# Warping Space Time By Focusing on Getting Smaller Rather Than More Energy?

So all energy/mater warps space-time, right? However, whenever we talk about the human manipulation of space-time it is a far-off goal requiring nothing short of tremendous amounts of energy and moving synthetic black holes around.

I don't know much about the mechanics of how space-time warps, but could the problem be addressed by focusing on density instead of unobtainable amounts of mass or energy?

Like although beyond anything currently available, isn't it true that for a laser of a finite energy if you were to focus it on a tremendously small point in space the local energy density would become sufficient to warp space time? Or perhaps a high enough energy particle collision? How do the mechanics work with "local super-dense concentrations of energy vs. a large voluminous body like a star? Just curios.

Also, for all of you really smart folk out there, someone give me something to hold on to that warp drive might be possible some day : )

I don't know about warp drives, but you are correct that energy density is what warps space time. In classical General Relativity you could compress any object down to a size where it becomes a black hole. The radius for this is called the Schwarzschild radius. It is given as, $$r = \frac{2GM}{c^2},$$ where $$G$$ is Newton's gravitational constant, $$c$$ is the speed of light, and $$M$$ is the mass. You can even calculate your own Schwarzschild radius with this formula (assuming you are spherical).

Hypothetically you could form a black hole purely from photons. This has the fantastic name "Kugelblitz" which you can read more about here: https://en.wikipedia.org/wiki/Kugelblitz_(astrophysics)

The difficulty with these topics is that we are talking about large energies at very small distances meaning we need both General Relativity and Quantum Mechanics. These notoriously do not play well together and require extensions of our current understanding of physics (like string theory and/or extra dimensions).

There are actually active searches for microscopic black hole creations in particle collisions at the LHC. They use these to set limits on the sizes of extra dimensions as mentioned here https://home.cern/science/physics/extra-dimensions-gravitons-and-tiny-black-holes

Back to your main question, this ultimately comes down to a question of scale. A large object will curve spacetime around it at large scales, a small object will also curve space time around it but at smaller scales. If the sun were compressed into a black hole but kept at the same distance, Earth would still feel the same gravitational attraction as it does now.

In theory, ultra-high-energy particle collisions (in the Standard Model, well above the energy of the LHC) could create micro black holes. But they would immediately evaporate into elementary particles via Hawking radiation.

Laser beams can’t be sufficiently focused to make a micro black hole. If somehow they could be, the hole would again quickly evaporate.

Only astrophysical events, and perhaps the Big Bang, produce black holes massive enough to have long lifetimes.

Even if micro black holes were stable, you can’t build a warp drive out of them. Even if white holes and wormholes are real (and there is no evidence that they are), you can’t use a micro one to tunnel anywhere because you couldn’t fit into it and if you could you would be crushed.

Bottom line: Don’t expect a warp drive to be possible, because you are likely to be disappointed if you do. Find something else to look forward to.