Trending questions
246,682 questions
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Speed of light for dummy
I'm trying to understand how travelling at the speed of light messes with time. So pretend there is two planets one light year apart.
We are in contact and plan to do an experiment.
When I say 'go' on ...
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What is the connection between renormalizability and renormalization group classifications?
A quantum field theory can be classified as superrenormalizable, renormalizable, or nonrenormalizable and in the renormalization group an operator can be classified as relevant, marginal, or ...
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Will we get electric shock from water surface if there is an electric leak 1.5 m below?
There is a flood situation happens, and an expert gives advices to defend from electric shock. One of his advices said that “in case that you have to force a way through water, we might cannot check ...
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Does temperature affect a bounce height of a ball? [closed]
Different types of balls
Different temperatures of the ball
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Does Matters Persist in Some Form Forever?
If all particles/matters eventually decay or annihilate in the distant future, will all the matter they once composed persist in some form forever, even after the universe reaches its (all scenerios ...
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Kepler's third law and conservation of angular momentum: apparent fallacy
Angular momentum $L$ of a particle in central force is a constant of motion. So for circular orbit, $$L =mωr^2 = constant.$$
This implies $$ω ∝ 1/r^2,$$ hence the time period of revolution, $$T = 2π/ω ...
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Three stages of physics education? [closed]
The mathematician Terry Tao has written an influential piece about three stages of mathematical maturity: pre-rigorous, rigorous, post-rigorous (see also on Wikipedia). Has anyone identified analogous ...
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Why would I trust the data publish by the particle-physics community? [closed]
In my opinion, the generation of data is so complicated that no external party can check them. If that is true, why would I trust the published data, if they are only checked by parties within the ...
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Theoretical intepretation of 3 configurations of transistor [closed]
There are 3 common configurations of transistors which are: common-emitter (most used), common-base and common-collector. LLM is not giving a satisfying theoretical answer for me so I ask here. Most ...
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Does spectroscopy count as a measurement of electron spin?
There was some debate in my modern physics course about the statement
"The spin of an electron can only be measured in the presence of an external magnetic field".
So far in the course, ...
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Are misters (sprays/atomisers) fundamentally limited by the air pressure?
This question is motivated by whether it is physically possible to have a high-quality mister for cooking oil that does not require a non-reusable pressurized can.
A household spray (as in the picture ...
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Variational Principle for the $\rm H_2^+$ ion
I am following the book "Introduction to the Quantum Theory" by David Park, and I've run into a problem. The text calculates the ground state potential energy of the $\rm H_2^+$ ion using ...
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What if there was a matter that pushes instead of pulling [closed]
While the normal matter pulls things to itself because it bends the space and makes a dent on space what if there was a matter that made the space swell instead of making a dent
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Why is the Four-velocity insufficient to be an arrow of time?
Question edited for clarity.
Matter has a four-velocity. One component of this velocity is always along the time axis, toward the future.
My question is; “Why isn’t this component of the four-velocity ...
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Do all operators which fulfil mathematical conditions in Quantum Mechanics correspond to an observable? [duplicate]
In my understanding of Quantum mechanics, which is demonstrably limited, Operators have corresponding observables. I imagine it like operators helping draw a graph, with probability on the y-axis and ...
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