Questions tagged [mass]

The property of an object that determines how much it responds to a force in Newtonian mechanics, and how much it interacts with gravity in the Newtonian framework. Mass also refers to the intrinsic energy of a particle in particle physics.

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Why don't strings have a Planck mass? (version 2)

The Energy $E$ of a fundamental string due to its length $L$ goes like $$E\sim TL$$ where string tension $T$ is given by $$T \sim \frac{1}{l_P^2}$$ (Using natural units $\hbar=c=1$ with planck ...
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Is there any known experimental violation of Einstein's $E=mc^2$?

Note that I am not talking about $E_0= m_0c^2$ but $E=mc^2$, where m is the relativistic mass. I know that one holds for stationary particles, moving particles, even light, I read that it even holds ...
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Why don't strings have a Planck mass?

I understand that strings have a size of roughly the Planck length $l_P$ of $10^{-35}$ m. If that is the case then one would expect that their mass would be roughly the Planck mass which is an ...
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Mass parameters in the spontaneous symmetry breaking

In Ashok: Lectures on Quantum Field Theory Sec. 7.5 p.279 he discusses the mass parameters for the potential $$V = -\frac{m^2}{2}(\sigma^2+\xi^2) + \frac{\lambda}{16}(\sigma^2 + \xi^2)^2.$$ My (...
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Is rest mass determined by the kinetic energy of inner particles?

I haven't studied physics in many years, please forgive my lack of proper formalism. With that being said... The total energy is a function of rest mass energy and the velocity of the object, and is ...
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Is there a need to consider the relativistic mass when calculating gravitational potential energy?

The equation for gravitational potential energy is: $$V(r) ={GMm\over r}$$ In the reference frame where $M$ is stationary. I am wondering for mass $m$ here do we need to consider its relativistic ...
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Is the notion of 'weight of Earth' meaningless?

I am not talking about the distinction between mass and weight, just the concept of 'weight'. In University physics (book by Young & Freedman, 14th Ed.) it is given that the weight of an object ...
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Free fermion Lagrangian invariance under chiral symmetry

I want to apply this transformation to a free-fermion lagrangian: $$L=\bar{\psi}(\gamma^\mu{\partial_\mu \,- m)\,\psi}$$ $$\psi ' =\psi\; e^{i \alpha \gamma_5}$$  \bar{\psi}'=\bar{\psi} \;e^{-i \...
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Magnetic field like phenomenon associated with Gravitational Field [duplicate]

Like in electrodynamics we have magnetic fields associated with electric fields, is there something similar related with gravitational fields too? I mean both are quite similar fields...(Maybe I'm ...
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Does the mass of a beaker filled with water change due to a mass partially submerged in it?

I believe it should be different as there is upthrust acting on the second block and hence by Newton Third's Law it should act back on the liquid adding to more weight. The answer is given isn't so as ...
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Relativistic mass effect

Does relativistic mass phenomena only appear while accelerating or even when the object is travelling at constant velocity (say 90% speed of light)?
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Are conservation of mass and conservation of energy *independent* constraints for physical systems?

I'm modeling fluid systems and want to use conservation of mass (aka 'continuity') and conservation of energy as constraints to help solve for certain system parameters. But it occurred to me that the ...
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Theoretically, if you could attach a 1 meter string with a weight on the end to the exact center of the earth what would it do? [closed]

Would the mass of the weight keep moving towards the center but overshoot and repeat the process?
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Which is more fundamental property of matter: charge or mass? [closed]

I haven't got a whole satisfying answer to this question. I think that matter can exist without charge but it can't exist without mass. Am I correct? So this fact may be answered by asking about the ...
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Meaning of mass-deformation in string theory and quantum field theories

I was reading some papers in the ABJM theory. I keep reading the term mass deformation but am not sure what it really means. I think the papers assume the reader is familiar with the term. Example ...
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Did the Chernobyl power station's water cistern really hold $7000\:\rm m^3$? [closed]

In he HBO TV miniseries Chernobyl, they talk about a cistern holding 7000 cubic meters of water. That is the content of Loch Ness, the deepest lake in the UK. Would the Chernobyl reactor really hold ...
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Why gravitational mass and inertial mass being same was a problem before Einstein solved it?

Why is it so that Einstein is credited with telling us the reason for the equivalence of inertial and gravitational mass of an object? Did Newton ever make a distinction between the two masses? What ...
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Accelerator on a Turntable [closed]

If a circular particle accelerator were placed on a "frictionless" turntable and then turned on, would it spin opposite to the motion of the accelerating particles?
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Force measurement [closed]

We have a bike and a biker on it of mass 81 kg combined. Biker can reach speed around 30k/h. And the question is: how to measure the force (in Newtons) applied on the bike to reach that speed in 10 ...
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How do we define “mass” in the context of particle physics and relativity?

In laypersons terminology, mass is defined as the amount of matter. However, consider the following: The $W$ and $Z$ bosons have mass. An antiparticle has the same mass as its corresponding particle. ...
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What's the simplest way to measure mass without using gravity?

I'm putting together some rough ideas for physical experiment designs and datasets, relating to multiple hypotheses for quantum gravity. Because I'm working on experiments to test theories of gravity,...
Suppose we have a Green's function of the typical form \begin{equation} G(k)=\frac{1}{k^2-m^2-\Sigma(k)} \end{equation} where $\Sigma(k)$ is the self energy of that particle. How exactly can we ...