Home | Contact Us | FAQ | Search & Site Map | Link to Us
Sign In | Join | Other 45 Sites in Network
Home
Discussion Groups
Biology
BiologyBotanyMicrobiologyEntomologyEvolutionPaleontology
Chemistry
General ChemistryAnalytical ChemistryElectrochemistryOrganic Synthesis
Earth Science
GeologyMineralogyOceanographyMeteorologyEarthquakes
Physics
General PhysicsResearchRelativityParticle PhysicsElectromagnetismFusionOpticsAcousticsNew Theories

Natural Science Forum / Physics / General Physics / April 2007



Tip: Looking for answers? Try searching our database.

Precession of Binary Star PSR 1913+16

Thread view: 
Enable EMail Alerts  Start New Thread
Thread rating: 
shalayka@gmail.com - 28 Apr 2007 18:50 GMT
I am wondering if the following method for calculating the
relativistic precession of a highly eccentric orbit has a name, or is
available in some published document?

Using the system parameters found in http://www.johnstonsarchive.net/relativity/binpulsar.html

The orbit radius is taken to be the average of one half of the
separation distances at apastron and periastron:
r = (1576800e3 + 373300e3) / 2.

The average orbit velocity, where M is an average mass of 1.414 solar
masses:
v = sqrt(G*M / r)

The combined orbit circumference is:
C = 2 * (2*pi*r)

The orbit time is:
t = C / v

The precession rate in orbits per orbit, where e is the average orbit
eccentricity (0.617131):
n = 2*pi*(1 - cos(asin(v/c))) / (1 - e*e)

Converted to degrees per Earth year:
d = n * (365/(t/24/60/60)) * 360 = 4.4,

where modern General Relativity provides an approximation of 4.2
degrees per year.

If you are interested, I have put up a short PDF document online,
which includes C++ source code:
http://cavekitty.com/archives/The_Relativistic_Precession_of_Binary_Star_PSR_191
3+16.zip


Thank you for any information that you can provide.
- Shawn
Androcles - 28 Apr 2007 19:09 GMT
>I am wondering if the following method for calculating the
> relativistic precession of a highly eccentric orbit has a name, or is
[quoted text clipped - 9 lines]
> masses:
> v = sqrt(G*M / r)

That is a schoolboy blunder.
A car drives up a hill for one mile taking 2 minutes to get to the top.
How fast must it descend the same distance the other side to have an
average velocity of 60 mph?

I drive from home to London (30 miles for 1 hour), at 80 mph most of
the way (I really do).
What is my average velocity, my maximum velocity and my minimum
velocity?

> The combined orbit circumference is:
> C = 2 * (2*pi*r)

Wrong. What is the circumference of an ellipse?
 http://mathworld.wolfram.com/images/gifs/EllipticGears.gif
shalayka@gmail.com - 28 Apr 2007 21:27 GMT
Hi Androcles,

If I hadn't included eccentricity in the equation, the result would
have been extremely different (and wrong).

However, to perform my due diligence, and appease your objections, I
will work on modifying the equation so that the eccentricity is not
abstracted to the highest level possible as done in my original post
to this thread. I am very familiar with Ramanujan's 2nd method for
approximating the circumference of an ellipse, and use it exclusively
in my other endeavours.

What I am wondering now is if this method works for binary stars of
much different mass (but not so much different that it would simplify
back down to a Sun-Mercury type relationship).

I'm guessing at this point that it will, but that I would have to
average their eccentricities before plugging them into the equation. I
just can't seem to find a lot of information on binaries at this time.

I appreciate your response, because the points you bring up are very
important to note, ex: eccentricity has a major part to play in this
equation.

It might be a little pugnacious of me to say so, but I'm not going to
answer your questions. I have asked my questions due to an honest
dilemma, where it seems that you have not. However, to your credit,
you are officially more communicative than the local university at
which I am a registered student. So, thank you for your time. I do
truly appreciate it.

- Shawn

On Apr 28, 12:09 pm, "Androcles" <Engin...@hogwarts.physics.co.uk>
wrote:
> <shala...@gmail.com> wrote in messagenews:1177782625.497884.294940@n59g2000hsh.googlegroups.com...
> >I am wondering if the following method for calculating the
[quoted text clipped - 26 lines]
> Wrong. What is the circumference of an ellipse?
>  http://mathworld.wolfram.com/images/gifs/EllipticGears.gif
Androcles - 28 Apr 2007 22:53 GMT
> Hi Androcles,
>
[quoted text clipped - 11 lines]
> much different mass (but not so much different that it would simplify
> back down to a Sun-Mercury type relationship).

Show that the advance of longitude of perihelion of Mercury is not
completely satisfied by Newtonian Mechanics.
Show that PSR 1913+16 is binary.

> I'm guessing at this point that it will, but that I would have to
> average their eccentricities before plugging them into the equation. I
> just can't seem to find a lot of information on binaries at this time.

Guessing is what horse race punters do. The bookie sets the odds and
wins every time. Mathematicians do not guess, they prove.

> I appreciate your response, because the points you bring up are very
> important to note, ex: eccentricity has a major part to play in this
> equation.

No circular orbit can show precession.


> It might be a little pugnacious of me to say so, but I'm not going to
> answer your questions. I have asked my questions due to an honest
> dilemma, where it seems that you have not. However, to your credit,
> you are officially more communicative than the local university at
> which I am a registered student. So, thank you for your time. I do
> truly appreciate it.

You can have my time but it goes with my skepticism and incredulity.
I'm almost willing to accept this:
http://antwrp.gsfc.nasa.gov/apod/ap040513.html
is a close orbit eclipsing binary.
I am not willing to accept the forerunner of all binaries is a binary, based
on the word of an 18-year-old kid with a wooden telescope.
http://www.androcles01.pwp.blueyonder.co.uk/Algol/Algol.htm

If you wish to call a star and planet a binary, then Sirius is a star
and planet.
http://antwrp.gsfc.nasa.gov/apod/ap001006.html
After all, it has a 50 year period placing the orbit comparably a bit
futher away than Saturn (29 years) and closer than Uranus (84 years).

You have enough there to keep you going for a few years.
Try not to guess or rely on other people's guesses and maybe you'll
become a real scientist. There are not many of those, but plenty of
pseudo-scientists.

> - Shawn
>
[quoted text clipped - 30 lines]
>> Wrong. What is the circumference of an ellipse?
>>  http://mathworld.wolfram.com/images/gifs/EllipticGears.gif
shalayka@gmail.com - 29 Apr 2007 02:57 GMT
Like I said, I am only guessing because I don't have the data. Call it
a prediction if you like.

As for being a scientist, I'm fine with not fitting the bill. The
methods I'm using are on par with General Relativity, regardless of
what I'm called. In fact, all of the scientists that I've tried to
communicate with have obviously lost the flare that comes with
learning and exploring the world. Otherwise, I would assume that they
would be interested in helping others learn about the universe instead
of berating or ignoring them. I'm sure you can agree that it's
lugubrious to want to associate oneself with that type of person,
regardless of title.

- Shawn

On Apr 28, 3:53 pm, "Androcles" <Engin...@hogwarts.physics.co.uk>
wrote:
> <shala...@gmail.com> wrote in messagenews:1177792048.598466.293320@n59g2000hsh.googlegroups.com...
> > Hi Androcles,
[quoted text clipped - 90 lines]
> >> Wrong. What is the circumference of an ellipse?
> >>  http://mathworld.wolfram.com/images/gifs/EllipticGears.gif
shalayka@gmail.com - 29 Apr 2007 03:09 GMT
I should be more specific here. I am only commenting on the behaviour
of those scientists at the university which I have paid good money
toward. I wouldn't have wasted my time and effort if I had known they
were going to be so completely useless to me in my desire to learn. I
know it's final examinations right now, but taking a month to reply to
an email message is stretching the limits of my good patience -- and
I'm a parent, so please believe me when I say that I have a near-
infinite supply of patience when it's appropriate.

- Shawn

On Apr 28, 7:57 pm, shala...@gmail.com wrote:
> Like I said, I am only guessing because I don't have the data. Call it
> a prediction if you like.
[quoted text clipped - 108 lines]
> > >> Wrong. What is the circumference of an ellipse?
> > >>  http://mathworld.wolfram.com/images/gifs/EllipticGears.gif
Androcles - 29 Apr 2007 08:09 GMT
>I should be more specific here. I am only commenting on the behaviour
> of those scientists at the university which I have paid good money
[quoted text clipped - 4 lines]
> I'm a parent, so please believe me when I say that I have a near-
> infinite supply of patience when it's appropriate.

Under discussion is "Precession of Binary Star PSR 1913+16", not exam time, parenting,
cost of tuition or tardiness of faculty.

I'm not interested in your personal problems of everyday life no matter
how specific you are or what excuses you make, to me they are mere
gossip, and nor can I render you any assistance in resolving them.
Show that the advance of longitude of perihelion of Mercury is not
completely satisfied by Newtonian Mechanics.
Show that PSR 1913+16 is binary.

> On Apr 28, 7:57 pm, shala...@gmail.com wrote:
>> Like I said, I am only guessing because I don't have the data. Call it
[quoted text clipped - 109 lines]
>> > >> Wrong. What is the circumference of an ellipse?
>> > >>  http://mathworld.wolfram.com/images/gifs/EllipticGears.gif
Eric Gisse - 29 Apr 2007 03:21 GMT
On Apr 28, 5:57 pm, shala...@gmail.com wrote:

[...]

Don't listen to Androcles. He is a spewing idiot with delusions of
competence.
Androcles - 29 Apr 2007 07:59 GMT
> Like I said, I am only guessing because I don't have the data. Call it
> a prediction if you like.
[quoted text clipped - 7 lines]
> lugubrious to want to associate oneself with that type of person,
> regardless of title.

I am interested in helping homo sapiens sapiens to think about
Nature as it is, I am not interested in training homo neanderthalensis
to become a shaman pushing buttons on a calculator, dividing by zero
and claiming he's now a mathematician.
GR is on a par with palmistry, reading horoscopes and tea leaves.
Learning about Nature does not mean inventing it.
You choose to be a shaman, attempting to fool others as you succeed
in fooling yourself.
Whether you agree or not, it's idiotic to want to associate oneself with
that type of imbecile, regardless of title. Better to ignore them.
Please go away, start a new newsgroup, "shaman.physics", you are fine
by not fitting the bill, and you don't.

> On Apr 28, 3:53 pm, "Androcles" <Engin...@hogwarts.physics.co.uk>
> wrote:
[quoted text clipped - 92 lines]
>> >> Wrong. What is the circumference of an ellipse?
>> >>  http://mathworld.wolfram.com/images/gifs/EllipticGears.gif
shalayka@gmail.com - 29 Apr 2007 03:01 GMT
P.S. Thank you again for the links. My main desire at the moment is
for actual system data like eccentricity, apastron/periastron
separation distances, and precession estimates/observations. However,
I do find the pictures of these systems on NASA's page to be
fascinating.

On Apr 28, 3:53 pm, "Androcles" <Engin...@hogwarts.physics.co.uk>
wrote:
> <shala...@gmail.com> wrote in messagenews:1177792048.598466.293320@n59g2000hsh.googlegroups.com...
> > Hi Androcles,
[quoted text clipped - 90 lines]
> >> Wrong. What is the circumference of an ellipse?
> >>  http://mathworld.wolfram.com/images/gifs/EllipticGears.gif
Androcles - 29 Apr 2007 08:19 GMT
> P.S. Thank you again for the links. My main desire at the moment is
> for actual system data like eccentricity, apastron/periastron
> separation distances, and precession estimates/observations.

Totally impossible to obtain. Anything you think you have is idle
guesswork.

> However,
> I do find the pictures of these systems on NASA's page to be
> fascinating.

Where your heart line reaches and crosses your life line there'll be a crux
in your life, you'll be at a crossroads.  
 http://www.handanalysis.co.uk/

How fascinating...<yawn>

"That fellow seems to me to possess but one idea, and that is a wrong one."--Dr. Samuel Johnson
"There are well-dressed foolish ideas, just as there are well-dressed fools."--Nicolas Chamfort



> On Apr 28, 3:53 pm, "Androcles" <Engin...@hogwarts.physics.co.uk>
> wrote:
[quoted text clipped - 92 lines]
>> >> Wrong. What is the circumference of an ellipse?
>> >>  http://mathworld.wolfram.com/images/gifs/EllipticGears.gif
shalayka@gmail.com - 30 Apr 2007 19:35 GMT
The precession data is not impossible to obtain. I'm sure there's been
one or two binaries found since 1973.

As for my "problems", they are not personal, they're professional. I
just got a very detailed reply from my university, which means that
they were not ignoring me. I guess that means the problem is theirs,
since they are overworked.

By the way, where did you get the precession data that you used to
verify your methods? Or have you only explained the precession of
Mercury?

- Shawn
Androcles - 30 Apr 2007 20:22 GMT
> The precession data is not impossible to obtain. I'm sure there's been
> one or two binaries found since 1973.

Then do it.
shalayka@gmail.com - 30 Apr 2007 21:43 GMT
Do what? Contact the local universities to see if I can get data on
binary stars? I've already done that.

How do you not get dizzy from the circles you're constantly running
in?

Don't get me wrong, I enjoy reading your posts. However, I'm confident
at this point that you are constructing a fantasy conversation in your
head that has nothing to do with what we're actually talking about.
Not exactly frustrating, just bewildering.

- Shawn

On Apr 30, 1:22 pm, "Androcles" <Engin...@hogwarts.physics.co.uk>
wrote:
> <shala...@gmail.com> wrote in messagenews:1177958128.065520.238070@y80g2000hsf.googlegroups.com...
> > The precession data is not impossible to obtain. I'm sure there's been
> > one or two binaries found since 1973.
>
> Then do it.
Androcles - 01 May 2007 00:20 GMT
> Do what? Contact the local universities to see if I can get data on
> binary stars? I've already done that.

It was you that said it was possible to obtain the data, not I. Run around
in circles until you have it.

> How do you not get dizzy from the circles you're constantly running
> in?

It's your circle. I'm sitting back waiting for you to obtain some data.  <shrug>


> Don't get me wrong, I enjoy reading your posts. However, I'm confident
> at this point that you are constructing a fantasy conversation in your
> head that has nothing to do with what we're actually talking about.
> Not exactly frustrating, just bewildering.

> - Shawn
Are you?

> On Apr 30, 1:22 pm, "Androcles" <Engin...@hogwarts.physics.co.uk>
> wrote:
[quoted text clipped - 3 lines]
>>
>> Then do it.
 
Sign In
Join
My Latest Posts
My Monitored Threads
My Blog
My Photo Gallery
My Profile
My Homepage

Start New Thread
Enable EMail Alerts
Rate this Thread



©2009 Advenet LLC   Privacy Policy - Terms of Use
This website includes both content owned or controlled by Advenet as well as content owned or controlled by third parties.