212312     ฟิสิกส์วิศวกรรมของวัสดุอาหาร     Engineering physics theory of food Materials

หลักการของการกำหนดรูปทรงและขนาด สมบัติทางกล ทางความร้อน ทางไฟฟ้าและทางแสงของวัสดุอาหาร การวิเคราะห์และการประยุกต์ข้อมูลเพื่อออกแบบระบบการเก็บ การขนย้าย และการแปรรูปวัสดุอาหาร

(Principles of shape and size determination; mechanical, thermal, electrical and light properties of food materials, analysis and utilization of these data for designing of storage, handling, and processing of food materials.)

(212312 มหาวิทยาลัยเกษตรศาสตร์)

 

Shortage of fresh post-graduates prompts institutes to hire their services

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“They are more professional and don’t mind lesser pay package”

‘Colleges need them because they can train young minds patiently’

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HYDERABAD: Strands of grey hair have come of age, literally. Though cause of great frustration, they are also much sought-after these days, especially in the field of education. Teachers of a few subjects such as Mathematics, physics theory, Chemistry and English are finding takers even after they have been officially retired by their previous employer—government in most cases.

With recent introduction of basic sciences into the curriculum of Hyderabad Jawaharlal Nehru Technological University’s engineering courses, the demand for lecturers in physics theory and Chemistry has gone up considerably. Majority of the colleges are hiring retired lecturers to teach these subjects, as fresh postgraduates in basic sciences have come down in numbers. “With increase in the number of engineering colleges and the high demand for IT-related jobs even among graduates till recently, students stopped opting for postgraduate studies in these subjects. The few available competent lecturers are taken by corporate colleges. Hence the rush for retired lecturers,” says a physics theory lecturer.

The largest recruiters of retired lecturers are engineering and medical colleges because they require professorial faculty, hardly available among younger people.

“Private colleges cannot match government in payment and hence, cannot lure experienced lecturers out of government service. Instead, they try to tap the knowledge of the retired professionals who work better, and wouldn’t mind lesser payment,” says M. Krishna Murthy, principal of a corporate college in Vijayawada.

Experience counts

English lecturers are perhaps the most privileged lot, with many openings. “Majority of the postgraduate students these days learn from guides to pass the examinations, never caring to read the original Shakespeare or Milton. Retired lecturers obviously have an edge over them,” says M.A.Wahid, a visiting faculty at JNTU . “It is not only about money. Only lecturers with good knowledge and passion for teaching opt to work after retirement. Colleges need them because they can train the young minds patiently,” says K. Andhra Dev, who works part-time for Narayana institutions.

Death from the Skies!:  The Science Behind the End of the World, by Philip Plait, Ph.D. — This is a terrific read for anyone who loves space, science, reason, and disaster porn as much as I do.  The Bad Astronomy blogger explores scenario after scenario with a flair for gruesomeness and a clear head for the probabilities involved.  The Washington Post called it “strangely comforting,” and they’re right.  It makes me feel about impending-albeit-statistically-improbable doom exactly the way I feel when watching Alex Filippenko talk about the same topics on The Universe:  one of these days we’re all gonna DIE, but it’s so interesting and cool that you can’t help but smile.

(source)

 

The data as we know it is represented by the following photo and statements below that were concluded at the end of class on 11/19.

Red Graph #1 represents the position of the basketball along the y-axis (vertical movement) while Red Graph #2 represents the position of the basketball along the x-axis (horizontal movement). Blue Graph #1 represents the velocity of the basketball in Red Graph #1 while Blue Graph #2 represents the velocity of the basketball in Red Graph #2. These graphs allow us to conclude that the vertical movement (linear) of the basketball is that of a constant velocity model. while the horizontal movement (parabolic) of the basketball is that of a constant acceleration model.

While the basketball is in the hands of the person, the free body diagram consists of the ball (system), the force of gravity (downward arrow) and the force of the throw (diagonal arrow) however, when the ball is in motion, the only force acting on the ball is that of gravity (downward arrow). Finally, when the ball is caught, the forces acting on it are the force of gravity (downward arrow) and the force of the hand (upward arrow).

The motion map we came up with consists of two parts. The red arrows pointed to the right represent the constant acceleration of the basketball and the red arrows pointing downward represent the force of gravity that is applied to the ball while it is in motion. The blue arrows are congruent to one another and represent the horizontal motion of the basketball.

Nadie lo sabe. El impacto de la sonda LCROSS ha levantado una nube de polvo en la que se ha detectado agua. Ha saltado la noticia en toda la prensa, pero la cuestión del título, ¿cuánta agua hay?, no es fácil de contestar. Richard A. Kerr nos cuenta hoy en Science que realmente no se sabe. Algunos investigadores creen que hay más agua que en el desierto del Sahara, pero no saben realmente cuanta más. Quizás un 1% en volumen en los primeros 3 metros de profundidad. Valores entre el 0.1% y el 10% también son compatibles con lo observado en el impacto. Sólo análisis futuros teniendo en cuenta la orografía detallada de la región del impacto permitirán reducir la incertidumbre en este valor. ¿Suficiente agua para sustentar a una base permanente en la Luna? Realmente la respuesta no importa. Mantener una base permanente a 40 grados sobre el cero absoluto requiere resolver problemas más importantes que el del agua. Nos lo cuenta Richard A. Kerr, “Yes, There’s Ice on the Moon—But How Much, and What Use Is It?,”Science 326: 1046, 20 November 2009.

You may have heard about [possibly in a differential equations lecture or in a physics theory lecture] the following relation

c₀cos(ωt)+c₁sin(ωt)=(c₀²+c₁²)^1/2cos(ωt+φ)

Ever wondered what’s going on? Here I am writing about one way of doing it.

First, consider the following [homogeneous  and linear, too nice huh ? ] differential equation:

y”+ω²y=0

(1)

You know, a set of two linearly independent solutions is {cos(ωt),sin(ωt)}, then any function which satisfies the equation above can be written as a linear combination of cos(ωt) and sin(ωt). Now, observe that Acos(ωt+φ) satisfies (1), therefore,

Acos(ωt+φ)=c₀cos(ωt)+c₁sin(ωt),∃c₀,c₁
(2)

Now the problem is determining the relation between A,φ,c₀ and c₁. We can set t=0 to get some information. We can differentiate Acos(ωt+φ) w.r.t.[with respect to] t and then again set t=0. After a few seconds, the work will be done

Set t=0, therefore get

Acos(φ)=c₀

Differentiate (2) w.r.t. t, and let t=0 to get,

-Asin(φ)=c₁

cos²(φ)+sin²(φ)=1, therefore c₀²+c₁²=A².

Let A=(c₀²+c₁²)^1/2 and φ=arccos(c₀/A) then everything’s okay. Surely, it does not matter whether A is positive or negative, its sign would change the value of φ to φ+π, for example.

The reason which motivated me to write this post is just a little complicated, say, it is a pseudo-motivation. A connection to the blog title has been made, then I can end this post

Take care…

End note: Voila!

Hi there physics theory people!

Here is a great simulator for Projectile Motion
Projectile Motion Simulation

Looking for the God Particle?

Now there is a Test

 

 What occurred within a billionth of a second after the Big Bang? How was our universe actually created? These types of questions have generated a great deal of excitement among the world’s particle physicists and cosmologists for a very long time. The latter question about the origin of our universe has also generated a lot of interest on the part of general public as well. Speculation and explanation as to how the universe was actually created has tended to fall into two categories—scientific and religious.

 These two perspectives may soon cross paths on the road to a final definitive answer of how the universe began. I will explain the fascinating realm of particle physics theory and the interconnection to religious thought about the origin of the universe from both a scientific and religious perspective. I’m going to put forth my ideas using logic and reasoning power as to what the connection is and try to resolve it. It’s a tall order but someone has to do it. My ideas will come at the end of this Blog. For now, the reader needs a little background on these questions and the scientific approach to answering them.

Background

 physics theory is now on the verge (perhaps) of confirming a “Theory of Everything” known as String Theory or M-Theory.  Albert Einstein spent the last thirty years of his life trying to reconcile the physical laws of Quantum Mechanics with General Relativity. It was an attempt to weave together the physics theory of the very large (with concepts like time, space, gravity and huge entities like galaxies, solar systems, and the movement of planets) with the physics theory underlying of the very small (atomic and sub-atomic particles and their motions such as atoms [the smallest unit of any chemical element] and sub-atomic particles [which are the basic indivisible particles of matter, like quarks and leptons]).

 As brilliant as Albert Einstein was, he was not successful with bridging quantum mechanics with his theory of general relativity. In addition to understanding a theory of everything are questions important to understanding the origin of our universe. Without getting much into the theoretical background of particle physics theory, I want to explain to the reader what the scientific questions will be explored with the Hadron Collider.

  It is anticipated that the Hadron Collider will either demonstrate or rule out the existence of the elusive Higgs boson, the last unobserved particle among those predicted by the Standard Model. The particles in the Standard Model make up all the visible matter in the universe. The problem of the Standard Model in physics theory is threefold: (1) We don’t know if all particles are there, (2) it doesn’t tell one how matter in our universe was created, and (3) the model doesn’t account for gravitation, dark matter, and dark energy.

 The God Particle (viewed by some as the Goddamn particle), or more aptly named, Higgs boson, is theorized to have existed in that billionth of a second after the Big Bang and is believed to help most of the particles in the Standard Model obtain their mass at that time. This gets complicated real quick because wave mechanics-particles like photons probably were unaffected by the Higgs boson and simply passed through it at the time of the Big Bang.

The following are some of the important scientific questions to be answered by the Hadron Collider experiment:

Scientific Questions

Is the Higgs mechanism for generating elementary particle masses in the Standard Model indeed realized in nature? If so, how many Higgs bosons are there, and what are their masses?

 Why is gravity so many orders of magnitude weaker than the other three  fundamental forces?

 Are electromagnetism, the strong nuclear force and the weak nuclear force just different manifestations of a single unified force, as predicted by various Grand Unification Theories?

 Is Supersymmetry realized in nature, implying that the known Standard Model particles have supersymmetric partners?

 Are there additional sources of quark flavour violation beyond those already predicted within the Standard Model?

 Why are there apparent violations of the symmetry between matter and antimatter?

 What is the nature of dark matter and dark energy?

 Are there extra dimensions, as predicted by various models inspired by string theory, and can we detect them?

Now There is a Test

 There are efforts that have been underway for some time to answer some of the greatest secrets of our universe. One such effort is known as the Hadron Collider. It is 17 miles in circumference and 570 feet beneath the Franco-Swiss border near Geneva, Switzerland. It was built by the European Organization for Nuclear Research (CERN). It is believed that at the beginning of the universe (in that billionth or trillionth of a second) after the Big Bang Singularity, particle mass was created from energy [remember Einstein’s E = mc² which was a beautiful formula for the interconnection of mass and energy]

 The Hadron Collider’s importance to science cannot be underestimated. Briefly, the Large Hadron Collider (LHC) is the world’s largest and highest-energy particle accelerator, intended to collide opposing particle beams of either protons or lead nuclei. The purpose of doing this is to search for the hypothesized Higgs boson, and the large family of new particles predicted by supersymmetry.

In 2008, the LHC was successful for the very first tine in colliding proton beams, but was halted due to a serious fault between two superconducting bending magnets. Due to repair time the LHC is scheduled to come back online in mid-November 2009. The scientific world is looking forward to the results of the LHC experiment.

 But readers need to know—what does all this mean? Why is it important? If you want to explore this on your own I recommend the following book: The God Particle: If the Universe is the Answer, What is the Question? This book was written by Nobel Prize-winning physicist Leon M. Lederman and science writer Dick Terisi.

The LHC will try to create the Higgs boson again by shooting protons at each other traveling at near the speed of light [approximately 11,000 times around the 17-mile collider in just one second]. The results will be spectacular even if the Higgs boson is not confirmed. Steven Hawking is betting that it doesn’t exist. Non findings would be significant because it means, according to Hawking that, “I think it will be much more exciting if we don’t find the Higgs. That will show something is wrong, and we need to think again….. If the LHC does find supersymmetry, this would be one of the greatest achievements in the history of theoretical physics theory.” Hawking also has said, “It would also be a key confirmation of string theory.”   

 As mentioned at the top of this Blog, there are two basic perspectives on the origin of the universe, one scientific and the other religious. Two subjects modern day physicists haven’t spoken of in relation to the Hadron Collider (but are very much aware of them) has to do with the possible existence of a mutiverse, i.e., a large bubble or sea of universes (trillions upon trillions upon trillions of them with no limit) and consistent with such a notion as a multiverse is the concept of forever.

Whenever I’ve tried to conceptualize these two ideas (multiverse and forever)—it has raised goose bumps on my spine. The Hadron Collider is an impressive step forward among particle physicists and cosmologists in their ability to understand our universe. But what I’m going to discuss now is the concept of forever, and what, if anything, a religious perspective can contribute to our understanding of forever as a concept. These are my original ideas.    

Exploring Hypotheses Regarding God and the Universe

 Karen Armstrong described in her book, The History of God, how the concept of God changed over time in biblical scriptures. God changes in meaning over time because man’s relationship to a God changes over time. One of the biggest changes enacted by religious followers of Christianity occurred in the Fourth Century (325 C.E.) when the bizarre concept of the Trinity was created to settle the question of Christ’s humanness versus his alleged divinity.

This profound change in the ‘divinity’ status of Christ paralleled many of the changes that occurred among the pantheon of polytheistic Gods that people worshipped in the ancient world. Pagan religions and Christianity were very similar in creating anthropomorphic images of themselves and the God(s).  The many gods of paganism and polytheism attributed human characteristics to their gods; by contrast, Christianity attributed human characteristics (male gender, emotions like love, anger, jealousy and rage) to their monotheistic God. If God is unknowable or incomprehensible then how did the writers of the Bible attribute so many human characteristics to God?

 But Christianity took it one step further and made a man of human flesh and blood into a god when the concept of the Trinity was created. These changes were all about images that were very much anthropomorphic. The idea that God is not because He transcends all being was never considered by the Christian traditional perspective.

It is said in many locations throughout the Bible that man was created in the image of God. What was meant by this? The idea of image was not something new to the ancient world in which Christianity developed. Many of the images that arose in connection from the many Gods of Paganism (polytheism) were of animals, or the sun or the planets.

 Christianity attributed a one creator God of the Universe with purely human characteristics. This Christian act is only one step beyond polytheism. By doing this, man essentially was placing himself at the center of his own universe. At that moment— mankind took ownership of the universe. Not wanting to appear egotistical, he substituted himself with the term God, which is the embodiment of man himself.

 By creating an externalized image and calling it God, man could use that idea to make sense and order out of man’s existence. He could following this then make sense and order out of the universe. Ancient peoples desire to make sense of the universe parallels modern day scientists desire who also want to make sense of the universe. It is an enviable goal—but religion and science  just do it differently. Religion is all about Mythos and the attribution of meaning, and Science is all about Logos, a search for rational explanations, based on facts, theories, and  real world observation and data collection on maturalistic phenomena. As explanations go, science in the modern era is now in the driver’s seat. Religion, and religious explanations (natural theology) is a passenger in the back seat.

 Scientific theories of the universe, and their extraordinary complexity, all point to the possible eventual comprehensibility of our universe. There exist the possibility that our universe had no beginning and will have no end and that the laws of physics theory resulted in a self-contained universe.

Despite its eventual darkness and infinite expansion, it will go on forever. To say that something always existed and will always exist is to cause goose bumps on one’s spine. This occurs because man has difficulty fathoming the concept of infinity or “forever.” It is a “mind-boggling” concept.

The concept is difficult to fathom because our everyday experiences on this earth run counter to it. That is, everything we see, hear and experience in everyday life has a beginning and an end. The seasons come and the seasons go. People are born, live their lives, and then they die. There is nothing very sentimental about reality in that regard. However, the concept of forever is extremely difficult to grasp. The idea that something always existed is equally troubling. Why? Because it is certain that such a concept of forever is indeed outside our everyday experience.

M-Theory and String Theory suggests the possibility that perhaps there are trillions upon trillions of other universes all with their own big bangs and singularities that occurred. Or, perhaps the laws of physics theory differ from universe to universe, meaning their creation occurred in some other way.

If you can imagine for a moment the idea that the future will go on forever, and that the past “goes back” forever, one is confronting the impossible task of understanding the past from the future, but also by default trying to understand what the concept of   “present” really means in that context. If there is, as Albert Einstein suggested, a space-time continuum where neither space nor time are separate entities, then perhaps there was no creation in the first place if one cannot ever separate space from time.

If one remembers their college physics theory class, then one must remember the Law of Conservation of Energy. That is, neither matter nor energy can be created or destroyed. They are the same thing. What makes them different is that they are simply different forms of the same thing.

If our universe (or any of the other trillions upon trillions of universes) had no beginning and will have no end, and the past goes back forever and the future goes on forever, then that would mean there was no beginning point to any of it. If no beginning point exists (or ever existed), then there is no “creation” or creation point. And if there was no creation or creation point (no beginning and no end) then by definition, there is no need to attribute or invent the need for a supernatural creator. Why? Because there wasn’t a “creation” in the first place that a creator would be needed for. The singularity at the beginning of our inflationary universe may have come about because a parallel universe rubbed up against another universe, thus initiating the big bang singularity and our universe.

The idea of the mock interview is for us to have an Oxbridge-style interview with someone we’ve never met before. These took place at Latymer Upper School (on King’s Street), and my interviewer was from St Paul’s Girls’ School.

I went into the interview room and the first thing I was asked was why I wanted to apply to Oxford for physics theory, at which point I explained that actually I was applying to Cambridge for Phys Nat Sci but due to an error I was down for physics theory at Oxford. He said it was fine and didn’t actually let me explain why I wanted to apply for my course, and straight away asked me to differentiate a pretty standard quadratic. I did it and predicted the next question would be to do it from first principles (which it was). I got as far as the second line (writing Lim(Dx→0){the entire mess before it simplifies}) before he cut me off and asked me whether I knew about radioactive decay. I cautiously said yes, at which point he asked me to write down the equation, then derive it from first principles. I wrote down the ODE, separated variables and proved the formula. He then asked me what I knew about how calculus was conceived. I hadn’t gone to the Newton/Leibnitz Maths Soc lecture but I knew enough about the history (thank you Simon Singh!) to say that they had independently invented calculus at the same time. He asked me what Newton was researching at the time and I said gravity, and was about to go into detail at which point he asked me what I knew about Leibnitz. I confessed that I didn’t know much about him, and he said it’s fine – ‘he’s a mathematician – nobody really cares what they were researching’ (in case readers haven’t already worked it out, he was playing bad cop). He asked me why it’s impossible to say who was the first to invent calculus (which I at first misinterpreted and talked about the different notation which I was going to relate back to something but I now forget) to which I talked about research taking time and that they probably each took lots of time to formulate calculus, and it can’t just be proven who was first by who was the first to submit the paper. He implied it was really about fast communication and he asked whether I knew how research is now distributed. I talked about papers being published online (the arXiv logo jumped to mind though I didn’t mention it) at which point he asked me what scientific papers / magazines I read. I said New Scientist and Scientific American (I could have mentioned physics theory/Chemistry Review etc. but I didn’t for some reason), and he asked me to talk about an interesting article I read recently. I started enthusing about this awesome article I’d read in Sci Am about semiclassical gravity – formulating QFT on the hyperbolic geometry of general relativity and possibly proving singularities cannot be formed. Before I could get to the crux of the issue (dark stars, repulsive forces etc.) he asked me what I knew about dark holes. I started talking about singularities and he asked what terminology I know concerning dark holes. I said a list including accretion disks, Hawking radiation, event horizons. He asked me to define all of those. I defined the event horizon, then started talking about an effect which had nothing to do with Hawking radiation (axial plumes coming from the dark hole, with an accompanying utterance about conservation of angular momentum and fast spinning) but saved myself just in time and said something about virtual particles being created and destroyed. I mentioned proving virtual particles with the Casimir Effect just before I got to the crux of Hawking Radiation, at which point he interrupted me again to explain the Casimir Effect. I said what I knew – something to do with an attraction between two metal sheets.

At approximately that point he said ‘that’s it’ and that I did fine. He explained he’d been playing [not his words] ‘bad cop’ (by then I’d worked out that either that was the case or he was just in a really bad mood because everything was behind schedule (!)) and that I reacted well under that. There’s a reason I’ve written all that in one paragraph – the interview felt exactly like one continuous rush of me going through almost every bit of classical (and some non-classical) physics theory I’ve ever come across in half an hour (it felt a lot shorter than that)! It felt a bit like some of the ‘Achilles and Tortoise’ recursion stories out of GEB by Hofstadter in that he kept cutting me off before I could finish one thing, but as it turned out that was the whole point.

At some point he also asked me about the difference between resistance and resistivity (object vs intrinsic material property) and I asked whether I should write the equation connecting them at which point he said ‘yes that might be nice’. He must really get a kick out of playing bad cop! He then asked what causes resistance and what happens to resistivity when you heat something – I drew the approximate structure of a metal and talked about electrons hitting metal cations, and that when temperature rises the cations vibrate more. He asked me to be clearer about ‘more’ – I said greater amplitude and hesitated on saying greater frequency trying to remember the SHM equation for energy (I thought I might have been being ‘browbeaten’ into assuming frequency would increase and in my panicked state I couldn’t remember properly!). I must have said something about SHM and he asked me what that was – I wrote the ODE and said what it meant in words (forgot to write it in x=(x0)sin(wt+phi) form), to which he said nothing and moved on. I can’t remember how that episode fitted in, so I left it out of the mega-paragraph.

Anyways overall, I almost hope my Cambridge interview ends up going like that. I feel I’m now more resistant to intimidating interviewers and have read relatively widely so an interview basically inviting me to talk about what I know about physics theory until I run out of breath and pass out on the floor (Calvin & Hobbes reference) would be pretty much perfect. He didn’t actually ask me to solve any physics theory problems, which was not what I was expecting, but hey.