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As mentioned in tfb's answer, the deflection using special relativity to give an "effective mass" is half that of general relativity. In this treatment, the effect is Newtonian (a "gravitational force" interacting directly and instantaneously between two masses). Consider a single photon passing a body of mass M at a distance r. The Newtonian deflection angle is: $$\theta= \frac{2GM}{rc^2}$$

In general relativity, the deflection angle is: $$\theta= \frac{4GM}{rc^2}$$ This is because, in effect, while special relativity considers the warpage of time, general relativity considers spacetime warpage.

One interesting feature to point out is that in the Newtonian approach, the passing object will experience an increase in speed (potential energy converted into kinetic energy). However, according to relativity, a photon cannot be accelerated past c. Instead, the transfer of this energy causes the photon's frequency to increase as it passes through a gravitational well (and decrease upon escaping); this is the phenomenon of gravitational redshift. The energy of a photon is given by $e=h\nu$, where h is Planck's constant, and $\nu$ is the frequency, thus it can be seen that energy and frequency are directly proportional with Planck's constant as the constant of proportionality.

As mentioned in tfb's answer, the deflection treating photons with an "effective mass" is half that of general relativity. While photons have zero rest mass in special relativity, one can consider them with infinitesimal mass for the purposes of a Newtonian approximation (a "gravitational force" interacting directly and instantaneously between two masses). Consider a single photon passing a body of mass M at a distance r. The Newtonian deflection angle is: $$\theta= \frac{2GM}{rc^2}$$

In general relativity, the deflection angle is: $$\theta= \frac{4GM}{rc^2}$$ This is because general relativity considers spacetime warpage.

One interesting feature to point out is that in the Newtonian approach, the passing object will experience an increase in speed (potential energy converted into kinetic energy). However, according to relativity, a photon cannot be accelerated past c. Instead, the transfer of this energy causes the photon's frequency to increase as it passes through a gravitational well (and decrease upon escaping); this is the phenomenon of gravitational redshift. The energy of a photon is given by $e=h\nu$, where h is Planck's constant, and $\nu$ is the frequency, thus it can be seen that energy and frequency are directly proportional with Planck's constant as the constant of proportionality.

As mentioned in tfb's answer, the deflection in special relativity is half that of general relativity. In the special relativity treatment, the effect is Newtonian (a "gravitational force" interacting directly and instantaneously between two masses). Consider a single photon passing a body of mass M at a distance r. The Newtonian deflection angle is: $$\theta= \frac{2GM}{rc^2}$$

In general relativity, the deflection angle is: $$\theta= \frac{4GM}{rc^2}$$ This is because, in effect, while special relativity considers the warpage of time, general relativity considers spacetime warpage.

One interesting feature to point out is that in the Newtonian approach, the passing object will experience an increase in speed (potential energy converted into kinetic energy). However, according to relativity, a photon cannot be accelerated past c. Instead, the transfer of this energy causes the photon's frequency to increase as it passes through a gravitational well (and decrease upon escaping); this is the phenomenon of gravitational redshift. The energy of a photon is given by $e=h\nu$, where h is Planck's constant, and $\nu$ is the frequency, thus it can be seen that energy and frequency are directly proportional with Planck's constant as the constant of proportionality.

As mentioned in tfb's answer, the deflection using special relativity to give an "effective mass" is half that of general relativity. In this treatment, the effect is Newtonian (a "gravitational force" interacting directly and instantaneously between two masses). Consider a single photon passing a body of mass M at a distance r. The Newtonian deflection angle is: $$\theta= \frac{2GM}{rc^2}$$

In general relativity, the deflection angle is: $$\theta= \frac{4GM}{rc^2}$$ This is because, in effect, while special relativity considers the warpage of time, general relativity considers spacetime warpage.

One interesting feature to point out is that in the Newtonian approach, the passing object will experience an increase in speed (potential energy converted into kinetic energy). However, according to relativity, a photon cannot be accelerated past c. Instead, the transfer of this energy causes the photon's frequency to increase as it passes through a gravitational well (and decrease upon escaping); this is the phenomenon of gravitational redshift. The energy of a photon is given by $e=h\nu$, where h is Planck's constant, and $\nu$ is the frequency, thus it can be seen that energy and frequency are directly proportional with Planck's constant as the constant of proportionality.

As mentioned in tfb's answer, the deflection in special relativity is half that of general relativity. In the special relativity treatment, the effect is Newtonian (a "gravitational force" interacting directly and instantaneously between two masses). Consider a single photon passing a body of mass M at a distance r. The Newtonian deflection angle is: $$\theta= \frac{2GM}{rc^2}$$

In general relativity, the deflection angle is: $$\theta= \frac{4GM}{rc^2}$$. This is because, in effect, while special relativity considers the warpage of time, general relativity considers spacetime warpage.

One interesting feature to point out is that in the Newtonian approach, the passing object will experience an increase in speed (potential energy converted into kinetic energy). However, according to relativity, a photon cannot be accelerated past c. Instead, the transfer of this energy causes the photon's frequency to increase as it passes through a gravitational well (and decrease upon escaping); this is the phenomenon of gravitational redshift. The energy of a photon is given by $e=h\nu$, where h is Planck's constant, and $\nu$ is the frequency, thus it can be seen that energy and frequency are directly proportional to Planck's constant.

As mentioned in tfb's answer, the deflection in special relativity is half that of general relativity. In the special relativity treatment, the effect is Newtonian (a "gravitational force" interacting directly and instantaneously between two masses). Consider a single photon passing a body of mass M at a distance r. The Newtonian deflection angle is: $$\theta= \frac{2GM}{rc^2}$$

In general relativity, the deflection angle is: $$\theta= \frac{4GM}{rc^2}$$ This is because, in effect, while special relativity considers the warpage of time, general relativity considers spacetime warpage.

One interesting feature to point out is that in the Newtonian approach, the passing object will experience an increase in speed (potential energy converted into kinetic energy). However, according to relativity, a photon cannot be accelerated past c. Instead, the transfer of this energy causes the photon's frequency to increase as it passes through a gravitational well (and decrease upon escaping); this is the phenomenon of gravitational redshift. The energy of a photon is given by $e=h\nu$, where h is Planck's constant, and $\nu$ is the frequency, thus it can be seen that energy and frequency are directly proportional with Planck's constant as the constant of proportionality.