Re: [Phys-L] Fwd: [PTSOS] spacetime simulator: flexible conduit?

[Bernard Cleyet <bernardcleyet@redshift.com>]

I'll chime in here.   I thought I and, more correctly, JD had made it clear.  The trampoline models an inverse attractive force rather well, à la, Newton. It does not model space time or more specifically geodesics.  JD specifically wrote (paraphrase)  It's a good demo, BUT not of General Relativity.


bc


On 2012, Jul 19, , at 09:50, William Maddox wrote:

> From: WC Maddox
>
> Message from Southverse where a green LED turns yellow when cooled by LN
> rather than a yellow LED turning green.
>
> 1.      If I want to model a force, rather than potential, that decreases
> with distance I would prefer to use the flexible trampoline type device. The
> slope of the surface decreases with distance from a large mass in the
> center. This device also has the advantage, as shown later in the video,
> that you could pull the material up to demonstrate a repulsive force.
>
> 2.      I suspect the dart and tape model would be more confusing than
> helpful here. How would a repulsive effect, like the part of the
> cosmological expansion that is attributed to some type of "dark energy", be
> modeled using darts and tape? Consider both effect decreases in strength
> with distance and effect increases in strength with distance cases.
>
> End Message
>
>
>
> _______________________________________________
> Forum for Physics Educators
> Phys-l@mail.phys-l.org
> http://www.phys-l.org/mailman/listinfo/phys-l