No, the photons would gravitate more due to their pressure.would massless photons and an equivalent number of mass-energy atoms have the same effects on gravity?
Neither do. You need the full http://en.wikipedia.org/wiki/Stress-energy_tensor" as a source term.Does mass play any special role in gravity or only energy?
A photon is a fundamental particle of light and electromagnetic radiation. It has no mass or charge, and travels at the speed of light.
Photons and atoms are related because photons are the basic building blocks of light and atoms are made up of particles called protons, neutrons, and electrons, which are affected by light and electromagnetic radiation.
Yes, photons can be affected by gravity. According to Einstein's theory of general relativity, gravity is the curvature of space and time caused by massive objects. Since photons have energy, they can be affected by this curvature.
Photons and atoms interact with gravity through the force of gravity. This force is a result of the curvature of space and time caused by massive objects. Both photons and atoms are affected by this curvature and can be pulled towards massive objects.
The number of photons and atoms is not equivalent in terms of gravity. While both are affected by gravity, the strength of the gravitational force on a photon is much weaker compared to an atom due to the difference in their masses. Additionally, photons do not have a gravitational charge, while atoms do.