Physics Discussion Thread

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Amber G.
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Re: Physics Thread.

Post by Amber G. »

vina wrote: ... However, as the driving frequency builds up towards the resonant frequency, the amplitude starts increasing very rapidly. .
I am simply interested in quantifying 'very rapidly' in this case...practically speaking, what does it mean? milliseconds? seconds? hours? years?
What is meant by swinging initially? (If the amplitude is less than 1mm, 1cm, 10cm?)
To get it moving from rest. Lets see how it happens (assuming perfectly still air), the initial motion is due to the Bernoulli effect/Venturi..
So once the bag gets "perturbed", the next step is to drive the oscillations with exactly timed forces (like in a clock with the escarpment and spring mechanism), so that the amplitude starts increasing and builds enough to knock the bottle over. This can happen in "a wink of an eye", ie a couple of oscillations to knock the bottle over.
Again, I am not sure what you mean by "initial motion" in practical terms? Suppose it is swinging with an amplitude 1 mm (or 1 cm).. do you mean to say that it will reach amplitude of 1m within "couple of oscillations"
? (that is, say less than a minute?) :?:
Sure, as you said, you can time it with the pendulum, if you wish.. but isn't the frequency fairly constant ? .. I mean even at 15 degree swing the variation is less than half a percent (of the order of .02 second)
Remember, the simple harmonic motion (SHM) of the pendulum is due to a LINEAR APPROXIMATION, so that it it fits in the form of F = -kx , which is the generic form of the SHM equation that gives the answer in terms of a sin and cos function. That approximation is essentially for the pendulum type problems sin(theta) ~ theta ( the restoring force is -ksin(theta), which gets approximated to -k*theta) . That approximation holds for very small values of theta (upto 5 degs I think), beyond that, it goes to Pakistan very soon
If one really does an experiment, one would find that it is a fairy good approximation of SHM..Even at 30 degrees swing (on both sides, that is 60 degree total swing) the variance in time period is about 1.7% (.017).. At 15 degrees (as said before) it is about 0.005 (T))..
(Rule of thumb, less than 1% -- for swing up to 21 degrees)

You do not get too far off, if you just use elementary equation .. and use the power series (sin x = x -x^3/6 etc... to get)
T = 2*pi*(l/g)(1+ (1/16) (theta)^2+ next term will be 4th power..
(Or little better approx, as given in elementary books .... (1/4) (sin (theta/2))^2))
(For perspective, this of the same order or smaller than errors introduced by, say air currents , variation in the value of g (if one uses the same pendulum at different locations).. ityadi..)

Important point to note: Historically (way back in 17th century or earlier)..simple pendulums (essentially very simple devices) were good enough to give accuracy of 10-20 seconds seconds per day...later they became more precise, quite accurate, in fact before quartz clock (1920's) , considered as the most accurate instruments to measure time.
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Re: Physics Thread.

Post by Vayutuvan »

ramana wrote:AmberG, What is this Hessian operator? Where is it used and what are its advantages?
Ramana garu

If I may, it is the second derivative analogue for a scalar valued function of several variables and is a matrix whose entries are defined to be

Let $H$ be the Hessian matrix for a function $f(x_1,x_2,...,x_n)$ then (in latex mathmode)

$H_{ij} = \partial^2 f/\partial x_i \partial x_j$

Or if one reads it aloud it would go something like "H sub ij is doh 2 f over doh x i doh x j".

It is very important in optimization (especially qudratic forms), finite elements and in general almost all of mechanics and engineering (i.e. applied math) and serves the same purpose as the second derivative in the single variable case. Usually in single variable case, one sets the second derivative to zero to find the max/min of a function. Similarly in multi-variable calculus, the Hessian is set to zero. Most of the times, Hessian is symmetric. If it is positive definite, then the function is convex and a global minimum exists which guarantees that any iterative method (for example steepest descent) will converge.

For further details of Taylor Series expansion look at the book Introduction to Applied Mathematics by Gilbert Strang as well as a more basic treatment in Advanced Calculus by Kaplan.

Since it comes up in several different areas, I am curious as to where did this come up for you?
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Re: Physics Thread.

Post by Amber G. »

ramana wrote:AmberG, What is this Hessian operator? Where is it used and what are its advantages?
See http://mathworld.wolfram.com/Hessian.html
or wiki:
See http://en.wikipedia.org/wiki/Hessian_matrix
This is simply the second-order partial derivatives of a function.
For example gradient (or Jacobian) is the first order derivative.

In one dimension - first derivative, in common language is called slope.
If one is on a mountain.. height of a point (scalar quantity) depends on its (x,y) location.. The gradient (direction and value of slope - a vector also depends on its (x,y) location) . ..Hessian is a tensor (and a function of (x,y) too) and is, roughly speaking, "curvature".. .. Day to day analogy could be to a , say , stress tensor which most engineers are familiar with when they study "deformed" objects...

(Tayol's expansion of a multi-variable function is similar to single variable function.. In the single variable function you have , for a small h ; f(x+h) = f(x) + h f'(x) + (h^2/2) f''(x) +...
In Multi-variable function, the expansion is similar to above)
Last edited by Amber G. on 07 Jul 2011 22:54, edited 2 times in total.
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Re: Physics Thread.

Post by ramana »

In my working life I get to sit in as maulana when mujahids come seeking moolah.

So one of them was saying that they use the Hessian on the image to detect the void (bubble or ellipse) by its curvature.

Now it makes perfect sense by taking the second derivative of the curve we know its concavity or convexity based on whether its positive or negative.

Thanks for the explanation.

So Jacobin for first derivative and then Hessian for second derivative?
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Re: Physics Thread.

Post by Amber G. »

^^^ Interesting.. you used "curvature".. very similar to the analogy I was giving..:)
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Re: Physics Thread.

Post by Vayutuvan »

ramana wrote: Thanks for the explanation.

So Jacobin for first derivative and then Hessian for second derivative?
When the function is scalar valued, then the Jacobian is called the gradient and is a vector, but yes, Jacobian is a generalization of the first derivative to vector-valued functions of several variables and Hessian (which is necessarily a square matrix in case of scalar valued functions, say electrostatic potential or temperature) is a generalization of the second derivative. Jacobian can be used as a linear operator to go from one set of coordinates to another set of coordinates. Jacobian need not necessarily be a square matrix, i.e. the transformation can be applied between spaces of different dimensionality. But if the Jacobian is square and has an inverse, then the determinant of the Jacobian gives scale factor when transforming n-dimensional volumes from one set of coordinates to another set of coordinates (say from rectilinear to polar or cylindrical etc.).
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Re: Physics Thread.

Post by ramana »

I lost you in the fourth sentence 8) But not to worry, I know what I dont know.

Younger days would have read up all the books and tried to understand it. Unfortunately miles to go before I sleep.
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Re: Physics Thread.

Post by Vayutuvan »

ramana wrote: Younger days would have read up all the books and tried to understand it. Unfortunately miles to go before I sleep.
Cool, My intention was not to be dense but since it comes up quite often just wanted to define it completely and unambiguously. The problem is that once one goes to more than one variable (and the next hump of going from > 3 variables), normal intuition would fail and the only way is algebraic if one doesn't want to be loquacious.
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Re: Physics Thread.

Post by brihaspati »

Well how about thinking of a small "square" on the "surface" - and notice how differently - if at all, a small vector will change direction by going along two adjacent sides across both sides of a diagonal of the square [go first along "x" and then "y" - and also first along "y" and then across "x"]? If the "rate" of change of directions ["slope"] are found to mismatch at the end point after going along the two paths, then surface cannot be "flat". This can easily be extended to higher dimensions.

This is the basis of the modern generalization. The Hessian is connected to Gaussian curvature, but then one needs to take the "volume" - that is determinant of the Hessian, and subject to further conditions on the gradient.
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Re: Physics Thread.

Post by Vayutuvan »

brihaspati wrote:Well how about thinking of a small "square" on the "surface"
Bji

Nice
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Re: Physics Thread.

Post by brihaspati »

^^^parallel transport :P Actually it may simplify the visualization, if we think of starting from one corner, and note the two tangents [in "x" and "y" direction"] and see how they change as the "x"-tangent moves along the "y"-side one edge, and same for the "y" tangent moving along the "x" side one edge [so they stand on ends of the diagonal facing the starting point]. If there is a difference - the surface must be "twisted" or "curved" inside the "square".
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Re: Physics Thread.

Post by Amber G. »

When the function is scalar valued, then the Jacobian is called the gradient and is a vector, .....
True but just to make it clear.. and intuitively practical (Continue reading if interested ..:) )

Jacobian [of a scalar field] is called gradient.
Hessian is nothing but Jacobian of gradient.

Practical examples are: Electric field (force on a unit charge - which is a vector - direction and magnitude) is gradient of Electric potential (which is a scalar).

Or gradient of height (two dimensional equivalent of 'slope' of a mountain - vector - magnitude and direction of the steepest path) is Jacobian of height (which is scalar).

If gradient/slope is constant (Hessian is zero), you have straight surface, otherwise it is curved in the direction depending on the sign of second derivative (or slope is increasing or decreasing)
****
To make matter a little confusing, some call not the matrix but the determinant (which is a numerical value - just a scalar) as Jacobian/Hessian

****
Mathmatica / wolfram and some math packages have these as built-in in their libraries, to make things easier for engineers as the computers can do the math without too much programming ... :)
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Re: Physics Thread.

Post by gakakkad »

Amber G. wrote:
SriKumar wrote:AmberG, your questions remind me of that book Physics for Entertainment by Yakov Perelman. I bought the first volume but did not buy the second one. If I can find it now, I'd pay 100 times the amount that I bought it for, back then..
The book is available here online:
http://www.archive.org/stream/physicsfo ... 7/mode/2up
:) (What is 100 times the amount you bought it for ? :) )

Any ones got a DOWNLOADABLE soft copy of this one ? I grew up with this. But I lost the book. An does not seem to be available in book shops any longer. There were many great texts from Mir publishers but can never find them anywhere.
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Re: Physics Thread.

Post by Amber G. »

GuruPrabhu wrote:I hadn't realized that the discussion had moved here. The explanation for U/Th not sinking is as Amber said -- U/Th are lithophile rather than siderophile (metal loving). This is seen in foundries also. If you take a large vat of molten iron, the U and Th impurities migrate from the bulk and concentrate on the periphery (mostly on top!). The core of the earth has two parts, a solid one and a liquid one -- the liquid is mostly molten Fe and Ni, which has expelled the U and Th.

There is some speculation that there is a concentration of U in the solid core also. If true, this may form a natural reactor. There is no direct evidence yet -- the numbers have to add. The measured *total* heat flow from the earth is either 31 TW or 44 TW, depending on the method used. OTOH, several calculations now agree that the radiogenic component (U/Th/K decays in the mantle) contributes 19-20 TW. There are estimates that the "core reactor" may contribute as much as 6 TW. All of this can be sorted out if planned large neutrino detectors get the go ahead.
Don't know if GP is still here to read this (or he became a victim of Bradmins' game) but neutrino detectors in Japan and Italy(Kamioka Liquid-Scintillator Antineutrino Detector and the Borexino) have confirmed, according to a recent article, that indeed there is fission going on.

More than half of 44 TW is from radioactive decay (+ fission in the core, confirmed by geoneutrino's). And yes about 4TW from decaying K40. Remember those bananas!

Expect a few news headlines regarding this in coming days..
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Re: Physics Thread.

Post by Amber G. »

xpost:
Physics Olympiad: Indian students win three gold medals and two silver medals at the 42nd International Physics Olympiad (IPhO).
Link:[url]http://mpec.sc.mahidol.ac.th/ipho2011/node/101[/url
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Re: Physics Thread.

Post by Amber G. »

gakakkad wrote:
Amber G. wrote:>>>AmberG, your questions remind me of that book Physics for Entertainment by Yakov Perelman. I bought the first volume but did not buy the second one. If I can find it now, I'd pay 100 times the amount that I bought it for, back then..<<<
The book is available here online:
http://www.archive.org/stream/physicsfo ... 7/mode/2up
:) (What is 100 times the amount you bought it for ? :) )

Any ones got a DOWNLOADABLE soft copy of this one ? I grew up with this. But I lost the book. An does not seem to be available in book shops any longer. There were many great texts from Mir publishers but can never find them anywhere.
Many such books seem to be available at amazon.
Also, as long as it is strictly for personal use, here is a pdf copy
Hope it is helpful.
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Re: Physics Thread.

Post by sanjeevpunj »

The speed of light in vacuum is the Universe's ultimate speed limit, but experiments in recent years suggested that single photons might beat it.If they could, theory allows for the prospect of time travel.Now, a paper in Physical Review Letters shows that individual photons too are limited to the vacuum speed limit.
Source:http://www.bbc.co.uk/news/science-environment-14289114
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Re: Physics Thread.

Post by ramana »

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Re: Physics Thread.

Post by devesh »

^^^
space travel is essentially time travel on a certain level. if humans ever find a way to do human spaceflight beyond the solar system and get a bird's eye view of the Solar system, then we have basically achieved time travel. when you return to earth, you will have aged less than the people who've lived here all along. if we do human flight to the level of taking a look at a decent portion of the Milky Way galaxy, then by the time you return to earth, there will be significant difference in the ageing that will be clearly visible. Einstein predicted it. and later confirmed by putting clocks on Space shuttles, which showed some lag time, when they came back to earth. Time Dilation.

as for breaking the speed of light, now that would be true time travel, in all its glory. except, in all likelihood, Humans will be extinct before we ever get anywhere close to achieving that. nobody even knows, if it's even possible to break the light speed barrier. protons come really close to speed of light, but don't touch it, or exceed it.
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Re: Physics Thread.

Post by sanjeevpunj »

^^^If one can approach the sun close enough in a physical body,one will become ashes, and the soul will return to earth to be reborn.This is the spiritual way to time travel, the bonus is you get a new body. 8) On a more serious note, The speed of earth around the sun is around 2/3rds the speed of light. We are already travelling so fast :) and we just need to hop onto a celestial body that is faster than this speed, for example some comet as it approaches earth, and after a while when it returns after a few years depending on its cycle, we can try returning to earth, provided if we survive the landing on the comet, then we will surely be able to prove Einstein's prediction. :|
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Re: Physics Thread.

Post by Amber G. »

The speed of earth around the sun is around 2/3rds the speed of light. We are already travelling so fast...
Speed of earth around the sun (wrt to sun) is about 30 km/sec. I can be called 'fast' but still it is not around 2/3 but about 1/10,000 the speed of light. :!:
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Re: Physics Thread.

Post by sanjeevpunj »

^^^ I calculated wrongly.
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Re: Physics Thread.

Post by Neshant »

if we can figure out how to cryogenically freeze a person without killing him or damaging him, so called time travel might work. put him in the freezer right next to the french fries. Dethaw him 1000 years into the future.

kind of like the frozen embryo used for test tube babies.
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Re: Physics Thread.

Post by SaiK »

for that, we need a genetically modified hibernating human beings. [polar bears can be a basic study model]
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Re: Physics Thread.

Post by brihaspati »

What about spinning large masses? Time should slow down isnt it? And you could go back or forth depending on which direction you choose to loop compared to the rotational axis.
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Re: Physics Thread.

Post by SaiK »

well, a thought process is all that is needed to contract or expand time. It is relative anyways..
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Re: Physics Thread.

Post by gakakkad »

Amber G. wrote: The book is available here online:
http://www.archive.org/stream/physicsfo ... 7/mode/2up
:) (What is 100 times the amount you bought it for ? :) )



Many such books seem to be available at amazon.
Also, as long as it is strictly for personal use, here is a pdf copy
Hope it is helpful.
Thanks . Nostalgia feeling. Catching up on my physics these days in free time.
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Re: Physics Thread.

Post by negi »

Neshant wrote:if we can figure out how to cryogenically freeze a person without killing him or damaging him, so called time travel might work. put him in the freezer right next to the french fries. Dethaw him 1000 years into the future.

kind of like the frozen embryo used for test tube babies.
Boss looks like you just watched 'Demolition man' . :mrgreen:
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Re: Physics Thread.

Post by sanjeevpunj »

Freezing and preserving for hundreds of years, and then thawing and reviving normal biological systems, is concept that has been used in many SCI-Fi Stories, and theoretically too, suspension of biological processes is a possibility. It has to be proved that it works, though. None of the frozen russians soldiers during WWII recovered, nor did the mammoths found in Siberia.The soul just leaves the frozen body, IMO and searches for rebirth.
Anyone willing to be frozen, as an experimental subject? We could try one day freeze for a start. :lol:
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Re: Physics Thread.

Post by Bade »

Concept of soul is a myth, a creation of the brain. There is no proof of its existence. It is an idea being pushed by Yindoo fundamentalists. :lol:
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Re: Physics Thread.

Post by gakakkad »

sanjeevpunj wrote:Freezing and preserving for hundreds of years, and then thawing and reviving normal biological systems, is concept that has been used in many SCI-Fi Stories, and theoretically too, suspension of biological processes is a possibility. It has to be proved that it works, though. None of the frozen russians soldiers during WWII recovered, nor did the mammoths found in Siberia.The soul just leaves the frozen body, IMO and searches for rebirth.
Anyone willing to be frozen, as an experimental subject? We could try one day freeze for a start. :lol:

Actually it is even done in real life. Not exactly freezing but Induced hypothermia .

http://en.wikipedia.org/wiki/Therapeutic_hypothermia

If you are living near ny u might be able to see some research @ columbia university.
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Re: Physics Thread.

Post by sanjeevpunj »

Wow, interesting. Bookmarked the page for further reading, thanks Gakakkad ji.
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Re: Physics Thread.

Post by Amber G. »

Some time ago, here (and also in nuke dhaga) we discussed about U/Th in the core of the earth, and GuruPrabhu post about neutrino's etc...

I gave the link to the article in Nature but it is not accessible to general public).

Here is quite a nice popular article from recent Physics Today..

gakakkad et al - enjoy..

>>>Neutrinos from Earth’s interior measure the planet’s radiogenic heating
http://dx.doi.org/10.1063/PT.3.1240
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Re: Physics Thread.

Post by Neshant »

Physicist discusses his experiment for Time Travel



Aside from the fact that the guy suffered a lot of hardship when he was young, he managed to become a physicist. His experiments are about time travel. I don't know enough about quantum physics but it sure sounds interesting.

He's written a book - Time Traveller and his name is Dr. Ronald Mallet.

This kind of research is really far out but if his expeirment does succeed, it really would be revolutionary.
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Hindu Paradigms as Foundation for New Directions in the Scie

Post by parsuram »

Following is the introduction to an essay I have written recently. It provides the framework on which I have successfully built about 20-25 years of serious experimental research, and on which I have also built up an alternate understanding of physical and biological phenomenon. I will be interested in begining a serious dialog with physicysts who are atleast as dedicated to their Hindu faith & philosophy as they are to physics (and I hope, are more adept & better at both than I am).
The Human species, by instinct, ceaselessly embarks upon journeys of learning through its senses and its mind. Yet, in all these journeys, it remains always at the center of an infinite sphere of knowledge; no matter in which direction it travels, it acquires information & learning; and its next step is rationally predicated upon all the steps it has already taken. Thus it is that so much depends on the initial direction of these journeys of the human mind – since much of how groups of humans who travel together on such journeys organize their lives and their societies on their collective understanding of the universe beyond themselves.

Now, it came to pass in human antiquity, that there were groups of peoples who embarked on intellectual journeys in different places, asking more or less the same questions. And remarkably, some of them came to diametrically opposing answers or conclusions than others. In essence, they disagreed on the reality of subjective experience. One view, now dominant among all most all peoples, comes to us from the rationalist Greeks. This view asserts that reality is based on a shared experience; that truth is what the vast majority of people share as a common experience. Thus, a man who sees a yellow sky and white tree leaves is not experiencing any truth, because as is generally experienced, the sky is blue and the leaves are green. The individual with the alternate experience is missing the truth. This is Truth by consensus; democratic truth. This, along with Judeo-Christian theology with its monotheistic divinity as an entity external to and creator of the universe have become the dominant paradigm governing the vast majority of advanced organized human societies of our time. The Bible is the bedrock which has provided direction to the Western Paradigm. In essence, the intellectual foundation of western civilization rests in Genesis, the first book of the Bible, which states categorically that god created man in his own image, and bestowed upon man “dominion over the beasts on the land, birds of the air, and all creatures of the deep”. There is more, relating to the complicated divinity of Jesus Christ, and it all comes together neatly to give us, not just Western Theology but also the impetus that has taken Man to the moon, biotechnology to fight the natural processes of physiological decay, and all the flowers and fragrance which are the art, literature, science, mathematics, industry, jurisprudence and more that is the best of Western Civilization. In its entirety, Western civilization represents Man’s “outward journey”, and, as constituted, its underlying Western civilizational paradigms continue to expand into all alternative human enterprises, having begun to do so with increasing rapidity about 1500 years ago.

We Hindus have been, and stubbornly continue to be, the exception. We are the original fountain from which flow Indic traditions, viz, Jain, Buddhist and Sikh theologies & philosophies. Despite almost a thousand years of subjugation, we represent the alternative; indeed, we are all the alternatives, inclusive also of various paradigms based on shared objective realities alone. The alternative to one God, is 0, 2, 3, 4, etcetera infinity of Gods; the alternative to an external single God creator, is a Deity that itself constitutes the universe and animates it; the alternative to a defined singular event of Universe creation from which issues a single, one dimensional time line, is cyclical acts of Universe creation and destruction intimately associated with a Deity/Deities. That is us, the polytheistic Hindus and our other Indic faiths. We are those who accept the reality of subjective experience, and inculcate it, study & revel in it through yog and other disciplines. We assert that subjective truth is as much a part of the greater universal truth as is objective truth. It is given to us, therefore, to maintain and uphold this alternate paradigm that governs our enquiry into the universe. In essence, Hinduism and its variant Indic intellectual pursuits represent Mankind’s “Inward Journeys”, which, we assert, equally or better describe the ultimate reality and truth concerning the universe external to ourselves. Thus it is that just as Western canons shaped and continues to shape western society, so do Hindu paradigms govern Hindu and associated Indic faith & societies.
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Re: Physics Thread.

Post by Amber G. »

Worth mentioning: Attended a very interesting colloquium about "Topological insulators to Majorana Fermions" from Charlie Kane
( University of Pennsylvania). Unlike most, this was interesting to even non-specialists.. quite possible that topological insulators (and super conductors) are next big stuff in condensed matter physics.

Some intro from his lecture (slightly edited to make it readable for this audience)
>>>

A topological insulator is a material that is an insulator on its interior, but has special conducting states on its surface. These surface states are unlike any other known two dimensional conductor. They are characterized by a unique Dirac type dispersion relation and are protected by a topological property of the material's underlying electronic band structure. Topological insulators have attracted considerable interest as a fundamentally new electronic phase with applications from spintronics to quantum computing. In this talk we will outline the theoretical discovery of this phase and describe experiments that have observed its signatures in both two and three dimensional electronic systems. We will close by arguing that the proximity effect between an ordinary superconductor and a topological insulator leads to a novel interface state that may provide a new venue for observing the elusive Majorana fermion and for realizing proposals for topological quantum computation.

You can see some cool stuff (and very understandable lectures) on this guys web
http://www.physics.upenn.edu/~kane/

****
Majorana was, of course, one of the most brilliant physicist who died (or went missing) quite young in very mysterious (No one knows what happened, he just disappeared ) way. Fermi, Heisenberg considered him one of the most brilliant person they met.
(BTW, George Sudershan got Majorana prize in 2006)
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Re: Hindu Paradigms as Foundation for New Directions in the

Post by Rudradev »

parsuram wrote:Following is the introduction to an essay I have written recently. It provides the framework on which I have successfully built about 20-25 years of serious experimental research, and on which I have also built up an alternate understanding of physical and biological phenomenon. I will be interested in begining a serious dialog with physicysts who are atleast as dedicated to their Hindu faith & philosophy as they are to physics (and I hope, are more adept & better at both than I am).
The Human species, by instinct, ceaselessly embarks upon journeys of learning through its senses and its mind. Yet, in all these journeys, it remains always at the center of an infinite sphere of knowledge; no matter in which direction it travels, it acquires information & learning; and its next step is rationally predicated upon all the steps it has already taken. Thus it is that so much depends on the initial direction of these journeys of the human mind – since much of how groups of humans who travel together on such journeys organize their lives and their societies on their collective understanding of the universe beyond themselves.

Now, it came to pass in human antiquity, that there were groups of peoples who embarked on intellectual journeys in different places, asking more or less the same questions. And remarkably, some of them came to diametrically opposing answers or conclusions than others. In essence, they disagreed on the reality of subjective experience. One view, now dominant among all most all peoples, comes to us from the rationalist Greeks. This view asserts that reality is based on a shared experience; that truth is what the vast majority of people share as a common experience. Thus, a man who sees a yellow sky and white tree leaves is not experiencing any truth, because as is generally experienced, the sky is blue and the leaves are green. The individual with the alternate experience is missing the truth. This is Truth by consensus; democratic truth. This, along with Judeo-Christian theology with its monotheistic divinity as an entity external to and creator of the universe have become the dominant paradigm governing the vast majority of advanced organized human societies of our time. The Bible is the bedrock which has provided direction to the Western Paradigm. In essence, the intellectual foundation of western civilization rests in Genesis, the first book of the Bible, which states categorically that god created man in his own image, and bestowed upon man “dominion over the beasts on the land, birds of the air, and all creatures of the deep”. There is more, relating to the complicated divinity of Jesus Christ, and it all comes together neatly to give us, not just Western Theology but also the impetus that has taken Man to the moon, biotechnology to fight the natural processes of physiological decay, and all the flowers and fragrance which are the art, literature, science, mathematics, industry, jurisprudence and more that is the best of Western Civilization. In its entirety, Western civilization represents Man’s “outward journey”, and, as constituted, its underlying Western civilizational paradigms continue to expand into all alternative human enterprises, having begun to do so with increasing rapidity about 1500 years ago.

We Hindus have been, and stubbornly continue to be, the exception. We are the original fountain from which flow Indic traditions, viz, Jain, Buddhist and Sikh theologies & philosophies. Despite almost a thousand years of subjugation, we represent the alternative; indeed, we are all the alternatives, inclusive also of various paradigms based on shared objective realities alone. The alternative to one God, is 0, 2, 3, 4, etcetera infinity of Gods; the alternative to an external single God creator, is a Deity that itself constitutes the universe and animates it; the alternative to a defined singular event of Universe creation from which issues a single, one dimensional time line, is cyclical acts of Universe creation and destruction intimately associated with a Deity/Deities. That is us, the polytheistic Hindus and our other Indic faiths. We are those who accept the reality of subjective experience, and inculcate it, study & revel in it through yog and other disciplines. We assert that subjective truth is as much a part of the greater universal truth as is objective truth. It is given to us, therefore, to maintain and uphold this alternate paradigm that governs our enquiry into the universe. In essence, Hinduism and its variant Indic intellectual pursuits represent Mankind’s “Inward Journeys”, which, we assert, equally or better describe the ultimate reality and truth concerning the universe external to ourselves. Thus it is that just as Western canons shaped and continues to shape western society, so do Hindu paradigms govern Hindu and associated Indic faith & societies.
Parsuram,

Fascinating writeup. Would love to read the entire essay, if available, and consider your conclusions.

Can't really disagree with anything you've stated here in the dichotomy between Western Judeo-Christian philosophical discipline and Indic thought which encompasses the entire antithesis of the former. Just one nitpick, perhaps. You say:
There is more, relating to the complicated divinity of Jesus Christ, and it all comes together neatly to give us, not just Western Theology but also the impetus that has taken Man to the moon, biotechnology to fight the natural processes of physiological decay, and all the flowers and fragrance which are the art, literature, science, mathematics, industry, jurisprudence and more that is the best of Western Civilization.
I wonder if this isn't perhaps giving too much credit to Judeo-Christianity. As I see it, it wasn't that neat at all. You are absolutely correct in attributing the initial impetus of inquiry to the rationalist Greeks, leading to a manner of thinking about the universe that found its greatest realization in Hellenistic Rome. However, with the onset of Christianity came the Dark Ages, setting back the course of intellectual development in the West by several centuries.

To the extent that the Renaissance represented a recovery from this period of stagnation, it was still a cloistered and apologetic recovery. It created wonderful art, most of which paid ample thematic homage to the god of the Bible even as it rediscovered Hellenistic Greco-Roman form and technique. In the sciences, Renaissance-era scholars largely shielded themselves from any course of intellectual inquiry that might invoke the ire of the mighty Church (Galileo, an exception, discovered this to his peril when his eyes were put out for suggesting that the planets go around the sun.)

It was only after the Thirty Years' War (claiming 20% of the entire population of Europe!) finally hammered home the terrible consequences of overpowered and Jihadistic Church rule, that relatively "secular" power structures began to evolve and reshape the European sociopolitical landscape in a manner that was relatively independent of the Catholic and various Protestant Churches.

Only then, did the Age of Enlightenment finally dawn in the West. In delving back into the Greek Rationalist/Roman Hellenist roots of Western thought (before Christianity descended on them like a mosaic viruses) the West was able to rediscover what it had left behind. It is to the Enlightenment and its pre-Christian antecedents, then, that I would credit:
the impetus that has taken Man to the moon, biotechnology to fight the natural processes of physiological decay, and all the flowers and fragrance which are the art, literature, science, mathematics, industry, jurisprudence and more that is the best of Western Civilization.
One thing I will say for the Church though... in the Middle Ages, by fostering a Europe consumed with bloody religious warfare, it spurred the development of military technique (in terms of shipbuilding, gun design, steelworking and other things) that created weapons more advanced than anything possessed by the rest of mankind. Also, in the Early Modern Age, Christianity provided Europeans with the kind of single-minded fanaticism and extreme moral hypocrisy required to invade the lands of others, exterminate the weaker inhabitants and steal their wealth on a colossal scale. Without successful Colonialism, many experimental endeavours of the Age of Enlightenment may have remained underfunded, and many of its technological marvels may never have been realized. This may never have happened in a "Dharmic" setting.

Some of my own thoughts about this kind of thing are on my blog, if you're interested

http://indospheric.blogspot.com

Which I haven't updated in far too long.
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Re: Physics Thread.

Post by rsingh »

It is raining in Brusselbad these days. Yesterday I saw double rainbow. sky was clouded. Sky under the first rainbow was lighter in colour. It was darkest in between two arcs. Why ? I took pics with my phone but too lazy to upload. May be some otherday.
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Re: Physics Thread.

Post by anishns »



A very practical invention for the masses using simple physics
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Re: Physics Thread.

Post by parsuram »

Rudra Guru:

Would gladly send you a copy to any email you provide.
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