# Can gravity make gravity? **URL:** \ **Category:** Factual Questions\ **Created:** [November 13, 2024, 9:38pm UTC](https://boards.straightdope.com/t/can-gravity-make-gravity/1010220 "2024-11-13T21:38:26Z")\ **Posts on this page:** 9\ **Page:** 1
**Author:** ![EnolaStraight](https://avatars.discourse-cdn.com/v4/letter/e/41988e/32.png) [@EnolaStraight](https://boards.straightdope.com/u/EnolaStraight)\ **Post date:** [November 13, 2024, 9:38pm UTC](https://boards.straightdope.com/t/can-gravity-make-gravity/1010220/1 "2024-11-13T21:38:26Z")
Mass distorts spacetime: this distortion is gravity. Energy equals mass time the speed of light squared. If matter and energy are equivalent/interchangeable, then energy can create gravity, too…yes? In this thread, [Could gravitational waves be an alternative to dark matter or dark energy? - In My Humble Opinion - Straight Dope Message Board](https://boards.straightdope.com/t/could-gravitational-waves-be-an-alternative-to-dark-matter-or-dark-energy/825671/4) Chronos describe how two black holes merging released several suns’ mass worth of gravitic energy. Is gravity borne/begat by gravitic energy a thing in General Relativity? In the galaxy, could gravity begat by gravity explain Dark Matter? In the massless voids between galaxies, could the lack of mass, gravity, and “begotten” gravity explain Dark Energy? ---
**Author:** ![Der\_Trihs](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/der_trihs/32/233_2.png) [@Der\_Trihs](https://boards.straightdope.com/u/Der_Trihs)\ **Post date:** [November 13, 2024, 9:49pm UTC](https://boards.straightdope.com/t/can-gravity-make-gravity/1010220/2 "2024-11-13T21:49:40Z")
Not a physicist but IIRC it does create gravity; it’s energy and energy distorts spacetime like matter does. But no, it’s something long known and can’t explain dark matter or dark energy. Both because it’s not a big enough effect and because it was an already known effect before those issues came up. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [November 13, 2024, 9:53pm UTC](https://boards.straightdope.com/t/can-gravity-make-gravity/1010220/3 "2024-11-13T21:53:05Z")
@Der_Trihs has the right of it. Gravity does, itself, gravitate (though as you can imagine, in any situation where this actually becomes relevant, it’s a bitch to calculate it). And this doesn’t explain dark matter nor dark energy. ---
**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\ **Post date:** [November 14, 2024, 12:58pm UTC](https://boards.straightdope.com/t/can-gravity-make-gravity/1010220/4 "2024-11-14T12:58:47Z")
Have you heard of a _kugelblitz_? > [@](#): > > A **kugelblitz** (German: [[ˈkuːɡl̩ˌblɪt͡s]](https://en.wikipedia.org/wiki/Help:IPA/Standard_German) [ⓘ](https://en.wikipedia.org/wiki/File:De-Kugelblitz.ogg)) is a [theoretical](https://en.wikipedia.org/wiki/Theoretical_physics) astrophysical object predicted by [general relativity](https://en.wikipedia.org/wiki/General_relativity). It is a concentration of [heat](https://en.wikipedia.org/wiki/Heat), [light](https://en.wikipedia.org/wiki/Light) or [radiation](https://en.wikipedia.org/wiki/Radiation) so intense that its energy forms an [event horizon](https://en.wikipedia.org/wiki/Event_horizon) and becomes self-trapped. In other words, if enough [radiation](https://en.wikipedia.org/wiki/Radiation) is aimed into a region of space, the concentration of energy can warp [spacetime](https://en.wikipedia.org/wiki/Spacetime) so much that it creates a [black hole](https://en.wikipedia.org/wiki/Black_hole). This would be a black hole whose original [mass–energy](https://en.wikipedia.org/wiki/Mass%E2%80%93energy_equivalence) was in the form of [radiant energy](https://en.wikipedia.org/wiki/Radiant_energy) rather than matter;[[1]](https://en.wikipedia.org/wiki/Kugelblitz_(astrophysics)#cite_note-1) however, there is currently no uniformly accepted method of distinguishing black holes by origin. > **[Kugelblitz (astrophysics)](https://en.wikipedia.org/wiki/Kugelblitz_(astrophysics))** > > A kugelblitz (.mw-parser-output .IPA-label-small{font-size:85%}.mw-parser-output .references .IPA-label-small,.mw-parser-output .infobox .IPA-label-small,.mw-parser-output .navbox .IPA-label-small{font-size:100%}German: \[ˈkuːɡl̩ˌblɪt͡s\] ⓘ) is a theoretical astrophysical object predicted by general relativity. It is a concentration of heat, light or radiation so intense that its energy forms an event horizon and becomes self-trapped. In other words, if enough radiation is aimed into a region of sp... ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [November 15, 2024, 1:43am UTC](https://boards.straightdope.com/t/can-gravity-make-gravity/1010220/5 "2024-11-15T01:43:06Z")
More fun with kugelblitzen: Imagine you’re in the center of one, as its forming. Since the incoming radiation that forms it is moving at the speed of light, you won’t know about it until it reaches you. Which is after the time at which it forms the event horizon. Which means that it’s possible to cross an event horizon without having any knowledge at all, even theoretical, of that as it’s happe ---
**Author:** ![Pleonast](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pleonast/32/1183_2.png) [@Pleonast](https://boards.straightdope.com/u/Pleonast)\ **Post date:** [November 15, 2024, 2:04am UTC](https://boards.straightdope.com/t/can-gravity-make-gravity/1010220/6 "2024-11-15T02:04:34Z")
> [@Chronos](#): > > Which means that it’s possible to cross an event horizon without having any knowledge at all, even theoretical, of that as it’s happe I fear the worst for @Chronos, crossing the event horizon mid sentence. ---
**Author:** ![EnolaStraight](https://avatars.discourse-cdn.com/v4/letter/e/41988e/32.png) [@EnolaStraight](https://boards.straightdope.com/u/EnolaStraight)\ **Post date:** [November 15, 2024, 11:09pm UTC](https://boards.straightdope.com/t/can-gravity-make-gravity/1010220/7 "2024-11-15T23:09:32Z")
Which means that it’s possible to cross an event horizon without having any knowledge at all, even theoretical, of that as it’s happe _I see what you did there. 😉_ ---
**Author:** ![wolfpup](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wolfpup/32/10618_2.png) [@wolfpup](https://boards.straightdope.com/u/wolfpup)\ **Post date:** [November 15, 2024, 11:23pm UTC](https://boards.straightdope.com/t/can-gravity-make-gravity/1010220/8 "2024-11-15T23:23:43Z")
> [@EnolaStraight](#): > > If matter and energy are equivalent/interchangeable, then energy can create gravity, too…yes? IANAP, but this seems to be just trivially true, since energy and mass are indeed interchangeable. It’s just that, in our everyday terms, it takes an incredibly enormous amount of energy to have any measurable mass, and conversely, very little mass to create enormous energy. Quote from Wikipedia: > [@CalMeacham](#): > > however, there is currently no uniformly accepted method of distinguishing black holes by origin. And AFAIK there never can be, as the only discernible properties of a black hole are mass, spin, and charge. By definition of an event horizon, no other properties are observable, so “origin” information is unknowable. ---
**Author:** ![Crafter\_Man](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crafter_man/32/458_2.png) [@Crafter\_Man](https://boards.straightdope.com/u/Crafter_Man)\ **Post date:** [November 16, 2024, 1:53am UTC](https://boards.straightdope.com/t/can-gravity-make-gravity/1010220/9 "2024-11-16T01:53:29Z")
> [@CalMeacham](#): > > **Kugelblitz** That’s a band name if I ever heard one.