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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2
votes
0answers
92 views

Mathematician learning theoretical physics [duplicate]

EDIT: I was aware of the supposed duplicate. But I'm interested in a clear and focused path through the basics to advanced theoretical physics such as string theory - a path that avoids studying ...
0
votes
2answers
69 views

What is the meaning of this definition of potential energy?

The isolated system of particles is being observed. In the coursebook, $\vec F_\mu$ is by definition the vector sum of forces of all other particles acting on $\mu$-th particle. Usually, potential ...
0
votes
1answer
154 views

A course in Lagrangian Mechanics [duplicate]

I would like to know: what are some of the best introductory books to Lagrangian Mechanics?
0
votes
0answers
33 views

Can anybody recommend a book on quantum physics for a mathematically minded student? [duplicate]

Basically what the title says. I'm a math/physics double major going into my second year, but I'm much more math oriented. I'll be taking a quantum class in the fall and I'd like a book that ...
2
votes
0answers
14 views

Is there any good literature about conceptual designs of Quantum (Micro-) Black Holes Machines?

I did some research and found this book: Quantum Black Holes, 2014 http://link.springer.com/book/10.1007/978-3-642-38939-9 It seems good for a repetition of current status of (Quantum) Black Hole ...
3
votes
1answer
131 views

Was quantum mechanics made to fit the Bell violations or they just happen to fit them?

Entangled bipartite states can violate the CHSH inequality upto $2\sqrt{2}$ with suitable measurements. Is it that in nature we don't witness violation of CHSH more than this and quantum mechanics ...
2
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0answers
126 views

Piezoelectric effects of naturally shaped quartz crystal for maximium Q?

Background Based on helpful comments and links here and also from my question on the electronics stackexchange, I have learned that the quartz crystals are nature's transducers of energy, allowing ...
0
votes
0answers
18 views

Need your Kind Recommendations and References Please [duplicate]

I studies Physics in my high school about 5 years back and i have never touched physics after that.I am planning to revise that very soon. I am now planning to do college physics on my own at my home ...
0
votes
1answer
161 views

Are Feynman's Six Easy Lectures still relevant today?

I haven't learned anything about modern physics at the university yet, but next year I will, and in the summer before I thought I would read this book, Six easy lectures from Richard Feynman. It was ...
0
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0answers
47 views

When doing E&M problems, I find the extreme exponents annoying. Could redefining the coulomb change this?

When typing into my calculator things like 9e9 or 8.85419e-12 its rather annoying to write in all those exponents (yeah I know ...
0
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0answers
39 views

Radial excitation and orbital-angular momentum excitation

Sorry. Just want to make sure, but what does radial excitation and orbital-angular excitation mean in the context of bound states? Just higher $n$ and $\ell$ quantum number?
-5
votes
1answer
92 views

Does gravity slow entropy? [closed]

Just got to thinking about why time slows in a gravitational field. It occurred to me that, in a gravitational field, the closer you get to the source the slower time seems to travel. But also, the ...
1
vote
3answers
626 views

Is net work and total work same?

According to my text book Total Work = Delta Kinetic Energy = KEf - KEi But then work is defined to be dot product of Force (vector) and Displacement (vector). Also to my knowledge work is ...
0
votes
1answer
65 views

Algebraic properties of fundamental physical constants

A few weeks ago I started wondering if there's any reason for a given fundamental physical constant, like Boltzmann's one, to enjoy some algebraic properties, for example being rational/irrational or ...
1
vote
1answer
58 views

Superscript on density matrix

I have been asked in homework to solve the optical bloch equation for the initial condition of $\rho_{22}=0,\rho_{12}=0$. Professor gave a hint of the general equation and let us carry it from here. ...
2
votes
2answers
57 views

Is Venus in the habitale zone of a robot (transistor CMOS brain, metal body) ? Any definition by NASA?

So the robot's information-processor works based on CMOS technology, the energy is powered by lithium-ion battery/solar and the body is made of stainless steel. For reference you can think of the ...
2
votes
1answer
209 views

Learning physics from a strong math background? [closed]

I have a master's degree in operations research and took several PhD level math courses. In particular I'm most familiar with analysis/measure theory, probability theory, and stochastic processes, and ...
7
votes
2answers
10k views

What is the difference between a “model” and a “theory”?

In my past questions I have used the terms "model" and "theory" interchangeably. So we have statements along the lines of The Standard Model is our best theory of particle physics but I have also ...
1
vote
1answer
115 views

Order of index in Lorentz transform

I am reading Schwartz's "QFT and the standard model". On pg 13 he gives the Lorentz transform of a rotation around the x-axis: $ \left( \begin{array}{cccc} 1 & 0 & 0 & 0 \\ 0 & 1 ...
-1
votes
2answers
69 views

What are the consequences of a non-computable universe?

I have seen that is is debated if the universe is digital, computable or non-computable. what specific consequence could this have in the format of the laws of physics? Or would that mean that we will ...
1
vote
3answers
134 views

“Complete” confusion

The word "complete" seems to be used in several distinct ways. Perhaps my confusion is as much linguistic as mathematical? A basis, by definition, spans the space; some books call this "complete" -- ...
2
votes
0answers
143 views

Why does regularization work in this Bessel function integral?

I encountered some days before an integral representation for a modified Bessel function and should differentiate it. But in this representation : $$K(\omega,a)=\int_0^{\infty} \frac{ds}{s} ...
1
vote
2answers
131 views

Why can't we precisely define physics? [closed]

While reading a textbook, I came across this statement: "A precise definition of physics is neither possible nor necessary." I was curious why it is not possible but the textbook never ...
1
vote
1answer
87 views

Quark-gluon plasma: status [closed]

Can we say that a QGP has been observed or is there only suggestive evidence? Is the idea that string theory, through the AdS/CFT correspondence, could help to understand this new state of matter ...
1
vote
1answer
237 views

Is 'Boltzon' an accepted name for particles following Maxwell-Boltzmann (MB) statistics?

In my curriculum during one of my statistical mechanics visiting lecture classes, our teacher was referring comparatively macro particles following MB statistics as "Boltzon". But I have searched ...
6
votes
3answers
512 views

Explaining a quote by Weinberg about the signifcance of symmetry groups in physics

When skimming through a book, I found this quote: The universe is an enormous direct product of representations of symmetry groups. —Steven Weinberg I am a mathematician (so I know only basic ...
4
votes
1answer
488 views

Does “finite” include zero?

Infinity, is clearly not finite. But there is some dissent on whether or not zero is finite. I have seen authors use "finite" to indicate the value of $0$ is excluded as well as infinity. Is there ...
1
vote
1answer
75 views

Understand the relation of time and the space dimensions of spacetime?

I assume the relation of the three spacial dimensions and the time dimension is handled purely in the mathematical domain, usually. But is there any intuitive description of this relationship, how ...
0
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0answers
177 views

Exercises with solutions in dimensional analysis - reference request

I am currently trying to brush up on my skills in dimensional analysis, and computing with units. Is there a good source of worked examples, and exercises with solutions? I'd prefer to have solutions ...
21
votes
3answers
3k views

Programming in physics [closed]

How important is programming in physics? I am studying physics at university and these first years there is actually no approach (as it is understandable) to what working in physics is like. Now, I ...
0
votes
1answer
133 views

What physical properties can we measure most accurately?

As far as I am aware, frequency is the most accurate physical property we can currently measure. This has led us to very high standards of experimental verification of e.g QED predictions and the CMB ...
46
votes
6answers
5k views

What physics paper would a high school student be able to read?

I'm looking for a physics paper which a typical high school student who is new to physics would be able to read and grasp the general idea of the purpose, setup and results, if not the details. To be ...
0
votes
1answer
397 views

Laplace-Beltrami vs d'Alembert operators in flat vs curved space-time

I am confused with the difference between Laplace-Beltrami (LB) and d'Alembert operators in flat/curved space-time. d'Alembert operator in flat space-time (Minkowski) is defined as $$\Box= ...
0
votes
0answers
170 views

What is the meaning of symbols $\delta f$ and $\delta^2f$?

Professor was using these symbols to derive the continuity equation. He defined the infinitesimal mass as $\delta^2m=\rho \delta V$ and the mass that leaves some closed boundary $\partial V$ as ...
3
votes
1answer
291 views

Statistical Mechanics vs Statistics

Just how much of a representation of statistics do we get in a statistical mechanics curriculum. What are some of the useful facets of stat not in stat mech/quantum mech that physicists should really ...
3
votes
3answers
254 views

What is nuclide notation referring to? Only the nucleus or the whole atom?

sorry that this is an easy question but I am just a bit confused about nuclide notation. When you say e.g. $^{240}_{94}\text{Pu}$, are you referring to the atom of $\text{Pu}$ or only its nucleus? It ...
1
vote
2answers
368 views

What does excitation in an atom mean?

This is not regarding the definition of excitation itself. What I'm having trouble with is the difference between "electron excitation" and "atom excitation". When I electron inside the atom gets ...
-2
votes
2answers
124 views

Using mega (=10^6) when writing by hand? [closed]

I just solved a problem which had answer 1.7*10^6 m (m=meters) If I wanted to write this using M=10^6 it would be 1.7 Mm, which if I write it by hand would look like "1.7 mm" which is confusing. Is ...
1
vote
1answer
119 views

Rain system movements and highways?

In my free time I sometimes enjoy watching the weather or radar and trying to predict how a rain system will move. Pretty often I notice that a small rain system or even a large one will congregate or ...
4
votes
0answers
88 views

Are the fundamental constants of nature independent?

Background: I am a layman and I just watched the video "Infinite Worlds: A Journey through Parallel Universes" (http://www.youtube.com/watch?v=OO4uzgiRHkE) featuring a discussion with Andrei Linde, ...
4
votes
1answer
73 views

“Hollow Earth” like Theories for pedagogical porpuses [closed]

I recently encountered the Hollow Earth theory, and I realize that This kind of theories can be used to give a really interesting discussion of a physical law. For example, If we take the ...
0
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0answers
31 views

Are there computerized ontologies for Relativity and (Experimental) Physics? How to contribute?

As machines and automation can generally assist humanity in physical activities, and even exceed mere human capabilities, so, increasingly, also in tasks of reasoning. A basic component of the latter ...
1
vote
2answers
115 views

Why isn't all of physics based on other rates of change [duplicate]

Define the jolt/jerk to be $$J(f)={{d^3 f} \over {dt^3}}$$ Why don't we use the concept of jolt more often considering that the change in acceleration is most definitely an important characteristic ...
2
votes
0answers
170 views

What does it mean: “If you scream in Hilbert space, nobody will hear you!” [closed]

This question may not be appropriate for this site and if it so, sorry for that. Today, I have heard the following quote from one of my friends: If you scream in Hilbert space, nobody will hear ...
0
votes
2answers
142 views

Naked Time ( Is there such a thing ?) [closed]

I have lately been concerned with time and whether or not it is an illusion. For argument's sake let's assume it is. Then time should stand on its own. Can anyone describe, (or point me to a paper ...
-1
votes
1answer
105 views

How do you become a theoretical physicist? [closed]

Is there a specific subject at university called "theoretical physics" or do you get a PhD in Physics and then if your job involves theory you are considered a theoretical physicist?
0
votes
1answer
68 views

What is “adjustable constant”?

This is quoted from A.P.French's Vibrations & Waves. Explicit differential form of linear harmonic oscillator is: $$ m\dfrac{d^2x}{dt^2} + kx = 0 \quad \& \quad \dfrac{1}{2} ...
7
votes
3answers
2k views

Why does the lake surface appear darker in some areas?

What causes the surface of the lake to appear darker in some places? Firstly, I know that it's not fishes that cause it. Secondly, the dark surfaces move from time to time and thus are not ...
2
votes
2answers
636 views

What unit system does Fahrenheit belong to?

Wikipedia's page for Imperial Units does not list Fahrenheit. The corresponding page for SI Units lists Kelvin as an SI unit, and Celcius as a derived SI unit. This leads me to believe that ...
2
votes
2answers
186 views

Differential operators in curvilinear coordinates

In the appendix A of Griffith's Electrodynamics text, he cites Spivak's Calculus on Manifolds as a reference more a more complete treatment of taking the gradient, curl, divergence, and Laplacian in ...