- #1
Bladibla
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At what mass does an object start to noticeably bend light?
pervect said:The angle through which light is deflected by a massive object depends on both the mass of the object, and how close the light gets to the object.
For small angles, the formula is
[tex]\Theta = \frac{4GM}{bc^2}[/tex]
b is the impact parameter. This can be determined by the "distance" (really, the Schwarzschild r coordinate) at closest approach by the formula
[tex]
b = \frac{r}{\sqrt{1-\frac{2GM}{rc^2}}}
[/tex]
These formulas were taken from MTW, pg 672-4, with the units converted back to standard units from "geometric" units.
Those are the detailed formulas - you'll need to define "noticable" for us to give you a numerical answer.
The relationship between gravity and light is complex and involves the bending of space and time. According to Einstein's theory of general relativity, massive objects such as planets and stars cause a distortion in the fabric of space-time, which can then affect the path of light. This is known as gravitational lensing.
Gravity bends light by warping the fabric of space-time. When light passes near a massive object, the space-time around it is curved, causing the light to follow a curved path. This is similar to how a marble would roll along a curved surface. The more massive the object, the stronger the gravitational pull and the greater the bending of light.
Light cannot escape from a black hole because the gravitational pull is so strong that it pulls everything, including light, towards its center. The boundary around a black hole from which nothing, including light, can escape is called the event horizon. This is why we are unable to see beyond the event horizon of a black hole.
Yes, gravity can affect the speed of light. According to general relativity, the speed of light in a vacuum is always constant. However, when light passes through a region with a strong gravitational field, its speed can appear to be slower or faster depending on the observer's perspective. This is known as gravitational time dilation.
Studying the bending of light by gravity is important because it helps us understand the fundamental principles of the universe and how gravity affects the behavior of light. It also has practical applications, such as in the detection of distant galaxies and the confirmation of Einstein's theories of general relativity. Additionally, studying the bending of light by gravity could lead to new advancements in technology, such as gravitational wave detectors.