Can anybody Shed some "light" on this for me

B

Beaz

Temporal Novice
Can anybody Shed some \"light\" on this for me

Hello,

I have just joined this site in search of an answer, i hope you might be able to shed some "LIGHT" for me..

OK. Acording to good old Albert, things moving move slower through time.. as you approch the speed of light, time slows down and as you suppass the speed off light time reverse's "maybe"
So at some point time stops going one way and goes the other which makes me thing at some point time doesnt move atal. I would guess that this is when the light barrier is reached 160.000 MP/s or whatever it is.. I've also heard that matter moving at this speep becomes energy "light"
Would this mean that all light and all matter that has reached that speed is now out side of time or frozen in time waiting to slow down or speed up..
I have a hard time getting my head around all this.. is all light really timeless.. ???

Thanks

Dean Davies aka "BEAZ"
[email protected]

PS, Please excuse my poor poor spelling ha ha ha
 
Re: Can anybody Shed some \"light\" on this for me

If time is considered a locality within a sphere, then effects placed upon this sphere would affect time placed within that sphere, wouldn't it?
 
Re: Can anybody Shed some \"light\" on this for me

I'm thinking this.

If the spacetime continuum is a closed geodesic (i.e., no multiversal paths for energy/mass to divert onto), then, as light proceeds along a path in a "straight" line, gravity bends the light as it goes along. Even in a vast geodesic (accepting the span of the geodesic as the currently accepted distance of 4 x 10^26 m), the light would, in effect, CATCH UP TO ITSELF in about 9.3 TRILLION years. I know, it's a long time to wait, but since it would be theoretically happening all the time, we'd be able to observe it. And, in my opinion, what we'd observe is light APPEARING to STAND STILL.
 
Re: Can anybody Shed some \"light\" on this for me

Post relayed in-part, in-case some rovers, do not have web access?

Copy goes> http://preprints.cern.ch/hep-th/hypertext/9511136/node13.html
Timelike and Lightlike Shells in a Spherically-Symmetric Spacetime
In this appendix we derive the matching relations which has to be fulfilled when two ingoing lightlike shells merge into a single timelike shell. We only consider the case of concentric spherical shells that move radially. The three spacetime domains bounded by the shells are static and spherically symmetric with line elements of the following form

We call A, B, C the three spacetimes, , the lightlike shells and the timelike shell [See Fig.5].

Before deriving the matching relation at the intersection let us recall the main equations describing timelike and lightlike shells (for more details see [16]).

We call the normalized 4-velocity and n the unit normal along the timelike surface . With the line element (A.1) the components of these vectors are

with , and . The induced metric of is equal to

A spherically symmetric timelike shell is a 2-dimensional perfect fluid with surface energy and surface pressure p. Let us call the area and the internal mass. Spherical symmetry reduces the number of independent equations describing the motion of the shell to the following two :


Here is the stress-energy tensor of the external medium and the square bracket represents the jump of the enclosed quantity across the surface, i.e. . It is assumed that the normal n is directed toward the + side.

Eq.(A.5) is the equation of motion of the shell and Eq.(A.6) the equation of conservation of energy. To specify the problem one needs also to give an equation of state. If, for instance, one takes with and if one gets from (A.6)



This relation allows one to define which enters Eq. (A.5).

The description of a null shell is very different from a timelike one and in some sense simpler because the equation of motion is fixed. What makes a null hypersurface so peculiar is that its normal vector is at the same time tangent to it and that its induced metric is degenerate.

Let us call with i = 1,2 the two ingoing null shells. The basis vectors where are tangent to the shells and one takes as the null vector tangent to the null generators of . Here whenever r increases (decreases) toward the future along the null generators. As is tangent to , the ``extrinsic'' curvature defined by

where is the 4-dimensional covariant derivative, an intrinsic property of the shell which actually describes the behavior of its null generators. For instance, the trace represents their expansion rate and is equal to

Finally when no energy is transferred to the shell, i.e. , the surface stress-energy tensor of a spherical null shell is characterized only by a surface energy density , which is given by







Let us now find the matching relations at the intersection of the shells. This intersection is in fact a 2-sphere S with radius and at any point of S we can write the following decompositions






where and are arbitrary positive scalars. Furthermore the 4-vectors form a basis at any point of S and we have the completeness relation



In order to get the matching relation we use the fact that are intrinsic quantities and express the product in two different manners using the spacetime domains A, B and C. First using (A.2), (A.3), (A.9) and (A.12) one gets



Second using (A.9) and (A.14) in sector C one gets



One then immediately derives the matching relation



This equation gives the initial velocity of the timelike shell after the merging of the lightlike shells. When this result is inserted in (A.5) one gets the initial mass of the timelike shell.
 
Back
Top