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[Urist Arrhenius]

Scientists create invisible objects in the microwave range without metamaterial cloaking

That is hella cool, or at least the implications are.

It's pretty neat, but the fact that the invisibility is only at select wavelengths is a gigantic limitation.

I'm having an issue understanding the uncertainty principle. Is it really that the "true" position and momentum of say an electron is really uncertain in units of hbar, or that we just can't say anything about it since the forces that allow us to detect particles are all quantized and statistical? I know there's degeneracy pressure in neutron stars due to the uncertainty, but, again, that could be due to the forces being quantized.

It depends on who you ask. Those who take a probabilistic point of view will say that the "true" position is a funky concept, because the electron actually exists as a probability wave. And as you shrink the position distribution you increase the momentum distribution. There are those who would claim we just an't measure it accurately, but it's a minority.

[wierd]

It's a minority for a reason.  Quantum tunneling is required for the kind of nuclear fusion inside the sun to happen, and tunneling requires that atomic nuclei NOT be point objects.

Tunnelling is emprically observed as a phenomenon, the double slit experiment is an emperically observed phenomenon, and nuclear fusion is an emperically observed phenomenon.  Taken together, it pretty neatly nails the lid on that coffin.  Fundamentally, the particle/wave duality situation is an accurate depiction of what is happening, and not just a statistical contrivance.

[forsaken1111]

The fact that he can move at all while weighing close to a ton is ample evidence that there is magical weight reduction happening.

Power armor + super soldier strength.

That can only take you so far, and doesn't explain why he isn't tearing up the ground as he runs around. Or what is powering that kind of movement in such a tiny suit.

I mean there are all kinds of problems with the technology that they just handwave away. I'm not sure why you're trying to shoehorn fiction into reality. How does he dispose of the heat? That kind of power use would put out a lot of BTU in waste unless we also have magically efficient mechanisms and lossless power transfer.

Honestly if you're in a civilization with lossless power transfer, gravity manipulation, frictionless bearings, superfluids which can disperse/eliminate huge amounts of kinetic energy... why are we at war? And why use a man in a suit? It is literally the least efficient way of applying those technologies to warfare that I can think of.

[i2amroy]

The reason I pointed it out was the earlier discussion of surviving an uncontrolled fall from orbit. An object with the mass of a person has a terminal velocity of something like 200 km/h. So what kind of energy are you looking at for a man-sized object (say 80 kilos) moving at 200km/h and impacting feet-down?

Small note, but 200 km/h is approximately terminal velocity while you are on your stomach/back, terminal velocity with your feet pointed down is much closer to 200 mph (321.8 km/h) on average with people having reached top speeds closer to around 300 mph when trying to break that record. It's one of the reasons why most of my plans in the original discussion involved you falling spread-eagled and then flipping feet down at the last moment for the dramatic landing.

[forsaken1111]

The reason I pointed it out was the earlier discussion of surviving an uncontrolled fall from orbit. An object with the mass of a person has a terminal velocity of something like 200 km/h. So what kind of energy are you looking at for a man-sized object (say 80 kilos) moving at 200km/h and impacting feet-down?

Small note, but 200 km/h is approximately terminal velocity while you are on your stomach/back, terminal velocity with your feet pointed down is much closer to 200 mph (321.8 km/h) on average with people having reached top speeds closer to around 300 mph when trying to break that record. It's one of the reasons why most of my plans in the original discussion involved you falling spread-eagled and then flipping feet down at the last moment for the dramatic landing.

Fair enough. I was doing math on a napkin using figures I recalled from a previous conversation so I'm not surprised I missed something.

[Cryxis, Prince of Doom]

Halo is 500 some years in the future
Look at what we pulled off in just 100 years, I'm sure we can do that with 500

[Bauglir]

Halo is 500 some years in the future
Look at what we pulled off in just 100 years, I'm sure we can do that with 500

I'm sure we'll be able to pull off drops from orbit and generally achieve the same practical results, but just as humanity has not yet mastered the power of flight with our meaty, natural-born hands alone, we're probably not going to be doing it in that particular fashion. That is, in a person-sized suit that tries to straight-up tank the sheer impact. More likely some sort of largish pod with either thrusters or a parachute.

[penguinofhonor]

.

[Tylui]

www.muppetlabs.com/~breadbox/txt/al.html?fark

I'm sure this has been posted before but it's awesome!

[iceball3]

Here's a good question for everybody, namely because i am unsure. Maybe it's a weird interaction with General Relativity and conventional physics, but...
If the universe is constantly expanding, isn't the Gravitational Potential between all objects also increasing? Albeit it could be explained away with dark energy.. In which case it's understandable why i have a hard time mentalizing the energy balances. Even regarding, what is all of your folks thoughts on the general idea or specifics involved?

[Cryxis, Prince of Doom]

Halo is 500 some years in the future
Look at what we pulled off in just 100 years, I'm sure we can do that with 500

I'm sure we'll be able to pull off drops from orbit and generally achieve the same practical results, but just as humanity has not yet mastered the power of flight with our meaty, natural-born hands alone, we're probably not going to be doing it in that particular fashion. That is, in a person-sized suit that tries to straight-up tank the sheer impact. More likely some sort of largish pod with either thrusters or a parachute.

Upon viewing halo 4 intro spartan suits have thrusters on the back and reading more into it, the fall was controled and not just falling out of control.

[XXXXYYYY]

Here's a good question for everybody, namely because i am unsure. Maybe it's a weird interaction with General Relativity and conventional physics, but...
If the universe is constantly expanding, isn't the Gravitational Potential between all objects also increasing? Albeit it could be explained away with dark energy.. In which case it's understandable why i have a hard time mentalizing the energy balances. Even regarding, what is all of your folks thoughts on the general idea or specifics involved?

Hmm. I'm guessing that it's the same reason that grav. potential energy (relative to Earth) isn't all that relevant for, say, Voyager- They've long passed the rather severe drop-off point due to the difference. When you couple that with just the sheer, magnificent scale and speed the cosmos moves at,  it fades to the point of meaninglessness, so you end up with all the potential energies more or less canceling with all the other innumerable potential energies in the opposite direction.

That's just my (uninformed) intuition, though, so take it with a grain of salt.

Spoiler: off-topic universe rambling (click to show/hide)

But, man. The sheer scale of the universe is near incomprehensible. I mean, 92 billion light years in diameter, wow. 540821983000000000000000 miles across. After a certain point, the mind just gives up and says 'that's a ton of damn zeroes.' And then you look at that number, and then you realize that the universe in total volume is 3.261760666984705x10³³ cubic light years, and the brain quits and goes off on a vacation. In comparison, the earth with all of its people and history is only 1.279 x 10^-27 lightyears³. In total, that amounts to the universe being 2.547x 10⁶⁰ times bigger than Earth. This isn't even all that surprising, but it just hammers in the point that we are absolutely minuscule, if you compare us to all that exists. All the sorrows, joys, suffering, and experiences that most humans will ever experience is going to be confined such a tiny speck in some tiny portion of the universe. Just some food for thought.

Yeah, those numbers about relative size still seem a bit too large in favor of Earth, so I probably fucked up somewhere, but whatev.

[Cryxis, Prince of Doom]

And that's only the observable universe correct?

[Putnam]

Literally the only part of the universe that matters.

I'm not using literally in the figurative sense, either; there is absolutely no possible way for anything outside the observable universe to affect Earth. That's kinda the definition of the observable universe.

[wierd]

Only if it is genuinely impossible to have functional FTL. 

(I sometimes wonder about the possibility of "extremely humongous" wormholes existing. Wormholes SO BIG, that they look like normal space-time other than mysterious matter flow patterns around them. Kinda like the great attractor actually.  If such objects exist in the universe, then "local shortcuts" between parts of the universe normally outside our lightcone could be possible.)