Major astrophysics discovery to be unveiled on Monday.

[Fritzo]

have any links

This is brand new research, but it looks pretty exciting:

https://www.simonsfoundation.org/quanta/20130917-a-jewel-at-the-heart-of-quantum-physics/

 

[OutHouse]

Why the fuck does it have to be something that's 'practical' for you? Oh right, because it might explain the origins of the universe and that goes against your batshit crazy rightwing religious 'theories'.

Off your meds again?

 

[Hayabusa Rider]

so what does space time exist in then

It exists as itself. Whether it is a fundamental entity or a result of something deeper (as fritzo's link suggests) it exists and doesn't need anything else.

To paraphrase "It is that it is." You are doing something completely natural which to look at this in terms of everyday experience. If something is in a box then the box is inside of something else. That's perfectly fine as long as we understand that we're talking about things within the universe. The universe? It is by definition itself and it has things in it.

There's an analogy of an inflating balloon with dots representing galaxies getting further apart as it expands. It's an analogy which is useful in understanding principles which apply in higher dimensions. Let's take advantage of this and pretend there is a very large surface (note for this purpose "surface" relates to the highest possible number of dimensions someone "on" it can travel) and a 2D person gets on the internet of their accessable reality and asks "where's the edge of the cosmos?"

Well, from our higher dimensional perspective it's easy to see that there isn't an edge. The 3d shape has definite size, but one could wander forever and never walk off the edge. There isn't an edge at all. On Flatland however they only have two perpendiculars. They can go left or right, forwards or back, or some direction which can be broken down like vector diagrams in grade school written on graph paper.

Something else it helps to grasp is the recession of galaxies, where everything seems to be moving away from an observer in such a way that it makes one think he or she is the center of the universe. They aren't though. Their surface, their spacetime, is growing and from every point thing appear this way.

This works so well that we apply it to ourselves. We live on a 3D surface we call "volume" and all our data and theory leads to the conclusion that the real, not some imagined, universe is pulled into some 4 dimensional shape. We are confined to it like Flatlanders, however there is one difference. There is no higher spatial dimension we can appeal to. Whether there is one is absolutely irrelevant from our perspective because we cannot know anything about it. We can't look "up" and out of our reality. Ever. Now it may be that we can determine the nature of the 4D manifold we inhabit by clever means, but that's it. The analogy breaks down when you go outward because it's impossible to experience or visualize that which you can't possibly reach. Out of bounds. So what are we left with? That which is, that we can access, know about, test. Is it absolutely all that there is? No one can ever say, but even more it is utterly unknowable even in principle. It may be an unsatisfying answer, but there is nowhere written in the fabric of reality that we get what we want.

 

[Ruptga]

there are various issues that i may or may not have issues with but some of them might be small.

something i have more problem with is that an object could have no mass or volume.

are they sure they do not just mean very little mass and volume?

Oh shit stop the presses, our newest resident lunatic has a problem with theoretical physics! It it too late for a retraction?

 

[Paul98]

This also tells us about other theories, which are wrong or need to be adjusted. Along with ones who's predictions correspond's with their results.

 

[disappoint]

More interesting to me is the interaction of gravity waves and EM fields. How much longer until gravity is integrated and we finally have a unified "theory of everything"?

Gravity waves are ripples or waves in the fabric of spacetime. Since EM waves are traveling through spacetime they must follow the path of those waves so the 'interaction' should take place. If it didn't take place that would be strange and unanticipated.

It seems as if at first you pictured gravity waves as some other entity traveling through spacetime instead of changes in the geometry of spacetime itself. I hope this post clears up any misconceptions some might have.

 

[Dude111]

The world is not flat and we are floating through space on a raft called Earth?

We all know that bud!!

 

[z1ggy]

My question that I can never really wrap my mind around (maybe because I haven't bothered to research) is what is the "stuff" that fills the voids between masses? Like, when astronauts are out space walking, what is the "medium" they are in? There's obviously no air molecules or other ions, it's just filled with radiation, photons, etc etc.. But I guess I just can't seem to see how there is nothingness. Is it the so called dark matter/energy I always read about? I always felt it odd to think about if our universe is actually expanding, yet finite, that it's bounds must be mad some something. Just conceptually difficult to visualize at times for me.

 

[Paratus]

My question that I can never really wrap my mind around (maybe because I haven't bothered to research) is what is the "stuff" that fills the voids between masses? Like, when astronauts are out space walking, what is the "medium" they are in? There's obviously no air molecules or other ions, it's just filled with radiation, photons, etc etc.. But I guess I just can't seem to see how there is nothingness. Is it the so called dark matter/energy I always read about? I always felt it odd to think about if our universe is actually expanding, yet finite, that it's bounds must be mad some something. Just conceptually difficult to visualize at times for me.

Well according to quantum mechanics the vacuum is not empty. It's filled with "virtual" particles that pop in and out of existence for infinitesimal amounts of time. Do a search for quantum vacuum fluctuations.

Actually the group at my work I posted about earlier that was working on warping space, is also looking at a test thruster that doesn't require carried propellant. They are looking at pushing off these virtual particles in what's called a quantum vacuum plasma thruster.

So basically they are working on impulse power and warp drive.

 

[norseamd]

so how close are we to the vasimir drive? also is there anything holding us back from making a fission electric rocket right now? not for getting into space but for propulsion in space to like mars?

 

[z1ggy]

Well according to quantum mechanics the vacuum is not empty. It's filled with "virtual" particles that pop in and out of existence for infinitesimal amounts of time. Do a search for quantum vacuum fluctuations.

Actually the group at my work I posted about earlier that was working on warping space, is also looking at a test thruster that doesn't require carried propellant. They are looking at pushing off these virtual particles in what's called a quantum vacuum plasma thruster.

So basically they are working on impulse power and warp drive.

Right, I get that. That explains why space is not at absolute zero temp, it's something above that (forget what though).

It's just an odd thought process to try and bound the universe and space time as we could imagine say a balloon. If it isn't infinite, then there is somehow a point at which light hasn't yet reached... So a boundary of sorts. How that boundary contains what we define as our universe puzzles me.

Interesting concept w the thrust. I also read a paper the other day about a few PhD's who submitted a paper on how to create artificial black holes (zero angular momentum, zero charge) to power space craft via Hawking Radiation.

 

[JTsyo]

The problem is you'd have to wear a protective suit to use it because the amount of energy needed to cut through walls/railings/arms would fry anyone within several feet of it.

Unfortunately light sabers are in that "probably never feasible" category.

Maybe you can make a cylinder shaped field like the Dr. Little weapon in Ender's Game. Then whatever you "cut through" would just have their bonds broken and give you almost the same effect. Though there would be no cauterizing the wound.

 

[CPA]

Why the fuck does it have to be something that's 'practical' for you? Oh right, because it might explain the origins of the universe and that goes against your batshit crazy rightwing religious 'theories'.

Stop being an idiot Phokus. i'm far from being religious. I'm asking from the standpoint of Joe Public who doesn't have a clue about this stuff and it's importance to me or society. Will we see tangible applications as a result of this discovery? Is there an endgame? Or does all this do is create more questions and more theories?

But by all means continue on with your non-stop religion and politic diatribe.

 

[Vdubchaos]

Didn't they just discover star creating something with Hubble?

Maybe they will rewrite the entire big bang theory.....

 

[Paratus]

Right, I get that. That explains why space is not at absolute zero temp, it's something above that (forget what though).

It's just an odd thought process to try and bound the universe and space time as we could imagine say a balloon. If it isn't infinite, then there is somehow a point at which light hasn't yet reached... So a boundary of sorts. How that boundary contains what we define as our universe puzzles me.

Interesting concept w the thrust. I also read a paper the other day about a few PhD's who submitted a paper on how to create artificial black holes (zero angular momentum, zero charge) to power space craft via Hawking Radiation.

Actually it's the cosmic background radiation leftover from the Big Bang that means we don't see absolute zero. That radiation is made of "real" photons. These vacuum fluctuations are the same thing that drive Hawking radiation and only exist for a tiny amount of time unless you can pump enough energy, (E=mc^2), into the vacuum to turn them "real". Black holes are theorized to do this.

As for the Q-thruster, if it can make it out of the lab it would open the entire solar system to exploration in reasonable amounts of time. Probes to Alpha Centauri would even be possible in one scientists career.

If the warp drive thing works out I guess it would be possible to reach the farthest expansion of the universe. :hmm:

 

[norseamd]

does this speed up the advancement of fusion power at all?

 

[z1ggy]

This is brand new research, but it looks pretty exciting:

https://www.simonsfoundation.org/quanta/20130917-a-jewel-at-the-heart-of-quantum-physics/

That's pretty cool. I hope in my lifetime they can link gravity to the rest of quantum mechanics.

In my eyes if the universe was born as we calculate in the big bang and all known information and physics was born at that time... all of physics was at one insanely small instant, one unified thing.

Would make sense that even if given current models can't relate gravity at a quantum level, that it's still woven into it somehow.

 

[manimal]

Well according to quantum mechanics the vacuum is not empty. It's filled with "virtual" particles that pop in and out of existence for infinitesimal amounts of time. Do a search for quantum vacuum fluctuations.

Actually the group at my work I posted about earlier that was working on warping space, is also looking at a test thruster that doesn't require carried propellant. They are looking at pushing off these virtual particles in what's called a quantum vacuum plasma thruster.

So basically they are working on impulse power and warp drive.

I have a man crush on Paratus. I had to do a double take and make sure I wasnt hallucinating and this was a post from patranus. He is your doppelganger.

 

[Fritzo]

Actually it's the cosmic background radiation leftover from the Big Bang that means we don't see absolute zero. That radiation is made of "real" photons. These vacuum fluctuations are the same thing that drive Hawking radiation and only exist for a tiny amount of time unless you can pump enough energy, (E=mc^2), into the vacuum to turn them "real". Black holes are theorized to do this.

As for the Q-thruster, if it can make it out of the lab it would open the entire solar system to exploration in reasonable amounts of time. Probes to Alpha Centauri would even be possible in one scientists career.

If the warp drive thing works out I guess it would be possible to reach the farthest expansion of the universe. :hmm:

Hyper velocities in space raise a lot of interesting questions. If we do make some sort of fast propulsion, it will probably be decades (if not centuries) before we'd be able to use it to cart humans around, simply because of shielding. At even .5c, a tiny pebble would hit the spacecraft with the energy of a hydrogen bomb. We just don't have the technology to protect anything going faster than around 100K mph.

There's lots of engineering involved in going fast besides an engine. Really makes you think.

 

[Paratus]

I have a man crush on Paratus. I had to do a double take and make sure I wasnt hallucinating and this was a post from patranus. He is your doppelganger.

D: :wub:

Mongo straight!


Patranus, my doppelgänger?! I've been here longer and don't have anus in my name!

 

[Paratus]

Hyper velocities in space raise a lot of interesting questions. If we do make some sort of fast propulsion, it will probably be decades (if not centuries) before we'd be able to use it to cart humans around, simply because of shielding. At even .5c, a tiny pebble would hit the spacecraft with the energy of a hydrogen bomb. We just don't have the technology to protect anything going faster than around 100K mph.

There's lots of engineering involved in going fast besides an engine. Really makes you think.

You don't have to tell me about the engineering. I spent the last decade helping put together the ISS.


While this is off topic . This is an interesting question.
The ISS actually gives us a framework for dealing with these hyper velocity hits.

For the ISS NORAD tracks all the space debris down to a certain size. Debris that comes near the ISS causes us to maneuver away from it.

For our hypothetical Interplanetary/Interstellar ship we'd mount RADAR or other forward looking sensors to track and avoid debris large enough to do significant damage.

For debris too small to track the ISS is equipped with Whipple shielding on the pressurized segments that should prevent these small particles from penetrating. Areas in the ram, forward direction, generally get beefier shielding.

For our ship, we'd do the same. Beefy shielding in the ram. Also inflatable modules such as Transhab canbe made to self seal for certain smaller holes.

If the ISS does get hit, we have redundant systems so a single lost box shouldn't take down a critical system. We also have repair capabilities and are working on developing robotic repair capabilities.

Our ship would have the same.

Other technologies that are coming along are magnetic shielding to reduce radiation exposure. Some group out of England I think had an article showing a model space craft directly in a plasma jet and the magnetic field was deflecting the particles around it. Of course this doesn't affect non charged particles, but it maybe possible to use a laser to heat dust in front of our ship quickly enough to ionize it and let the magnetic field push it out of the way. The navy is now testing solid state multiKW lasers on its ships.

(Edit: found the picture)


Any remaining risk would have to be accepted or the maximum velocity of our ship limited so the risk was manageable.

I'm not saying it's not difficult, just that there is a framework in place now to solve problems like this.

 

[norseamd]

when can we get the nautilus iss section running

 

[norseamd]

when can we get the nautilus iss section running

these forum has me posting as 6 hours ago. way too many errors happening recently. get anandtech working please thankyou

any answers to the question

 

[Paratus]

Testing

 

[norseamd]

paratus what about the natilus iss test section? might it be possible that they might make it and put it with the iss?