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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1answer
22 views

Heidelberg University, Beyond the SM

I was searching the internet and saw this http://www.physi.uni-heidelberg.de/Jobs/jobdetail.php?job_id=341, I was wondering if you have any idea about the reputation of this institute and level. I ...
4
votes
3answers
385 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 ...
0
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0answers
30 views

Is it more effective to skim through a topic then go back for details or deeply understand each concept/equation before moving on? [on hold]

For example, you are going through a textbook chapter on rotational motion. You come across the concept of moment of inertia and the relevant equations for the first time. You could skim over moment ...
5
votes
1answer
369 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 ...
0
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0answers
15 views

Demand for computational physicists: outlook in grad school [on hold]

Is there actually a demand for computational physicists in academia or is that just a phoney reason departments use to justify having a mix of physics, math and programming? Question background ...
1
vote
1answer
44 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 ...
-3
votes
0answers
39 views

Can something contain itself? [on hold]

Let's say I have a cardboard box. Let's call it box $A$. I can put things in this box -- I can put my glasses in, my shoes in, or my cat in. Can I put the box in the box? Let's call this "second box" ...
0
votes
0answers
124 views

Definition of the “present” in physics (not “instant”) [on hold]

Instead of wondering about what time is, I'll just assume for the moment that it is a parameter describing the evolution of the universe. Observe then that there is a distinguished/preferred time, ...
0
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0answers
22 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 ...
19
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3answers
2k views

Programming in physics [on hold]

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 ...
9
votes
0answers
1k views

How to keep a bucket of water from freezing by only natural means? [migrated]

Strange question. I am working on a fictional story where a person has to carry a bucket of water for hours during a blizzard. Is there any natural way to keep a bucket of water from turning to ice in ...
0
votes
1answer
37 views

Voltage and volume, same SI symbol, how to discern between the two? [closed]

Both are SI quantities that use the same symbol, namely $V$. It annoys me that I might be working with the wrong unit even though it's easy to see if it's voltage or volume by looking to the whole ...
0
votes
1answer
58 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 ...
0
votes
0answers
11 views

What subtopics should I read in order to understand practical electromagnetism? [closed]

I apologize if this question might be not exactly on-topic here. But it seems related enough, and I found no better place to ask. I'm a student that is fairly behind in his course. I have already ...
0
votes
0answers
50 views

Is it a good time to start or I need to work on some more subjects? [closed]

Is it a good time to start string theory when I did a course on Quantum field theory and on standard model but not the renormalization theory? I used following books: Some chapters of Peskin Some ...
1
vote
0answers
38 views

Difference between maths in physics degree and maths in a maths degree [closed]

I hope this question belongs on this site. If not, please feel free to recommend another site to move it to. Basically, I was wondering what are the main differences between the maths you learn in a ...
42
votes
6answers
3k 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
52 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
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0answers
55 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 ...
2
votes
1answer
56 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
44 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
32 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 ...
1
vote
0answers
32 views

All I need to know to enter undergraduate studies in pure physics [closed]

I want to pursue pure physics after my secondary high school. I was wondering if I know all I need to know to get into this stream. So please list out all the topics I need to know before my ...
-3
votes
2answers
113 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
39 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 ...
3
votes
0answers
35 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
47 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 ...
1
vote
0answers
28 views

How does the optimal-gear indicator work? [migrated]

Modern cars like BMW, Ford, Audi come with a system on the panel which tells the driver the next optimal gear to drive. How does it work ? What is the algorithm behind it? What data does it require ...
1
vote
0answers
25 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
80 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 ...
0
votes
1answer
14 views

Affects of static electricity on the heart

I have an electricity problem. I get shocked by just about everything. Metal, plastic, etc. flooring can be wood,tile, carpet,linoleum , it doesn't seem to matter. The ones that go through my ...
1
vote
0answers
87 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
130 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
61 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
62 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
407 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
79 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
78 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 ...
0
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2answers
74 views

What does a unit like $C^{1/5}$ or $kg^{1/2}$ physically mean?

I'm more of a math guy than a physics guy so bear with me.... In fractal geometry, fractals are considered to have fractional dimension. For instance an object such as the Koch curve has a fractal ...
2
votes
2answers
96 views

How are weights and scales used by the public calibrated?

My physics teacher has a set of masses: things from 1 to 10 grams. My chemistry teacher has electronic balances that measures things in grams. In France, there is a block of metal we hope no one ...
1
vote
1answer
88 views

When was the first time that superconducting quasiparticles were called Majorana fermions?

Since a number of years, the field of superconductivity has a growing obsession with Majorana fermions. I wonder how far back we can go: When was the first time that superconducting quasiparticles ...
1
vote
0answers
70 views

What is the next step in math education after taking the last undergrad math course? [closed]

Currently I successfully completed the 3rd semester of my B.Sc. in Physics. Since the upcoming summer semester is starting soon and I'm going to have some spare time I can spend, I want to expand and ...
1
vote
2answers
97 views

What does the “T” stand for in T-duality?

First of all, I am not a physicist. I'm a graduate math student and recently I came across the concept of T-duality. Actually I'm studying generalized complex geometry, which according to this paper ...
0
votes
2answers
111 views

Help with high school physics [duplicate]

I am studying high school physics and it seems i have memorize the equation and use it mechanically in doing question and memorize lots of physical phenomena.I know a lot of physical phenomena can be ...
2
votes
1answer
171 views

What was Feynman's famous formula?

In Welton(1983), Memories of Feynman, Welton mentions two formulas which he denotes as Feynman's Famous Formula (FFF) and FFF #2. Which famous formulas is he talking about? Is he maybe talking about ...
1
vote
2answers
129 views

Sign convention for the Minkowski metric $\eta_{\mu\nu}$

In special relativity, one is confronted with a quadratic form called proper time, which is $c^2t^2-(x^2+y^2+z^2)$, $t$ being time and $x,y,z$ being the space coordinates. One usually introduces a ...
0
votes
2answers
39 views

Usage of singular or plural SI base units when written in both symbol as well as name [closed]

I have multiple doubts related to the usage of singular or plural SI base units when written in both symbol as well as name. I have framed this question under two parts, namely, Part (a) and Part ...
5
votes
1answer
213 views

Physical intuition/interpretation of fractional derivatives/integrals?

Oftentimes, when the derivative and integral operations are introduced within the realm of physics, we are taught some physical interpretation of them: Velocity is the derivative of position ...
21
votes
4answers
2k views

If the LHC-calculated mass of the Higgs is wrong, how long will it take to determine this with confidence? [closed]

After I watched "Particle Fever"--the movie about Large Hadron Collider (LHC) and the successful identification of the Higgs boson--I became a bit concerned with that team's handling of various ...
0
votes
1answer
54 views

Requirements prior to Quantum Mechanics [duplicate]

What are the requirements in physics and mathematics that somebody must have in order to start learning Quantum Mechanics by himself?