## Spacetime curvature

at the center of a planet/star/etc

Study matter and its motion through spacetime...

### Re: Spacetime curvature

hackenslash

Name: The Other Sweary One
Posts: 21437
Age: 50

Country: Republic of Mancunia
Print view this post

### Re: Spacetime curvature

How is he making a hyperbola with only one point? How does he know the shape of the hyperbola with just one point? And I still don't get why a hyperbola and why it goes away from the centre?
A most evolved electron.

Animavore

Name: The Scribbler
Posts: 43213
Age: 41

Print view this post

### Re: Spacetime curvature

Animavore wrote:How is he making a hyperbola with only one point? How does he know the shape of the hyperbola with just one point? And I still don't get why a hyperbola and why it goes away from the centre?

ETA Not referring to the video here, just to the hyperbola that appears in special relativity:

Using t for time and x for space, take t2 - x2 = 1 for example

rewrite as t2 = 1 + x2

rewrite again as t = sqrt(1 + x2)

Let's just take positive square roots for now:

if x = 0, shoving it in that last equation gives t = 1
Letting x start to go positive, say x = 0.0001, gives t just a titchy bit greater than 1, and as x increases t goes even greater than one. It never gets closer. Letting x go negative, say x = -0.0001, ALSO gives t just a titchy bit greater than 1, since x gets squared, in the formula, so again as x goes negative t increases and stays greater than 1.

So 1 is the smallest t ever gets, and you get the hyperbola-in-the-top-half shape.

But of course when you take the square root of a number, you can take the negative square root as well as the positive one, so the hyperbola in the top half gets mirrored in the bottom half.
A soul in tension that's learning to fly
Condition grounded but determined to try
Can't keep my eyes from the circling skies
Tongue-tied and twisted just an earthbound misfit, I

twistor59
RS Donator

Posts: 4966

Print view this post

### Re: Spacetime curvature

So you're using 't' for 'y' here?
That makes sense.
A most evolved electron.

Animavore

Name: The Scribbler
Posts: 43213
Age: 41

Print view this post

### Re: Spacetime curvature

Animavore wrote:So you're using 't' for 'y' here?
That makes sense.

Yeah.

In relativity, a common convention is that you give the t2 term the positive sign and x2, y2, and z2 the negative signs when you're constructing the hyperbolas
A soul in tension that's learning to fly
Condition grounded but determined to try
Can't keep my eyes from the circling skies
Tongue-tied and twisted just an earthbound misfit, I

twistor59
RS Donator

Posts: 4966

Print view this post

### Re: Spacetime curvature

Ok. I just want to make sure I have this right before I move on (or even read the chapter again).

As per the equation above the line of the hyperbola can be seen as an infinite series of points depending on the value of x, correct?

and;

Each of those points represents a distance from the event with none of the observers on any point, obviously seeing the event before it happens, or do the points represent people at different speeds or is it either?
A most evolved electron.

Animavore

Name: The Scribbler
Posts: 43213
Age: 41

Print view this post

### Re: Spacetime curvature

A) Correct.

B) The former. The hyperbola represents a continuum of all the points at which the distance in spacetime between event O and event A is equal to s, as per the diagram in this post.

hackenslash

Name: The Other Sweary One
Posts: 21437
Age: 50

Country: Republic of Mancunia
Print view this post

### Re: Spacetime curvature

Yes, for the example I gave, the distance, s, in hack's post, was equal to 1. So the hyperbola is the set of all events with "distance" 1 from the orgin. In Hack's the distance was a generic number, s.
A soul in tension that's learning to fly
Condition grounded but determined to try
Can't keep my eyes from the circling skies
Tongue-tied and twisted just an earthbound misfit, I

twistor59
RS Donator

Posts: 4966

Print view this post

### Re: Spacetime curvature

A most evolved electron.

Animavore

Name: The Scribbler
Posts: 43213
Age: 41

Print view this post

### Re: Spacetime curvature

Here's a very recent lecture from Brian Cox filmed by an amateur. You might need to turn it.

A most evolved electron.

Animavore

Name: The Scribbler
Posts: 43213
Age: 41

Print view this post

### Re: Spacetime curvature

OK, so I turned it, but that just meant that I couldn't read the captions...

hackenslash

Name: The Other Sweary One
Posts: 21437
Age: 50

Country: Republic of Mancunia
Print view this post

### Re: Spacetime curvature

*up*
A most evolved electron.

Animavore

Name: The Scribbler
Posts: 43213
Age: 41

Print view this post

### Re: Spacetime curvature

Watched that lecture now. Excellent stuff.

hackenslash

Name: The Other Sweary One
Posts: 21437
Age: 50

Country: Republic of Mancunia
Print view this post

### Re: Spacetime curvature

Spacetime???

EOTOE, Some Implications (2)

This equation describes the presently expanding universe:

E=Total[m(1 + D)] D = distance travelled by mass since singularity

This equation describes the future contracting universe:

E=Total[m(1 - D)] D = distance travelled by mass since end of expansion

Implications:

The base units of mass - may be designated gravitons but MUST have mass - are not temporal,
they never disappear.

In the present expanding universe they are in motion as mD away from the singularity point.
Those of them that hit a whatever mass format and move it become inert. This will go on until
all or nearly all of them cease moving forward, i.e. until D ceases growing.

When D ceases growing gravitation will overcome the inertial motion away from the singularity
point and will start pulling them back towards it. It is then that -D will replace +D , to maintain
the equation’s equality…

And MORE, MUCH MORE:

The rational commonsensical, and therefore scientifically probable, implication is that Space is
Imbued with these massed gravitons that are continuously left behind during Expansion…

Dov Henis (comments from 22nd century)
http://universe-life.com/
http://universe-life.com/2011/10/07/eot ... cations-i/

Dov Henis
Banned Spammer

Name: Dov Henis
Posts: 16

Country: Israel
Print view this post

Previous