multibody gravity question

I was picking terminological nits:

"The gravitational intensity I is defined as the force experienced by a unit mass when placed in the gravitational field of another mass M."

You represent that as local horizontal slope at a point on your curves.

"The gravitational potential V at a point in the gravitational field is defined as the work done in taking a unit mass from that point to infinity against the force of gravitational attraction."

That you represent as the height of a given point on a curve above y = 0.

(The work done taking a unit mass from one point to another is the difference in height of two points on a curve.)

The potential can be different but the intensity the same (zero), just as in electrical circuits as I mentioned elsewhere.

Your diagrams seem to feature singularities, which I find distracting.

Have you seen this?

Notice that the top of each "peak" between wells is locally flat, IOW field intensity = force on a particle placed there = zero, same as at the bottom of each well despite them all being at different depths.

This diagram includes the exaggerated curvature of the universe:

Visualizing that to be a patch of the surface of an inflating balloon (2D analog of 3D spacetime) explains dark energy. I think.

Mark L. Fergerson

field intensity = force on a particle placed there = zero, same as at t he bottom of each well despite them all being at different depths.

Well, of course the planets aren't arranged in a straight line like that, e ven if they were stationary, and the plot ignores angular momentum, which i s what keeps everything from falling into the Sun.

BTW I just finished reading that book Martin suggested, "Celestial Encounte rs". It's an interesting read for the mathematically inclined. It has no ac tual math at all, but it helps to know a bit about Cantor sets and measure theory in order to get the gist of how interacting orbits become chaotic. F ive bucks including shipping from ABEbooks.

Cheers

Phil Hobbs

Phil Hobbs

to infinity against the force of gravitational attraction."

same as at the bottom of each well despite them all being at different depths.

Hi,

Thanks nice comic. I was using gravitational field instead of potential since gravitational potential makes it sound more that it is a effect of mass achieving escape velocity, but as you say considering gravitational fields acting on space time instead of just on matter could explain dark energy. It makes sense that gravitational field induced shapes in spacetime would tend to want to find their lowest energy state, which would be to stretch out the ripples, and the curvature from matter in spacetime is one of those ripples (on local scales small ripples, and on universe size scale much higher amplitude ripple that should have a correspondingly larger force towards equilibrium reducing the ripples (dark energy).

cheers, Jamie

another mass M."

point to infinity against the force of gravitational attraction."

same as at the bottom of each well despite them all being at different depths.

Hi,

I think this type of situation could be described by expanding space-time possibly, where a galaxy core has faster space-time expansion than its perimeter.

"huge molecular outflows from deep inside the galaxy's core"

Other explanations being blackhole's and/or stars pushing matter away from the center of the galaxy.

cheers, Jamie

Jamie,

You can't just type in this random word salad with no mathematical foundations. Before you can say anything that makes the remotest sense in this field you have to at least have read and understood Misner, Thorne & Wheelers classic book "Gravitation" which details current knowledge about general relativity upto the 1980's and is heavy enough to disturb the local gravitational field. There is new stuff since then but without good foundations anything you build falls down instantly.

Frantic handwaving with no mathematical or even rational foundations based on random use of buzzwords simply doesn't hack it.

Hi,

Well before math can be used the initial properties of a system need to be known, math has been used already extensively and has not solved dark energy, which indicates a fundamental missing premise!

The two premises I am putting forward is that gravitational curvature is not just a mathematical property but is a real property of space time that exists, and the other premise is that a standing wave of space time curvature will have a equilibrium force which causes it to expand into surrounding space time as a standing wave is higher energy than surrounding space time.. It is the same idea as the surface of water being flat, the only standing wave that is stable on the surface of water is if there are waves travelling in multiple directions, but if a single standing wave, ie a parabolic shape is put into water, ie by lifting a water filled cup upside down out of the water until the cup lets the water splash back down, the water will return to a flat state soon after.

If a slightly gelatinous or higher viscosity mix of water with some other ingredient is dropped into the water the same way, if it floats, it will maintain its parabolic shape and disperse slower.

Matter is like a glue for spacetime in that sense, it is holding space time in a standing wave parabolic shape, but if space time rate of expansion increases that indicates that the glue force provided by matter is less than the dispersion force towards equilibrium (flat) spacetime.

It is the same idea whether physics terms or analogous terms are used when describing it! :)

cheers, Jamie