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13 votes

If massless objects ALWAYS travel at the speed of light and gluons are massless, how are they trapped within hadrons without a need for event horizon?

That quarks and gluons are trapped inside hadrons is called color confinement. As far as I know: it is unrelated to black holes but I don't read Phys Rev D... it's possible it has been suggested ...
  • 26.9k
10 votes

If massless objects ALWAYS travel at the speed of light and gluons are massless, how are they trapped within hadrons without a need for event horizon?

Now, to make the light trapped within a small region of spacetime, we need curvature so big that it causes an event horizon, so now we have a Black Hole Photons do not carry an electric charge. So ...
10 votes

Why light can't escape a black hole but can escape a star with same mass?

yes, it is because the black hole is much more dense which means it packs the same mass & gravitational pull into a much smaller diameter. This means its surface gravity yields an escape velocity ...
9 votes

What happens to the velocity of a radioactively decaying object?

These two statements are incompatible with each other an ideal box, which perfectly isolates the inside from the outside - no radiation escapes the box and the outer surface of the box does not ...
  • 77.9k
6 votes
Accepted

Do virtual particles have negative mass?

Virtual particles do not fulfill the dispersion relation for a single relativistic particle $p^2\not = m^2$ or if the rest mass of the concerned particle is zero (for instance a photon) $p^2\not =0$ ($...
5 votes

How does most energy get transfered to mass at high relavistic speeds, but mostly to movement at low speeds?

The formula for kinetic energy that applies for a body at all possible speeds (not just speeds much less than the speed of light, $c$) is $$\text{KE}=mc^2\left(\frac 1{\sqrt{1-v^2/c^2}}-1\right)$$ $m$ ...
  • 30.6k
3 votes

Why light can't escape a black hole but can escape a star with same mass?

There are a lot of ways to explain this, with various levels of accuracy. I'm going to choose a way to justify this, in the spirit that the original question seems to not come from a place with a lot ...
3 votes

Why light can't escape a black hole but can escape a star with same mass?

Yes, it's just because the black hole is smaller. The only mass factor relevant to the trajectory of a particle in a spherically symmetric mass distribution is the total mass that is closer to the ...
  • 10.7k
2 votes
Accepted

How do we calculate the mass of a scalar field that represents finite mass?

I think you may be mixing up two concepts. The first concept is the mass of a particle associated with a field. When we say "a scalar field has mass $m$", what we mean is that quanta (...
  • 41.2k
2 votes

What happens to the velocity of a radioactively decaying object?

You have to decide whether you want to model the box or not; on the left of your picture you don't assign it any mass, but on the right it scatters the alpha particles. Momentum conservation holds ...
  • 5,454
2 votes

Do virtual particles have negative mass?

Feynman diagrams conserve energy and momentum at the vertices, so at tree level, the one virtual particle's $q_{\mu}$ is determined by the real external particles. This is where the Mandelstam ...
  • 26.9k
1 vote

How to prove law of mass conservation?

Your edit statement is not valid, since you move the density $\rho$ inside the derivative, indicating you are assuming that the density is constant with respect to t and thus forcing the condition ...
  • 6,018
1 vote
Accepted

Could we derive the mass of neutrinos using a supernova and gravitational lensing?

Not realistically. For a gravitational lens, you obviously need a lensing object such as a galaxy in between you and the supernova. So, we are talking supernovas that are at cosmological distances, ...
  • 5,454
1 vote
Accepted

Why do we use nuclide mass in nuclear reactions instead of nucleus mass?

Mass spectrometry can be used to very accurately find the relative atomic (actually ionic and a correction can then be made) masses compared to a Carbon-$12$ atom. The difference between the atomic ...
  • 83.5k
1 vote

Can we say that the center-of-momentum frame is the frame in which the center of mass is at rest?

Let's check a simple 1D situation: 2 equal mass particles on a collision course. One (1) at rest at the origin, and another (2) moving in the $+$ direction towards it: $$ x_1m = 0$$ $$ x_2(t)m = (x_2(...
  • 26.9k
1 vote

Can we say that the center-of-momentum frame is the frame in which the center of mass is at rest?

In newtonian mechanics, center-of-momentum frame is the same as the frame in which the center-of-mass is at rest as showed in your derivation.
  • 174
1 vote

Remote mass detection and location

Your accelerometers would be measuring acoustic waves from the airplanes and the phenomena. There is already a global array of infrasound detectors and seismometers to monitor for nuclear tests, and ...
  • 5,394
1 vote

If mass and energy can neither be created nor be destroyed then how in nuclear fusion mass is converted to energy with the formula $E = mc^2$

"Mass is converted to energy" is a widespread but sloppy and misleading expression. Mass is a different concept than energy and there is no conversion. More correctly, "mass energy"...

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