Questions that ask about some aspect of physics research or study which doesn't involve the actual physics. In general, soft questions can be answered without using physical reasoning.

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3answers
124 views

Meaning of invariable

Invariable means which is not variable i.e. can't be changed. Recently I have seen a sentence when reading a chapter based on measurement: The accepted standards must be accessible to those who ...
1
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2answers
31 views

Do unmeasured particles function the same as when measured?

If there are particles that we are uncertain of are in a state of superposition, do they still function as they would when they are measured? For instance say there is a mechanical clock, and the ...
7
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1answer
239 views

Reference Request: Classical Mechanics with Symplectic Reduction

I am trying to find a supplement to appendix of Cushman & Bates' book on Global aspects of Classical Integrable Systems, that is less terse and explains mechanics with Lie groups (with dual of Lie ...
2
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1answer
168 views

Analyse astronomical data

Recently I was told of a job offer to analyse astronomical data. The job offer states that they want somebody with knowledge of astronomical data analysis software and it will be a plus somebody who ...
1
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1answer
82 views

Why the original BB84 paper “Quantum cryptography: Public key distribution and coin tossing” has 'withdrawn' status?

The original paper proposing quantum key distribution protocol (now known as BB84): Charles H. Bennett, Gilles Brassard, Quantum cryptography: Public key distribution and coin tossing seems to ...
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1answer
83 views

How far do atoms move in a wire when whirling it horizontally?

so the question is: I whirl a mass m attached to a wire with length L and diameter d around my head in the horizontal plane. The mass takes t seconds to move around a circle. How far do the ...
0
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1answer
23 views

Conversion of energy to matter or antimatter?

We all know that matter converts into energy, but will energy convert into matter? Does it form antimatter by converting? Illustrate me with example.
-1
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1answer
30 views

Could each non-dependent physical contant represent dimentions, and our universe be a point on this n-dimentional structure?

For example say the gravitation constant instead of equaling G, was actually a range bounded between 0 and infinity. Our Universe would be at a point on this range (equal to our G value) where ...
-1
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1answer
188 views

How is gravitational force is compared to flow of water?

I listened to a lecture. The professor said that the gravitational field around the particle (spherical in shape) can be compared to a pond having a constant height and depth and water is constantly ...
-2
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1answer
91 views

Do Physics concepts build on top of other concepts?

I am taking a calculus based physics class and I am struggling. I am wondering if I do not understand some concepts, will I be unable to understand future concepts introduced in the same class? In ...
6
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0answers
43 views

What is the importance of studying degeneration on $M_g$

Let $M_g$ be the moduli space of smooth curves of genus $g$. Let $\overline{M_g}$ be its compactification; the moduli space of stable curves of genus $g$. It seems to be important in physics to study ...
5
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0answers
185 views

Semiclassical QED and long-range interaction

I'm interested in the (very) low energy limit of quantum electrodynamics. I've seen that taking this limit does not yield Maxwell equations, but a quantum corrected non-linear version of them. If ...
3
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0answers
66 views

Are scalars starting at around 1300 MeV analogous to some kind of sound in the vacuum glue?

Are scalars starting at around 1300 MeV analogous to some kind of sound in the vacuum glue? Background: There are scalars starting at around 1300 MeV which are probably some combination of ...
2
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0answers
47 views

Dingle vs. Bondi: Twin Paradox Debate on BBC radio?

Herbert Dingle and H. Bondi debated the twin paradox on BBC radio before 1971. Does anyone have a link to the audio of this debate? thanks
2
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0answers
35 views

Kolmogorov entropy and noise

There are various ways of calculating the Kolmogorov entropy (KE)of dynamical system. According to Pesin's theorum, it is the summation of the lyapunov exponents; frominformation theoretic concet, it ...
2
votes
0answers
24 views

What were the immediate consequences Yang-Lee work on Weak Interaction?

I am studying the history of Modern Physics and Yang-Lee earned their Nobel the next year after the Cobalt experiments. I am familiar with the chronology, but am not clear what those findings meant to ...
2
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0answers
119 views

Why supra-conductivity became super-conductivity?

The original article by the Kamerlingh Onnes team in Leiden does not give a name to the new effect: Kamerlingh Onnes, H. Further experiments with liquid helium. C. On the change of electric ...
2
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0answers
79 views

Where to find probability density plots for all elements?

Does anyone know where I can find something similar to this, but for all elements? I would love to find something with the same image quality. Also, is there any software that can produce images ...
2
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0answers
57 views

Are there any connections between James–Stein estimator and quantum mechanics?

Very nice statement from wiki: When three or more unrelated parameters are measured, their total MSE can be reduced by using a combined estimator such as the James–Stein estimator; whereas when ...
1
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0answers
127 views

Story about a mathematician, a dinner party, and the three-body problem

I remember dimly hearing a story, coincidentally also at a dinner party, and I was trying recently to track the details down with no success. I was hoping someone here might have also heard this story ...
1
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0answers
28 views

What causes charge buildup in a cloud before a lightning storm?

I am curious what causes the charge build up in a cloud before lightning occurs. I have seen in a few places such as this, that the process is not fully understood. Is this some form of static ...
1
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0answers
33 views

Logistic map and attractors

Does the logistic map have a strange attractor for some "chaotic" values of the parameter?
1
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0answers
181 views

Introductory exercise set with solutions for string theory

I am trying to self-study string theory, beginning with Ibanez and Uranga (String Theory and Particle Physics). Unfortunately, the book contains no problems, so I'm not sure whether I am fully ...
1
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0answers
46 views

Benefits of the sign convention for electrons?

Benjamin Franklin considered electrons to be positive, but J.J. Thompson considered them negative. We obviously went with J.J. Thompson's convention. Why? What were the benefits of moving to J.J. ...
1
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0answers
54 views

Present experimental status of Moffat's Modified theory of Gravity

Modified theories of Gravity have been discussed before in this 2-year old question, Are modified theories of gravity credible? I was going through Moffat's modified gravity, given in ...
1
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0answers
49 views

Why are polymer representations called “polymer representations”?

Why are polymer representations called "polymer representations"? Polymer representations deal with non-continuous unitary representations of groups acting on nonseparable Hilbert spaces (see e.g. ...
1
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0answers
110 views

Wormholes and the illusion of time?

I was watching a video on Youtube by Brian Greene, "the illusion of time."http://www.youtube.com/watch?v=j-u1aaltiq4 In that video, he introduces to me the idea of a "brane," or a slice of the ...
1
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0answers
317 views

Starting string theory studies in grad school

How is it possible for a grad student to do research in any modern area of string theory like AdS/CFT or ABJM if they need to start grad school by having to learn QFT from scratch? Is there a ...
1
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0answers
141 views

What are the prerequisites to study CP violation?

If one would like to study CP violation, what would be the prerequisites for it? For example, until now I have not studied quantum field theory and have done very little classical field theory, but ...
1
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0answers
219 views

Is the conclusion that the cosmic burst observed in the Draco constellation from gamma rays that are streaming towards a massive black hole correct?

Referencing this news article: http://www.smh.com.au/technology/sci-tech/cosmic-burst-in-far-away-galaxy-puzzles-nasa-20110408-1d6kz.html It also references an event id: (GRB) 110328A The article ...
0
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0answers
12 views

Conceptual questions about chaotic signals

Are chaotic signals stationary or non stationary signals? They are ergodic and ergodic signals are a kind of stationary signals. But, from statistics point of view, are chaotic signals classified as ...
0
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0answers
27 views

Dirac sea entanglement

The theory of the Dirac sea is in disrepute, but I still wonder about it sometimes. In this theory, the particles are all electrons, and obviously an electron with positive energy can be entangled ...
0
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0answers
60 views

Coupled Oscillation Simulation

I'm looking for an online coupled oscillation simulation. The best I have got so far is this --- https://phet.colorado.edu/sims/normal-modes/normal-modes_en.html But I'm looking for something which ...
0
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0answers
27 views

Textbook on Diffusion and Diffusion NMR Spectroscopy

I am looking for textbooks ( Mathematical / Theoretical Physics ) that cover diffusion in general. Although it is not necessary that your recommendation covers it, I am also particularly interested ...
0
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0answers
27 views

Relationship between phase space volume and dynamical entropy

I would like to know if there is any analytical proof or relationship which can show that for a dynamical system in presence of chaos signal, if the phase space volume (PSV) minimization leads to the ...
0
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0answers
63 views

How to move from Special to General Relativity

I have understood special relativity nicely, and right now I am trying to learn general relativity from D'Inverno's book. I an finding it rather difficult to understand the pre-requisite math (i.e. ...
0
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0answers
32 views

Modified Arrhenius equation source? year proposed?

I was curious to know when was the first time (which year) the modified Arrhenius expression was proposed: $k=A(T^n)e^{\frac{-Ea}{RT}}$. I know that the simple Arrhenius equation ...
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0answers
29 views

References requested on departments with recitation sessions

What physics departments offer recitation sessions for their physics courses on the undergraduate level? If there is a site which has such info it will be greatly appreciated.
0
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0answers
34 views

Have there been more distinctive names suggested for neutrino mass states $\nu_1, \nu_2, \nu_3$?

The different mass states of neutrinos are generally named $\nu_1, \nu_2, \nu_3$. By comparison, the names of quark mass states (up, ...
0
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0answers
76 views

Why are there no explicit calculations in some articles

I am always baffled how in all the articles (theoretical ones), there is no explicit calculations, or at least some reference how to find it, or where to find it (the calculation). I get that, for ...
0
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0answers
43 views

Finding a paper about error analysis in DNA sequencing in solid state nanopores using entropy meta-heuristics

I attended a talk at the APS March Meeting in Baltimore with the following abstract: http://meetings.aps.org/Meeting/MAR13/Event/186412 I have been trying to find a paper that covers the topic of ...
0
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0answers
66 views

Did Planck said that his theory is distinct from Zeno's paradoxes?

I remember once reading that Planck or some other prominent figure in quantum physics said that the theory (probably Planck length or Planck time in particular) is not about the thing what Zeno's ...
0
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0answers
957 views

Studying from “Berkeley Physics Course Volume I - Mechanics”

I'm a first year physics student and the main source for our Physics I course is "Berkeley Physics Course - Volume I." I'm having a hard time understanding this book because it assumes a pretty high ...