<p>General relativity makes no distinction between &quot;mass&quot; and &quot;energy&quot;.  Mass is just one form of energy, a form that happens to be intrinsic to certain particles.</p>
<p>For example, a <em>kugelblitz</em> is a theoretical black-hole formed entirely of photons.  It would be indistinguishable from a regular black-hole.  If the process that formed the <em>kugelblitz</em> had a quadrupole moment (if, for example, the light that was being concentrated to form the black hole was coming from one direction) then the formation of the black hole would produce gravitational waves, without any matter being accelerated</p>
<p>In the inspiral of two black holes, much of the &quot;mass&quot; is actually in the form of kinetic and gravitational potential energy. It is this energy that powers the production of gravitational waves that can be detected from halfway across the observable universe.</p>

CC BY-SA 4.0
2023-06-09T20:03:05.947Z
2023-06-09T20:58:10.383Z
2023-06-09T20:58:10.383Z
James K
<p>as we know , both mass and energy can bend space-time , and we know that accelerate mass can radiate gravitational-wave , but my question is that :
bent space-time by energy can also radiate gravitational-wave?</p>

<general-relativity><gravitational-waves>
bent space-time by Energy can radiate gravitational-wave?
Hamidreza Abdollahi
# bent space-time by Energy can radiate gravitational-wave?

(Asked by: username_0 on 2023-06-09)

as we know , both mass and energy can bend space-time , and we know that accelerate mass can radiate gravitational-wave , but my question is that :
bent space-time by energy can also radiate gravitational-wave?

**Tags:** general-relativity, gravitational-waves

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## 1 answers

### Answer by username_1 on 2023-06-09. Score: 3 | Accepted answer

General relativity makes no distinction between "mass" and "energy". Mass is just one form of energy, a form that happens to be intrinsic to certain particles.

For example, a *kugelblitz* is a theoretical black-hole formed entirely of photons. It would be indistinguishable from a regular black-hole. If the process that formed the *kugelblitz* had a quadrupole moment (if, for example, the light that was being concentrated to form the black hole was coming from one direction) then the formation of the black hole would produce gravitational waves, without any matter being accelerated

In the inspiral of two black holes, much of the "mass" is actually in the form of kinetic and gravitational potential energy. It is this energy that powers the production of gravitational waves that can be detected from halfway across the observable universe.


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