Physics Discussion Thread

Manishw · Post by **Manishw** » 14 Aug 2010 10:29

First of all I must congratulate everybody here on collecting nuggets from various sources.Consider me as a newbie as far as finding my way around here. I am currently trying to wrap my mind on the below mentioned hypothesis, so kindly indulge me and if already posted pls point it out to me so that I can make necessary corrections.

THUNDERBOLTS OF THE GODS

http://www.google.co.in/url?sa=t&source ... 3jpcBlhECg

http://www.google.co.in/url?q=http://vi ... dY0WZPZkDA

Comments and suggestions would be appreciated.

On another note I would also like to quote Modern 'Seers' like UGK, Rajneesh, Gopi Krishna, Jiddu etc to square off certain points in physics.Hope its not a no-no here.If it is would be glad if pointed out to me so that I abstain.

Will wait for a couple of days before posting further in case of no replies.

Amber G. · Post by **Amber G.** » 15 Aug 2010 07:43

x - post:
Paper at: http://pubs.acs.org/doi/abs/10.1021/ac1 ... ode=ancham
Another nice news, from MIT (and 2 IIT' guys!) and using invention by CV Raman:

(Should hit Indian News papers)
Shining a light — literally — on diabetes
Device from MIT lab could help diabetic patients monitor their blood glucose levels without finger pricks

People with type 1 diabetes must keep a careful eye on their blood glucose levels: Too much sugar can damage organs, while too little deprives the body of necessary fuel. Most patients must prick their fingers several times a day to draw blood for testing.

To minimize that pain and inconvenience, researchers at MIT’s Spectroscopy Laboratory are working on a noninvasive way to measure blood glucose levels using light.

First envisioned by Michael Feld, the late MIT professor of physics and former director of the Spectroscopy Laboratory, the technique uses Raman spectroscopy, a method that identifies chemical compounds based on the frequency of vibrations of the bonds holding the molecule together. The technique can reveal glucose levels by simply scanning a patient’s arm or finger with near-infrared light, eliminating the need to draw blood.

Spectroscopy Lab graduate students Ishan Barman {trained at IIT Kharagpur} and Chae-Ryon Kong are developing a small Raman spectroscopy machine, about the size of a laptop computer, that could be used in a doctor’s office or a patient’s home. Such a device could one day help some of the nearly 1 million people in the United States, and millions more around the world, who suffer from type 1 diabetes.

Researchers in the Spectroscopy Lab have been developing this technology for about 15 years. One of the major obstacles they have faced is that near-infrared light penetrates only about half a millimeter below the skin, so it measures the amount of glucose in the fluid that bathes skin cells (known as interstitial fluid), not the amount in the blood. To overcome this, the team came up with an algorithm that relates the two concentrations, allowing them to predict blood glucose levels from the glucose concentration in interstitial fluid.

However, this calibration becomes more difficult immediately after the patient eats or drinks something sugary, because blood glucose soars rapidly, while it takes five to 10 minutes to see a corresponding surge in the interstitial fluid glucose levels. Therefore, interstitial fluid measurements do not give an accurate picture of what’s happening in the bloodstream.

To address that lag time, Barman and Kong developed a new calibration method, called Dynamic Concentration Correction (DCC), which incorporates the rate at which glucose diffuses from the blood into the interstitial fluid. In a study of 10 healthy volunteers, the researchers used DCC-calibrated Raman spectroscopy to significantly boost the accuracy of blood glucose measurements — an average improvement of 15 percent, and up to 30 percent in some subjects.

The researchers described the new calibration method and results in the July 15 issue of the journal Analytical Chemistry. In addition to Feld, Barman and Kong, authors include Ramachandra Rao Dasari { build lasers at IIT/K} , associate director of the Spectroscopy Lab, and former postdoctoral associate Gajendra Pratap Singh.

Michael Morris, professor of chemistry at the University of Michigan, says the group appears to have solved a problem that has long stymied researchers. “Getting optical glucose measurements of any sort is something people have been trying to do since the 1980s,” says Morris, who was not involved in this study. “Usually people report that they can get good measurements one day, but not the next, or that it only works for a few people. They can’t develop a universal calibration system.”

<snip>

In October, Barman will receive the Tomas A. Hirschfeld Award at the Federation of Analytical Chemistry and Spectroscopy Societies Conference, for his work on improving spectroscopy-based glucose measurements.

Another interesting tid-bit (wonder any one else will report that): that: Dr. Ramachandra Rao Dasari got M.Sc. from Benares Hindu University and Ph.D. from Aligarh Muslim University and taught (when I was at IIT/K) at IIT Kanpur. ..at IIT/K he built one of the largest laser labs ..many lasers, used for some Indian Industries etc, were actually built at IIT Kanpur .. he worked with companies like BHEL for their laser technology/instrumentation. ..

Congrats to these guys. This will really help common people.

Bade · Post by **Bade** » 16 Aug 2010 22:39

Looks like a new site for the INO (Indian Neutrino Observatory) has been selected. An updated image of the site is below.
The new INO site at Bodi Hills,TN

Amber G. · Post by **Amber G.** » 17 Aug 2010 09:35

xpost:

abhishek_sharma wrote:E.C.G. Sudarshan shares Dirac Medal with Italian

http://www.hindu.com/2010/08/14/stories ... 032400.htm

Congrats to ECG Sudarshan..
Also from Above:

Both Professor Cabibbo and Professor Sudarshan were passed over by the Nobel committee earlier. The Italian physicist in 2008 and Professor Sudarshan in 1979 and 2005.

Prof Cabibbo the co-winner died today!

Sanjay M · Post by **Sanjay M** » 27 Aug 2010 07:51

Here's something profoundly earth-shaking:

Thursday, August 26, 2010
Fine Structure Constant Varies With Direction in Space, Says New Data
A spatial variation in the fine structure constant has profound implications for cosmology

ramana · Post by **ramana** » 10 Sep 2010 03:14

God did not create the universe, says Hawking

By Michael Holden

Sep 3, 2010

LONDON (Reuters) – God did not create the universe and the "Big Bang" was an inevitable consequence of the laws of physics, the eminent British theoretical physicist Stephen Hawking argues in a new book.

In "The Grand Design," co-authored with U.S. physicist LeonardMlodinow, Hawking says a new series of theories made a creator of the universe redundant, according to the Times newspaper which published extracts on Thursday.

"Because there is a law such as gravity, the universe can and will create itself from nothing. Spontaneous creation is the reason there is something rather than nothing, why the universe exists, why we exist," Hawking writes.

Full report at:

LINK

RamaY · Post by **RamaY** » 10 Sep 2010 03:29

^

God doesn't create anything outside himself. If that is true, as the Abrahamic religions preach, then God's omnipresence will fail and he stops becoming god.

Param became the viswam (universe). When viswam dissolves, Param will remain; like gold transforming into jewelry and remaining as gold when jewelry is destroyed/dissolved.

This image always reminds me of Siva Linga. I don't think universe will "have to" be horizontal.

Bade · Post by **Bade** » 10 Sep 2010 04:42

^^^ I don't think the image above is supposed to represent what the universe looks like geometrically. The shape is a function of a map projection. So there is nothing special about this apparently ellipsoidal look or feel.

Amber G. · Post by **Amber G.** » 17 Sep 2010 11:38

Indian scientists’ contribution to LHC significant

Contribution of Indian scientists in building the ‘Large Hadron Collider (LHC)’, the world’s biggest particle accelerator near Geneva to simulate the ‘big-bang’ that caused the universe, has been “proportionately more” than even American scientists.

The 100-strong team of scientists from India who participated in building the LHC at the ‘European Organisation for Nuclear Research (CERN)’, was much less than the American Scientists contingent, but the “contribution of Indians has been proportionately much larger”, the LHC’s Project Leader, Dr Lyndon Evans said here in his first-ever visit to India.

<snip>
The Indian group was particularly strong in heavy ion physics, he added to cheers from the large audience. With huge amount of money invested in the LHC in which over 3,000 scientists from 39 countries were working, “the CERN is really the United Nations of Science”, Dr Evans said. The CERN was started in 1954 with a view to bringing Europe together again after World War-II.
<snip>

.

Sanjay M · Post by **Sanjay M** » 21 Sep 2010 09:37

Something here worth looking at - UltraDense Deuterium:

http://dx.doi.org/10.1088/1742-6596/244/3/032036
George H Miley, Xiaoling Yang, Hora Heinrich, Kirk Flippo, Sandrine Gaillard, Dustin Offermann and D Cort Gautier (2010). "Advances in proposed D-Cluster inertial confiment fusion target". Journal of Physics: Conference Series 244 032036. doi:10.1088/1742-6596/244/3/032036

http://iopscience.iop.org/1742-6596/244 ... 032036.pdf

Abstract
Our recent research has developed a technique for imbedding ultra high density deuterium "clusters" (D cluster) in Palladium (Pd) thin film. Experiments have shown that in Pd these condensed matter state clusters approach metallic conditions, exhibiting super conducting properties. This deuterium cluster is achieved through electrochemically loading-unloading deuterium into a thin metal film, such as Palladium (Pd). During the loading process, Palladium lattice expands significantly due to invasion of deuterium into the interstitial sites. With the large enough stress, some linear lattice imperfections, called dislocations, form at / transformation interface. These dislocation defects form a strong potential trap causing deuterium to condense. In the present study, a new method employing nano-structuring of the Pd is proposed to significantly improve the site density over the target volume, suggesting that a sizable region of the compressed target deuterium can reach densities an order of magnitude higher than possible with prior target designs. This improved cluster packing fraction will enable a significant increase of the fusion reaction burn density, hence the target burn-up efficiency.

Amber G. · Post by **Amber G.** » 23 Sep 2010 09:28

CU Physicist Carl Wieman appointed to White House science and technology policy adviser

A Nobel laureate from the University of Colorado at Boulder was confirmed by the U.S. Senate last week to serve as a science and technology policy adviser to the White House.
Carl Wieman "is expected to spearhead the administration's push to improve science education, drawing upon his pioneering work at the University of Colorado, Boulder, to strengthen the undergraduate training of science and math teachers," the American Association for the Advancement of Science reported on its website.
Wieman shared the Nobel Prize in physics in 2001 for creating Bose-Einstein condensate, a gaseous form of matter produced at absolute zero and helpful to the understanding of quantum physics.
He will be on leave from CU and the University of British Columbia while working in his federal government position.

Manishw · Post by **Manishw** » 07 Oct 2010 21:46

http://www.ens-newswire.com/ens/oct2010 ... 04-01.html

WASHINGTON, DC, October 4, 2010 (ENS) - A team of U.S. planet hunters has discovered an Earth-sized body orbiting a nearby star in the middle of the star's habitable zone, where liquid water could exist on the planet's surface and the planet could sustain life as we know it.

The planet, named Gliese 581g, is about three to four times the mass of Earth. The scientists say this mass indicates a rocky planet with a definite surface and enough gravity to hold onto an atmosphere.

Amber G. · Post by **Amber G.** » 08 Oct 2010 02:55

(All over the news)

Andre Geim and Konstantin Novoselov won Nobel Prize for graphene!

(Some in Russia are not happy with it (they say wrong people are getting credit)

My son knew Andre Geim (He gave some lectures/seminars for American young scientists) and says the guy is a very good and amusing teacher.

Bade · Post by **Bade** » 08 Oct 2010 08:41

We had invited Carl Weiman just before he won the Nobel for a colloquium, and what a humble guy. Never seen an accomplished physicist with such humility. He is an excellent choice for the job. He had some new ideas on science education way back that I recall him talking about quite animatedly.

Amber G. · Post by **Amber G.** » 24 Oct 2010 07:29

This could probably also go in nukkad thread, but I recently read "Copenhagen" (Play by Michael Fray) and liked it very much. It is based around the famous meeting in Copenhagen in 1941, between the physicists Niels Bohr and Werner Heisenberg. Though play is old, it was the first time I read it. Highly recommend it (its less than 100 pages).

Mort Walker · Post by **Mort Walker** » 24 Oct 2010 09:40

^^^Although I've heard the play is very good, I haven't had a chance to read it yet. However, I don't think people should vilify Heisenberg of 1941. He may have deliberately overestimated the amount of Uranium needed for an uncontrolled chain reaction necessary for a fission bomb because he didn't want it in the Nazis hands. He did in fact dissuade Albert Speer, the German Armament minister, in 1942 about an atomic bomb not being practical. Around 1948 at the University of Göttingen, one of Heisenberg's neighbor was a visiting Indian professor with whom he met often that academic year. The Indian professor, whom I would not like to mention as it may give away my identity, recalled to me the discussions he had with Heisenberg about India and Germany. The irony of the situation was not lost on Heisenberg, where India had won its freedom from Britain without resorting to war based on the power of ideas; and Germany, defeated in war, now lost its freedom to be an occupied country by the Americans, Russians and British.

Amber G. · Post by **Amber G.** » 24 Oct 2010 21:13

^^^ I think you will like it, specially if you know the historical background, it discusses Albert Speer / overestimation of critical mass of U etc.. (actually in the play mentions little known taped conversation between Heisenberg and Hahn which give credence that he actually knew the right calculation and knowingly gave high figures)

The play writer has done a lot of research and talked to lot of people to get many interesting facts and stories in the play.

I have heard Heisenberg when he was in USA (early 70's). Also I heard lot of first hand interesting stories from my professors (and other friends/family) who spent time in Bohr's institute or otherwise knew the crowd personally...

(Seems that anyone who was doing serious research in Physics in that time spent some time in Bohr's place)

BTW, Heisenberg visited India (30's), gave lectures in QM there, was a guest of Ravindranath Tagore, went to Darjeeling and did some serious mountain climbing in Himalayas...etc...

Mort Walker · Post by **Mort Walker** » 24 Oct 2010 22:56

^^^It was recently shown in my local area followed by a discussion with physicists, historians and philosophers, but I didn't have time and missed it. In fact, Heisenberg's son is a professor of Physics at Univ. of NH and has commented on this play, its worth reading his comments as well. At the time, physicists in Europe associated with Bohr and in the US they hung around Oppenheimer. Including my personal hero - Robert Serber. I didn't know that Heisenberg visited India in the 1930s.

Its great you got the chance to attend a colloquium with Heisenberg.

rsingh · Post by **rsingh** » 26 Oct 2010 00:50

BTW one pooch for Gurus. Is it possible to divert a storm from populated areas using bombs. When bomb explodes it creates vacuum..............thus low pressure/high pressure differential. Who has the most powerful non-radiation bomb.

Amber G. · Post by **Amber G.** » 29 Oct 2010 22:35

^^^ One trouble, to put in perspective, a strong to medium storm release energy up to 10^19 joules per hour in terms of wind energy etc..(This is equivalent of, say about 100,000 (or more) Hiroshima nuclear bombs)

(Dry ice, or bombs etc.. problem is to produce any significant effect, even if selectively used, even a large bomb is not likely be effective)

rsingh · Post by **rsingh** » 30 Oct 2010 01:47

^^^ We do not need energy to counter the storm. Bombs can be used to change the path ie
- create vacuum in air-uptake area which can stop or change the direction of wind for seconds which will eventually affect general direction. JMT

Amber G. · Post by **Amber G.** » 30 Oct 2010 06:05

No one is talking about "countering"..it was just to give a perspective....if I blow at a candle, I can blow it out (not by countering anything but just deny some oxygen)... but blowing might not work in a forest fire (if your blowing reduces the oxygen by 0.000001% only) ..Beauty of physics is that it is relatively not hard to do calculation.. how big vacuum can you reasonably expect from your bomb etc and you may do it yourself before going further.

Point is simple calculation may help....

wig · Post by **wig** » 04 Nov 2010 18:51

http://www.telegraph.co.uk/news/newstop ... cloak.html

new material that could be used to create a real-life Harry Potter-style "invisibility cloak" has been designed by British scientists.
The material, called "Metaflex" may in future provide a way of manufacturing fabrics that manipulate light.

Metamaterials have already been developed that bend and channel light to render objects invisible at longer wavelengths
Describing their work in the New Journal of Physics, the researchers write: "Arguably, one of the most exciting applications of Metaflex is to fabricate three-dimensional flexible MMs (metamaterials) in the optical range, which can be achieved by stacking several Metaflex membranes on top of one another...

"These results confirm that it is possible to realise MMs on flexible substrates and operating in the visible regime, which we believe are ideal building blocks for future generations of three-dimensional flexible MMs at optical wavelengths

Murugan · Post by **Murugan** » 18 Nov 2010 22:01

breaking news

‘Anti-matter’ trapped in physics breakthrough

http://www.ft.com/cms/s/0/abe03bae-f314 ... z15eIa00Lu

rsingh · Post by **rsingh** » 25 Nov 2010 20:14

When light takes 3 billion years to reach to us it means source is an event that occurred some where in space 3 billion years ago. In fact it is light from past and we are observing past events only. Going on this do we have a particular direction in space from where light from big bang is suppose to come?

Pratyush · Post by **Pratyush** » 10 Dec 2010 10:38

This belongs here

Diamond-studded planet discovered!

GuruPrabhu · Post by **GuruPrabhu** » 27 Dec 2010 10:18

rsingh wrote:When light takes 3 billion years to reach to us it means source is an event that occurred some where in space 3 billion years ago. In fact it is light from past and we are observing past events only. Going on this do we have a particular direction in space from where light from big bang is suppose to come?

Yes, all big bang comes from direction of Islamabad. But this theorem is limited to light since 7th century AD. Billion year stuff is not Halaal.

rsingh · Post by **rsingh** » 27 Dec 2010 22:06

GuruPrabhu wrote:
rsingh wrote:When light takes 3 billion years to reach to us it means source is an event that occurred some where in space 3 billion years ago. In fact it is light from past and we are observing past events only. Going on this do we have a particular direction in space from where light from big bang is suppose to come?
Yes, all big bang comes from direction of Islamabad. But this theorem is limited to light since 7th century AD. Billion year stuff is not Halaal.

Guys please stick to the topic. If you do not have answer then no need to post. I have some questions because I think. If these are too easy for you guys please do not laugh. Answer it. If you do not have answer the wait for somebody to enlighten us. Thats it.

Bade · Post by **Bade** » 27 Dec 2010 22:35

rsingh, the way to look at the big bang is not as an event that happened in space-time some N billion years ago, but as 'the event' which created the very space-time we live in along with the stars, planets and other interstellar material. So as space-time inflated since the initial seed event, and the light (the full EM spectrum) from those times permeate through this expanding space-time with no special preference for directionality. So wherever you look you should see the signature of this big-bang event. That is the simplistic view. People have been looking for anisotropies of this relic and found interesting results which simply cannot be summarized in a few words.
You can begin somewhere like http://map.gsfc.nasa.gov/ and follow to earlier efforts like the COBE satellite data and a few others.

Bade · Post by **Bade** » 27 Dec 2010 22:47

Where are those global warming pundits? It is coldest winter in Yeerope for last 135 years. I have to dig my way out of my domus everyday

From the whine thread, but some fizziks involved here in understanding why this is so. More the global warming, more your asses are going to freeze in Oirope.

More warmer the waters are in the equatorial atlantic, more the moisture that is carted off towards the northern latitudes and as it meets it 72 houris on a reindeer driven artic jet stream bringing in the chill, it all freezes as beautiful snow over old Neanderthal land. Simple onlee, no ? No global warming then less moisture to transport and all ij well in paradise of a land that is Europe.

rsingh · Post by **rsingh** » 27 Dec 2010 22:49

Bade wrote:rsingh, the way to look at the big bang is not as an event that happened in space-time some N billion years ago, but as 'the event' which created the very space-time we live in along with the stars, planets and other interstellar material. So as space-time inflated since the initial seed event, and the light (the full EM spectrum) from those times permeate through this expanding space-time with no special preference for directionality. So wherever you look you should see the signature of this big-bang event. That is the simplistic view. People have been looking for anisotropies of this relic and found interesting results which simply cannot be summarized in a few words.
You can begin somewhere like http://map.gsfc.nasa.gov/ and follow to earlier efforts like the COBE satellite data and a few others.

Thanks for explanation Bade mian. It will take some time for me to understand this.

GuruPrabhu · Post by **GuruPrabhu** » 30 Dec 2010 03:40

Bade saar,

thank you for the explanation. My questions -- did "time" exist before the big bang? (my guess is not). did "energy" exist before big bang. (my guess is yes). finally, did "matter" exist before big bang (my guess is no).

Bade · Post by **Bade** » 01 Jan 2011 05:33

Even though this is a physics thread, we can speculate within certain limits. Some things are hard to prove beyond a certain point as facts. As for question on "time", it is widely accepted that space-time curvature is determined by presence of massive objects, so one can argue that mass and space-time are equivalent. Now mass and energy are also same-to-same by virtue of E=mc^2. So presence of energy, mass implies existence of space-time curvature.

In the sense that space & time are connected intimately in the context of Special Relativity and General Relativity theories, it may be less meaningful to ask if "time" alone existed before the big-bang, if big-bang is what created space-time in the first place.

This ignores, other prevailing concepts of multiple universes and many other cutting-edge speculative works without any experimental/observational evidence but can be constructed by talented mathematical "conductors"

of physics with a fine theoretical bent of mind.

But as of now we have observational evidence from our Universe only, pointing to a big-bang. What happened before is a matter of speculation and the loud talented ones vying for tenured positions to practice their art further.

Anyway, it hard to argue for "energy" to exists before the big-bang without invoking multi-verse ideas or branes collapsing with each other leading to big-bang at the point of contact.

Pure speculation again all of it, but interesting to explore if you are mathematically gifted. I am not !

GuruPrabhu · Post by **GuruPrabhu** » 03 Jan 2011 08:25

Bade Saar,

If energy did not exist before the big bang then where did the energy come from? Does it not violate energy conservation, hain ji?

Bade · Post by **Bade** » 03 Jan 2011 09:47

Singularities cannot be very well understood even with existing mathematical constructs from what little I understand and seem to remember. Even practicing fizzicists will also concur I hope, if they visit the thread.

Having said that what does it mean to say " energy from before the big bang" ? In one set of theories which uses inflation (Alan Guth version) which is fashionable you do no get to ask about before the BB event. The way to understand it is that inflation happened some time after the BB. The delta of time is very infinitesimally small as in some zillionth of a fraction of a sec (without referring to actual nos), and you conveniently do not have to explain anything before that

Also, think about it if time or more exactly space-time can be infinitesimally small even smaller than when inflation took over, the energy density is also approaching infinity, no ? So hand-wavingly I can claim all energy came from this infinity or infinite density...so no violation of any conservation, hain ?

Why do you think Wall St is ruled by Fizzicists who did not get tenure

we are trained to push large sums under the carpet and renormalize things like a bank bailout onree.

GuruPrabhu · Post by **GuruPrabhu** » 03 Jan 2011 11:03

thank you for the honesty, Bade Saar. It ij a hocus-phocus dhagaa now, phyjjyx ij eggspojed.

Bade · Post by **Bade** » 03 Jan 2011 11:13

Not so fast Guru-ji, cause this hocus-pocus has mathematics to back it up, unlike all the other types deemed as spirituality or various flavors of belief systems. More honest I say than other offerings in the market for seekers of the truth.

GuruPrabhu · Post by **GuruPrabhu** » 03 Jan 2011 11:43

Blij to naat be blowing ishmoke. What ij the math-e-matishk of dark en-e-rgy aljo known as coshmologikaal constant?

Bade · Post by **Bade** » 03 Jan 2011 19:39

I think you need to put in some hard work, join a brober madrassa and learn some math-e-matishk rather than spend time with other goats in baba ramdev's cave camplex on barf.

First become gora gunga din before learning gora tachqniues, cannot have it both ways. You got to believe in one djinn or the other.

GuruPrabhu · Post by **GuruPrabhu** » 04 Jan 2011 08:10

Naat very halaal Bade Mian. I went to madarsa-e-wikip-e-dia to learn about dark energy:

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

The nature of this dark energy is a matter of speculation. It is known to be very homogeneous, not very dense and is not known to interact through any of the fundamental forces other than gravity. Since it is not very dense — roughly 10−29 grams per cubic centimeter — it is hard to imagine experiments to detect it in the laboratory. Dark energy can only have such a profound impact on the universe, making up 74% of universal density, because it uniformly fills otherwise empty space. The two leading models are quintessence and the cosmological constant. Both models include the common characteristic that dark energy must have negative pressure.

Note that it only speaks of models -- Blij do not confuse heuristic models with mathematics, Saar.