Your null hypothesis is the thing you’re trying to disprove. For example, if I wanted to run a study to asses the effect of adding a certain growth hormone to a cell culture, my null hypothesis would be “there is no effect”. In your case, it would be “there is no difference in how much different things are liked”. From there, you’d run your study, and do your statistical analysis, for which there are different methods based on the type of data, number of groups your comparing, sample size, etc., and I’m not a statistician so I can’t say which methods are best for what you’re planning.
When it comes to p-value, to really simplify it, you can think of your p-value as the likelihood your null hypothesis is true. That’s not exactly what it means, but it’s an easy way to remember it.
Depends on what you consider reasonable. If you’re a researcher, Thorlabs has a couple for <$30k. You could also build your own, but you probably wouldn’t be asking if you had the experience necessary to do this.
If you’re a hobbyist, building your own would be an impressive project that would teach you a lot (look up spontaneous parametric down-conversion, a common way to create entangled pairs). It would also be pricey, as you would need an appropriate laser source (probably a nanosecond pulsed laser), a non-linear crystal like BBO, and a lot of miscellaneous optical components, etc. You can get this stuff second hand online for a lot cheaper than new, but it would still cost a lot for an individual. You would also need to characterize your output to ensure you’re actually getting correlated pairs, which is outside of my expertise.
That’s not really how quantum entanglement works. When particles are entangled, their quantum mechanical states cannot be described independently. So you couldn’t write down a waveform for just one particle and have it correctly describe reality, you would need the waveform of the entire state and therefore all entangled particles.
As a consequence, certain physical observables can be highly correlated between the particles. For example, if the spin of the overall entangled state of 2 particles is 0, then the spin of 1 particle will be exactly opposite the spin of the other. But these spins are only defined upon measurement (interaction with a system that is deterministic), and at that point the entangled state is collapsed. There’s no mechanism for transporting information while maintaining an entangled state.
Ignoring this fundamental issue, it still wouldn’t be possible to maintain an entangled state between particles in a pair of twins for any practical amount of time. Maintaining coherence in qubits (entailed bits) is one of the big challenges in quantum computing. If the qubits interact with the environment it breaks their entanglement. Even just thermal vibrations will destroy the state. So typically qubits are held at near absolute 0 in a dilution refrigerator. Even still, the longest a qubit has been kept coherent is 5 seconds.
Thanks, been studying a bit about entanglement, super determinism and all that. I thought it was an interesting thought about the twins but I realized it wasn’t likely for the reasons you gave. It’s almost like distance between objects is the weird part about our universe, not it’s quantum material, thus why the entanglement seems strange at a distance. The more I study about it, the more that our 3 dimensions isn’t fundamental, but only a result of wave collapse - this is why the photon doesn’t seem to care how much we try and passively manipulate it, only how it’s finally collapsed. Like how qubits can only exist in their uncertain phase for 5 secs - it’s hard to keep it from interacting/collapsing. Perhaps antimatter annihilates with our matter because of how differently the two matter types collapse their particles from each other?  It’s all so interesting…
The nuclear pulse propulsion ship from the novel Footfall.
The technology to produce a spaceship powered by exploding nuclear bombs is fairly basic. It needs to be heavy, and it needs to have massive springs to damper the shock, and thats about it.
Space elevators on a inhabited world seem like a terrible idea though. One terrorist attack and you have a giant rope that will wrap around the world twice, through lots of heavily populated areas. I can see one going from the moon towards the earth though.
I mean like you could do 10x the damage by just redirecting an asteroid or even just gunning it with a fairly aerodynamic ship, its fantasy
But also the ideal elavator would have to be lightweight anyways so eith gravity it wouldnt work against itself, and therefore pretty easily able to burn up in the atmosphere (maximized surface area with the small size).
Also they wouldn’t have to be that long, a stable orbit isn’t super high up there - more like 100km or so.
And then again all this was about desolate planets in the first place
Space elevators need to have the majority of their mass higher than geostationary orbit to hold it up, which is 22000 miles above the earth. So I suppose it wouldn’t wrap around the planet more than once. And while true you can do more damage with an asteroid, it would be a far easier target for a terrorist group than something that far away.
I think it’s probably more than confirmation bias in this case. Twins generally have a lot of shared experiences and environment. It’s not surprising that they would more dialed in to how their sibling thinks/responds.
But quantum entanglement has nothing to do with it.
A Dyson swarm is basically just a huge number solar collectors orbiting the sun. Humanity could put some individual collectors in space if we wanted to, but we don’t have anywhere near enough resources to make a full swarm.
Near-relativistic spacecraft are conceivably possible and are not too far beyond what’s possible with current technology (though would still require significant advancements). The catch is that they would be very tiny and we would have to send a stream of them to their destination.
Retinal projectors are currently under development, and advanced ones could in principle be higher quality than current VR headsets while having a very small form-factor. Optical metamaterials such as metalenses would be very useful for this, particularly if they could be designed to work at all three RGB wavelengths simultaneously (not easy).
Sure—just like every particle in every embryo is entangled with every particle of the mother’s uterus and every other thing they’ve ever interacted with.
In order for entanglement to be useful, the particles in question need to be isolated from everything else.
Generation ships. In practice they are outside our capabilities at the moment, but it’s mostly existing engineering … if you could scale up to that, and keep it functional long enough, and keep people healthy long enough, and plan for all eventualities
One that’s on the fringe of what you’re asking is warp drives. Right now it looks like you need ridiculous amount of energy and matter that may or may not exist… But General Relativity is okay with it on principle at least
Not really. It would require negative mass which as far as we know does not exist. And it would generate so much radiation in front of the warp bubble that it would decimate anything nearby when you stopped. There are tons of other major issues with it but those are just 2 I remember off the top of my head.
Of course, if there weren’t any problems people would already be trying to build that shit.
Negative gravitational mass is still a theoretical possibility: nothing’s ever proven Einstein’s equivalence principle. It could be broken for antimatter for example, which could even conveniently explain why there’s so little of it (I remember reading that this hypothesis was investigated not long ago but we can’t produce and conserve enough antimatter to reliably test that mg=mi)
The second problem isn’t an issue if you use it in the vacuum and start and end your trip with classical propulsion.
In fact, the hardest hurdle I’d read on that subject was that with the most efficient warp metrics currently known, you’d still need something like 10^60J for a small spaceship or something ridiculous like that… Orders of magnitude more energy than the mass of the whole solar system.
Which is why I said it was kind of a fringe answer. The fact that physics don’t just flat out say “no” is already kind of amazing, which isn’t to say that it’s definitely possible.
Putting aside the issue that it requires a negative energy density, there’s still the issue that it will necessarily violate causality, which is the reason FTL travel is considered problematic in the first place. Maybe it’s ultimately okay, but it may also mean that warp drives are fundamentally impossible.
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