Falling Masses, the Big Picture.

This lecture note will make your life ten-fold easier in the scope of the problems it addresses. Consider it a talisman. I discovered this a couple of weeks ago when I was solving these problems for my own conceptual understanding. So I waited till I can completely enunciate the big picture. When I confirmed that its valid for all the following problems I made this note and sharing with you.


There is nothing there.

According to classical mechanics — from 400 year old knowledge of physics, space and time have been considered to be separate entities but not fundamental. Space and time were not considered fundamental quantities as these parameters did not have the mandate to change physical laws of nature. They were merely the tools of the mind or the more aptly the conscious mind. They help us visualize but not dictate what ought to happen.

Gravitational Anomaly.

Gravitational Anomaly: (asked by a student for very simple explanation)

Basically it means the new laws of physics known as Quantum Mechanics invalidates the sanctity of nature’s principles or laws (that is QM brings exceptions to the validity of the physical laws of nature itself)

Let us discuss this in simpler ideas from the basics only.

Remember the most basic physics, that of principle of conservation of energy and the principle of conservation of (linear) momentum.

In the more rigorous formalism of physics these two principles emanate (that is derivable) from two ideas of symmetry. In-fact every conservation principle of physics are manifestations of a corresponding principle of symmetry and vice-a-versa (also every symmetry must correspond to a conservation law). This general idea of connection between conservation laws and symmetry is collectively known as Noether’s theorem and is a central underpinning in all of today’s conceptual physics.

Inherent ability = difficulty * accomplishment.

All of Physics is this “Inherent ability = difficulty * accomplishment”. Thats just intuitive but can easily be seen to correspond mathematically with the Principle of least action.

First the edifice: whats the problem? The problem is given you move in straight line when every direction is same around you, which direction will you chose? While you are waiting for a good answer from astrologers intelligent people already give a good hint. Think you have some inherent ability which is fixed.

fixed: which changes only if estimated wrong.

That inherent ability is actually action. Accomplishments are adjusted for difficulties, you waded through a swamp 5 meters you would have accomplished in sand 8 meters with that given inherent ability called action. Because action is abstract we have been sticking to time and path-length, but they are not as fundamental, they are merely specifics.

A c++ code for calculating pi value.

Finally I am successful in calculating pi value — less than 0.3% error, by using random number generation. Although my computer needs some fixation on its compiler or path definition etc, there are very good online compilers which helps in testing and running c++ codes: try the given link.

Computing the value of pi using std::rand()
Enter number of trials: 10000
Enter number of random (x,y) points per trial: 10
pi = 3.14376 +- 0.00519107
average – exact = 0.00216735
CPU time = 0.004027 secs

Here is the code I found by searching a good deal on the web. Yes I did tinker around but only because my own compiler (Turbo C++ on windows 10, 64 bits) was throwing some exceptions on the included headers.

using namespace std;

double pi_estimate(const unsigned long points)

Addendum to Coriolis Force; Definition of Centripetal Force.

We need to understand first that Force can be categorized into two types. One is called tangential or collinear force. This component of the force is always along the direction of motion and changes speed of an object. It can change direction once the velocity of the object has become zero. Its NOT centripetal force. It can never make an object go in a plane or 3 D trajectory, as the motion is limited to only one dimension. The object can only go back and forth.

Now look at the other component. Its called a radial force. Its always perpendicular to the direction of motion. This force is called centripetal force, always. Note that its different from what we call central forces.

In consequence, both tangential and radial forces can be central.

Quantum Entanglement .. a short primer !

This fact is inherently, nothing but the concept of Quantum Entanglement. Unlike classical particles which are completely independent of each other the quantum sized objects are not. For physical intuition they are at a very small and subtle level intertwined with each other as if threads are kind of tied onto each other. We can-not toss an electron because the whole concept of one electron completely independent of all other makes sense only when all other electrons are not interacting because they are arbitrarily far away.

This year’s Nobel prize in Chemistry.

What happens when some UV falls on biological molecules? (or any kind) some of these molecules like the wooden pole absorb the energy and there still remains energy which they can emit as visible light. So the UV light kicks the molecules and the molecules in turn emit visible light. This implies that the UV wavelength that the molecules absorbed energy at are very small compared to the wavelength at which they emit visible light. This is always the case.

When we say some materials are fluorescent it means they absorbed higher energy and emitted lower energy radiations of colorful light.

But this has a great deal of application apart from its theoretical interest.

The angular parameters of celestial mechanics !

Define an Hour Circle.

Its a bit tricky to define some astronomical parameters and not run into innocent looking misrepresentations of facts. One needs to cool his amber more times than there are parameters, then one gets a feel where and how to begin and give a good description.

Hour Circle is a GREAT Circle, on a celestial sphere ** that, at the same time, passes through one of the celestial poles. Hence it passes through both of the celestial poles*.

A great circle is a circle that passes on a sphere, so that its radius (or diameter) equals to the radius (or diameter ) of that sphere.

If the great circle goes through one of the poles (– so both poles as an imminent condition of this definition) its also called a meridian and this circles’s angular reference wrt one of all possible meridians is called a longitude angle, or simply longitude.

Star Motion, an interesting star concept.

To budding astronomers.

A difference between true velocity and proper velocity. Proper velocity (proper motion) is the motion of a star apparent to the center-of-mass of the solar system. That is, how fast any object (a star) is moving wrt the sun’s position. (in terms of its center-of-mass)

So if a star is close to sun, its true velocity might be as much as it is, but proper velocity can be larger. Proper velocities are often larger when stars are closer, an useful fact in Astronomy.

(How proper velocity is eg useful in Astronomy, should be a good essay type question in Indian University exams, in the course of astronomy, but rather its more useful to remove essay type questions from Exams of University and such essay should be written by students as blogs, and the best blogs can be rewarded, Change should be brought to our education system by innovative thinking and not just by lecturing on outdated spiritual discourses)

Stars and Fate.

Astrology is the blind belief that stars change our fate — pun; like the blind belief wives change our personality. This is where Physics becomes a paraphernalia of whim, cultivated over the ages, to bring solace in seeking ignorance as a means of existential glory.

I just checked some scientific terms, in regards to how they have been made to work like paraphernalia to produce different astrological system. I was not shocked that Indians have kept advanced strides in one branch of knowledge — or the lack-thereof; Astrology.

Guess what? Hindu Astrology is a Sidereal Astrology, hence much advance than Western Astrology, which is a tropical astrology. This we have often taken boastfully, to mean that Indian science is advanced and far-reaching, even from the times of Vedas, but the simple facts — of my conviction, are; we have been manipulative from a very early time in our civilization’s evolution.

We just took science to produce religion. We also took religion to produce myth, and myth to produce social customs and took social customs to downplay science. Why else is “western” science advanced and we are merely a laggard participant in its various glorification.

— Of-course I don’t have words of solace to those who disagree, if like kids we assign ourselves the fancy of winning every sports, that we do not even take part in, because our parents will succumb to that whimsical demand of ours, it wouldn’t work towards science, here we have to work nonetheless, take part in each and every detail and each and every aspect, its not sufficient or even necessary to just downplay the impact of criticism.

A new optimization parameter in a statistical sample !

It reflects the quality scope of the citations. Its the total percentage of a citation that goes into defining a particular citation index. Let me call it q-index therefore (q for quality)

See this example.

My h-ind is 60. So total (minimum) citation it accounts for is 60*60 = 3600. My total citation is 12215. So my q-ind is 3600/12215 = 29.47% Or 29.47% of my total citation were important for this parameter. Hence my q-index is 29.47. In this way if someone has 500 total citation with h-index 60, he has a much better q-index than mine, because more of his paper are highly cited

The quality of a scientific paper … A casual reposition.

The quality of a scientific paper are not ZERO if citation is zero. Perhaps we need to define two parameters, quality and significance of scientific communication. Quality; a well done research in the best traditions and methods available. Significance; the outreach of the paper to bring effect into others work and others understanding toward the subject matter.

While there will always be a downside to both parameters, citation reflects the significance (and quality as much as it correlated to significance) of a paper.

Why is the helicity for a mass-less particle Lorentz invariant?

Result; now that photons are mass-less, their energy, momentum, speed, etc are no more variables, in the sense of arbitrariness. They are constants, taking only a few values, but constant in a given situation. But other particles have these properties; arbitrary. So electrons energy and momentum are not fixed, but arbitrary.

But as long as we are considering only elementary particles (that is, we are in a Quantum Zone) eg, electrons, protons, photons, and not nutmegs, soccer balls and airplanes and satellites there is another quantity that is of important consequence that is constant. Spin; whether a mass-less particle or not, spin has the same magnitude for them. that is spin is same for photon, its always 1. Spin for an electron is always 1/2. Spin for proton is always 1/2. Its for this reason photon is called a Boson**. Any thing with spin, 0, 1, 2, etc will be a Boson. Anything with spin 1/2, 3/2 etc will be called Fermion.

Ideas that changed our notion about the Universe.

1. Aristotle Fallacy; A notion that objects need force for their movement. It contradicts the idea of inertia. Newton corrected this by introducing the first law, things continue in their state of motion, a quality called as inertia, without requiring force and the motion changes due to application of force.

2. Earth is flat; that there is a boundary where you fall off its edge. [I am not going to explain or tell you how and when we found this was a horrendously hilarious and misleading notion we had. But it might have been used in the past by parents to discipline their teen-age kids. Don’t go out, you will fall off earth. That would have kept them in check.]

3. Rotational Dynamics; Earth is accelerating in a near circle in addition to about itself, so additional forces are acting that changes our observation about the world. Newton tried to understand this (not successful) in his last days, by rotating a bucket full of water, his laws could not explain the effects observed. His laws needed to be modified slightly. The same thing makes objects feel weightless by a given amount if they are accelerating towards a gravitational field (eg merry go round, satellites) This is the basis of many works of Einstein. First came Mach’s Principle which says observations made from objects that are accelerating in circular paths are to be corrected by fixing frames of references to stars that are so far away that the rotational motion is neglected. [if you shake your head while looking at stars and shake your head by looking at nearby objects such as a light post, evidently the light post shakes more and the stars less]. This helps in correcting observed phenomena from earth. Earth moves at 30 kms/second wrt sun …

Nature of photons.

Also (without any direct theoretical connection, but correlation through reality of nature)
3. Photons are classical only in the sense that we perceive light only when photons are produced in large numbers. So large that the laws of the small do not incur large errors because they are in large numbers. Statistically the errors are well understood and eliminated. But when they are produced in very small numbers we can not deduce their laws a priori. [which is why Quantum Mechanics was discovered only in 1920s and not in Galileo’s time, In his time the macroscopic behavior were understood and microscopic laws can never be produced from the understanding of macro scope just like a particular individuals attribute can’t be found from a large number of individual’s group attribute]

Uncertainty Principle Again.

2. The object can be a large object, eg say something whose picture you are taking. But as explained above its not the energy of the object (or momentum) which is directly coming into the problem. That would be an added degree of concern if the object is moving with certain velocity, a reason why pictures are blurred. Because motion of objects introduces additional energy-time-momentum-position variables and their corresponding uncertainties. For the argument of the above problem one can imagine the large sized object, lets say a bird, is standing still on a tree while its picture is being taken. In that case if the wavelength of the light [few 100 nano meters = 1/10th of a micrometer] is used (eg in a digital-camera) the corresponding accuracy of the light will be less than micrometers. You can take a very sharp picture of the bird, which is lets say 6 inch long. But when you zoom in to a large degree, the inaccuracies will show up. [in this case how to see a micrometer level image? Is a computer sufficient to show us the uncertain edges of the pixels?] If the wavelength (here visible light) is so small, evidently by de-Broglie relationship, momentum or energy of such light is very large. But its not as large to disturb the feelings of the bird. The bird doesn’t have a problem with visible light, and such energy does not disturb its position or energy or any thing so to say. So while Quantum Mechanics is valid, we are accustomed to say this is a classical mechanics situation. To say QM is invalid is incorrect. To say QM is understood to be valid is a knowledgeable position.

Review of Gravity, the movie, discussions.

A discussion on Space movie Gravity, which I saw recently.

I remember one fact, that concerns, Physics, the roughly 50000 miles an hour (correct?) speed of ISS level debris that was coming, it set me thinking, are they violating the Relativistic Laws? For a while, and then I realize its per hour, not second, (that later would be grossly incorrect, 50 K miles / sec would violate Relativity certainly) that comes out to be 20 km/sec and thats perfectly enough close to what sort of speed, earth, moon, any satellite are typically found with, in our Sun’s Gravity. (in free fall) Even Rocket’s launching requires escape velocity. 11.2 km/sec. So they have clearly done their research on the Physics, as far as I could get in that moment.

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