Questions tagged [gravity]
Gravity is an attractive force that affects and is affected by all mass and - in general relativity - energy, pressure, and stress. Prefer newtonian-gravity or general-relativity if sensible.
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Gravitational halos made of neutrinos
I have been recently interested in how halos made of standard model particles could be formed and behave.
After asking some questions in this site, I was told about how neutrinos could form such halos....
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What is the energy density of gravitational fields around neutron stars? [closed]
The field strength of gravitational fields around neutron stars is extremely high. This would lead to an extreme negative value for the energy density. But if an absolute negative energy density is ...
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How to properly combine kinetic and gravitational time dilation effect?
I developed a time dilation calculator that includes both kinetic (Lorentz Factor) and gravitational (Schwarzschild Metric Formula) factors to assess the time difference between Earth and satellites. ...
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Do you always experience the gravitational influence of other mass as you see them in your frame?
You see a galaxy far away. That galaxy is attracting you with a certain amount of gravity. I'm wondering if the gravity influence of the galaxy on you, as measured by you, always ends up being what ...
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How much time does it take for an object to fall from space? [closed]
Let's say there's an object of mass $m$ in space, $h$ meters away from the surface of the Earth. $h$ is large enough that $g$ cannot be assumed to be constant. The acceleration varies according to ...
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Tug of war between observers in frames with different rate of time
You have a very dense hollow sphere of matter. Observer A is inside the sphere inside a rocket. Observer B is in an identical rocket outside the sphere where the ring's gravity is negligible. They are ...
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Do clocks tick faster when gravitational forces are weaker?
A professor last year taught us that "gravity slows clocks," when teaching about the relationship between gravity and time. This led me to think about places, such as intergalactic space, ...
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Does Matter Cause Curvature or Vice-Versa [closed]
From the way explanations about gravity-acceleration-curvature equivalence are usually phrased here or elsewhere, it would appear many or most think that matter causes space-time curvature.
I cannot ...
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Binary black hole merging condition
Assuming two black holes with the same rest mass $m$ collid coming from infinity with velocity $v$ and impact parameter $b$. Lets ignore spin at first. For which values of $v$ and $b$ would these ...
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How significant is the parabolic arch effected with an incline versus a decline in angle versus a decline in angle . For example throwing a dart
A dart players height can vary as can the height in which they raise their arm to aim.
Is there less parabolic arch when throwing at the same strength from above the target compared to below, due to ...
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Bound states between neutrinos using Schrödinger's equation?
I would like to see if it's possible that neutrinos (with sufficiently slow velocities) could form bound states in a universe with matter (such as ours)
There is a cosmic neutrino background in the ...
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Second-order equations of motion for higher derivative gravity?
We know that Lovelock gravity is the most general theory of gravity possible for Lagrangians which depend only on the metric tensor and the Riemann tensor
\begin{equation*}
L = L \left(g_{\alpha\beta},...
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Better equations for modeling and simulating a halo orbit?
I'm trying to model a halo orbit at low altitude (10m from surface). The satellite is using propulsion to trace the circular halo path. It looks like this "from the top" (the blue ball is ...
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Minimum energy to lift state of Utah one mile over 5-10 million years?
The following seems an elementary geophysics query, but I’m not sure
how to do a direct calculation. My geology text mentions that over the
past 5 to 10 million years, the state of Utah and some ...
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Does gravitational redshift conserve energy?
It is claimed that redshift due to cosmological expansion doesn't conserve energy. Does this exception also apply to gravitational redshift? Why or why not?
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