Gravity is the curvature of space by mass, according to the general theory of relativity. Photons follow the curvature of space along a path called a geodesic, which is the shortest possible line between points on a curved surface.

Gravity is the curvature of space by mass, according to the general theory of relativity. Photons follow the curvature of space along a path called a geodesic, which is the shortest possible line between points on a curved surface.

I have recently asked question difference in weight of photons of different colour at research gate ,but nobody has answered

Hello Professor Adam B Shapiro ! Thanks for the exact answer. I have also read about this curvature that the futons follow. Yet gravity only affects the particles that have mass. At least that's all the theories about the gravitational field. Kind regards! Anton

Hello Professor Satish Narula ! Thanks for the exact answer. Your question is also very curious. I'll follow up for answers and your question too. Yet gravity only affects the particles that have mass. At least that's all the theories about the gravitational field. Kind regards! Anton

Hi Anton. The energy of the photon depends on the frequency. According to the special relativity theory, E = mc ^ 2, which can be interpreted as meaning that the energy is equivalent to the corresponding mass, and that the gravitational field, eg from the star, interact with this mass.

And the question about whether the photon interacts with the another photon will answer the quote from J. Vijayan, RG,: taken from the RG (Jun 21, 2014): "What happens if two photons hit each other?

Ah, this is a very interesting question. On one hand you have classical electrodynamics which says that electromagnetic waves pass through each other without any interference and quantum electrodynamics which says that photons cannot couple directly to each other since they don't carry charge, and on the other hand there are processes like pair production in which photons interact to produce matter (and anti-matter)." Kind regardz! Jerzy

photon is quanta of energy and the energy (E = mc ^ 2) that means the energy is equivalent to the corresponding mass, and that the gravitational field .

Hello Professor Jerzy Hanckowiak Thank you for the extremely competent and comprehensive response. We all know that the energy of the photons depends on the frequency (or wavelength). It is also known that according to the special theory of relativity, E = mc ^ 2. But I am not entirely convinced that it can be interpreted that energy is equivalent to the mass. Interesting is also the topic "What happens if two photons hit one another? :) If the funnel does not really have a mass, the collision between two massless objects seems impossible. Then, the gravitational attraction between 2 futons also seems impossible. Since the photons have no charge - they can not interact as charged particles as well. And the topic about matter and antimatter is another very, very interesting topic that still seems to me fantastic With respect Anton

Hello Professor Hesham Yousef, Thanks for the exact answer.

Kind regards! Anton

I think this short message is interesting:

If photons of light have no mass, how can space be bent by gravity?

by Jonathan O'Callaghan, 26 December 2013

Why does light appear to curve in the universe?

We have seen from observations of light coming from behind objects of high mass, that the light is ‘lensed’ by the gravitational field of massive objects. However, light itself has no mass, so how is it affected by the gravity of these objects?

The first point to make is that while photons (little packets of light energy) do not have mass, they do have momentum, and a change in momentum yields a force, so in actual fact light is able to physically interact with matter. However, the key to this question came when Einstein developed his theory of general relativity. Photons of light are not technically affected by large gravitational fields; instead space and time become distorted around incredibly massive objects and the light simply follows this distorted curvature of space.

Answered by Sophie Allan from the National Space Centre

Image credit ESA, Hubble and NASA

https://www.spaceanswers.com/space-exploration/how-many-spacecraft-have-been-to-venus/

"Photons of light are not technically affected by large gravitational fields;"

is this statement well justified in the context of the deflection of the rays by the sun?

Anton Georgiev : Why photons that have no mass are affected by gravity?

Jerzy Hanckowiak : "Photons of light are not technically affected by large gravitational fields" is this statement well justified in the context of the deflection of the rays by the sun?

Jonathan O'Callaghan is correct: photons are not affected.

In fact neither photons nor particles in space are affected by gravity: All of them are just continuing the motion they previously had, according to Newton's first law. They do not suffer any forces, even though they might be close to a gravitational field, since they are just following geodesics, which we interpret as a "fall" because it is us who are accelerating:

In fact, when a person or object is in contact with the surface of a massive body, such as the Earth, it is the person or object which undergoes a gravitational acceleration, which is sensed by us as a force (our weight). The effect is identical to a spaceship which is accelerating us; if in such situation we release an object, such as a pen, we are going to see it "accelerating", passing us, although it is not the pen that is accelerating, but us. The same occurs with the photons.

Thanks professor Jerzy Hanckowiak, A good example of the paradox "photon gravity"

Thanks professor Diego Saa, Thanks for the competent opinion. I think your explanation is sufficiently logical and comprehensive. It almost exactly coincides with mine. But then there is no explanation of the distortion of light, under the influence of massive "black holes."

Kind regards!

Anton

Hi Diego: "In fact neither photons nor particles in space are affected by gravity: All of them are just continuing the motion they previously had, according to Newton's first law. " The first Newton's law, or actually Galileo's, says that in the inertial system, when no force is acting on the body, etc... What we are talking about is the generalization of this law by Einstein, who, probably under the influence of Maxwell's ingenious works , which unifyed magnetic fields with electric fields, did the same with forces of inertia and gravity?

Professor Jerzy Hanckowiak, Thanks for the competent opinion. I think your explanation is sufficiently logical and comprehensive. Yet, as if this theory did not explain the appearance of "double images" as a result of the distortion of light, under the influence of massive "black holes." If photons "simply continue their movement in space" and they do not distort their trajectory, there would be no mirror images around the gravitational giants.

Anton Georgiev wrote: If photons "simply continue their movement in space" and they do not distort their trajectory, there would be no mirror images around the gravitational giants.

Your both premises are correct. However, we have to interpret what a "non-distorted trajectory" (geodesic) means. Within a gravitational field it does not mean a straight line.

Shapiro already explained: "Gravity is the curvature of space by mass...Photons follow the curvature of space." And also Sophie Allan wrote: "space and time become distorted around… massive objects and the light simply follows this distorted curvature of space."