Military Has Been Researching "Anti-Gravity" For Nearly 70 Years • Hacker News Board

Re: Military Has Been Researching "Anti-Gravity" For Nearly 70 Years

#61

Post by duchenne » Thu, Oct 31, 2019, 7:30 AM UTC

I love the following Feynman's quote:

``In those days, one of the theories proposed was that the planets went around because behind them were invisible angels, beating their wings and driving the planets forward. You will see that this theory is now modified! It turns out that in order to keep the planets going around, the invisible angels must fly in a different direction and they have no wings. Otherwise, it is a somewhat similar theory!``

The point is that, still today, we have no idea why mass attracts mass. We observe it. We measure it. We model it. We predict it. But, we do not understands its mechanism. At that time, it was making people crazy to think that an object could remotely affect another one. Now, people just accept it. But, when you think about it, it really sounds magic.

Re: Military Has Been Researching "Anti-Gravity" For Nearly 70 Years

#62

Post by Brotkrumen » Thu, Oct 31, 2019, 7:42 AM UTC

ISL wrote: post #47

jeffdavis wrote: post #44

Earlier quoted context omitted.

Assuming we find dark matter, do you think it will represent some departure from our current understanding of gravity and how it relates to mass? Or do you think it will just be some boring dust clouds?

We have already tested the equivalence principle toward dark matter [1]. It appears to fall like everything else, at the 1% or better level. It is extremely difficult for modifications of gravity to simultaneously fit the cosmic microwave background, big-bang nucleosynthesis, galactic rotation curves, and the Bullet Cluster. The safe bet these days is on some sort of non-baryonic dark particle (which is why so many p…

this is all fine and dandy, but when do you think will we have anti-grav drives?

Re: Military Has Been Researching "Anti-Gravity" For Nearly 70 Years

#63

Post by pmorais » Thu, Oct 31, 2019, 7:42 AM UTC

dvh wrote: post #42

newsbinator wrote: post #39

What is the currently accepted answer to the question, "what is gravity"?

Gravity is one of the essential forces in nature. If you want to explain it in simpler terms it is not possible because gravity is the simpler thing. You can use gravity to explain other things, but you cannot use other things to explain gravity.

That’s not really true. The other 3 “fundamental” forces are irreducible yet still entirely explained by the standard model.

Re: Military Has Been Researching "Anti-Gravity" For Nearly 70 Years

#64

Post by croh » Thu, Oct 31, 2019, 7:47 AM UTC

duchenne wrote: post #61

I love the following Feynman's quote: ``In those days, one of the theories proposed was that the planets went around because behind them were invisible angels, beating their wings and driving the planets forward. You will see that this theory is now modified! It turns out that in order to keep the planets going around, the invisible angels must fly in a different direction and they have no wings. Otherwise, it is a s…

Thus journey in spirituality starts.

Re: Military Has Been Researching "Anti-Gravity" For Nearly 70 Years

#65

Post by lliamander » Thu, Oct 31, 2019, 7:47 AM UTC

duchenne wrote: post #61

I love the following Feynman's quote: ``In those days, one of the theories proposed was that the planets went around because behind them were invisible angels, beating their wings and driving the planets forward. You will see that this theory is now modified! It turns out that in order to keep the planets going around, the invisible angels must fly in a different direction and they have no wings. Otherwise, it is a s…

> At that time, it was making people crazy to think that an object could remotely affect another one.

Astrology?

Re: Military Has Been Researching "Anti-Gravity" For Nearly 70 Years

#66

Post by hoseja » Thu, Oct 31, 2019, 7:51 AM UTC

lisper wrote: post #46

ISL wrote: post #27

Physicists have been searching for variations in the coupling of materials to gravity for more than a century, and by some measure, for more than a millenium. https://en.wikipedia.org/wiki/Equivalence_principle#Tests_of... Every experiment anyone has ever tried has come up empty. The equivalence principle is a postulate (Einstein's "happiest idea") that underlies General Relativity, making it essential to test. (Sour…

How much money does society need to spend supporting the work you do before we can safely conclude that Einstein was actually correct and we don't need to test it any more?

Would be much better to spend that money on another VC funding round for WAaaS (Wiping Asses as a Service)!

Re: Military Has Been Researching "Anti-Gravity" For Nearly 70 Years

#67

Post by nootropicat » Thu, Oct 31, 2019, 7:55 AM UTC

danschumann wrote: post #18

To really be able to manipulate gravity, you would also need to manipulate mass, and so far nuclear is the only way I know of, in which we do that, but uhh.. I don't think we'll get anti gravity until we can control mini stars... Little nuclear engines.

Gravity is a property of energy, of which mass is one form. That means a laser beam attracts other energy via gravity.

Re: Military Has Been Researching "Anti-Gravity" For Nearly 70 Years

#68

Post by ISL » Thu, Oct 31, 2019, 7:58 AM UTC

Brotkrumen wrote: post #62

ISL wrote: post #47

Earlier quoted context omitted.

We have already tested the equivalence principle toward dark matter [1]. It appears to fall like everything else, at the 1% or better level. It is extremely difficult for modifications of gravity to simultaneously fit the cosmic microwave background, big-bang nucleosynthesis, galactic rotation curves, and the Bullet Cluster. The safe bet these days is on some sort of non-baryonic dark particle (which is why so many p…

this is all fine and dandy, but when do you think will we have anti-grav drives?

Don't bet more than you can afford to lose.

Re: Military Has Been Researching "Anti-Gravity" For Nearly 70 Years

#69

Post by nnq » Thu, Oct 31, 2019, 8:16 AM UTC

lisper wrote: post #46

ISL wrote: post #27

Physicists have been searching for variations in the coupling of materials to gravity for more than a century, and by some measure, for more than a millenium. https://en.wikipedia.org/wiki/Equivalence_principle#Tests_of... Every experiment anyone has ever tried has come up empty. The equivalence principle is a postulate (Einstein's "happiest idea") that underlies General Relativity, making it essential to test. (Sour…

How much money does society need to spend supporting the work you do before we can safely conclude that Einstein was actually correct and we don't need to test it any more?

Hopefully a (theoretically) infinite amount (assuming infinite time) ...theories should continuously be re-tested, although it probably makes sense to spend an exponentially lower and lower amount of money on re-testing theories we know are true. But they should be re-tested, even if some experiments you'd only redo every 50 years or so!

For two important reasons:

1. as a species we must maintain technical capability to perform certain types of experiments - only way to 100% be sure we do this is by re-doing those experiments periodically

2. the fact that the "laws" of physics are fixed in any sense of the word, or that there even are such things as "laws of nature" is at its core a very very likely but UNPROVEN ASSUMPTION... we should always be open to the possibility that we live in a much stranger universe than we imagine and that the laws of physics themselves could vary and that we mush have capability to re-discover the new/changed laws, or to poke deeper at meta-laws

Also (2) is not as much lunacy as it sounds considering that the most likely (in the sense of "mathematically probable" considering the math of probability and information, not in "what we can determine experimentally with our primitive capabilities") setup from our universe models is more like we're in an N-th level "simulation" (a simulation in a simulation ... etc.) maybe running on a something like a "Boltzmann brain" in hell knows what soup of multiverses...

We may live insignificantly short lives and be practically meaningless on a grander scale, but if we dare the play the game of "guessing the laws of the universe" on a large scale, we shouldn't have the arrogance to assume that what we measure and deduce on an insignificantly small space-time volume in our ant-farm corner of the universe actually holds up directly through longer stretches of time and space!

Otherwise we're not really doing science, we're adherents to the religion called scientism, and we're not truly honestly rational, but merely praying in the church of rationalism! These are very very different things!

Re: Military Has Been Researching "Anti-Gravity" For Nearly 70 Years

#70

Post by rurban » Thu, Oct 31, 2019, 8:19 AM UTC

duchenne wrote: post #61

I love the following Feynman's quote: ``In those days, one of the theories proposed was that the planets went around because behind them were invisible angels, beating their wings and driving the planets forward. You will see that this theory is now modified! It turns out that in order to keep the planets going around, the invisible angels must fly in a different direction and they have no wings. Otherwise, it is a s…

Gravity is very similar to magnetism, a "magically" attracting force of distinct objects. The explanation is very easy via fields. Just trying to explain it via particles will get you into trouble, e.g. the flawed standard model, or the Higgs.

Einstein was pretty close in his spacetime bending explanation, but this still doesn't explain dark matter or the recent gravity experiments with fast rotating magnets in strong supra conductors. There are better gravity field theories out there, but they are lacking experimental verification. Some experiments are cheap, but most are cosmic scale, beyond simple galaxies.

This army guy came up with nice and cheap experiments, similar to Tajmar's experiments. We will see what will come out of it. Tajmar is also holding an old patent of an Anti-Gravity device, which nobody built so far. The army device with two rotating fields seems to be much better.