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    A Research styles in different branches of Physics

    ' Researchers use "standards" to judge the field, in which they can work efficiently, i.e. work gets completed within time availibility of funds.
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    A Research styles in different branches of Physics

    Are the standards of studying/teaching methods same across different branches of theoretical physics like particle, astronomy and cosmology? For example we observe a lot of tours, events and conferences in institutes of astronomy and astrophysics, whereas particle and cosmologists are mostly...
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    2D becomes 3D when looked at by one eye

    This apple video uses parallax(relative motion of foreground vs background) along with relative size of apples to deliver a partial (In the opening only, when we do least expect) depth experience.
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    2D becomes 3D when looked at by one eye

    This apple video uses parallax(relative motion of foreground vs background) along with relative size to deliver a partial (In the opening, when we do not expect) depth experience.
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    A Amplitude of Decay of mesons

    I understand that the transition K→π conserves parity. While in pure leptonic decay, the quark current transition K→Vacuum does not conserve parity so it must include parity violating operator.
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    A Amplitude of Decay of mesons

    is the amplitude of pure leptonic decay of pseudo scalar meson(say K→ee), while is the amplitude of the semileptonic decay of K→π ee. Kindly explain why does sd replace sγ5d ee in the amplitude?
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    What is the scope of analytical research in astrophysics?

    Nowadays much of the community of astronomy and astrophysics is focused on simulations and data analysis. Thus people, who do not have access to grids and data, must resort to analytical analysis. What are the challenging areas of astronomy and astrophysics that rely on analytical workout rather...
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    2D becomes 3D when looked at by one eye

    For centuries, we are using beauty to see space but with stereoscopic tools, it is time to use space to display beauty.
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    2D becomes 3D when looked at by one eye

    Monocular vision gives only the quality of depth and it needs lots of variation in texture, shading and a strong perspective(not available ideally in photo, possible in painting) to construct a 3d scene. In contrast, binocular vision gives a precise estimate of depth. It only needs a minimum of...
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    Time Dependent Perturbation Theory - Klein Gordon Equation

    Dear i wish to know what is the validity of assumption that the second order derivative of a(t) is neglected. Kindly clarify the issue.
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    Form factors in QCD pole

    Form factors in QCD are given in following form "f(q^2)=f(0)/(1-q^2/m^2)". This expression has a pole at q=m. How do we plot these form factors vs center of mass energy and deal with the pole.
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    A good book for astrophysics&astronomy

    Thanks, looks good to me.
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    A good book for astrophysics&astronomy

    I am a researcher and wish to learn astrophysics(research in dark matter). I have never studied astrophysics or astronomy. I am in search for a book that can guide me (1)How do astronomers predict masses of stars, galaxies and planets, their positions and relative velocities? (2) Also...
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    Transition probability

    Here, is one of the many links. http://moleng.physics.upatras.gr/personnel/Koukaras/download/FermiGR.pdf [Broken]
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    Transition probability

    Take a look into the derivation of transition probability in the case of the constant potential. The derivation shows that the time of the measurement is actually the time during which the interaction potential was switched on. It does not include the time after the potential was switched off...
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    Transition probability

    As i studied Fermi golden rule. It involves transition probability of an initial state transiting to a final state in case of constant potential. As i understand the product of time of transition and the frequency of transition should be very much larger than one in order that the dirac delta...
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    Neutrino detection in super kamiokande

    In Superkamiokande, How does one differentiate between muon being produced by neutrinos coming from upward than the muon being produced by the neutrinos coming from downward. http://hep.bu.edu/~superk/atmnu/
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    Gauge degree of freedom

    Is it okay to classify the angular degree of freedom of a point on a circle as a gauge degree of freedom? (i). One can add 2Pi to angle without changing the position of point. (ii). U(1) symmetry exp (i theta)
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    Quantum field as operators

    Is it correct to express quantum field theory as "operator valued function" or "operator function" to spacetimepoints. Also, how value of field at each point act as a separate degrees of freedom.
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    Notation in Statistics

    I have studied a measurement 2(+0.9 error(written in superscript) and -0.1 error(written in subscript)) in a book that gives statistical value of difefrent parameters . What does this measurement implies. As a normal statistical error is written as (2 +-0.9). For e.g 2-0.1+0.9
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    QCD form factors

    I was working on semileptonic B decays.
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    QCD form factors

    Dear friends, i was working on a hadronic decays. It appears that one has to calculate form factors. These form factors involve some very complex numerical integration. I would like to know if there are some packages available for calculating these form factors.
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    Thesis writing

    I am about to write a thesis. I was just wondering whether Scientific workplace is the best software to write a thesis or MS Word. Any advice wouuld be welcome.
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    Matrix elemnet of pion decay

    I have studied that the hadronic matrix element of pion decay (Pi+->mu+ anti muon neutrino) is given as <0|ubar gamma[mu](1-gamma[5])d|pion>. The vector current does not seem to contribute, because it cannot connect a state of unnatural parity to hadronic vacuum. Only the axial and...
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    Unitarity of CKM matrix

    Dear All I guess we can express it as W-|u>=Vud |d>+Vus |s>+Vub |b> W-|c>=Vcd |d>+Vcs |s>+Vcb |b> W-|t>=Vtd |d>+Vts |s>+Vtb |b> and |d> , |s>, |b> are orthogonal states (not necessary due to GIM mechanism) <u|W-(adj) W-|u>=1, <c,t|W-(adj) W-|u>=0 => V as a unitary matrix Am...
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    Unitarity of CKM matrix

    I just want to express the fact that an up quark can only decay to three down types of quarks only and thus the unitarity of ckm matrix mathematically.
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    Unitarity of CKM matrix

    This is a known fact that CKM matrix, a matrix that is used to connect the weak interaction eigenstates to mass eigenstates is unitary. I have studied that this is due to the conservation of probability. i.e. an up type quark will decay into exactly three type of d quarks, nothing more.
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    Wormhole and relative motion

    I believe (3) may hold in the end. i.e. A correct theory of Quantum Gravity may prevent a wormhole to become traversable in the first place. If there is no travel possible through wormhole, no space like intervals appear in any frame of reference thus effectively excluding the possibility of...
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    Wormhole and relative motion

    You are correct, only the configuration consisting of two wormholes having uniform relative motion with each other and sufficiently close, can form a time machine. This example clearly shows how much problematic is the idea of wormholes with relationship to causality.
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    Wormhole and relative motion

    Roman ring So the configuration outlined above does form a time machine. i.e. Whenever two wormholes of equal length are in uniform relative motion (close to speed of light)and are sufficiently close to each other, such a configuration will form a closed time loop. A signal starting...
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    Wormhole and relative motion

    Consider a wormhole. Suppose its two mouths have no relative motion with each other. Therefore no time difference exists across its ends. It provides a mean to travel faster than "light in normal space". Imagine this wormhole to be at rest in frame "S"(say). If there is another frame...
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    Wormhole and relative motion

    Consider a wormhole. Suppose its two mouths have no relative motion with each other. Therefore no time difference exists across its ends. It provides a mean to travel faster than "light in normal space". Imagine this wormhole to be at rest in frame "S" (say). If there is another...
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