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 ...
- 7,661
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 ...
- 80.5k
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) $p^2\not =0$ ($...
- 7,336
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 ...
- 39.8k
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"...
- 31.2k
Only top scored, non community-wiki answers of a minimum length are eligible