Gravitational Lensing Deflection angle

• Jrod99
In summary, there was a conversation about finding a derivation of the deflection angle in gravitational lensing. A website was recommended for further information and it was mentioned that there are differences in calculations regarding factors such as central pressure in the Sun.
Jrod99
Does anyone know where I could find (online) a derivation of the deflection angle in gravitational lensing:

alpha = 4GM/Rc^2

Thank you

Hi Jrod
Deflection angle by E=hf (Planck) and so: m=hf/c^2? Restmass of photons=0 but dynamical could be different? What could we ever learn more from Einstein than this? In my lecture about the nonexistance of stellar black holes I come to half of your value, but about factor two-faillures in astrodynamics a whole book could be written. (I myself have two recommended books about astrodynamics witch differ factor two in central pressure in the Sun!). Cosmical lensing is what you want to discuss about isn't it.
greatings Jm

Jrod99 said:
Does anyone know where I could find (online) a derivation of the deflection angle in gravitational lensing:

alpha = 4GM/Rc^2

Thank you

You might find this web page of use-

http://www.mathpages.com/rr/s6-03/6-03.htm

What is gravitational lensing deflection angle?

Gravitational lensing deflection angle is the angle by which light from a distant object is bent as it passes near a massive object, such as a galaxy or black hole, due to the distortion of space-time caused by the object's gravitational field.

How does gravitational lensing deflection angle occur?

Gravitational lensing deflection angle occurs due to the bending of space-time by massive objects, as described by Einstein's theory of general relativity. The mass of the object causes a curvature in space-time, which in turn alters the path of light passing near it.

Why is gravitational lensing deflection angle important?

Gravitational lensing deflection angle is important because it allows us to study and observe objects that may otherwise be too distant or faint to see. It also provides evidence for the presence of massive objects, such as dark matter, in the universe.

What are the different types of gravitational lensing deflection angle?

There are three types of gravitational lensing deflection angle: strong, weak, and microlensing. Strong lensing is caused by highly massive objects and produces multiple images of the background object. Weak lensing is caused by less massive objects and produces subtle distortions in the shape of the background object. Microlensing occurs when a small object, such as a star, acts as a lens.

Can gravitational lensing deflection angle be used to study the properties of the universe?

Yes, gravitational lensing deflection angle can be used to study the distribution of mass in the universe, including the presence of dark matter. It can also provide information about the expansion of the universe and the nature of dark energy. Additionally, it allows us to study the properties of distant galaxies and gain a better understanding of their formation and evolution.

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