Merrith
Golden Baronet of the Realm
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The Astronomy Thread
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iannis
Musty Nester
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Interesting article, but I think they oversimplified. They make it sound almost arbitrary (the points they're talking about in the first third) and i'm sure it's not.
I even kind of know what they were talking about, Arkani-Hamed guy gave a lecture that I watched and he was talking about that type of symmetry. Just not this application of the idea.
I even kind of know what they were talking about, Arkani-Hamed guy gave a lecture that I watched and he was talking about that type of symmetry. Just not this application of the idea.
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Merrith
Golden Baronet of the Realm
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Mudcrush Durtfeet
Hungry Ogre
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Fourth re-use of a Falcon 9 booster (also first time they've reused the fairings). Go SpaceX!
www.space.com
SpaceX Just Launched 60 Starlink Satellites (And Nailed a Milestone Rocket Landing)
The same Falcon 9 just made its fourth launch and landing.
www.space.com
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iannis
Musty Nester
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Seems like it doesn't really suggest it.
Whatever the shape is, its becoming more suspciously not 3 dimensional. When they talk about flat, saddle, or curved they're talking about how lines interact over distance.
Assuming that inflation is correct and that the CMB is the visible remnant of it, that precludes the option of that kind of a closed universe. It doesn't preclude a closed universe, just the sort of "inside of a sphere" one.
There would be a uniform wall of light at a certain distance from us if that were true, no matter how much larger the universe is than our observable portion of it. And there is a wall of light, but it's not uniform.
Whatever the shape is, its becoming more suspciously not 3 dimensional. When they talk about flat, saddle, or curved they're talking about how lines interact over distance.
Assuming that inflation is correct and that the CMB is the visible remnant of it, that precludes the option of that kind of a closed universe. It doesn't preclude a closed universe, just the sort of "inside of a sphere" one.
There would be a uniform wall of light at a certain distance from us if that were true, no matter how much larger the universe is than our observable portion of it. And there is a wall of light, but it's not uniform.
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LachiusTZ
Rogue Deathwalker Box
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If that were the case, would so many that know more than us posit bubble universes etc?
Or am I missing some thing?
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iannis
Musty Nester
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No, pretty much exactly.
We do know that what we can observe with light is not possibly the whole thing. It's bigger. INfinite is a big concept and it might be. Doesn't have to be. Might just be big.
You might as well refer to the rest of it as a bubble. Or our observable universe as the bubble. If the region's are not causually linked (further away than even light can interact) they are sequestered.
LachiusTZ
Rogue Deathwalker Box
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Lol no
At deer camp so can't really type a good response. But nah dude. Lol
Ping me on this in like three days. Because if I don't understand this properly, I want to. And if I do, then we gotta correct you
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Tilion
Trakanon Raider
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The Merlin is an open cycle engine. That jet is most likely the exhaust of the gases used to power the turbo pumps.
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^
Those things don't just spring leaks without catastrophic consequences. It's ~3400 degrees and 100 atm in the combustion chamber. Even the fuel lines running in are already pre-heated and pressurized by passing through the bell material first. The fuel itself is the coolant.
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khorum
Murder Apologist
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preburner exhaust from the turbopump maybe? As far as I know the new raptor engines (for the starship) are the only closed/full flow engines spacex has made so far so all the old merlin and vulcan engines must still have some kinda preburner exhaust somewhere.
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Mudcrush Durtfeet
Hungry Ogre
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The Raptor engines are the only such engines in production, ever, as far as I know. Not quite being used for space travel yet, but soon.
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Tilion
Trakanon Raider
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Open cycle engines don't have to vent the preburner exhaust randomly out the side. Some, like the F-1 engine from the Saturn V and the Vulcain 2 from the Ariane 5, vent the gases back into the engine nozzle which creates a "cool" film and protects the nozzle from the main combustion chamber gases. If you watch videos of the Saturn V launch you see a dark band coming out of the nozzle, that is the cooler preburner exhaust gas.
The raptors are/will be the first full-flow closed cycle engine to fly, but there have been plenty of closed cycle engines with different preburner variants flown before and currently.
The raptors are/will be the first full-flow closed cycle engine to fly, but there have been plenty of closed cycle engines with different preburner variants flown before and currently.
iannis
Musty Nester
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Spread another rumor. I won't care about that one either.
If an order existed showing her rumor to be true, and therefore not a rumor, no one would be asking her if it happened.
He could stand in times square and murder people at this point.
If an order existed showing her rumor to be true, and therefore not a rumor, no one would be asking her if it happened.
He could stand in times square and murder people at this point.
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Big Phoenix
Pronouns: zie/zhem/zer
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NASA cucked out. Changed the name of Ultima Thule to some bullshit Indian name because some people viewed the original as a Nazi reference.
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