of physics break down here. But the string theory has another view of space and time; that of Imaginary space. It is not imaginary in the general sense, but in the mathematical sense.

Black Holes continued...

Delving deeper into black holes after my last post, I think I'll need to add a few points here.

Black holes are formed not when the whole star has a mass of 1.44 solar masses. That is the mass of the collapsed core alone. The Chandrashekhar limit (1.44 Solar Masses) is just the limit beyond which the exclusion principle cannot support the core and it collapses.

Here's what actually happens.

If the mass of the star is 24 solar masses (henceforth, I'll refer to it as Msun) or less, about 7/8ths of it is blown away by the explosion. The core suffers the original gravity of the star made much worse by its existing radius. So it collapses. Now there are three possible endings for this sort of stellar death.

1) White dwarf:

This is a type of star that is extremely hot, and extremely dense. White dwarf stars have from 0.8 Msuns up to 1.44 Msuns. When its parents star is about to die, it expands into a Red Giant, blows off its outer layers, and collapses into this beauty. Like I said, extremely dense. A teaspoon of white dwarf material can weigh upto 5 tons on earth! Gravitational force on this star can crush you into a pancake in less than a second.
Unfortunately, they haven't got the pressure required to initiate nuclear fusion. So even though they may live for a long long time, they'll run out of heat eventually, and die.

2) Neutron star:

This is what results when a White Dwarf star has more than 1.44 Msuns, but less than 3 Msuns. These are born pretty much the same way. But because of the intense Gravitational force, even the atoms are squeezed together. The electrons combine with the protons in the nucleus to form neutrons. Now, the entire star is composed of just atomic nuclei composed almost entirely of neutrons. This is very dense, and by very, I mean very. A teaspoon of this stuff can weigh a million tons on earth. That's VERY VERY heavy.
Neutron stars live on almost forever. The curvature of space-time created by Neutron stars is second to only black holes.

3)Black Holes:

When a stellar core has a mass of more than 3 Msuns, it turns into the ultimate cosmic mystery; a black hole. Now I've explained about black holes already, so I won't go into much detail, but all in all, at the event horizon, the curvature is so strong that time actually stops. Even light cannot escape the gravity of this monster.
Needless to say, a teaspoon of this substance on Earth would literally swallow it up, along with half the Solar System. So don't try bringing a black hole to Earth.

Black holes don't live forever, but they come very very close. This is because of a type of radiation called 'Hawking Radiation'. More detail on this subject will be in the next post. But according to this theory, black holes constantly emit radiation. In the end, this radiation reduces that mass of the black hole to so low that it crossed the Chandrasekhar limit on the way down. Once it's less than 1.44 Msuns, it does not need to be contained in the centre, and explodes in a magnificent display. If Sagittarius A* (that's Milky Way's very own black hole) explodes, we won't need the Sun. It'll be so bright, it'll be 'day' even at night.