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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-3
votes
0answers
30 views

Why del operator is called divergence operator? [on hold]

I know the Del operator is called divergence operator. And -Del is called convergence? Please explain why with an example.
0
votes
0answers
36 views

Can beamer presentation can be used at APS meetings? [on hold]

I am asking this question because I couldn't find the answer in the APS site. Can we use a presentation created with latex beamer at the APS (American Physical Society) meeting?
5
votes
6answers
891 views

Do perfect spheres exist in nature?

Often in physics, Objects are approximated as spherical. However do any perfectly spherical objects actually exist in nature?
1
vote
0answers
22 views

Electron/positron annihilation lines in astrophysics

I have a reasonable understanding of electron/positron annihilation, in that it is a collision between a pair of particles, one matter and one antimatter, that generally produces gamma radiation. ...
0
votes
0answers
20 views

Pronunciation of “Luttinger” [on hold]

What is the correct pronunciation of "Luttinger" (Joaquin Mazdak Luttinger). Although he was born and died in New York City, I often hear the German pronunciation (since it's a German name). Can ...
2
votes
1answer
179 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 ...
0
votes
0answers
6 views

Are there any potential pitfalls of deferring admission to a PhD program? [migrated]

I'm currently in my final year of undergraduate study, and will be applying to physics PhD programs (for condensed matter theory) soon. Without going into details, I am convinced that deferring my ...
2
votes
1answer
111 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Why the original BB84 paper “Quantum cryptography: Public key distribution and coin tossing” has 'withdrawn' status?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 ...
7
votes
4answers
10k views

What is the math knowledge necessary for starting Quantum Mechanics?

Could someone experienced in the field tell me what the minimal math knowledge one must obtain in order to grasp the introductory Quantum Mechanics book/course? I do have math knowledge but I must ...
1
vote
1answer
21 views

Simple modelling of seasonal variation of temperature?

I'm really curious about this: What is the simplest (or most simplified) differential equation that accounts for the variations of temperature throughout the year at some point on the northern ...
0
votes
0answers
23 views

Appearance of the recomposition of a given spectrum? [duplicate]

Given a visible spectrum, i.e. a function from the set of visible wavelengths into the set of intensities, I would like to see the color having this spectrum decomposition. Question: How can I do ...
2
votes
2answers
55 views

Mathematical approximation to physics

Why is it often said that any mathematical theory is just an approximate theory of the universe? Wouldn't there be accurate mathematical structures repressing the physical entities of the universe ...
0
votes
1answer
55 views

Upcoming 'things to watch' in physics [closed]

What are the 'things to watch' in physics happening in the next year or so? E.g. A big astronomical event that happens only every n thousand years, or an experiment in particle physics which will ...
3
votes
2answers
1k views

Why metric system uses kilogram as a basic SI unit?

SI system uses all (that I know) measurement basic units as 1 (single) instance: meter, second, ampere, etc, except the KILOgram. It already defined with 1000 multiplier (kilo). It prevents from ...
40
votes
6answers
7k views

What technology can result from such expensive experiment as undertaken in CERN?

I wonder what technology can be obtained from such very expensive experiments/institutes as e.g. undertaken in CERN? I understand that e.g. the discovery of the Higgs Boson confirms our understanding ...
4
votes
3answers
524 views

Intuition for Path Integrals and How to Evaluate Them

I'm just starting to come across path integrals in quantum field theory, and want to get the right intuition for the them from the start. The amplitude for propagation from $x_a$ to $x_b$ is typically ...
2
votes
1answer
31 views

Acceleration format and interstellar units

Calculating with m/s$^2$ is very helpful when dealing with acceleration on the human range, as accelerating from rest at 4 m/s$^2$ for 3 seconds will give a velocity of 12 m/s. g is also a very ...
3
votes
2answers
139 views

Lexical/ontological/semantic knowledge base for physics

(1) Are there lexical/semantic knowledge bases for physics that can be used for automated reasoning and AI (like Princeton's Wordnet and MIT's Conceptnet for common sense English usage)? (2) If not ...
2
votes
0answers
100 views

Mathematical Prerequisites for QFT [closed]

I am curious about which areas of mathematics one should be comfortable with before learning QFT. I am familiar with the "learn-it-as-you-go" approach often advocated in physics, but would like to ...
0
votes
1answer
20 views

Mie theory “upper limit”?

I have read most often that objects experimented with in Mie theory are on a scale not much larger than the incident wavelength (usually a fiber of diameter $5$ microns with an incident wavelength of ...
23
votes
4answers
2k views

Which is more fundamental, Fields or Particles?

I hope that I am using appropriate terminology. My confusion about quantum theory (beyond my obvious unfamiliarity with its terminology) is basically twofold: I lack an adequate understanding of ...
7
votes
4answers
963 views

Why is the Copenhagen interpretation of quantum physics the most widely accepted one?

I've been digging a lot into quantum physics in the last few weeks. I didn't care much about the maths, just about what empirically happens to get a conceptual idea about quantum phenomena. The most ...
0
votes
1answer
38 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.
0
votes
0answers
26 views

Resources on Solar Neutrino Physics

For a project I'm doing for an introductory Astrophysics course, I'm trying to understand the nuances of solar neutrino physics. However, most of what is said while explaining neutrino oscillations ...
7
votes
4answers
993 views

Study Quantum Physics

I'm an aspiring physicist who wants to self study some Quantum Physics. My thirst for knowledge is unquenchable and I can not wait 2 more years until I get my first quantum physics class in ...
0
votes
4answers
43 views

Can the term «shadow» pertain to anything else than light? [closed]

Can the term shadow pertain to anything else than light? Feel free to interpret this question in the widest sense possible.
0
votes
3answers
63 views

The study of the physical universe [closed]

If physics is the study of the physical universe, wouldn't that mean chemistry, biology, neuroscience, zoology, history, economics, sociology, etc, wouldn't they all be subfields of physics? I believe ...
11
votes
4answers
2k views

What happens when we cut objects?

What is the role of the molecular bonds in the process of cutting something? What is the role of the Pauli exclusion principle, responsible for the "hardness" of matter? Moreover, is all the energy ...
1
vote
2answers
35 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 ...
1
vote
3answers
106 views

Motorbike with parachute vs normal skydive

Had a strange discussion in the coffeeroom today. The background was a story about a guy that took his motorcycle to transport himself to the airstrip to do a skydive. Since there is no place to put ...
2
votes
0answers
50 views

Really Struggling in electronics. What to do? [closed]

This is my first post so please go easy on me. Okay. Let me introduce myself. I am a first year undergrad CS student who has to study basic electronic course for one semester. As the title says, I am ...
1
vote
0answers
31 views

Doing theoretical physics after an engineering major? [closed]

Some background: I'm majoring in Electronics and Instrumentation engineering, but I want to pursue theoretical physics. I'm currently In my second year of undergrad engineering. I attend some physics ...
1
vote
1answer
85 views

Why are some variables summed infinitesimally and others aren't?

This is something that has been bothering me and I hope the title kind of makes sense. It may be a stupid question but please be gentle. My question is, let's say we have current: $$I=\frac{dq}{dt}$$ ...
1
vote
1answer
86 views

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

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 ...
7
votes
1answer
247 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 ...
0
votes
3answers
128 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 ...
4
votes
1answer
476 views

What is the meaning of this “let there be light” joke?

A middle school teacher across the restaurant is wearing this shirt, and I certainly don't get it.
1
vote
9answers
188 views

Can I throw a stone through my window without breaking the glass?

As far as I know, most of an atom is vacuum. Therefore, in theory, would it be possible for me to throw a tiny stone through my window without breaking it because no matter actually collides?
1
vote
2answers
69 views

Norsk Hydro and heavy water - what was the perceived threat?

Through various raids and acts of sabotage during WWII, the Allies succeeded in preventing Germany from coming into possession of large quantities of heavy water produced by the Norsk Hydro plant in ...
-2
votes
2answers
65 views

Is the physical design of the human beings the best possible? [closed]

The stature and design of the human body. Is it possible that the best physical structure belongs to a human being? If not. What are the flaws in it and what improvements could be done? Is there ...
15
votes
6answers
2k views

Why should any physicist know, to some degree, experimental physics?

I've been trying to design a list with reasons why a proper theoretical physicist should understand the methods and the difficulty of doing experimental physics. So far I've only thought of two ...
2
votes
1answer
72 views

The Thermodynamic Limit of Quantum Statistical Mechanics & Interpretation of Quantum Field Theory [closed]

The philosopher of physics Laura Reutsche argues in her book Interpreting Quantum Theories (review/summary here: http://philsci-archive.pitt.edu/9493/1/ruetsche-review.pdf ) that a "pristine" ...
2
votes
2answers
56 views

Quantifier problems of equations in physics

Equations in physics are often written without quantifiers. For instance, from time to time we can see the equation $$E = mc^2$$ is casually written down. I am wondering shouldn't it be written ...
-2
votes
2answers
39 views

Ideas for high school physics paper, including simulations [closed]

I have to write, with two friends, a simulation based physics paper at school. The problem is, that will I am quite familiar with the concepts of calculus and algebra, my friends aren't. So, we could ...
2
votes
4answers
373 views

Are Lagrangians and Hamiltonians used by Engineers?

Analytical Mechanics (Lagrangian and Hamiltonian) are useful in Physics (e.g. in Quantum Mechanics) but are they also used in application, by engineers? For example, are they used in designing bridges ...
1
vote
5answers
312 views

Physical applications of matrices and determinants

Other than notation devices, I don't see any direct application of matrices/determinants in physics. For example, they are just a different way to write a partial derivative and determinants find if ...
25
votes
13answers
5k views

Comprehensive book on group theory for physicists?

I am looking for a good source on group theory aimed at physicists. I'd prefer one with a good general introduction to group theory, not just focusing on Lie groups or crystal groups but one that ...
0
votes
0answers
36 views

Im a high school finisher and I want to understand Physics theories [duplicate]

I have finished my A Levels (UK high school exam) , and I have studied Further Mathematics, Mathematics, and Physics in high school. I am really interested in learning about theories of Einstein, ...
22
votes
6answers
3k views

Are there two theories that are mathematically identical but ontologically different?

I have no background in physics but there is a question that has been bothering me, so I'm asking you. Are there at least 2 physical theories that are : Mathematically identical, which means that ...
2
votes
2answers
71 views

Rectifying incomplete popular notions in cosmology

In looking at the answers to this question regarding light from distant galaxies ever being visible to us: Expansion of the Universe, will light from some galaxies never reach us? I came across a ...