Recent content by bubal

If you were suspended inside and iron armor between an electromagnet and the ground it is obvious that you would feel your weight against that armor, but when a frog is suspended by diamagnetic levitation I understand that it feels weightlessness. If this is correct, that means that if it were...

Let's perform a thought experiment. Imagine that the Universe was smaller, only Laniakea, or even smaller, only the Local group. In this case you could be at the far edge of Andromeda and see the dark emptiness, unless you saw the Milky way on both sides. (In case that the Universe is closed...

Imagine someone in a planet at the farthest star of the farthest galaxy from ours. From that planet would the sky be a half black and the other half full of galaxies? Could a star be at the "edge" of the universe or general relativity contradicts that?

So could it be a kind of Ventury effect?

Yes. A vortex smoke ring or an air vortex, like the ones from air vortex cannons. It is in the middle of the air so you don't have surfce tension. The particles in the vortex are rotating around a circular line and they are free. (Other vortices like a whirpool in a sink are not free because the...

I am trying to understand what forces keep a free vortex, (i.e. a vortex ring). Its rotating particles must have a force to avoid them going out (like gravity on planets). I have read about vortices and vorticity, but get lost in equations. Is it possible to explain the force that keep the...

Imagine a mass that disappeared from space. I know that it is impossible, but imagine it is sucked by a wormhole or it just disapperars. Will we detect ONE gravitational wave only? Like a pulse and nothing else? Now the other way around. A mass appears from nothing. Then we will detect one...

@Crazymechanic. Perhaps you didnt understand the question. I stated "Neutrons thought experiments. ". A thought experiment, originally named in German Gedankenexperiment is an hypothesis. i.e. an train that runs at 99% of the speed of light. I UNDERSTAND that it is impossible such train, but it...

1. i.e. 1 mm/sec speed, I mean the smothest speed you can imagine. Do the bounce or glue? 2. Yes I posed a question, read the beginning, What would happen if: A rainfall of neutrons... The question is what would happen with the neutrons, do they "live" mixed with the water, do they...

What would happen if: 1- Two neutrons approach each other slowly. Do they glue? 2- A rainfall of neutrons fell to the Earth. I mean very slowly (very low energy) and a huge amount, the same mass as the oceans, i.e. Thank you very much!.

Perhaps because fire, bonfires are red-yellow. Embers are red. Hot metal is red. Volcanoes lava is red... On the other hand. Ice is sometimes bluish. Cloudy days are of higher color temperature, this is more bluish. The sea is blue. The heat is infrared and we are not sensitive to light...